 | us-gaap:InvestmentIncomeInterest | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncomeAlternative |
 | us-gaap:InvestmentIncomeDividend | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncomeAlternative |
 | us-gaap:InvestmentIncomeInterestAndDividend | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncomeAlternative |
 | us-gaap:InvestmentIncomeInterest | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeAlternativeStatementTable |
 | us-gaap:InvestmentIncomeDividend | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeAlternativeStatementTable |
 | us-gaap:InvestmentIncomeInterestAndDividend | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeAlternativeStatementTable |
 | us-gaap:InvestmentIncomeInterest | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncomeRealEstateExcludingREITs |
 | us-gaap:InvestmentIncomeDividend | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncomeRealEstateExcludingREITs |
 | us-gaap:InvestmentIncomeInterestAndDividend | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncomeRealEstateExcludingREITs |
 | us-gaap:InvestmentIncomeInterest | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeRealEstateExcludingREITsStatementTable |
 | us-gaap:InvestmentIncomeDividend | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeRealEstateExcludingREITsStatementTable |
 | us-gaap:InvestmentIncomeInterestAndDividend | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeRealEstateExcludingREITsStatementTable |
 | us-gaap:InvestmentIncomeInterest | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncomeRealEstateInvestmentTrusts |
 | us-gaap:InvestmentIncomeDividend | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncomeRealEstateInvestmentTrusts |
 | us-gaap:InvestmentIncomeInterestAndDividend | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncomeRealEstateInvestmentTrusts |
 | us-gaap:InvestmentIncomeInterest | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeRealEstateInvestmentTrustsStatementTable |
 | us-gaap:InvestmentIncomeDividend | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeRealEstateInvestmentTrustsStatementTable |
 | us-gaap:InvestmentIncomeInterestAndDividend | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeRealEstateInvestmentTrustsStatementTable |
 | us-gaap:InvestmentIncomeInterest | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncome |
 | us-gaap:InvestmentIncomeDividend | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncome |
 | us-gaap:InvestmentIncomeInterestAndDividend | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncome |
 | us-gaap:InvestmentIncomeInterest | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeStatementTable |
 | us-gaap:InvestmentIncomeDividend | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeStatementTable |
 | us-gaap:InvestmentIncomeInterestAndDividend | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeStatementTable |
 | us-gaap:InvestmentIncomeInterest | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecurities |
 | us-gaap:InvestmentIncomeDividend | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecurities |
 | us-gaap:InvestmentIncomeInterestAndDividend | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecurities |
 | us-gaap:InvestmentIncomeInterest | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecuritiesScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:InvestmentIncomeDividend | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecuritiesScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:InvestmentIncomeInterestAndDividend | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecuritiesScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |