| IRS990/AccountantCompileOrReviewInd | 0 | 0 |
| IRS990/AccountsPayableAccrExpnssGrp/BOYAmt | 0 | 313996 |
| IRS990/AccountsPayableAccrExpnssGrp/EOYAmt | 0 | 274768 |
| IRS990/AccountsReceivableGrp/BOYAmt | 0 | 3107342 |
| IRS990/AccountsReceivableGrp/EOYAmt | 0 | 3517491 |
| IRS990/ActivitiesConductedPrtshpInd | 0 | 0 |
| IRS990/ActivityOrMissionDesc | 0 | OPERATION OF A CALIFORNIA PUBLIC CHARTER SCHOOL SERVING STUDENTS FROM GRADE 7 TO GRADE 12. |
| IRS990/AllOtherContributionsAmt | 0 | 33219 |
| IRS990/AnnualDisclosureCoveredPrsnInd | 0 | 1 |
| IRS990/AuditCommitteeInd | 0 | 1 |
| IRS990/BackupWthldComplianceInd | 0 | 1 |
| IRS990/BooksInCareOfDetail/BusinessName/BusinessNameLine1Txt | 0 | ALICIA ANDERSON CFO |
| IRS990/BooksInCareOfDetail/PhoneNum | 0 | 7602454262 |
| IRS990/BooksInCareOfDetail/USAddress/AddressLine1Txt | 0 | 15505 CIVIC DRIVE |
| IRS990/BooksInCareOfDetail/USAddress/CityNm | 0 | VICTORVILLE |
| IRS990/BooksInCareOfDetail/USAddress/StateAbbreviationCd | 0 | CA |
| IRS990/BooksInCareOfDetail/USAddress/ZIPCd | 0 | 92392 |
| IRS990/BusinessRlnWithFamMemInd | 0 | 0 |
| IRS990/BusinessRlnWithOfficerEntInd | 0 | 0 |
| IRS990/BusinessRlnWithOrgMemInd | 0 | 0 |
| IRS990/ChangeToOrgDocumentsInd | 0 | 0 |
| IRS990/CntrctRcvdGreaterThan100KCnt | 0 | 2 |
| IRS990/CollectionsOfArtInd | 0 | 0 |
| IRS990/CompCurrentOfcrDirectorsGrp/ManagementAndGeneralAmt | 0 | 17200 |
| IRS990/CompCurrentOfcrDirectorsGrp/ProgramServicesAmt | 0 | 287551 |
| IRS990/CompCurrentOfcrDirectorsGrp/TotalAmt | 0 | 304751 |
| IRS990/CompensationFromOtherSrcsInd | 0 | 0 |
| IRS990/CompensationProcessCEOInd | 0 | 1 |
| IRS990/CompensationProcessOtherInd | 0 | 1 |
| IRS990/ConflictOfInterestPolicyInd | 0 | 1 |
| IRS990/ConservationEasementsInd | 0 | 0 |
| IRS990/ConsolidatedAuditFinclStmtInd | 0 | 0 |
| IRS990/ContractorCompensationGrp/CompensationAmt | 0 | 115845 |
| IRS990/ContractorCompensationGrp/CompensationAmt | 1 | 110590 |
| IRS990/ContractorCompensationGrp/ContractorAddress/USAddress/AddressLine1Txt | 0 | 13002 MARQUETTE COURT |
| IRS990/ContractorCompensationGrp/ContractorAddress/USAddress/AddressLine1Txt | 1 | PO BOX 476 |
| IRS990/ContractorCompensationGrp/ContractorAddress/USAddress/CityNm | 0 | VICTORVILLE |
| IRS990/ContractorCompensationGrp/ContractorAddress/USAddress/CityNm | 1 | MONTCLAIR |
| IRS990/ContractorCompensationGrp/ContractorAddress/USAddress/StateAbbreviationCd | 0 | CA |
| IRS990/ContractorCompensationGrp/ContractorAddress/USAddress/StateAbbreviationCd | 1 | CA |
| IRS990/ContractorCompensationGrp/ContractorAddress/USAddress/ZIPCd | 0 | 92392 |
| IRS990/ContractorCompensationGrp/ContractorAddress/USAddress/ZIPCd | 1 | 91763 |
| IRS990/ContractorCompensationGrp/ContractorName/BusinessName/BusinessNameLine1Txt | 0 | DURHAM CLEANING SERVICES |
| IRS990/ContractorCompensationGrp/ContractorName/BusinessName/BusinessNameLine1Txt | 1 | NO LIMIT ELECTRIC |
| IRS990/ContractorCompensationGrp/ServicesDesc | 0 | CLEANING SERVICES |
| IRS990/ContractorCompensationGrp/ServicesDesc | 1 | REPAIR & MAINTENANCE |
| IRS990/CreditCounselingInd | 0 | 0 |
| IRS990/CYBenefitsPaidToMembersAmt | 0 | 0 |
