Stockholders' Equity - Equity Attributable to Starwood's Stockholders (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2014	Mar. 31, 2013
Schedule Of Stockholders Equity [Line Items]
Beginning Balance		$ 3,363
Net income		137	213
Equity compensation activity and other		14
Dividends	(190)	(194)
Other comprehensive income (loss)			(13)
Ending Balance	3,320	3,320
Common Shares [Member]
Schedule Of Stockholders Equity [Line Items]
Beginning Balance		2
Net income
Equity compensation activity and other
Dividends
Other comprehensive income (loss)
Ending Balance	2	2
Additional Paid-in Capital [Member]
Schedule Of Stockholders Equity [Line Items]
Beginning Balance		661
Net income
Equity compensation activity and other		14
Dividends
Other comprehensive income (loss)
Ending Balance	675	675
Accumulated Other Comprehensive Loss [Member]
Schedule Of Stockholders Equity [Line Items]
Beginning Balance		(335)
Net income
Equity compensation activity and other
Dividends
Other comprehensive income (loss)
Ending Balance	(335)	(335)
Retained Earnings [Member]
Schedule Of Stockholders Equity [Line Items]
Beginning Balance		3,032
Net income		137
Equity compensation activity and other
Dividends		(194)
Other comprehensive income (loss)
Ending Balance	2,975	2,975
Equity Attributable to Noncontrolling Interests [Member]
Schedule Of Stockholders Equity [Line Items]
Beginning Balance		3
Net income
Equity compensation activity and other
Dividends
Other comprehensive income (loss)
Ending Balance	$ 3	$ 3