Asset Dispositions and Impairments - Additional Information (Detail) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($) Hotel	Jun. 30, 2015 USD ($) Hotel	Jun. 30, 2016 USD ($) Hotel	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from asset sales, net			$ 390	$ 527
Cumulative translation adjustment loss			(202)
Deferred gains on dispositions of assets	$ 1,381		1,381		$ 1,412
Gain on disposition of assets			2
Gain (loss) on asset dispositions and impairments, net	(114)		(112)	14
Long-term management agreements [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from asset sales, net			$ 79
Number of wholly-owned hotels sold | Hotel			1
Sale of Minority Partnership Interest [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain (loss) on asset dispositions and impairments, net				(3)
Gain related to sale of a minority partnership interest				17
Two foreign wholly-owned hotels [Member] | Long-term management agreements [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from asset sales, net	206
Cumulative translation adjustment loss	$ (202)
Number of wholly-owned hotels sold | Hotel	2
Two foreign wholly-owned hotels [Member] | Long-term management agreements [Member] | Italy [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Pre-tax gain (loss) on sale of assets and asset impairment charges	$ 112
One wholly-owned hotel [Member] | Long-term management agreements [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Deferred gains on dispositions of assets	$ 5		$ 5
One wholly-owned hotel [Member] | Long-term franchise agreements [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Pre-tax gain (loss) on sale of assets and asset impairment charges		$ 4
Number of wholly-owned hotels sold | Hotel		1
Gain (loss) on asset dispositions and impairments, net		$ 4
Three wholly-owned hotels [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from asset sales, net		$ 527
Number of wholly-owned hotels sold | Hotel		3
Two wholly-owned hotels [Member] | Long-term management agreements [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of wholly-owned hotels sold | Hotel		2
Deferred gains on dispositions of assets		$ 240		$ 240