United Airlines 10-Q 24 Oct 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2013	Oct. 15, 2013
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	30-Sep-13
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q3
Trading Symbol	UAL
Entity Registrant Name	United Continental Holdings, Inc.
Entity Central Index Key	100517
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		361,871,592
United Airlines, Inc.
Document Information [Line Items]
Entity Registrant Name	United Airlines, Inc.
Entity Central Index Key	319687
Current Fiscal Year End Date	-19
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		1,000

Statements_of_Consolidated_Ope

Statements of Consolidated Operations (USD $)	3 Months Ended		9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Operating revenue:
Passenger-Mainline	$7,025	$6,993	$19,792	$19,891
Passenger-Regional	1,893	1,781	5,353	5,159
Total passenger revenue	8,918	8,774	25,145	25,050
Cargo	199	246	662	775
Other operating revenue	1,111	889	3,143	2,625
Total revenue	10,228	9,909	28,950	28,450
Operating expense:
Aircraft fuel	3,262	3,406	9,380	10,043
Salaries and related costs	2,209	2,038	6,511	5,959
Regional capacity purchase	621	628	1,837	1,887
Landing fees and other rent	540	504	1,544	1,476
Aircraft maintenance materials and outside repairs	472	469	1,390	1,308
Depreciation and amortization	435	379	1,268	1,137
Distribution expenses	377	356	1,052	1,038
Aircraft rent	231	245	706	747
Special charges	211	514	355	884
Other operating expenses	1,362	1,170	3,893	3,467
Total operating expenses	9,720	9,709	27,936	27,946
Operating income	508	200	1,014	504
Nonoperating income (expense):
Interest expense	-195	-202	-590	-631
Interest capitalized	12	9	35	26
Interest income	5	4	16	16
Miscellaneous, net	52	4	-48	-7
Total other income (expense)	-126	-185	-587	-596
Income (loss) before income taxes	382	15	427	-92
Income tax expense (benefit)	3	9	-4	11
Net income (loss)	379	6	431	-103
Earnings (loss) per share, basic	$1.06	$0.02	$1.25	($0.31)
Earnings (loss) per share, diluted	$0.98	$0.02	$1.15	($0.31)
United Airlines, Inc.
Operating revenue:
Passenger-Mainline	7,025	6,993	19,792	19,891
Passenger-Regional	1,893	1,781	5,353	5,159
Total passenger revenue	8,918	8,774	25,145	25,050
Cargo	199	246	662	775
Other operating revenue	1,113	893	3,149	2,632
Total revenue	10,230	9,913	28,956	28,457
Operating expense:
Aircraft fuel	3,262	3,406	9,380	10,043
Salaries and related costs	2,209	2,038	6,511	5,959
Regional capacity purchase	621	628	1,837	1,887
Landing fees and other rent	540	504	1,544	1,476
Aircraft maintenance materials and outside repairs	472	469	1,390	1,308
Depreciation and amortization	435	379	1,268	1,137
Distribution expenses	377	356	1,052	1,038
Aircraft rent	231	245	706	747
Special charges	211	514	355	884
Other operating expenses	1,362	1,170	3,892	3,465
Total operating expenses	9,720	9,709	27,935	27,944
Operating income	510	204	1,021	513
Nonoperating income (expense):
Interest expense	-195	-204	-586	-637
Interest capitalized	12	9	35	26
Interest income	5	4	16	16
Miscellaneous, net	50	-29	18	6
Total other income (expense)	-128	-220	-517	-589
Income (loss) before income taxes	382	-16	504	-76
Income tax expense (benefit)	4	9	4	11
Net income (loss)	$378	($25)	$500	($87)

Statements_of_Consolidated_Com

Statements of Consolidated Comprehensive Income (Loss) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net income (loss)	$379	$6	$431	($103)
Other comprehensive income, net:
Net change related to fuel derivative financial instruments	30	171	20	71
Net change related to employee benefit plans	51	4	531	13
Net change related to investments and other	-5	5	2	14
Comprehensive income (loss) adjustments, before tax	76	180	553	98
Total comprehensive income (loss), net	455	186	984	-5
United Airlines, Inc.
Net income (loss)	378	-25	500	-87
Other comprehensive income, net:
Net change related to fuel derivative financial instruments	30	171	20	71
Net change related to employee benefit plans	51	4	531	13
Net change related to investments and other	-5	6	3	15
Other			6
Comprehensive income (loss) adjustments, before tax	76	181	560	99
Total comprehensive income (loss), net	$454	$156	$1,060	$12

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Current assets:
Cash and cash equivalents	$3,935	$4,770
Short-term investments	1,801	1,773
Total unrestricted cash, cash equivalents and short-term investments	5,736	6,543
Restricted cash	46	65
Receivables, less allowance for doubtful accounts	1,693	1,338
Aircraft fuel, spare parts and supplies, less obsolescence allowance	646	695
Deferred income taxes	568	543
Prepaid expenses and other	700	865
Total current assets	9,389	10,049
Operating property and equipment: Owned-
Flight equipment	18,486	17,561
Other property and equipment	3,474	3,269
Operating property and equipment - owned, gross	21,960	20,830
Less - Accumulated depreciation and amortization	-5,846	-5,006
Operating property and equipment - owned, net	16,114	15,824
Purchase deposits for flight equipment	674	462
Capital leases-
Flight equipment	1,483	1,484
Other property and equipment	306	235
Operating property and equipment - capital leases, gross	1,789	1,719
Less - Accumulated amortization	-811	-713
Operating property and equipment - capital leases, net	978	1,006
Total property, plant, and equipment, net	17,766	17,292
Other assets:
Goodwill	4,523	4,523
Intangibles, less accumulated amortization	4,487	4,597
Restricted cash	366	382
Other, net	729	785
Other assets total	10,105	10,287
Total assets	37,260	37,628
Current liabilities:
Advance ticket sales	4,123	3,360
Frequent flyer deferred revenue	2,378	2,364
Accounts payable	2,126	2,312
Accrued salaries and benefits	1,844	1,763
Current maturities of long-term debt	957	1,812
Current maturities of capital leases	117	122
Other	1,059	1,085
Total current liabilities	12,604	12,818
Long-term debt	10,204	10,440
Long-term obligations under capital leases	781	792
Other liabilities and deferred credits:
Frequent flyer deferred revenue	2,556	2,756
Postretirement benefit liability	2,653	2,614
Pension liability	1,803	2,400
Advanced purchase of miles	1,388	1,537
Deferred income taxes	1,573	1,543
Lease fair value adjustment, net	672	881
Other	1,298	1,366
Total non-current liabilities	11,943	13,097
Commitments and contingencies
Stockholder's equity:
Preferred stock
Common stock	4	3
Additional capital invested	7,410	7,145
Accumulated deficit	-5,155	-5,586
Stock held in treasury, at cost	-38	-35
Accumulated other comprehensive loss	-493	-1,046
Total stockholders' equity	1,728	481
Total liabilities and stockholders' equity (deficit)	37,260	37,628
United Airlines, Inc.
Current assets:
Cash and cash equivalents	3,928	4,765
Short-term investments	1,801	1,773
Total unrestricted cash, cash equivalents and short-term investments	5,729	6,538
Restricted cash	46	65
Receivables from related parties	231	226
Receivables, less allowance for doubtful accounts	1,693	1,338
Aircraft fuel, spare parts and supplies, less obsolescence allowance	646	695
Deferred income taxes	578	546
Prepaid expenses and other	685	841
Total current assets	9,608	10,249
Operating property and equipment: Owned-
Flight equipment	18,486	17,561
Other property and equipment	3,474	3,269
Operating property and equipment - owned, gross	21,960	20,830
Less - Accumulated depreciation and amortization	-5,846	-5,006
Operating property and equipment - owned, net	16,114	15,824
Purchase deposits for flight equipment	674	462
Capital leases-
Flight equipment	1,483	1,484
Other property and equipment	306	235
Operating property and equipment - capital leases, gross	1,789	1,719
Less - Accumulated amortization	-811	-713
Operating property and equipment - capital leases, net	978	1,006
Total property, plant, and equipment, net	17,766	17,292
Other assets:
Goodwill	4,523	4,523
Intangibles, less accumulated amortization	4,487	4,597
Restricted cash	365	382
Other, net	1,104	1,052
Other assets total	10,479	10,554
Total assets	37,853	38,095
Current liabilities:
Advance ticket sales	4,123	3,360
Frequent flyer deferred revenue	2,378	2,364
Accounts payable	2,131	2,316
Accrued salaries and benefits	1,844	1,763
Current maturities of long-term debt	957	1,812
Current maturities of capital leases	117	122
Payables to related parties	42	75
Other	1,120	1,140
Total current liabilities	12,712	12,952
Long-term debt	10,051	10,038
Long-term obligations under capital leases	781	792
Other liabilities and deferred credits:
Frequent flyer deferred revenue	2,556	2,756
Postretirement benefit liability	2,653	2,614
Pension liability	1,803	2,400
Advanced purchase of miles	1,388	1,537
Deferred income taxes	1,508	1,470
Lease fair value adjustment, net	672	881
Other	1,483	1,494
Total non-current liabilities	12,063	13,152
Commitments and contingencies
Stockholder's equity:
Additional capital invested	7,636	7,611
Accumulated deficit	-4,897	-5,397
Accumulated other comprehensive loss	-493	-1,053
Total stockholders' equity	2,246	1,161
Total liabilities and stockholders' equity (deficit)	$37,853	$38,095

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, except Share data, unless otherwise specified
Receivables, allowance for doubtful accounts	$16	$13
Aircraft fuel, spare parts and supplies, obsolescence allowance	157	125
Intangibles, accumulated amortization	900	792
Common stock, par value	$0.01	$0.01
Common shares, authorized	1,000,000,000	1,000,000,000
Common shares, outstanding	361,871,040	332,472,779
United Airlines, Inc.
Receivables, allowance for doubtful accounts	16	13
Aircraft fuel, spare parts and supplies, obsolescence allowance	157	125
Intangibles, accumulated amortization	$900	$792
Common stock, par value	$0.01	$0.01
Common shares, authorized	1,000	1,000
Common shares, issued	1,000	1,000
Common shares, outstanding	1,000	1,000

Condensed_Statements_of_Consol

Condensed Statements of Consolidated Cash Flows (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Cash Flows from Operating Activities:
Net cash provided by operating activities	$1,778	$845
Cash Flows from Investing Activities:
Capital expenditures and aircraft purchase deposits paid	-1,399	-1,027
Proceeds from sale of property and equipment	65	146
Decrease in restricted cash, net	35	98
Increase in short-term and other investments, net	-22	-22
Other, net	22
Net cash used in investing activities	-1,299	-805
Cash Flows from Financing Activities:
Payments of long-term debt	-1,965	-1,158
Proceeds from issuance of long-term debt	819	86
Principal payments under capital leases	-98	-89
Other, net	-70	4
Net cash used in financing activities	-1,314	-1,157
Net decrease in cash and cash equivalents	-835	-1,117
Cash and cash equivalents at beginning of the period	4,770	6,246
Cash and cash equivalents at end of the period	3,935	5,129
Investing and Financing Activities Not Affecting Cash:
Exchanges of certain 6% convertible senior notes for common stock (Note 3)	240
Net property and equipment acquired through the issuance of debt	239	526
Special facility and airport construction financing	35	132
8% Contingent Senior Unsecured Notes, net of discount		48
United Airlines, Inc.
Cash Flows from Operating Activities:
Net cash provided by operating activities	1,774	844
Cash Flows from Investing Activities:
Capital expenditures and aircraft purchase deposits paid	-1,399	-1,027
Proceeds from sale of property and equipment	65	146
Decrease in restricted cash, net	36	98
Increase in short-term and other investments, net	-22	-22
Other, net	20
Net cash used in investing activities	-1,300	-805
Cash Flows from Financing Activities:
Payments of long-term debt	-1,965	-1,158
Proceeds from issuance of long-term debt	819	86
Principal payments under capital leases	-98	-89
Other, net	-67	6
Net cash used in financing activities	-1,311	-1,155
Net decrease in cash and cash equivalents	-837	-1,116
Cash and cash equivalents at beginning of the period	4,765	6,240
Cash and cash equivalents at end of the period	3,928	5,124
Investing and Financing Activities Not Affecting Cash:
Net property and equipment acquired through the issuance of debt	239	526
Special facility and airport construction financing	35	132
8% Contingent Senior Unsecured Notes, net of discount		$48

Condensed_Statements_of_Consol1

Condensed Statements of Consolidated Cash Flows (Parenthetical)	Sep. 30, 2013	Sep. 30, 2012
Debt instrument stated interest rate	8.00%	8.00%
6% Convertible Senior Notes
Debt instrument stated interest rate	6.00%	6.00%
United Airlines, Inc.
Debt instrument stated interest rate	8.00%	8.00%

FREQUENT_FLYER_ACCOUNTING

FREQUENT FLYER ACCOUNTING	9 Months Ended
	Sep. 30, 2013
FREQUENT FLYER ACCOUNTING	NOTE 1—FREQUENT FLYER ACCOUNTING
	Frequent Flyer Awards. The Company revised the estimated selling price of miles as a prospective change in estimate, effective January 1, 2012, based on the price at which the Company sells miles to Star Alliance partners in its reciprocal frequent flyer agreements as the best estimate of the selling price for these miles. Any changes to the composition of Star Alliance airline partners could result in a change to the amount and method we use to determine the estimated selling price. On February 14, 2013, US Airways Group, Inc. announced an agreement to merge with AMR Corporation and its intent to exit Star Alliance as a result of such merger. The Department of Justice has challenged the proposed merger. If the merger ultimately occurs, it could impact our estimated selling price of miles.

NEW_ACCOUNTING_PRONOUNCEMENTS

NEW ACCOUNTING PRONOUNCEMENTS	9 Months Ended
	Sep. 30, 2013
NEW ACCOUNTING PRONOUNCEMENTS	NOTE 2—NEW ACCOUNTING PRONOUNCEMENTS
	In February 2013, the Financial Accounting Standards Board issued Accounting Standards Update No. 2013-02 (“ASU 2013-02”), Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income. Some of the key amendments require the Company to present, either on the face of the statement of operations or in the notes, the effects on the line items of net income of significant amounts reclassified out of accumulated other comprehensive income, but only if the amount reclassified is required under U.S. GAAP to be reclassified to net income in its entirety in the same reporting period. For amounts that are not required to be reclassified in their entirety to net income, the Company is required to cross-reference to other disclosures that provide additional detail about those amounts. ASU 2013-02 became effective for the Company’s annual and interim periods beginning January 1, 2013, and the required disclosures are included in Note 11 of this report.

EARNINGS_LOSS_PER_SHARE

EARNINGS (LOSS) PER SHARE	9 Months Ended
	Sep. 30, 2013
EARNINGS (LOSS) PER SHARE	NOTE 3—EARNINGS (LOSS) PER SHARE
	The table below represents the computation of UAL’s basic and diluted earnings (loss) per share amounts and the number of securities that have been excluded from the computation of diluted earnings (loss) per share amounts because they were antidilutive (in millions, except per share amounts):
		Three Months Ended					Nine Months Ended
		September 30,					September 30,
		2013			2012		2013			2012
	Basic earnings (loss) per share:
	Net income (loss)	$	379		$	6	$	431		$	(103	)
	Less: Income allocable to participating securities		(1	)		—		(1	)		—
	Earnings (loss) available to common stockholders	$	378		$	6	$	430		$	(103	)
	Basic weighted average shares outstanding		357			331		343			331
	Earnings (loss) per share, basic	$	1.06		$	0.02	$	1.25		$	(0.31	)
	Diluted earnings (loss) per share:
	Earnings (loss) available to common stockholders	$	378		$	6	$	430		$	(103	)
	Effect of convertible notes		9			—		20			—
	Earnings (loss) available to common stockholders including the effect of dilutive securities	$	387		$	6	$	450		$	(103	)
	Diluted shares outstanding:
	Basic weighted-average shares outstanding		357			331		343			331
	Effect of convertible notes		37			—		46			—
	Effect of employee stock options		1			1		1			—
	Diluted weighted-average shares outstanding		395			332		390			331
	Earnings (loss) per share, diluted	$	0.98		$	0.02	$	1.15		$	(0.31	)
	Potentially dilutive shares excluded from diluted per share amounts:
	Restricted stock and stock options		3			5		3			6
	Convertible notes		—			61		4			61
	During the three and nine months ended September 30, 2013, UAL issued approximately 6 million and 28 million shares, respectively, of UAL common stock pursuant to agreements that UAL entered into with certain of its securityholders in exchange for approximately $51 million and $240 million, respectively, in aggregate principal amount of UAL’s outstanding 6% convertible senior notes due 2029 held by such securityholders. The newly issued shares of UAL common stock are included in the determination of basic weighted average shares outstanding for the three and nine months ended September 30, 2013 from the date the shares were issued. The Company retired the 6% convertible senior notes acquired in the exchange.

INCOME_TAXES

INCOME TAXES	9 Months Ended
	Sep. 30, 2013
INCOME TAXES	NOTE 4—INCOME TAXES
	Our effective tax rates are lower than the federal statutory rate of 35% primarily because of the impact of changes to existing valuation allowances. We continue to provide a valuation allowance for our deferred tax assets in excess of deferred tax liabilities because we have concluded that it is more likely than not that such deferred tax assets will ultimately not be realized.
	United files a consolidated federal income tax return with UAL. Under an intercompany tax allocation policy, United computes, records and pays UAL for its own tax liability as if United were a separate company filing a separate return. In determining its own tax liabilities, United takes into account all tax credits or benefits generated and utilized as a separate company and it is compensated for the aforementioned tax benefits only if it would be able to use those benefits on a separate company basis.

EMPLOYEE_BENEFIT_PLANS

EMPLOYEE BENEFIT PLANS	9 Months Ended
	Sep. 30, 2013
EMPLOYEE BENEFIT PLANS	NOTE 5—EMPLOYEE BENEFIT PLANS
	Defined Benefit Pension and Other Postretirement Benefit Plans. The Company’s net periodic benefit cost includes the following components (in millions):
			Pension Benefits						Other Postretirement Benefits
			Three Months Ended						Three Months Ended
			September 30,						September 30,
			2013			2012			2013			2012
	Service cost		$	29		$	25		$	14		$	11
	Interest cost			48			45			29			30
	Expected return on plan assets			(41	)		(33	)		(1	)		—
	Amortization of unrecognized loss and prior service			8			4			2			—
	cost
	Curtailment loss			—			—			—			—
	Settlement gain			(1	)		—			—			—
	Total		$	43		$	41		$	44		$	41
			Pension Benefits						Other Postretirement Benefits
			Nine Months Ended						Nine Months Ended
			September 30,						September 30,
			2013			2012			2013			2012
	Service cost		$	94		$	75		$	42		$	37
	Interest cost			142			137			85			93
	Expected return on plan assets			(121	)		(103	)		(2	)		(2	)
	Amortization of unrecognized (gain) loss and prior service			41			15			7			(2	)
	cost
	Curtailment loss			2			—			—			—
	Settlement gain			(2	)		—			—			—
	Total		$	156		$	124		$	132		$	126
	During the three and nine months ended September 30, 2013, the Company contributed $122 million and $201 million, respectively, to its tax-qualified defined benefit pension plans.
	Curtailments, Settlements and Plan Remeasurements. During June 2013, the Company announced it would freeze benefits for management and administrative employees under one of its defined benefit pension plans, effective December 31, 2013. As a result, the Company recognized a $2 million curtailment loss in earnings in second quarter 2013. The Company also recognized a settlement gain of $1 million in earnings resulting from certain lump-sum payments under a separate defined benefit pension plan in second quarter 2013.
	As a result of the freeze of benefits for management and administrative employees and the settlements from the lump-sum payments, the Company remeasured the assets and liabilities of the two plans in second quarter 2013. In addition, due to additional lump-sum payments, the Company remeasured the assets and liabilities of the defined benefit pension plan and recognized a settlement gain of $1 million in third quarter 2013. The Company remeasured this plan’s liabilities using a discount rate of 4.59% in the second quarter and 5.13% in the third quarter compared to the year-end 2012 discount rate of 4.20%. During the nine months ended September 30, 2013, as a result of the remeasurements, curtailment and settlements, the projected benefit obligation of the plans decreased by $522 million and Other comprehensive loss decreased by an actuarial gain of $41 million and $483 million for the three and nine months ended September 30, 2013, respectively. These items will also result in a decrease of approximately $13 million in the expected net periodic benefit cost for the remainder of 2013. The Company recognizes the earnings impacts of its pension plans in Salaries and related costs in the statements of consolidated operations.
	Share-Based Compensation. In February 2013, UAL granted share-based compensation awards pursuant to the United Continental Holdings, Inc. 2008 Incentive Compensation Plan. These share-based compensation awards include approximately 0.5 million shares of restricted stock and 0.5 million restricted stock units (“RSUs”) that vest pro-rata over three years on the anniversary of the grant date. The time-vested RSUs are cash-settled based on the 20-day average closing price of UAL common stock immediately prior to the vesting date. In addition, the Company granted 1.3 million performance-based RSUs that will vest based on the Company’s return on invested capital for the three years ending December 31, 2015. If this performance condition is achieved, cash payments will be made after the end of the performance period based on the 20-day average closing price of UAL common stock immediately prior to the vesting date. The Company accounts for the RSUs as liability awards. The table below presents information related to share-based compensation (in millions):
			Three Months Ended						Nine Months Ended
			September 30,						September 30,
			2013			2012			2013			2012
	Share-based compensation expense (a)		$	32		$	18		$	72		$	44
			September 30, 2013			December 31, 2012
	Unrecognized share-based compensation		$	55		$	33
	(a)	Includes $(2) million and $9 million of (benefit) expense recognized in merger integration-related costs for the three and nine months ended September 30, 2013, respectively. Includes $0 and $7 million of expense recognized in merger integration-related costs for the three and nine months ended September 30, 2012, respectively.
	Profit Sharing Plans. A majority of all employees participate in profit sharing plans, which pay 15% of total pre-tax earnings, excluding special items and share-based compensation expense, to eligible employees when pre-tax profit, excluding special items, profit sharing expense and share-based compensation program expense, exceeds $10 million. Eligible U.S. co-workers in each participating work group receive a profit sharing payout using a formula based on the ratio of each qualified co-worker’s annual eligible earnings to the eligible earnings of all qualified co-workers in all domestic workgroups. The international profit sharing plan pays eligible non-U.S. co-workers the same percentage of eligible pay that is calculated under the U.S. profit sharing plan. Profit sharing expense is recorded as a component of salaries and related costs in the consolidated statements of operations. Our profit sharing plan will change in 2014. Beginning with 2014, pilots’ share of profit sharing payments will be limited to an amount that is their pro-rata share of 10% of the Company’s profit up to a pre-tax margin of 6.9% and their pro-rata share of 20% of the Company’s profit in excess of a pre-tax margin of 6.9%. The profit sharing plan is otherwise unchanged.

