 | us-gaap:CashAndCashEquivalentsAtCarryingValueAbstract | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified-RealEstateOperations |
 | us-gaap:RestrictedCashAndInvestmentsCurrentAbstract | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified-RealEstateOperations |
 | us-gaap:ShortTermInvestmentsAbstract | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified-RealEstateOperations |
 | us-gaap:CashCashEquivalentsAndShortTermInvestments | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified-RealEstateOperations |
 | us-gaap:CashAndCashEquivalentsAtCarryingValueAbstract | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified-RealEstateOperationsStatementTable |
 | us-gaap:RestrictedCashAndInvestmentsCurrentAbstract | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified-RealEstateOperationsStatementTable |
 | us-gaap:ShortTermInvestmentsAbstract | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified-RealEstateOperationsStatementTable |
 | us-gaap:CashCashEquivalentsAndShortTermInvestments | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified-RealEstateOperationsStatementTable |
 | us-gaap:CashAndCashEquivalentsAtCarryingValueAbstract | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified |
 | us-gaap:RestrictedCashAndInvestmentsCurrentAbstract | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified |
 | us-gaap:ShortTermInvestmentsAbstract | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified |
 | us-gaap:CashCashEquivalentsAndShortTermInvestments | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified |
 | us-gaap:CashAndCashEquivalentsAtCarryingValueAbstract | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassifiedStatementTable |
 | us-gaap:RestrictedCashAndInvestmentsCurrentAbstract | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassifiedStatementTable |
 | us-gaap:ShortTermInvestmentsAbstract | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassifiedStatementTable |
 | us-gaap:CashCashEquivalentsAndShortTermInvestments | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassifiedStatementTable |