Stockholders' Equity - Non-Vested Shares (Details)	3 Months Ended
	Mar. 31, 2017 $ / shares shares
Non-Vested Shares and Share Equivalents activity
Balance at the beginning of the period (in shares)	820,374
Granted (in shares)	1,470,469
Vested (in shares)	(234,386)
Forfeited (in shares)	(12,340)
Balance at the end of the period (in shares)	2,044,117
Weighted Average Grant Date Fair Value (per share)
Balance at the beginning of period (in dollars per share) | $ / shares	$ 22.34
Granted (in dollars per share) | $ / shares	22.25
Vested (in dollars per share) | $ / shares	21.56
Forfeited (in dollars per share) | $ / shares	23.32
Balance at the end of period (in dollars per share) | $ / shares	$ 22.36
Starwood Property Trust, Inc. Equity Plan
Non-Vested Shares and Share Equivalents activity
Balance at the beginning of the period (in shares)	521,336
Granted (in shares)	470,469
Vested (in shares)	(178,136)
Forfeited (in shares)	(12,340)
Balance at the end of the period (in shares)	801,329
Starwood Property Trust, Inc. Manager Equity Plan
Non-Vested Shares and Share Equivalents activity
Balance at the beginning of the period (in shares)	281,250
Granted (in shares)	1,000,000
Vested (in shares)	(56,250)
Balance at the end of the period (in shares)	1,225,000
Starwood Property Trust, Inc. Non-Executive Director Stock Plan
Non-Vested Shares and Share Equivalents activity
Balance at the beginning of the period (in shares)	17,788
Balance at the end of the period (in shares)	17,788