Value of input used to measure alternative investment.

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- Definition

Indicates valuation technique for measuring alternative investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14210-108612

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Fair Value Measurements (Significant Unobservable Inputs) (Details)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Alternative Investment, Valuation Technique [Extensible List]		us-gaap:ValuationTechniqueDiscountedCashFlowMember
Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	$ 47,746,000	$ 25,984,000
Fair Value, Nonrecurring [Member] \| Equity Method Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		25,984,000
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		24,154,000
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value, Nonrecurring [Member] \| Equity Method Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		$ 24,154,000
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value, Nonrecurring [Member] \| Measurement Input, Discount Rate [Member] \| Equity Method Investments [Member] \| Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset, measurement input		7.3
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value, Nonrecurring [Member] \| Measurement Input, Discount Rate [Member] \| Equity Method Investments [Member] \| Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset, measurement input		7.5
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value, Nonrecurring [Member] \| Measurement Input, Cap Rate [Member] \| Equity Method Investments [Member] \| Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset, measurement input		5.8
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value, Nonrecurring [Member] \| Measurement Input, Cap Rate [Member] \| Equity Method Investments [Member] \| Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset, measurement input		8.0
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value, Nonrecurring [Member] \| Measurement Input, Discount for Lack of Marketability [Member] \| Equity Method Investments [Member] \| Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset, measurement input		15.0