Types of Temporary Differences and Carry-Forwards that Significantly Effect Deferred Tax Assets and Liabilities (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Employee benefits	$ 347	$ 340
Net operating loss carry-forwards	257	293
Tax credits	182	273
Reserves	55	61
Frequent guest program	47	30
Self-insurance	24	23
Deferred income	20us-gaap_DeferredTaxAssetsDeferredIncome	23us-gaap_DeferredTaxAssetsDeferredIncome
Other, net	16mar_DeferredTaxAssetsLiabilitiesOther	(12)mar_DeferredTaxAssetsLiabilitiesOther
Deferred taxes	948mar_DeferredTaxAssetsLiabilitiesGross	1,031mar_DeferredTaxAssetsLiabilitiesGross
Less: valuation allowance	(145)	(165)
Net deferred taxes	$ 803us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 866us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred Tax Assets, Customer Loyalty Program Liability

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Deferred Tax Assets (Liabilities), Gross

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Deferred Tax Assets (Liabilities), Other

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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The tax effect as of the balance sheet date of the amount of future tax deductions arising from all unused tax credit carryforwards which have been reduced by a valuation allowance.

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-Glossary Carryforwards

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The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from employee benefit costs not otherwise specified in the taxonomy, which can only be deducted for tax purposes when actual costs are incurred, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from other reserves not separately disclosed.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from estimated losses under self insurance.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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