Fair Value Measurements - Narratives (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Fair Value
Deferred financing costs	$ 6,534
Unamortized discount (premium)	(1,477)
Non recourse debt
Fair Value
Deferred financing costs	5,900	$ 6,200
Unamortized discount (premium)	3,500	3,500
Bonds payable
Fair Value
Deferred financing costs	600	700
Unamortized discount (premium)	$ (5,000)	$ (4,800)

Amount, after accumulated amortization, of debt discount (premium).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_DebtInstrumentUnamortizedDiscountPremiumNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant