CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
OPERATING ACTIVITIES
Net income		$ 1,372	$ 780	$ 859
Adjustments to reconcile to cash provided by operating activities:
Depreciation, amortization, and other	[1]	290	168	139
Share-based compensation		181	212	113
Income taxes		828	76	143
Liability for guest loyalty program		378	343	233
Merger-related charges		(124)	113	0
Working capital changes		81	(77)	(41)
(Gain) loss on asset dispositions		(687)	1	(25)
Other		117	66	94
Net cash provided by operating activities		2,436	1,682	1,515
INVESTING ACTIVITIES
Acquisition of a business, net of cash acquired		0	(2,412)	(137)
Capital expenditures		(240)	(199)	(305)
Dispositions		1,418	218	673
Loan advances		(93)	(32)	(66)
Loan collections		187	67	92
Contract acquisition costs		(189)	(80)	(121)
Redemption of debt security		0	0	121
Other		(63)	29	110
Net cash provided by (used in) investing activities		1,020	(2,409)	367
FINANCING ACTIVITIES
Commercial paper/Credit Facility, net		25	1,365	(140)
Issuance of long-term debt		0	1,482	790
Repayment of long-term debt		(310)	(326)	(325)
Issuance of Class A Common Stock		6	34	40
Dividends paid		(482)	(374)	(253)
Purchase of treasury stock		(3,013)	(568)	(1,917)
Share-based compensation withholding taxes		(157)	(100)	(85)
Other		0	(24)	0
Net cash (used in) provided by financing activities		(3,931)	1,489	(1,890)
(DECREASE) INCREASE IN CASH AND EQUIVALENTS		(475)	762	(8)
CASH AND EQUIVALENTS, beginning of period		858	96	104
CASH AND EQUIVALENTS, end of period		$ 383	$ 858	$ 96

[1] See Footnote 19 “Related Party Transactions” for disclosure of related party amounts.