Real Estate Assets, Net - Schedule of ROE Held-For-Sale (Details) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2021 USD ($) property		Sep. 30, 2020 USD ($) property	Sep. 30, 2021 USD ($) property		Sep. 30, 2020 USD ($) property
Count
Balance at beginning of period | property	25		42	38		68
Net transfers from mortgage loans | property	10		5	17		12
Adjustments to record at lower of cost or fair value  | property	0		0	0		0
Depreciation on rental properties | property	0		0	0		0
Disposals | property	(4)		(7)	(24)		(40)
Other | property	0		0	0		0
Balance at end of period | property	31		40	31		40
Amount
Balance at beginning of period | $	$ 4,768		$ 8,233	$ 8,526	[1]	$ 15,071
Net transfers from mortgage loans | $	1,739		603	3,013		1,515
Adjustments to record at lower of cost or fair value  | $	78		(156)	(170)		(1,156)
Depreciation on rental properties | $	(1)		(7)	(7)		(23)
Disposals | $	(487)		(1,416)	(5,265)		(8,143)
Other | $	0		(49)	0		(56)
Balance at end of period | $	$ 6,097	[1]	$ 7,208	$ 6,097	[1]	$ 7,208

[1] Real estate owned properties, net, are presented net of valuation allowances of $0.4 million and $1.4 million at September 30, 2021 and December 31, 2020, respectively.