Fair Value Measurements - Carrying Value and Fair Value Measurements (Details) - Level 3 - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Carrying Value
Liabilities
Non-recourse secured debt, net	$ 1,207,475	$ 1,201,913
Assets
Notes receivable	28,000	28,000
Fair Value
Liabilities
Non-recourse secured debt, net	1,228,468	1,239,004
Assets
Notes receivable	$ 30,300	$ 30,300

Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant