Related-Party Transactions - Acquisitions from Consolidated CMBS Trusts (Details) - Reo Portfolio - CMBS - Investing and Servicing Segment - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2019	Dec. 31, 2020
Related-Party Transactions
Assets acquired	$ 9,200,000	$ 8,600,000	$ 0
Consideration transferred	$ 10,100,000	$ 8,800,000

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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
-Publisher FASB
-Name Accounting Standards Codification
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