CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash Flows From Operating Activities:
Net income (loss)	$ 159,974	$ 46,069	$ 75,056
Adjustments to reconcile net income to net cash used for operating activities:
Stock-based compensation	6,920	5,299	1,476
Provision for loan losses	8,049	34,726	3,684
Impairment loss on real estate, held for sale	2,293	3,520	1,317
Repair and denial reserve	10,168	4,378	(345)
Allowance for doubtful accounts on purchased future receivables	1,296	11,769	5,082
Origination of loans, held for sale, at fair value	(5,356,406)	(5,076,936)	(2,621,324)
Amortization of premiums, discounts, and debt issuance costs, net	(23,563)	33,550	14,409
Purchase of loans, held for sale, at fair value	(75,666)		(9,149)
Proceeds from disposition and principal payments of loans, held for sale, at fair value	5,475,139	5,152,861	2,628,521
Net (income) loss of unconsolidated joint ventures, net of distributions	561	(1,893)	(5,716)
Realized (gains) losses, net	(182,813)	(263,332)	(101,794)
Unrealized (gains) losses, net	(43,143)	48,105	18,790
Gain on bargain purchase			(30,728)
Net changes in operating assets and liabilities
Purchased future receivables, net	8,140	14,188	(8,807)
Derivative instruments	(63,431)	(10,014)	(6,219)
Assets of consolidated VIEs (excluding loans, net), accrued interest and due from servicers	6,182	11,859	(21,265)
Receivable from third parties	9,505	(10)	7,556
Other assets	(7,261)	16,675	(26,286)
Accounts payable and other accrued liabilities	29,615	38,079	23,345
Net cash used for operating activities	(34,441)	68,893	(52,397)
Cash Flows From Investing Activities:
Origination of loans	(3,826,182)	(669,359)	(1,307,143)
Purchase of loans	(141,663)	(242,532)	(739,002)
Origination of Paycheck Protection Program loans	(2,129,830)	(105,222)
Purchase of Paycheck Protection Program loans	(3,866)
Proceeds from disposition and principal payment of Paycheck Protection Program loans	1,401,330	30,291
Purchase of mortgage backed securities, at fair value		(14,216)	(9,593)
Purchase of real estate		(329)	(117)
Investment in unconsolidated joint ventures	(59,714)	(23,707)	(26,655)
Purchase of servicing rights			(894)
Distributions in excess of cumulative earnings from unconsolidated joint ventures	18,307	4,941	15,578
Proceeds from disposition and principal payment of loans	977,096	930,944	826,702
Proceeds from sale and principal payment of mortgage backed securities, at fair value	2,015,907	12,486	14,354
Proceeds from sale of real estate, held for sale	41,746	17,261	18,983
Net cash used for business acquisitions	(11,536)		(5,005)
Net cash used for investing activities	(1,718,405)	(59,442)	(1,212,792)
Cash Flows From Financing Activities:
Proceeds from secured borrowings	12,201,084	6,765,354	5,398,657
Payment of secured borrowings	(12,758,787)	(6,663,200)	(5,087,424)
Proceeds from the Paycheck Protection Program Liquidity Facility borrowings	2,299,167	105,222
Repayment of Paycheck Protection Program Liquidity Facility borrowings	(1,433,938)	(28,945)
Proceeds from issuance of securitized debt obligations of consolidated VIEs	1,993,111	495,220	1,395,518
Repayment of securitized debt obligations of consolidated VIEs	(673,069)	(441,212)	(477,205)
Proceeds from corporate debt	303,511		104,687
Repayment of corporate debt	(50,000)
Proceeds from senior secured note	350,000
Repayment of senior secured note	(180,294)
Repayment of guaranteed loan financing	(70,388)	(102,155)	(34,704)
Repayment of deferred financing costs	(46,938)	(12,820)	(28,207)
Proceeds from issuance of equity, net of issuance costs	165,050	13,360	91,390
Payment of contingent consideration			(1,207)
Distributions from non-controlling interests, net	(226)	(250)	20
Dividend payments	(111,924)	(56,885)	(63,326)
Tender offer of preferred shares	(11,133)
Preferred stock redemption	(98,241)
Common stock repurchased		(9,235)
Settlement of share-based awards in satisfaction of withholding tax requirements	(1,293)	(1,281)
Sale of subsidiary interest to noncontrolling interests		(122)
Net cash provided by financing activities	1,875,692	63,051	1,298,199
Net increase in cash, cash equivalents, and restricted cash	122,846	72,502	33,010
Cash, cash equivalents, and restricted cash beginning balance	200,482	127,980	94,970
Cash, cash equivalents, and restricted cash ending balance	323,328	200,482	127,980
Supplemental disclosures:
Cash paid for interest	186,095	156,262	126,188
Cash paid (received) for income taxes	13,375	(8,482)	(2,661)
Supplemental disclosure: Non-cash investing activities
Loans transferred from loans, held for sale, at fair value to loans, net		714	1,262
Loans transferred from loans, net to loans, held for sale, at fair value	1,138
Consolidation of assets in securitization trusts			463,177
Loans transferred to real estate owned	9,015	11,339
Contingent consideration in connection with acquisitions	12,400
Deconsolidation of assets in securitization trusts			177,815
Supplemental disclosure: Non-cash financing activities
Common stock issued in connection with merger transactions	239,537		189,611
Consolidation of borrowings in securitization trusts			463,177
Deconsolidation of borrowings in securitization trusts			177,815
Dividends paid in stock		17,395
Share-based component of incentive fees	1,386	$ 1,806	$ 233
Conversion of OP units into common stock	$ 13,207