Earnings per Share - Reconciliation of Basic Earnings Per Share to Diluted Earnings Per Share for Income from Continuing Operations (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Earnings Per Share [Abstract]
Basic earnings from continuing operations attributable to Starwood's common stockholders	$ 128		$ 157		$ 137		$ 143		$ 65		$ 147		$ 129		$ 129		$ 565		$ 470		$ 502
Employee options and restricted stock awards
Diluted earnings from continuing operations attributable to Starwood's common stockholders																	$ 565		$ 470		$ 502
Basic earnings from continuing operations attributable to Starwood's common stockholders																	191		193		189
Employee options and restricted stock awards, Shares																	2		4		6
Diluted earnings from continuing operations attributable to Starwood's common stockholders																	193		197		195
Basic earnings from continuing operations attributable to Starwood's common stockholders, Per share	$ 0.68	[1]	$ 0.82	[1]	$ 0.72	[1]	$ 0.74	[1]	$ 0.34	[1]	$ 0.76	[1]	$ 0.67	[1]	$ 0.67	[1]	$ 2.96	[1]	$ 2.44	[1]	$ 2.65
Diluted earnings from continuing operations attributable to Starwood's common stockholders, Per share	$ 0.67	[1]	$ 0.81	[1]	$ 0.71	[1]	$ 0.73	[1]	$ 0.33	[1]	$ 0.75	[1]	$ 0.66	[1]	$ 0.65	[1]	$ 2.92	[1]	$ 2.39	[1]	$ 2.57

[1] Amounts presented are attributable to Starwood's common stockholders.