| IRS990/CYContributionsGrantsAmt | 0 | 20601198 |
| IRS990/CYGrantsAndSimilarPaidAmt | 0 | 13250 |
| IRS990/CYInvestmentIncomeAmt | 0 | 19531 |
| IRS990/CYOtherExpensesAmt | 0 | 8927795 |
| IRS990/CYOtherRevenueAmt | 0 | 145657 |
| IRS990/CYProgramServiceRevenueAmt | 0 | 78558 |
| IRS990/CYRevenuesLessExpensesAmt | 0 | -538561 |
| IRS990/CYSalariesCompEmpBnftPaidAmt | 0 | 12442460 |
| IRS990/CYTotalExpensesAmt | 0 | 21383505 |
| IRS990/CYTotalFundraisingExpenseAmt | 0 | 0 |
| IRS990/CYTotalProfFndrsngExpnsAmt | 0 | 0 |
| IRS990/CYTotalRevenueAmt | 0 | 20844944 |
| IRS990/DecisionsSubjectToApprovaInd | 0 | 0 |
| IRS990/DeductibleArtContributionInd | 0 | 0 |
| IRS990/DeductibleNonCashContriInd | 0 | 0 |
| IRS990/DelegationOfMgmtDutiesInd | 0 | 1 |
| IRS990/DepreciationDepletionGrp/ManagementAndGeneralAmt | 0 | 1246520 |
| IRS990/DepreciationDepletionGrp/TotalAmt | 0 | 1246520 |
| IRS990/Desc | 0 | EXCELSIOR OPERATES A VARIETY OF EDUCATIONAL PROGRAMS, PREDOMINATELY A NON-CLASSROOM-BASED MODEL. STUDENTS, IN GRADES 7-12, ARE WELCOME FROM THE SURROUNDING COMMUNITY AS WELL AS WITHIN THE BOUNDARIES SET BY THE STATE. EXCELSIOR SEEKS TO SERVE THOSE STUDENTS WHO WILL BE BEST EDUCATED IN AN ALTERNATIVE SETTING, OUTSIDE THE TRADITIONAL CLASSROOM ENVIRONMENT, BY PROVIDING THE SUPPORT AND RESOURCES UNIQUELY DESIGNED FOR THE GRADUATE TO ACHIEVE HIS/HER LIFE GOALS. THE COOPERATIVE TEAM OF STAFF, STUDENTS AND FAMILY DIRECTS THE EDUCATIONAL PROCESS. |
| IRS990/DescribedInSection501c3Ind | 0 | 1 |
| IRS990/DisregardedEntityInd | 0 | 0 |
| IRS990/DocumentRetentionPolicyInd | 0 | 1 |
| IRS990/DonorAdvisedFundInd | 0 | 0 |
| IRS990/ElectionOfBoardMembersInd | 0 | 0 |
| IRS990/EmployeeCnt | 0 | 216 |
| IRS990/EmploymentTaxReturnsFiledInd | 0 | 1 |
| IRS990/EngagedInExcessBenefitTransInd | 0 | 0 |
| IRS990/ExpenseAmt | 0 | 16171760 |
| IRS990/FamilyOrBusinessRlnInd | 0 | 0 |
| IRS990/FederalGrantAuditRequiredInd | 0 | 0 |
| IRS990/FeesForServicesLegalGrp/ManagementAndGeneralAmt | 0 | 88185 |
| IRS990/FeesForServicesLegalGrp/TotalAmt | 0 | 88185 |
| IRS990/FeesForServicesOtherGrp/ManagementAndGeneralAmt | 0 | 912037 |
| IRS990/FeesForServicesOtherGrp/ProgramServicesAmt | 0 | 569830 |
| IRS990/FeesForServicesOtherGrp/TotalAmt | 0 | 1481867 |
| IRS990/ForeignActivitiesInd | 0 | 0 |
| IRS990/ForeignFinancialAccountInd | 0 | 0 |
| IRS990/ForeignOfficeInd | 0 | 0 |
| IRS990/Form8282PropertyDisposedOfInd | 0 | 0 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRltdOrgRt | 0 | 10.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 0 | 6.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 1 | 6.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 2 | 6.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 3 | 6.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 4 | 6.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 5 | 6.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 6 | 40.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 7 | 40.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 8 | 40.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 9 | 40.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 10 | 40.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 11 | 40.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 12 | 40.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 13 | 40.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 14 | 40.00 |
