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Income tax reconciliation derivative market adjustment

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Income tax reconciliation goodwill

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Income tax reconciliation nondeductible acquisition costs

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Income tax reconciliation nondeductible interest expense

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Income tax reconciliation tax benefit resulting from intra period tax allocation

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to changes in the valuation allowance for deferred tax assets in the period.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to changes in the income tax rates under enacted tax laws in the period.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to nondeductible expenses under enacted tax laws, or differences in the methodologies used to determine expense amounts for financial statements prepared in accordance with generally accepted accounting principles, not otherwise listed in the existing taxonomy.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to differences in the deductibility of incentive stock options and other equity-based compensation costs in accordance with generally accepted accounting principles and enacted tax laws.

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Income Tax Provision Differed from Amounts Computed at Statutory Federal Income Tax Rate (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended			12 Months Ended						3 Months Ended	12 Months Ended			9 Months Ended	12 Months Ended
	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 United Air Lines Inc	Dec. 31, 2011 United Air Lines Inc	Dec. 31, 2010 United Air Lines Inc	Dec. 31, 2010 Continental Airlines Inc Successor	Dec. 31, 2012 Continental Airlines Inc Successor	Dec. 31, 2011 Continental Airlines Inc Successor	Dec. 31, 2010 Continental Airlines Inc Successor	Sep. 30, 2010 Continental Airlines Inc Predecessor	Dec. 31, 2010 Continental Airlines Inc Predecessor
Income Taxes [Line Items]
Income tax provision at statutory rate				$ (253)	$ 298	$ 87	$ (413)	$ 100	$ 135		$ 183	$ 199	$ (35)		$ 155
State income taxes, net of federal income tax benefit				(15)	(19)	24	(20)	(25)	24		13	8	1		8
Nondeductible acquisition costs					(17)	45		(8)	31			(9)	14
Foreign income taxes				7			6				1
Nondeductible employee meals				12	12	8	7	7	7		5	5	1		3
Nondeductible interest expense				19	13	12	19	13	12
Change in tax law - Medicare Part D Subsidy						119			119
Derivative market adjustment											(15)	10
Nondeductible compensation				5	9	13	3	5	1		2	5	12
Goodwill credit						(22)			(22)
Valuation allowance				234	(294)	(290)	415	(92)	(322)		(192)	(223)	9		(166)
Tax benefit resulting from intraperiod tax allocation													(6)
Other, net				(10)	3	4	(8)	3	3		(2)	(1)			1
Income tax benefit	$ (9)	$ (2)	$ (2)	$ (1)	$ 5		$ 9	$ 3	$ (12)	$ (4)	$ (5)	$ (6)	$ (4)	$ 1	$ 1