FINANCIAL_INSTRUMENTS_AND_FAIR

FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS	9 Months Ended
	Sep. 30, 2013
FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS	NOTE 6—FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS
	The table below presents disclosures about the financial assets and financial liabilities measured at fair value on a recurring basis in the Company’s financial statements (in millions):
			September 30, 2013												December 31, 2012
			Total			Level 1			Level 2			Level 3			Total			Level 1			Level 2			Level 3
			UAL
	Cash and cash equivalents		$	3,935		$	3,935		$	—		$	—		$	4,770		$	4,770		$	—		$	—
	Short-term investments:
	Asset-backed securities			683			—			683			—			715			—			715			—
	Corporate debt			581			—			581			—			537			—			537			—
	Certificates of deposit placed through an account registry service (“CDARS”)			308			—			308			—			367			—			367			—
	Auction rate securities			104			—			—			104			116			—			—			116
	Other short-term investments			125			—			125			—			38			—			38			—
	Enhanced equipment trust certificates (“EETC”)			59			—			—			59			63			—			—			63
	Fuel derivative asset (liability), net			52			—			52			—			46			—			46			—
	Restricted cash			412			412			—			—			447			447			—			—
			United
	Cash and cash equivalents		$	3,928		$	3,928		$	—		$	—		$	4,765		$	4,765		$	—		$	—
	Short-term investments:
	Asset-backed securities			683			—			683			—			715			—			715			—
	Corporate debt			581			—			581			—			537			—			537			—
	CDARS			308			—			308			—			367			—			367			—
	Auction rate securities			104			—			—			104			116			—			—			116
	Other short-term investments			125			—			125			—			38			—			38			—
	EETC			59			—			—			59			63			—			—			63
	Fuel derivative asset (liability), net			52			—			52			—			46			—			46			—
	Restricted cash			411			411			—			—			447			447			—			—
	Convertible debt derivative asset			376			—			—			376			268			—			—			268
	Convertible debt option liability			(185	)		—			—			(185	)		(128	)		—			—			(128	)
	Available-for-sale investment maturities—The short-term investments and EETC securities shown in the table above are classified as available-for-sale. Short-term investments have maturities of less than one year except for asset-backed securities, corporate debt and auction rate securities. As of September 30, 2013, asset-backed securities have remaining maturities of approximately one to 42 years, corporate debt securities have remaining maturities of approximately one to 22 years, and auction rate securities have remaining maturities of approximately one to 33 years. The EETC securities have various maturities with the final maturity in 2019.
	The tables below present disclosures about the activity for “Level 3” financial assets and financial liabilities (in millions):
			Three Months Ended September 30,
			2013						2012
	UAL		Auction Rate			EETC			Auction Rate			EETC
			Securities						Securities
	Balance at June 30		$	115		$	62		$	112		$	63
	Settlements			(9	)		(2	)		—			(2	)
	Gains (losses):
	Reported in earnings—realized			1			—			—			—
	Reported in earnings—unrealized			—			—			1			—
	Reported in other comprehensive income (loss)			(3	)		(1	)		2			1
	Balance at September 30		$	104		$	59		$	115		$	62
			Nine Months Ended September 30,
			2013						2012
	UAL		Auction Rate			EETC			Auction Rate			EETC
			Securities						Securities
	Balance at January 1		$	116		$	63		$	113		$	60
	Settlements			(19	)		(4	)		—			(5	)
	Gains (losses):
	Reported in earnings—realized			3			—			—			—
	Reported in earnings—unrealized			1			—			—			7
	Reported in other comprehensive income (loss)			3			—			2			—
	Balance at September 30		$	104		$	59		$	115		$	62
			Three Months Ended September 30,
			2013												2012
	United		Auction			Convertible			Convertible			EETC			Auction			Convertible			Convertible			EETC
			Rate			Debt			Debt						Rate			Debt			Debt
			Securities			Supplemental			Conversion						Securities			Supplemental			Conversion
						Derivative			Option									Derivative			Option
						Asset			Liability									Asset			Liability
	Balance at June 30		$	115		$	395		$	(199	)	$	62		$	112		$	289		$	(147	)	$	63
	Settlements			(9	)		—			—			(2	)		—			—			—			(2	)
	Gains (losses):
	Reported in earnings:
	Realized			1			—			—			—			—			—			—			—
Unrealized			—			(19	)		14			—			1			(87	)		56			—
Reported in other comprehensive income (loss)			(3	)		—			—			(1	)		2			—			—			1
Balance at September 30		$	104		$	376		$	(185	)	$	59		$	115		$	202		$	(91	)	$	62
		Nine Months Ended September 30,
		2013												2012
United		Auction			Convertible			Convertible			EETC			Auction			Convertible			Convertible			EETC
		Rate			Debt			Debt						Rate			Debt			Debt
		Securities			Supplemental			Conversion						Securities			Supplemental			Conversion
					Derivative			Option									Derivative			Option
					Asset			Liability									Asset			Liability
Balance at January 1		$	116		$	268		$	(128	)	$	63		$	113		$	193		$	(95	)	$	60
Settlements			(19	)		—			—			(4	)		—			—			—			(5	)
Gains (losses):
Reported in earnings:
Realized			3			—			—			—			—			—			—			—
Unrealized			1			108			(57	)		—			—			9			4			7
Reported in other comprehensive income (loss)			3			—			—			—			2			—			—			—
Balance at September 30		$	104		$	376		$	(185	)	$	59		$	115		$	202		$	(91	)	$	62
As of September 30, 2013, the Company’s auction rate securities, which had a par value of $115 million, were variable-rate debt instruments with interest rates that reset every 7, 28 or 35 days, depending on the terms of the particular instrument. These securities are backed by pools of student loans guaranteed by state-designated guaranty agencies and reinsured by the U.S. government. All of the auction rate securities that the Company holds are senior obligations under the applicable indentures authorizing the issuance of the securities.
As of September 30, 2013, United’s EETC securities, which were repurchased in open market transactions in 2007, have unrealized gains of $2 million. All changes in the fair value of these investments have been classified within accumulated other comprehensive income.