| IRS990/Form990PartVIISectionAGrp/AverageHoursPerWeekRt | 15 | 40.00 |
| IRS990/Form990PartVIISectionAGrp/HighestCompensatedEmployeeInd | 0 | X |
| IRS990/Form990PartVIISectionAGrp/HighestCompensatedEmployeeInd | 1 | X |
| IRS990/Form990PartVIISectionAGrp/HighestCompensatedEmployeeInd | 2 | X |
| IRS990/Form990PartVIISectionAGrp/HighestCompensatedEmployeeInd | 3 | X |
| IRS990/Form990PartVIISectionAGrp/HighestCompensatedEmployeeInd | 4 | X |
| IRS990/Form990PartVIISectionAGrp/IndividualTrusteeOrDirectorInd | 0 | X |
| IRS990/Form990PartVIISectionAGrp/IndividualTrusteeOrDirectorInd | 1 | X |
| IRS990/Form990PartVIISectionAGrp/IndividualTrusteeOrDirectorInd | 2 | X |
| IRS990/Form990PartVIISectionAGrp/IndividualTrusteeOrDirectorInd | 3 | X |
| IRS990/Form990PartVIISectionAGrp/IndividualTrusteeOrDirectorInd | 4 | X |
| IRS990/Form990PartVIISectionAGrp/IndividualTrusteeOrDirectorInd | 5 | X |
| IRS990/Form990PartVIISectionAGrp/KeyEmployeeInd | 0 | X |
| IRS990/Form990PartVIISectionAGrp/KeyEmployeeInd | 1 | X |
| IRS990/Form990PartVIISectionAGrp/KeyEmployeeInd | 2 | X |
| IRS990/Form990PartVIISectionAGrp/OfficerInd | 0 | X |
| IRS990/Form990PartVIISectionAGrp/OfficerInd | 1 | X |
| IRS990/Form990PartVIISectionAGrp/OfficerInd | 2 | X |
| IRS990/Form990PartVIISectionAGrp/OfficerInd | 3 | X |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 0 | 0 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 1 | 0 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 2 | 0 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 3 | 0 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 4 | 0 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 5 | 0 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 6 | 25038 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 7 | 0 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 8 | 14862 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 9 | 9098 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 10 | 15389 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 11 | 13209 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 12 | 7976 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 13 | 12154 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 14 | 11481 |
| IRS990/Form990PartVIISectionAGrp/OtherCompensationAmt | 15 | 12072 |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 0 | GUY BURNETT |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 1 | WAYNE COSTA |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 2 | LUCY RIVERA |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 3 | ALAN KAY |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 4 | TERRANCE STONE |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 5 | SUSAN KEIGHTLEY |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 6 | PETER WRIGHT |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 7 | ALICIA ANDERSON |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 8 | RONNIE D HENDERSON |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 9 | DEREK KING |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 10 | JAMIE LOWE |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 11 | CAMREN E JONES |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 12 | LETICIA PEREZ |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 13 | MARIE SILVA |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 14 | ALARIC SINGLETARY |
| IRS990/Form990PartVIISectionAGrp/PersonNm | 15 | BRIAN LAMERS |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 0 | 4800 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 1 | 4800 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 2 | 4800 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 3 | 1600 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 4 | 1200 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 5 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 6 | 262513 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 7 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 8 | 153134 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 9 | 150172 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 10 | 161082 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 11 | 126875 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 12 | 126945 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 13 | 118859 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 14 | 112172 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromOrgAmt | 15 | 117804 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 0 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 1 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 2 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 3 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 4 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 5 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 6 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 7 | 199768 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 8 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 9 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 10 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 11 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 12 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 13 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 14 | 0 |
| IRS990/Form990PartVIISectionAGrp/ReportableCompFromRltdOrgAmt | 15 | 0 |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 0 | PRESIDENT |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 1 | VICE PRESIDENT |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 2 | TRUSTEE |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 3 | TRUSTEE |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 4 | TRUSTEE |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 5 | TRUSTEE |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 6 | SUPERINTENDENT |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 7 | CFO |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 8 | DEPUTY SUPT |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 9 | ASST SUPT STUDENT SERVICES |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 10 | ASST SUPT ADMIN |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 11 | PRINCIPAL |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 12 | PRINCIPAL |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 13 | SPECIAL ED DIRECTOR |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 14 | PRINCIPAL |
| IRS990/Form990PartVIISectionAGrp/TitleTxt | 15 | PRINCIPAL |
| IRS990/Form990ProvidedToGvrnBodyInd | 0 | 1 |
| IRS990/FormationYr | 0 | 2008 |
| IRS990/FormerOfcrEmployeesListedInd | 0 | 0 |
| IRS990/FSAuditedBasisGrp/SeparateBasisFinclStmtInd | 0 | X |
| IRS990/FSAuditedInd | 0 | 1 |
| IRS990/FundraisingActivitiesInd | 0 | 0 |
| IRS990/GamingActivitiesInd | 0 | 0 |
| IRS990/GoverningBodyVotingMembersCnt | 0 | 6 |
| IRS990/GovernmentGrantsAmt | 0 | 20567979 |
| IRS990/GrantAmt | 0 | 13250 |
| IRS990/GrantsToDomesticIndividualsGrp/ProgramServicesAmt | 0 | 13250 |
| IRS990/GrantsToDomesticIndividualsGrp/TotalAmt | 0 | 13250 |
| IRS990/GrantsToIndividualsInd | 0 | 1 |
| IRS990/GrantsToOrganizationsInd | 0 | 0 |
| IRS990/GrantToRelatedPersonInd | 0 | 0 |
| IRS990/GrossReceiptsAmt | 0 | 20844944 |
| IRS990/GroupReturnForAffiliatesInd | 0 | 0 |
| IRS990/IncludeFIN48FootnoteInd | 0 | 1 |
| IRS990/IndependentAuditFinclStmtInd | 0 | 1 |
| IRS990/IndependentVotingMemberCnt | 0 | 6 |
| IRS990/IndivRcvdGreaterThan100KCnt | 0 | 11 |
| IRS990/IndoorTanningServicesInd | 0 | 0 |
| IRS990/InfoInScheduleOPartVIInd | 0 | X |
| IRS990/InformationTechnologyGrp/ManagementAndGeneralAmt | 0 | 321481 |
| IRS990/InformationTechnologyGrp/ProgramServicesAmt | 0 | 193321 |
| IRS990/InformationTechnologyGrp/TotalAmt | 0 | 514802 |
| IRS990/InsuranceGrp/ManagementAndGeneralAmt | 0 | 199202 |
| IRS990/InsuranceGrp/TotalAmt | 0 | 199202 |
| IRS990/InvestmentIncomeGrp/ExclusionAmt | 0 | 19531 |
| IRS990/InvestmentIncomeGrp/TotalRevenueColumnAmt | 0 | 19531 |
| IRS990/InvestmentInJointVentureInd | 0 | 0 |
| IRS990/IRPDocumentCnt | 0 | 31 |
| IRS990/IRPDocumentW2GCnt | 0 | 0 |
| IRS990/LandBldgEquipAccumDeprecAmt | 0 | 7408982 |
| IRS990/LandBldgEquipBasisNetGrp/BOYAmt | 0 | 33048127 |
| IRS990/LandBldgEquipBasisNetGrp/EOYAmt | 0 | 32117254 |
| IRS990/LandBldgEquipCostOrOtherBssAmt | 0 | 39526236 |
| IRS990/LegalDomicileStateCd | 0 | CA |
| IRS990/LoanOutstandingInd | 0 | 0 |
| IRS990/LobbyingActivitiesInd | 0 | 0 |
| IRS990/LocalChaptersInd | 0 | 0 |
| IRS990/MaterialDiversionOrMisuseInd | 0 | 0 |
| IRS990/MembersOrStockholdersInd | 0 | 0 |
| IRS990/MethodOfAccountingAccrualInd | 0 | X |
| IRS990/MinutesOfCommitteesInd | 0 | 1 |
| IRS990/MinutesOfGoverningBodyInd | 0 | 1 |
| IRS990/MissionDesc | 0 | EEC'S MISSION IS "PREPARING STUDENTS TO BE SUCCESSFUL ADULTS." |
| IRS990/MoreThan5000KToIndividualsInd | 0 | 0 |
| IRS990/MoreThan5000KToOrgInd | 0 | 0 |
| IRS990/NetAssetsOrFundBalancesBOYAmt | 0 | 40522188 |
| IRS990/NetAssetsOrFundBalancesEOYAmt | 0 | 39983627 |
| IRS990/NetUnrelatedBusTxblIncmAmt | 0 | 0 |
| IRS990/NondeductibleContributionsInd | 0 | 0 |
| IRS990/OccupancyGrp/ManagementAndGeneralAmt | 0 | 1177191 |
| IRS990/OccupancyGrp/ProgramServicesAmt | 0 | 468 |
| IRS990/OccupancyGrp/TotalAmt | 0 | 1177659 |
| IRS990/OfficeExpensesGrp/ManagementAndGeneralAmt | 0 | 581839 |
| IRS990/OfficeExpensesGrp/ProgramServicesAmt | 0 | 396816 |
| IRS990/OfficeExpensesGrp/TotalAmt | 0 | 978655 |
| IRS990/OfficerMailingAddressInd | 0 | 0 |
| IRS990/OperateHospitalInd | 0 | 0 |
| IRS990/Organization501c3Ind | 0 | X |
| IRS990/OrganizationFollowsSFAS117Ind | 0 | X |
| IRS990/OtherChangesInNetAssetsAmt | 0 | 0 |
| IRS990/OtherEmployeeBenefitsGrp/ManagementAndGeneralAmt | 0 | 35173 |
| IRS990/OtherEmployeeBenefitsGrp/ProgramServicesAmt | 0 | 1971783 |
| IRS990/OtherEmployeeBenefitsGrp/TotalAmt | 0 | 2006956 |
| IRS990/OtherExpensesGrp/Desc | 0 | BOOKS AND SUPPLIES |
| IRS990/OtherExpensesGrp/Desc | 1 | DUES AND MEMBERSHIPS |
| IRS990/OtherExpensesGrp/Desc | 2 | MAINTENANCE AND REPAIRS |
| IRS990/OtherExpensesGrp/ManagementAndGeneralAmt | 0 | 67213 |
| IRS990/OtherExpensesGrp/ManagementAndGeneralAmt | 1 | 29312 |
| IRS990/OtherExpensesGrp/ProgramServicesAmt | 0 | 277864 |
| IRS990/OtherExpensesGrp/ProgramServicesAmt | 1 | 7599 |
| IRS990/OtherExpensesGrp/TotalAmt | 0 | 277864 |
| IRS990/OtherExpensesGrp/TotalAmt | 1 | 74812 |
| IRS990/OtherExpensesGrp/TotalAmt | 2 | 29312 |
| IRS990/OtherRevenueMiscGrp/BusinessCd | 0 | 611710 |
| IRS990/OtherRevenueMiscGrp/BusinessCd | 1 | 524298 |
| IRS990/OtherRevenueMiscGrp/Desc | 0 | E-RATE |
| IRS990/OtherRevenueMiscGrp/Desc | 1 | IPAD INSURANCE/TRADE |
| IRS990/OtherRevenueMiscGrp/ExclusionAmt | 0 | 131178 |
| IRS990/OtherRevenueMiscGrp/ExclusionAmt | 1 | 14479 |
| IRS990/OtherRevenueMiscGrp/TotalRevenueColumnAmt | 0 | 131178 |
| IRS990/OtherRevenueMiscGrp/TotalRevenueColumnAmt | 1 | 14479 |
| IRS990/OtherRevenueTotalAmt | 0 | 145657 |
| IRS990/OtherSalariesAndWagesGrp/ManagementAndGeneralAmt | 0 | 81304 |
| IRS990/OtherSalariesAndWagesGrp/ProgramServicesAmt | 0 | 8032563 |
| IRS990/OtherSalariesAndWagesGrp/TotalAmt | 0 | 8113867 |
| IRS990/PartialLiquidationInd | 0 | 0 |
| IRS990/PaymentsToAffiliatesGrp/ManagementAndGeneralAmt | 0 | 315600 |
| IRS990/PaymentsToAffiliatesGrp/ProgramServicesAmt | 0 | 2247636 |
| IRS990/PaymentsToAffiliatesGrp/TotalAmt | 0 | 2563236 |
| IRS990/PayPremiumsPrsnlBnftCntrctInd | 0 | 0 |
| IRS990/PayrollTaxesGrp/ManagementAndGeneralAmt | 0 | 10375 |
| IRS990/PayrollTaxesGrp/ProgramServicesAmt | 0 | 394169 |
| IRS990/PayrollTaxesGrp/TotalAmt | 0 | 404544 |
| IRS990/PensionPlanContributionsGrp/ManagementAndGeneralAmt | 0 | 11732 |
| IRS990/PensionPlanContributionsGrp/ProgramServicesAmt | 0 | 1600610 |
| IRS990/PensionPlanContributionsGrp/TotalAmt | 0 | 1612342 |
| IRS990/PoliticalCampaignActyInd | 0 | 0 |
| IRS990/PrepaidExpensesDefrdChargesGrp/BOYAmt | 0 | 614776 |
| IRS990/PrepaidExpensesDefrdChargesGrp/EOYAmt | 0 | 546450 |
| IRS990/ProfessionalFundraisingInd | 0 | 0 |
| IRS990/ProgramServiceRevenueGrp/BusinessCd | 0 | 611710 |
| IRS990/ProgramServiceRevenueGrp/Desc | 0 | STUDENT ACTIVITIES |
| IRS990/ProgramServiceRevenueGrp/RelatedOrExemptFuncIncomeAmt | 0 | 78558 |
| IRS990/ProgramServiceRevenueGrp/TotalRevenueColumnAmt | 0 | 78558 |
| IRS990/ProhibitedTaxShelterTransInd | 0 | 0 |
| IRS990/PYBenefitsPaidToMembersAmt | 0 | 0 |
| IRS990/PYContributionsGrantsAmt | 0 | 20355085 |
| IRS990/PYExcessBenefitTransInd | 0 | 0 |
| IRS990/PYGrantsAndSimilarPaidAmt | 0 | 0 |
| IRS990/PYInvestmentIncomeAmt | 0 | 18462 |
| IRS990/PYOtherExpensesAmt | 0 | 9917184 |
| IRS990/PYOtherRevenueAmt | 0 | 82834 |
| IRS990/PYProgramServiceRevenueAmt | 0 | 47660 |
| IRS990/PYRevenuesLessExpensesAmt | 0 | -1767642 |
| IRS990/PYSalariesCompEmpBnftPaidAmt | 0 | 12354499 |
| IRS990/PYTotalExpensesAmt | 0 | 22271683 |
| IRS990/PYTotalProfFndrsngExpnsAmt | 0 | 0 |
| IRS990/PYTotalRevenueAmt | 0 | 20504041 |
| IRS990/QuidProQuoContributionsInd | 0 | 0 |
| IRS990/RcvFndsToPayPrsnlBnftCntrctInd | 0 | 0 |
| IRS990/ReconcilationRevenueExpnssAmt | 0 | -538561 |
| IRS990/RegularMonitoringEnfrcInd | 0 | 1 |
| IRS990/RelatedEntityInd | 0 | 1 |
| IRS990/RelatedOrganizationCtrlEntInd | 0 | 0 |
| IRS990/ReportInvestmentsOtherSecInd | 0 | 0 |
| IRS990/ReportLandBuildingEquipmentInd | 0 | 1 |
| IRS990/ReportOtherAssetsInd | 0 | 0 |
| IRS990/ReportOtherLiabilitiesInd | 0 | 0 |
| IRS990/ReportProgramRelatedInvstInd | 0 | 0 |
| IRS990/RevenueAmt | 0 | 20567979 |
| IRS990/SavingsAndTempCashInvstGrp/BOYAmt | 0 | 4065939 |
| IRS990/SavingsAndTempCashInvstGrp/EOYAmt | 0 | 4077200 |
| IRS990ScheduleA/SchoolInd | 0 | X |
| IRS990/ScheduleBRequiredInd | 0 | 1 |
| IRS990ScheduleD/BuildingsGrp/BookValueAmt | 0 | 30172462 |
| IRS990ScheduleD/BuildingsGrp/DepreciationAmt | 0 | 5769611 |
| IRS990ScheduleD/BuildingsGrp/OtherCostOrOtherBasisAmt | 0 | 35942073 |
| IRS990ScheduleD/EquipmentGrp/BookValueAmt | 0 | 727260 |
| IRS990ScheduleD/EquipmentGrp/DepreciationAmt | 0 | 1475384 |
| IRS990ScheduleD/EquipmentGrp/OtherCostOrOtherBasisAmt | 0 | 2202644 |
| IRS990ScheduleD/ExpensesNotReportedAmt | 0 | 0 |
| IRS990ScheduleD/ExpensesNotRptFinclStmtAmt | 0 | 0 |
| IRS990ScheduleD/ExpensesSubtotalAmt | 0 | 21383505 |
| IRS990ScheduleD/FootnoteTextInd | 0 | X |
| IRS990ScheduleD/LandGrp/BookValueAmt | 0 | 140423 |
| IRS990ScheduleD/LandGrp/OtherCostOrOtherBasisAmt | 0 | 140423 |
| IRS990ScheduleD/LeaseholdImprovementsGrp/BookValueAmt | 0 | 1077109 |
| IRS990ScheduleD/LeaseholdImprovementsGrp/DepreciationAmt | 0 | 163987 |
| IRS990ScheduleD/LeaseholdImprovementsGrp/OtherCostOrOtherBasisAmt | 0 | 1241096 |
| IRS990ScheduleD/RevenueNotReportedAmt | 0 | 0 |
| IRS990ScheduleD/RevenueNotReportedFinclStmtAmt | 0 | 0 |
| IRS990ScheduleD/RevenueSubtotalAmt | 0 | 20844944 |
| IRS990ScheduleD/SupplementalInformationDetail/ExplanationTxt | 0 | MANAGEMENT BELIEVES ALL OF ITS SIGNIFICANT TAX POSITIONS WOULD BE UPHELD UNDER EXAMINATION; THEREFORE, NO PROVISION FOR INCOME TAX HAS BEEN RECORDED. |
| IRS990ScheduleD/SupplementalInformationDetail/FormAndLineReferenceDesc | 0 | PART X, LINE 2: |
| IRS990ScheduleD/TotalBookValueLandBuildingsAmt | 0 | 32117254 |
| IRS990ScheduleD/TotalExpensesPerForm990Amt | 0 | 21383505 |
| IRS990ScheduleD/TotalRevenuePerForm990Amt | 0 | 20844944 |
| IRS990ScheduleD/TotalRevEtcAuditedFinclStmtAmt | 0 | 20844944 |
| IRS990ScheduleD/TotExpnsEtcAuditedFinclStmtAmt | 0 | 21383505 |
| IRS990ScheduleE/ComplianceWithRevProc7550Ind | 0 | 1 |
| IRS990ScheduleE/DiscriminateRaceAdmissPlcyInd | 0 | 0 |
| IRS990ScheduleE/DiscriminateRaceAthltProgInd | 0 | 0 |
| IRS990ScheduleE/DiscriminateRaceEducPlcyInd | 0 | 0 |
| IRS990ScheduleE/DiscriminateRaceEmplmFcultyInd | 0 | 0 |
| IRS990ScheduleE/DiscriminateRaceOtherActyInd | 0 | 0 |
| IRS990ScheduleE/DiscriminateRaceSchsInd | 0 | 0 |
| IRS990ScheduleE/DiscriminateRaceStdntsRghtsInd | 0 | 0 |
| IRS990ScheduleE/DiscriminateRaceUseOfFcltsInd | 0 | 0 |
| IRS990ScheduleE/GovernmentFinancialAidRcvdInd | 0 | 1 |
| IRS990ScheduleE/GovernmentFinancialAidRvkdInd | 0 | 0 |
| IRS990ScheduleE/MaintainCpyOfAllSolInd | 0 | 1 |
| IRS990ScheduleE/MaintainCpyOfBrochuresEtcInd | 0 | 1 |
| IRS990ScheduleE/MaintainRacialCompRecsInd | 0 | 1 |
| IRS990ScheduleE/MaintainScholarshipsRecsInd | 0 | 0 |
| IRS990ScheduleE/NondiscriminatoryPolicyStmtInd | 0 | 1 |
| IRS990ScheduleE/PlcyPblczdViaBroadcastMediaInd | 0 | 1 |
| IRS990ScheduleE/PolicyStmtInBrochuresEtcInd | 0 | 1 |
| IRS990ScheduleE/SupplementalInformationDetail/ExplanationTxt | 0 | AS A PUBLIC CHARTER SCHOOL, THE ORGANIZATION INCLUDES A NONDISCRIMINATORY POLICY WITHIN ITS APPROVED CHARTER PETITION. THE CHARTER PETITION IS A PUBLIC DOCUMENT AVAILABLE ON THE ORGANIZATION'S WEBSITE. |
| IRS990ScheduleE/SupplementalInformationDetail/ExplanationTxt | 1 | THE ORGANIZATION IS A PUBLIC CHARTER SCHOOL THAT OPERATES TUITION-FREE; THEREFORE, SCHOLARSHIPS AND FINANCIAL ASSISTANCE ARE NOT APPLICABLE. |
| IRS990ScheduleE/SupplementalInformationDetail/ExplanationTxt | 2 | THE ORGANIZATION RECEIVES FINANCIAL ASSISTANCE FROM THE U.S. AND CALIFORNIA DEPARTMENTS OF EDUCATION AND THE COUNTY OF SAN BERNARDINO, CALIFORNIA AS PART OF ITS OPERATION AS A PUBLIC CHARTER SCHOOL. |
| IRS990ScheduleE/SupplementalInformationDetail/FormAndLineReferenceDesc | 0 | SCHEDULE E, PART I, LINE 3 |
| IRS990ScheduleE/SupplementalInformationDetail/FormAndLineReferenceDesc | 1 | SCHEDULE E, PART I, LINE 4 |
| IRS990ScheduleE/SupplementalInformationDetail/FormAndLineReferenceDesc | 2 | SCHEDULE E, PART I, LINE 6 |
| IRS990ScheduleI/GrantRecordsMaintainedInd | 0 | 1 |
| IRS990ScheduleI/GrantsOtherAsstToIndivInUSGrp/CashGrantAmt | 0 | 13250 |
| IRS990ScheduleI/GrantsOtherAsstToIndivInUSGrp/GrantTypeTxt | 0 | STUDENT SCHOLARSHIPS |
| IRS990ScheduleI/GrantsOtherAsstToIndivInUSGrp/RecipientCnt | 0 | 9 |
| IRS990ScheduleI/GrantsOtherAsstToIndivInUSGrp/ValuationMethodUsedDesc | 0 | CASH |
| IRS990ScheduleI/SupplementalInformationDetail/ExplanationTxt | 0 | STUDENTS MUST SUBMIT AN APPLICATION AND ESSAY, ALONG WITH A TEACHER RECOMMENDATION LETTER, TO BE CONSIDERED FOR A SCHOLARSHIP. A COMMITTE SELECTS THE AWARD WINNERS BASED ON MERIT. THE FUNDS FOR THE STUDENTS ARE HELD IN TRUST IN THE FOUNDATION ACCOUNT UNTIL THE STUDENT GRADUATES FROM EXCELSIOR. |
| IRS990ScheduleI/SupplementalInformationDetail/FormAndLineReferenceDesc | 0 | PART I, LINE 2: |
| IRS990ScheduleJ/AnyNonFixedPaymentsInd | 0 | 0 |
| IRS990ScheduleJ/BoardOrCommitteeApprovalInd | 0 | X |
| IRS990ScheduleJ/CompBasedOnRevenueOfFlngOrgInd | 0 | 0 |
| IRS990ScheduleJ/CompBsdNetEarnsFlngOrgInd | 0 | 0 |