Components of Deferred Tax Assets and Liabilities (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred income tax asset (liability):
Federal and state net operating loss ("NOL") carryforwards	$ 3,491	$ 4,006
Frequent flyer deferred revenue	2,287	2,254
Employee benefits, including pension, postretirement and medical	1,943	1,701
Alternative minimum tax credit carryforwards	214	233
Other	657us-gaap_DeferredTaxAssetsOther	340us-gaap_DeferredTaxAssetsOther
Less: Valuation allowance	(4,751)	(4,591)
Total deferred tax assets	3,841us-gaap_DeferredTaxAssetsNet	3,943us-gaap_DeferredTaxAssetsNet
Depreciation, capitalized interest and other	(3,212)	(3,201)
Intangibles	(1,545)	(1,585)
Other	(84)us-gaap_DeferredTaxLiabilitiesOther	(144)us-gaap_DeferredTaxLiabilitiesOther
Total deferred tax liabilities	(4,841)us-gaap_DeferredTaxLiabilities	(4,930)us-gaap_DeferredTaxLiabilities
Net deferred tax liability	(1,000)us-gaap_DeferredTaxAssetsLiabilitiesNet	(987)us-gaap_DeferredTaxAssetsLiabilitiesNet
United Airlines, Inc.
Deferred income tax asset (liability):
Federal and state net operating loss ("NOL") carryforwards	3,423	3,943
Frequent flyer deferred revenue	2,287	2,254
Employee benefits, including pension, postretirement and medical	1,943	1,701
Alternative minimum tax credit carryforwards	214	233
Other	659	340
Less: Valuation allowance	(4,721)	(4,561)
Total deferred tax assets	3,805	3,910
Depreciation, capitalized interest and other	(3,212)	(3,201)
Intangibles	(1,545)	(1,585)
Other	(48)	(111)
Total deferred tax liabilities	(4,805)	(4,897)
Net deferred tax liability	$ (1,000)	$ (987)

Deferred tax liabilities deferred expense depreciation, capitalized interest and other

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