Consolidated Statements of Equity $ in Thousands	USD ($) shares	Cumulative Effect, Period of Adoption, Adjustment USD ($)	Total Starwood Property Trust, Inc. Stockholders’ Equity USD ($)	Total Starwood Property Trust, Inc. Stockholders’ Equity Cumulative Effect, Period of Adoption, Adjustment USD ($)	Common stock USD ($) shares	Additional Paid-in Capital USD ($)	Additional Paid-in Capital Cumulative Effect, Period of Adoption, Adjustment USD ($)	Treasury Stock​ USD ($) shares	Retained Earnings (Accumulated Deficit) USD ($)	Retained Earnings (Accumulated Deficit) Cumulative Effect, Period of Adoption, Adjustment USD ($)	Accumulated Other Comprehensive Income USD ($)	Non- Controlling Interests USD ($)
Accounting Standards Update [Extensible List]	Accounting Standards Update 2016-13 [Member]
Beginning Balance (in shares) at Dec. 31, 2018 | shares					280,839,692			5,180,140
Beginning Balance at Dec. 31, 2018	$ 4,900,189		$ 4,603,432		$ 2,808	$ 4,995,156		$ (104,194)	$ (348,998)		$ 58,660	$ 296,757
Increase (Decrease) in Stockholders' Equity
Proceeds from DRIP Plan (in shares) | shares					33,454
Proceeds from DRIP Plan	767		767			767
Redemption of Class A Units (in shares)					974,176
Redemption of Class A Units	0		21,070		$ 10	21,060						(21,070)
Equity offering costs	(27)		(27)			(27)
Conversion of 2019 Convertible Notes (in shares) | shares					3,611,918
Conversion of 2019 Convertible Notes	67,562		67,562		$ 36	67,526
Share-based compensation (in shares) | shares					1,387,346
Share-based compensation	36,155		36,155		$ 15	36,140
Manager fee paid in stock (in shares) | shares					534,305
Manager fees paid in stock	11,915		11,915		$ 5	11,910
Net income	536,935		509,664						509,664			27,271
Dividends declared	(542,385)		(542,385)						(542,385)
Other comprehensive loss, net	(7,728)		(7,728)								(7,728)
VIE non-controlling interests	(2,808)											(2,808)
Contributions from non-controlling interests	186,397											186,397
Distributions to non-controlling interests	(49,958)											(49,958)
Ending Balance (in shares) at Dec. 31, 2019 | shares					287,380,891			5,180,140
Ending Balance at Dec. 31, 2019	5,137,014	$ (32,286)	4,700,425	$ (32,286)	$ 2,874	5,132,532		$ (104,194)	(381,719)	$ (32,286)	50,932	436,589
Beginning Balance at Dec. 31, 2018	0
Ending Balance at Dec. 31, 2019	$ 0
Accounting Standards Update [Extensible List]	Accounting Standards Updated 2020-06 [Member]
Increase (Decrease) in Stockholders' Equity
Proceeds from DRIP Plan (in shares) | shares					71,776
Proceeds from DRIP Plan	$ 1,098		1,098		$ 1	1,097
Redemption of Class A Units (in shares)					409,712
Redemption of Class A Units	(1,309)		8,964		$ 4	8,960						(10,273)
Equity offering costs	$ (95)		(95)			(95)
Common stock repurchased (in shares) | shares	2,268,551							2,268,551
Common stock repurchased	$ (33,828)		(33,828)					$ (33,828)
Share-based compensation (in shares) | shares					1,807,990
Share-based compensation	31,241		31,241		$ 18	31,223
Manager fee paid in stock (in shares) | shares					2,421,232
Manager fees paid in stock	36,046		36,046		$ 24	36,022
Net income	366,081		331,689						331,689			34,392
Dividends declared	(547,417)		(547,417)						(547,417)
Other comprehensive loss, net	(6,939)		(6,939)								(6,939)
VIE non-controlling interests	(2,178)											(2,178)
Contributions from non-controlling interests	13,351											13,351
Distributions to non-controlling interests	$ (98,203)											(98,203)
Ending Balance (in shares) at Dec. 31, 2020 | shares	292,091,601				292,091,601			7,448,691
Ending Balance at Dec. 31, 2020	$ 4,862,576	$ (1,536)	4,488,898	$ (1,536)	$ 2,921	5,209,739	$ (3,755)	$ (138,022)	(629,733)	$ 2,219	43,993	373,678
Ending Balance at Dec. 31, 2020	0
Increase (Decrease) in Stockholders' Equity
Cumulative effect of investment company fair value adjustment	1,236,476		1,236,476						1,236,476
Proceeds from public offering of common stock (in shares) | shares					16,000,000
Proceeds from public offering of common stock	393,120		393,120		$ 160	392,960
Proceeds from DRIP Plan (in shares) | shares					39,957
Proceeds from DRIP Plan	966		966			966
Redemption of Class A Units (in shares)					853,681
Redemption of Class A Units	0		17,738		$ 9	17,729						(17,738)
Equity offering costs	(720)		(720)			(720)
Share-based compensation (in shares) | shares					2,568,525
Share-based compensation	39,287		39,287		$ 26	39,261
Manager fee paid in stock (in shares) | shares					715,180
Manager fees paid in stock	17,040		17,040		$ 7	17,033
Net income	492,426
Net income	491,678		447,739						447,739			43,939
Dividends declared	(563,595)		(563,595)						(563,595)
Other comprehensive loss, net	(3,040)		(3,040)								(3,040)
Contributions from non-controlling interests	5,590											5,590
Distributions to non-controlling interests	$ (43,950)		163			163						(44,113)
Ending Balance (in shares) at Dec. 31, 2021 | shares	312,268,944				312,268,944			7,448,691
Ending Balance at Dec. 31, 2021	$ 6,433,892		$ 6,072,536		$ 3,123	$ 5,673,376		$ (138,022)	$ 493,106		$ 40,953	$ 361,356
Increase (Decrease) in Temporary Equity [Roll Forward]
Net income	748
Contributions from non-controlling interests	214,167
Ending Balance at Dec. 31, 2021	$ 214,915