Segment Information - Revenues and Segment Earnings (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Segment Reporting Information [Line Items]
Total revenues	$ 1,246	$ 1,241	$ 2,390	$ 2,400
Other revenues from managed and franchised hotels	680	653	1,333	1,281
Corporate selling, general, administrative and other expenses — unallocated	(93)	(99)	(179)	(190)
Gain (loss) on asset dispositions and impairments, net	(114)		(112)	14
Restructuring and other special (charges) credits	(16)	(12)	(48)	(37)
Adjustments to equity earnings	(8)	(7)	(16)	(12)
Interest expense	(26)	(27)	(48)	(56)
Depreciation and amortization	(60)	(63)	(120)	(123)
Income tax expense	(87)	(33)	(118)	(69)
Discontinued operations	(228)	18	(211)	42
Net income (loss) attributable to Starwood	(263)	136	(173)	235
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues	527	560	992	1,066
Total segment earnings	272	272	502	505
Operating Segments [Member] | Americas Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	344	360	655	703
Total segment earnings	178	177	331	335
Operating Segments [Member] | EAME [Member]
Segment Reporting Information [Line Items]
Total revenues	114	133	200	231
Total segment earnings	52	51	81	80
Operating Segments [Member] | Asia Pacific Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	69	67	137	132
Total segment earnings	42	44	90	90
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Other revenues from managed and franchised hotels	680	653	1,333	1,281
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	39	28	65	53
Other corporate income — unallocated	37	29	65	55
Corporate selling, general, administrative and other expenses — unallocated	$ (33)	$ (41)	$ (67)	$ (84)