Agreements and Transactions with Related Parties - Related Party Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Related Party Transaction
Distributions of Available Cash	$ 46,609	$ 47,862	$ 45,121
Interest income on deferred acquisition fees and loans to affiliates	2,055	2,103	740
Total deferred revenue earned	155,271	211,059	231,938
Asset management revenue
Related Party Transaction
Gross contract revenue	63,556	70,125	61,879
Reimbursable costs from affiliates
Related Party Transaction
Gross contract revenue	21,925	51,445	66,433
Structuring revenue
Related Party Transaction
Gross contract revenue	20,826	34,198	47,328
Dealer manager fees
Related Party Transaction
Gross contract revenue	0	4,430	8,002
Other advisory revenue
Related Party Transaction
Gross contract revenue	$ 300	$ 896	$ 2,435

Amount of interest income earned from interest-bearing assets owed to the entity by related party.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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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.

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The distributions from managed REITs during the period for services rendered. They are accounted for under the equity method.

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