United’s debt-related derivatives presented in the tables above relate to (a) supplemental indenture agreements that provide that United’s convertible debt is convertible into shares of UAL common stock upon the terms and conditions specified in the indentures, and (b) the embedded conversion options in United’s convertible debt that are required to be separated and accounted for as though they are free-standing derivatives as a result of the United debt becoming convertible into the common stock of a different reporting entity. The derivatives described above relate to the 6% convertible junior subordinated debentures due 2030 and the 4.5% convertible notes due 2015. These derivatives are reported in United’s separate financial statements and eliminated in consolidation for UAL.
Derivative instruments and investments presented in the tables above have the same fair value as their carrying value. The table below presents the carrying values and estimated fair values of financial instruments not presented in the tables above (in millions):
Fair Value of Debt by Fair Value Hierarchy Level
		September 30, 2013															December 31, 2012
		Carrying			Fair Value												Carrying			Fair Value
		Amount															Amount
					Total			Level 1			Level 2			Level 3						Total			Level 1			Level 2		Level 3
UAL debt		$	11,161		$	12,036		$	—		$	7,428		$	4,608		$	12,252		$	13,419		$	—		$	8,045	$	5,374
United debt			11,008			11,651			—			7,043			4,608			11,850			12,460			—			7,086		5,374
Quantitative Information About Level 3 Fair Value Measurements (in millions)
Item		Fair Value at			Valuation		Unobservable Input	Range (Weighted
		September 30, 2013			Technique			Average)
Auction rate securities		$	104		Valuation Service / Broker Quotes		Broker quotes (a)	NA
EETC		$	59		Discounted Cash Flows		Structure credit risk (b)	5% - 6%(6%)
Convertible debt derivative asset		$	376		Binomial Lattice Model		Expected volatility (c)	45% - 60%(47%)
							Own credit risk (d)	5% - 6%(5%)
Convertible debt option liability		$	(185	)	Binomial Lattice Model		Expected volatility (c)	45% - 60%(47%)
							Own credit risk (d)	5% - 6%(5%)
(a)	Broker quotes obtained by a third-party valuation service.
(b)	Represents the credit risk premium of the EETC structure above the risk-free rate that the Company has determined market participants would use in pricing the instruments.
(c)	Represents the range in volatility estimates that the Company has determined market participants would use when pricing the instruments.
(d)	Represents the range of Company-specific risk adjustments that the Company has determined market participants would use as a model input.
Valuation Processes—Level 3 Measurements—Depending on the instrument, the Company utilizes broker quotes obtained from third-party valuation services, discounted cash flow methods, or option pricing methods, as indicated above. Valuations using discounted cash flow methods are generally conducted by the Company. Valuations using option pricing models are generally provided to the Company by third-party valuation experts. Each reporting period, the Company reviews the unobservable inputs used by third-party valuation experts for reasonableness utilizing relevant information available to the Company from other sources.
The Company uses broker quotes obtained from a valuation service (in replacement of a discounted cash flows method) for valuing auction rate securities. This approach provides the best available information.
Sensitivity Analysis—Level 3 Measurements—Changes in the structure credit risk would be unlikely to cause material changes in the fair value of the EETCs.
The significant unobservable inputs used in the fair value measurement of the United convertible debt derivative assets and liabilities are the expected volatility in UAL common stock and the Company’s own credit risk. Significant increases (decreases) in expected stock volatility would result in a higher (lower) fair value measurement. Significant increases (decreases) in the Company’s own credit risk would result in a lower (higher) fair value measurement. A change in one of the inputs would not necessarily result in a directionally similar change in the other.
Fair value of the financial instruments included in the tables above was determined as follows:
Description		Fair Value Methodology
Cash and cash equivalents		The carrying amounts approximate fair value because of the short-term maturity of these assets.
Short-term investments and Restricted cash		Fair value is based on (a) the trading prices of the investment or similar instruments, (b) an income approach, which uses valuation techniques to convert future amounts into a single present amount based on current market expectations about those future amounts when observable trading prices are not available, (c) internally-developed models of the expected future cash flows related to the securities, or (d) broker quotes obtained by third-party valuation services.
Fuel derivatives		Derivative contracts are privately negotiated contracts and are not exchange traded. Fair value measurements are estimated with option pricing models that employ observable inputs. Inputs to the valuation models include contractual terms, market prices, yield curves, fuel price curves and measures of volatility, among others.
Foreign currency derivatives		Fair value is determined with a formula utilizing observable inputs. Significant inputs to the valuation models include contractual terms, risk-free interest rates and forward exchange rates.
Debt		Fair values were based on either market prices or the discounted amount of future cash flows using our current incremental rate of borrowing for similar liabilities.
Convertible debt derivative asset and option liability		United used a binomial lattice model to value the conversion options and the supplemental derivative assets. Significant binomial model inputs that are not objectively determinable include volatility and the Company’s credit risk component of the discount rate.

