Condensed Consolidated Statements of Equity - USD ($) $ in Thousands	Total Starwood Property Trust, Inc. Stockholders' Equity 2023 Notes	Total Starwood Property Trust, Inc. Stockholders' Equity 2018 Notes	Total Starwood Property Trust, Inc. Stockholders' Equity	Common stock	Additional Paid-In Capital 2023 Notes	Additional Paid-In Capital 2018 Notes	Additional Paid-In Capital	Treasury Stock	Accumulated Deficit	Accumulated Other Comprehensive Income	Non-Controlling Interests	2023 Notes	2018 Notes	Total
Balance at Dec. 31, 2015			$ 4,140,316	$ 2,410			$ 4,192,844	$ (72,381)	$ (12,286)	$ 29,729	$ 30,627			$ 4,170,943
Balance (in shares) at Dec. 31, 2015				241,044,775				3,553,996
Increase (Decrease) in Stockholders' Equity
Proceeds from DRIP Plan			299				299							299
Proceeds from DRIP Plan (in shares)				14,707
Common stock repurchased			(19,723)					$ (19,723)						$ (19,723)
Common stock repurchased (in shares)								1,052,889						1,052,889
Share-based compensation			22,797	$ 12			22,785							$ 22,797
Share-based compensation (in shares)				1,147,975
Manager incentive fee paid in stock			14,657	$ 8			14,649							14,657
Manager incentive fee paid in stock (in shares)				788,460
Net income			243,896						243,896		1,034			244,930
Dividends declared, $1.44 per share			(343,913)						(343,913)					(343,913)
Other comprehensive income, net			10,519							10,519				10,519
VIE non-controlling interests											(144)			(144)
Contributions from non-controlling interests											10,417			10,417
Distribution to non-controlling interests											(5,400)			(5,400)
Balance at Sep. 30, 2016			4,068,848	$ 2,430			4,230,577	$ (92,104)	(112,303)	40,248	36,534			4,105,382
Balance (in shares) at Sep. 30, 2016				242,995,917				4,606,885
Balance at Dec. 31, 2016			4,522,274	$ 2,639			4,691,180	$ (92,104)	(115,579)	36,138	37,799			$ 4,560,073
Balance (in shares) at Dec. 31, 2016				263,893,806				4,606,885						263,893,806
Increase (Decrease) in Stockholders' Equity
Proceeds from DRIP Plan			541				541							$ 541
Proceeds from DRIP Plan (in shares)				24,217
Equity offering costs			(12)				(12)							$ (12)
Common stock repurchased (in shares)														0
Equity component of Convertible Senior Notes issuance	$ 3,755				$ 3,755							$ 3,755
Equity component of Convertible Senior Notes repurchase		$ (18,105)				$ (18,105)							$ (18,105)
Share-based compensation			13,290	$ 9			13,281							$ 13,290
Share-based compensation (in shares)				849,045
Manager incentive fee paid in stock			14,410	$ 6			14,404							14,410
Manager incentive fee paid in stock (in shares)				639,555
Net income			308,166						308,166		10,720			318,886
Dividends declared, $1.44 per share			(376,660)						(376,660)					(376,660)
Other comprehensive income, net			29,133							29,133				29,133
VIE non-controlling interests											1,837			1,837
Contributions from non-controlling interests											105			105
Distribution to non-controlling interests											(7,519)			(7,519)
Balance at Sep. 30, 2017			$ 4,496,792	$ 2,654			$ 4,705,044	$ (92,104)	$ (184,073)	$ 65,271	$ 42,942			$ 4,539,734
Balance (in shares) at Sep. 30, 2017				265,406,623				4,606,885						265,406,623