Vacation Ownership Contract Receivables (Allowance For Loan Losses On Vacation Ownership Contract Receivables) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance for Loan Losses on Vaccation Ownership Contract Receivables
Allowance for loan losses, beginning balance	$ 621	$ 581	$ 581
Provision for loan losses	420	342	248
Contract receivables written-off, net	(350)	(302)	(248)
Allowance for loan losses, ending balance	$ 691	$ 621	$ 581

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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