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	$ 170,389	$ 205,668	$ 174,046
Adjustments to reconcile net income to net cash provided by operating activities:
Accretion of origination fees on loans receivable, net	(25,237)	(27,859)	(23,055)
Accretion of origination fees on interests in loans receivable, net	(1,250)	(451)	(535)
Amortization of financing costs	21,307	19,638	13,400
Non-cash equity compensation	8,812	5,670	25,495
Other income	(5,855)
Depreciation on real estate owned	7,113
Gain on foreclosure of real estate owned	(1,430)
Non-cash advances to loans receivable in lieu of interest	(69,291)	(90,065)	(56,709)
Non-cash advances to interests in loans receivable in lieu of interest	(18,733)	(13,782)	(6,379)
Non-cash advances on secured financings in lieu of interest	18,134	19,869	2,255
Repayment of non-cash advances to loans receivable in lieu of interest	126,865	15,784	6,226
Repayment of non-cash advances to interests in loans receivable in lieu of interest	27,903	1,566
Repayment of non-cash advances to secured financings in lieu of interest	(40,556)	(1,238)
Realized (gain) loss on sale of investments	141	640	(103)
Provision for (reversal of) current expected credit loss reserve	(8,962)	6,000
Equity in income from investment in CMTG/CN Mortgage REIT LLC			(40)
Distributions of income from CMTG/CN Mortgage REIT LLC			40
Changes in operating assets and liabilities:
Accrued interest receivable	9,460	165	(13,190)
Other assets	(10,062)	756	(519)
Accounts payable, accrued expenses and other liabilities	6,800	(915)	413
Interest payable	(1,938)	1,146	5,452
Due to/from affiliate		(25)	(11)
Management fee payable - affiliate	134	978	1,375
Incentive fee payable - affiliate	(187)	(3,050)	1,392
Net cash provided by operating activities	213,557	140,495	129,553
Cash flows from investing activities
Loan originations, acquisitions and advances, net of fees	(2,924,699)	(791,667)	(3,256,212)
Advances of interests in loans receivable, net of fees	(101,767)	(118,582)	(64,031)
Repayments of loans receivable	2,312,184	535,565	660,813
Repayments of interests in loans receivable	269,988	15,417
Extension and exit fees received from loans receivable	9,269	2,048	3,404
Extension and exit fees received from interests in loans receivable	265	453
Cash, cash equivalents and restricted cash acquired from foreclosure of properties	9,580
Acquisition of real estate owned	(11,463)
Sale of loans receivable	48,006	151,017	342,377
Return of capital distribution from CMTG/CN Mortgage REIT LLC			128
Reserves and deposits held for loans receivable	15,441	(3,112)	2,799
Net cash used in investing activities	(373,196)	(208,861)	(2,310,722)
Cash flows from financing activities
Proceeds from issuance of common stock	103,040	70,000	539,095
Treasury stock, repurchase	(3,602)
Redemption of preferred stock	(125)	(125)
Contributions from non-controlling interests	2,514	1,029
Offering costs	(13,068)	(949)	(4,840)
Dividends paid on common stock and vested restricted stock units	(196,712)	(207,569)	(172,776)
Dividends paid on redeemable common stock	(8,214)	(12,431)	(12,624)
Dividends paid on preferred stock	(16)	(31)	(31)
Distributions to non-controlling interests		(15,537)	(5,415)
Proceeds from secured financings	1,997,562	817,159	2,295,685
Proceeds from secured term loan		325,000	450,000
Payment of financing costs	(22,652)	(30,124)	(25,670)
Payment of exit fees on secured financings	(864)	(138)
Repayments of secured financings	(1,779,225)	(779,641)	(615,051)
Repayments of secured term loan	(5,837)	(5,321)	(1,125)
Repayments of debt related to real estate owned	(10,000)
Net cash provided by financing activities	62,801	161,322	2,447,248
Net (decrease) increase in cash, cash equivalents and restricted cash	(96,838)	92,956	266,079
Cash, cash equivalents and restricted cash, beginning of period	430,974	338,018	71,939
Cash, cash equivalents and restricted cash, end of period	334,136	430,974	338,018
Cash and cash equivalents, beginning of period	427,512	334,999	69,430
Restricted cash, beginning of period	3,462	3,019	2,509
Cash and cash equivalents, end of period	310,194	427,512	334,999
Restricted cash, end of period	23,942	3,462	3,019
Supplemental disclosure of cash flow information:
Cash paid for interest	158,729	131,579	118,640
Supplemental disclosure of non-cash investing and financing activities:
Dividends accrued on common stock, redeemable common stock and vested restricted stock units	51,741	50,000	55,000
Dividends accrued on unvested restricted stock units		3,480	2,354
Loan principal payments held by servicer	154,600	12,980
Accrued financing costs	6,250	394	2,884
Accrued offering costs	270	$ 1,516	$ 2,268
Working capital consolidated	(18,546)
Settlement of loan receivable	(103,901)
Real estate acquired in settlement of loan receivable	414,000
Assumption of debt related to real estate owned	(300,000)
Conversion of restricted stock units to common shares; common stock	17
Conversion of restricted stock units to common shares; additional paid in capital	(17)
Conversion of temporary equity to permanent equity; redeemable common stock	(138,081)
Conversion of temporary equity to permanent equity; stockholder's equity	$ 138,081