Vacation Ownership Notes Receivable - Balances of VOI Notes Receivable by Brand and by FICO Score (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Accounts Notes And Loans Receivable [Line Items]
Total receivables	$ 693	$ 701
Sheraton [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	376	368
Westin [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	303	316
Other [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	14	17
700+ [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	347	352
700+ [Member] | Sheraton [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	161	157
700+ [Member] | Westin [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	178	186
700+ [Member] | Other [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	8	9
600-699 [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	233	224
600-699 [Member] | Sheraton [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	142	134
600-699 [Member] | Westin [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	89	88
600-699 [Member] | Other [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	2	2
Less than 600 [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	19	21
Less than 600 [Member] | Sheraton [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	14	15
Less than 600 [Member] | Westin [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	5	6
No Score [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	94	104
No Score [Member] | Sheraton [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	59	62
No Score [Member] | Westin [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	31	36
No Score [Member] | Other [Member]
Accounts Notes And Loans Receivable [Line Items]
Total receivables	$ 4	$ 6