Loans and Preferred Equity Held for Investment, net - Changes in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses at beginning of period	$ 109,328	$ 517
Provision for loan losses	220,572	35,059
Charge-off	(46,692)	0
Recoveries	0	(517)
Allowance for loan losses at end of period	$ 283,208	$ 35,059

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118959141&loc=d3e21338-158488

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

+ Details

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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