Agreements and Transactions with Related Parties - Related Party Income, by Program (Details) - Affiliated Entity - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Related Party Transaction
Revenue from related parties	$ 16,607	$ 22,323
CPA:18 – Global
Related Party Transaction
Revenue from related parties	5,912	7,961
CWI 1
Related Party Transaction
Revenue from related parties	5,040	7,501
CWI 2
Related Party Transaction
Revenue from related parties	4,200	5,746
CESH
Related Party Transaction
Revenue from related parties	$ 1,455	$ 1,115

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07.1(c))
-URI http://asc.fasb.org/extlink&oid=116637345&loc=SL114874292-224272

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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Balance Type:	credit
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