Fair Value - Summary of the Fair Value Write-downs to Assets Carried at nonrecurring Fair Values (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Loans:
Loans	$ 10,404	$ 110,314	$ 80,285	$ 220,572
Real Estate:
Real estate, net	3,451	272,722	33,512	282,846
Fair value, measurements, nonrecurring
Loans:
Loans	0	110,313	33,927	220,571
Real Estate:
Real estate, net	0	216,437	0	226,561
Real estate held for sale	4,565	56,285	30,500	56,285
Total	4,565	272,722	30,500	282,846
Investments in Unconsolidated Ventures:
Investments in unconsolidated ventures	0	17,600	0	17,600
Fair value, measurements, nonrecurring \| Loans and preferred equity held for investment, net
Loans:
Loans	0	99,729	2,346	209,987
Fair value, measurements, nonrecurring \| Loans held for sale
Loans:
Loans	$ 0	$ 10,584	$ 31,581	$ 10,584

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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