HEDGING_ACTIVITIES

HEDGING ACTIVITIES	9 Months Ended
	Sep. 30, 2013
HEDGING ACTIVITIES	NOTE 7—HEDGING ACTIVITIES
	Aircraft Fuel Hedges. To protect against increases in the prices of aircraft fuel, the Company routinely hedges a portion of its future fuel requirements. As of September 30, 2013, the Company had hedged approximately 45%, 23% and 1% of its projected fuel requirements (428 million, 901 million and 25 million gallons, respectively) for the remainder of 2013, 2014 and 2015, respectively, with commonly used financial hedge instruments based on aircraft fuel or closely related commodities, such as heating oil, diesel fuel and crude oil. As of September 30, 2013, the Company had fuel hedges expiring through March 2015. The Company does not enter into derivative instruments for non-risk management purposes.
	Upon proper qualification, the Company accounts for certain fuel derivative instruments as cash flow hedges. All derivatives designated as hedges that meet certain requirements are granted hedge accounting treatment. The types of instruments the Company utilizes that qualify for special hedge accounting treatment typically include swaps, call options, collars (which consist of a purchased call option and a sold put option) and four-way collars (a collar with a higher strike sold call option and a lower strike purchased put option). Generally, utilizing hedge accounting, all periodic changes in fair value of the derivatives designated as hedges that are considered to be effective are recorded in accumulated other comprehensive income (loss) (“AOCI”) until the underlying fuel is consumed and recorded in fuel expense. The Company is exposed to the risk that its hedges may not be effective in offsetting changes in the cost of fuel and that its hedges may not continue to qualify for hedge accounting. Hedge ineffectiveness results when the change in the fair value of the derivative instrument exceeds the change in the value of the Company’s expected future cash outlay to purchase and consume fuel. To the extent that the periodic changes in the fair value of the derivatives are not effective, that ineffectiveness is classified as Nonoperating income (expense): Miscellaneous, net in the statements of consolidated operations.
	The Company also utilizes certain derivative instruments that are economic hedges but do not qualify for hedge accounting under U.S. GAAP. As with derivatives that qualify for hedge accounting, the purpose of these economic hedges is to mitigate the adverse financial impact of potential increases in the price of fuel. Currently, the only such economic hedges in the Company’s hedging portfolio are three-way collars (which consist of a collar with a cap on maximum price protection available). The Company records changes in the fair value of three-way collars to Nonoperating income (expense): Miscellaneous, net in the statements of consolidated operations.
	If the Company terminates a derivative prior to its contractual settlement date, then the cumulative gain or loss recognized in AOCI at the termination date remains in AOCI until the forecasted transaction occurs. In a situation where it becomes probable that a hedged forecasted transaction will not occur, any gains and/or losses that have been recorded to AOCI would be required to be immediately reclassified into earnings. All cash flows associated with purchasing and settling derivatives are classified as operating cash flows in the condensed statements of consolidated cash flows.
	The Company records each derivative instrument as a derivative asset or liability (on a gross basis) in its consolidated balance sheets, and, accordingly, records any related collateral on a gross basis.
	The following tables present information about the financial statement classification of the Company’s derivatives (in millions):
	Classification	Balance Sheet Location		September 30, 2013				December 31, 2012
	Derivatives designated as cash flow hedges
	Assets:
	Fuel contracts due within one year	Receivables		$	23			$	7
	Liabilities:
	Fuel contracts due within one year	Current liabilities: Other		$	—			$	2
	Fuel contracts with maturities greater than one year	Other liabilities and deferred credits: Other			1				—
	Total liabilities			$	1			$	2
	Derivatives not designated for hedge accounting
	Assets:
	Fuel contracts due within one year	Receivables		$	29			$	44
	Fuel contracts with maturities greater than one year	Other assets: Other, net			2				—
	Total assets			$	31			$	44
	Liabilities:
	Fuel contracts due within one year	Current liabilities: Other		$	—			$	2
	Fuel contracts with maturities greater than one year	Other liabilities and deferred credits: Other			1				1
	Total liabilities			$	1			$	3
	Total derivatives
	Assets:
	Fuel contracts due within one year	Receivables		$	52			$	51
	Fuel contracts with maturities greater than one year	Other assets: Other, net			2				—
	Total assets			$	54			$	51
	Liabilities:
	Fuel contracts due within one year	Current liabilities: Other		$	—			$	4
	Fuel contracts with maturities greater than one year	Other liabilities and deferred credits: Other			2				1
	Total liabilities			$	2			$	5
	The following tables present the impact of derivative instruments and their location within the Company’s unaudited statements of consolidated operations (in millions):
	Derivatives designated as cash flow hedges
		Amount of  Gain								Gain (Loss) Reclassified from						Amount of Gain
		Recognized								AOCI into Fuel Expense						Recognized in Nonoperating
		in AOCI on Derivatives														income (expense):
		(Effective Portion)														Miscellaneous, net
																(Ineffective Portion)
		Three Months Ended								Three Months Ended						Three Months Ended
		September 30,								September 30,						September 30,
		2013				2012				2013			2012			2013		2012
	Fuel contracts	$	44			$	133			$	14		$	(38	)	$	1	$	2
	Derivatives designated as cash flow hedges
		Amount of Gain (Loss)								Loss Reclassified from						Amount of Loss
		Recognized								AOCI into Fuel Expense						Recognized in Nonoperating
		in AOCI on Derivatives														income (expense):
		(Effective Portion)														Miscellaneous, net
																(Ineffective Portion)
		Nine Months Ended								Nine Months Ended						Nine Months Ended
		September 30,								September 30,						September 30,
		2013				2012				2013			2012			2013		2012
	Fuel contracts	$	16			$	(36	)		$	(4	)	$	(107	)	$	—	$	(2	)
	Derivatives not designated for hedge accounting
	Fuel contracts
		Three Months Ended September 30,								Nine Months Ended September 30,
		2013				2012				2013			2012
	Amount of gain recognized in Nonoperating income (expense): Miscellaneous, net	$	61			$	10			$	30		$	10
	Derivative Credit Risk and Fair Value
	The Company is exposed to credit losses in the event of nonperformance by counterparties to its derivative instruments. While the Company records derivative instruments on a gross basis, the Company monitors its net derivative position with each counterparty to monitor credit risk. Based on the fair value of our fuel derivative instruments, our counterparties may require us to post collateral when the price of the underlying commodity decreases, and we may require our counterparties to provide us with collateral when the price of the underlying commodity increases. The following table presents information related to the Company’s derivative credit risk as of September 30, 2013 (in millions):
	Net derivative asset with counterparties	$	52
	Collateral held by the Company (classified as an other current liability)		—
	Potential loss related to the failure of the Company’s counterparties to perform		52

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	9 Months Ended
	Sep. 30, 2013
COMMITMENTS AND CONTINGENCIES	NOTE 8—COMMITMENTS AND CONTINGENCIES
	Commitments. As of September 30, 2013, United had firm commitments and options to purchase aircraft from The Boeing Company (“Boeing”), Embraer S.A. (“Embraer”) and Airbus S.A.S. (“Airbus”) presented in the table below:
	Aircraft Type		Number of  Firm
			Commitments (a)
	Airbus A350-1000			35
	Boeing 737-900ER			69
	Boeing 737 MAX 9			100
	Boeing 787-8/-9/-10			58
	Embraer EMB175			30
	(a)	United also has options and purchase rights for additional aircraft.
	The aircraft listed in the table above are scheduled for delivery from 2013 through 2025. In the remainder of 2013, United expects to take delivery of six Boeing 737-900ER aircraft and one Boeing 787-8 aircraft.
	On October 23, 2013, UAL and United entered into a purchase agreement assignment, pursuant to which UAL assigned its interest under the purchase agreement for the 100 Boeing 737 MAX 9 aircraft to United.
	The table below summarizes the capital commitments of UAL and United (including those assigned from UAL) as of September 30, 2013, which primarily relate to the acquisition of aircraft and related spare engines, aircraft improvements and acquisition of information technology services and assets:
	(In billions)
	Last three months of 2013		$	0.8
	2014			2.9
	2015			2.7
	2016			1.9
	2017			1.5
	After 2017			14.2
			$	24
	Any incremental firm aircraft orders, including through the exercise of purchase options and purchase rights, will increase the total future capital commitments of the Company.
	United has arranged for EETC financing of 18 Boeing 737-900ER aircraft, five of which are scheduled to be delivered during the remainder of 2013. United also has arranged for EETC financing of one Boeing 787-8 aircraft and a bank debt financing commitment for one Boeing 737-900ER aircraft scheduled for delivery in the fourth quarter of 2013. In addition, United has secured backstop financing commitments from certain of its aircraft manufacturers for a limited number of its future aircraft deliveries, subject to certain customary conditions. However, the Company does not have backstop financing or any financing currently in place for its other firm aircraft orders. Financing will be necessary to satisfy the Company’s capital commitments for its firm order aircraft and other related capital expenditures. The Company can provide no assurance that any financing not already in place for aircraft and spare engine deliveries will be available to the Company on acceptable terms when necessary or at all. See Note 9 of this report for additional information on aircraft financing.
	Capacity Purchase Agreements and Operating Leases
	In May 2013, United entered into a capacity purchase agreement with SkyWest Airlines, Inc. (“SkyWest”), a wholly-owned subsidiary of SkyWest, Inc., to operate 40 Embraer EMB175 aircraft under the United Express brand. SkyWest will purchase these 76-seat aircraft with deliveries in 2014 and 2015.
	In April 2013, United agreed to purchase 30 Embraer EMB175 aircraft. In August 2013, United entered into a capacity purchase agreement with Mesa Air Group, Inc. and Mesa Airlines, Inc. (“Mesa”), a wholly-owned subsidiary of Mesa Air Group, Inc., for Mesa to operate these 30 Embraer EMB175 aircraft under the United Express brand.
	The table below summarizes the Company’s future payments through the end of the terms of our capacity purchase commitments, excluding variable pass-through costs such as fuel and landing fees, among others. In addition, the table below summarizes the Company’s scheduled future minimum lease payments under aircraft operating leases having initial or remaining noncancelable lease terms of more than one year and includes aircraft rent under capacity purchase agreements, including estimated commitments from the Embraer EMB175 aircraft which will be delivered starting in 2014.
	(In millions)		Capacity		Aircraft
			Purchase		Operating
			Agreements		Leases
	Last three months of 2013		$	474	$	306
	2014			1,950		1,631
	2015			1,773		1,399
	2016			1,558		1,165
	2017			1,476		1,066
	After 2017			4,920		2,756
			$	12,151	$	8,323
	Facility and Other Operating Leases
	In April 2013, United signed a 20-year lease extension with the Port Authority of New York and New Jersey to continue its use of Terminal C1 and C2 at Newark Liberty International Airport (“Newark”). United also committed to invest an additional $150 million in facility upgrades at Newark to enhance the customer experience and efficiency of the operation.
	The table below summarizes the Company’s scheduled future minimum lease payments under facility operating leases having initial or remaining noncancelable lease terms of more than one year as of September 30, 2013.
	(In millions)		Facility and Other
			Operating Leases
	Last three months of 2013		$	297
	2014			1,038
	2015			900
	2016			829
	2017			782
	After 2017			6,814
			$	10,660
	Guarantees and Off-Balance Sheet Financing
	Guarantees. United is the guarantor of approximately $1.9 billion in aggregate principal amount of tax-exempt special facilities revenue bonds and interest thereon. These bonds, issued by various airport municipalities, are payable solely from rentals paid under long-term agreements with the respective governing bodies. The leasing arrangements associated with $1.6 billion of these obligations are accounted for as operating leases with the associated expense recorded on a straight-line basis resulting in ratable accrual of the lease obligation over the expected lease term. The leasing arrangements associated with $262 million of these obligations are accounted for as capital leases. All these bonds are due between 2015 and 2038.
	In the Company’s financing transactions that include loans, the Company typically agrees to reimburse lenders for any reduced returns with respect to the loans due to any change in capital requirements and, in the case of loans in which the interest rate is based on the London Interbank Offered Rate (“LIBOR”), for certain other increased costs that the lenders incur in carrying these loans as a result of any change in law, subject in most cases to obligations of the lenders to take certain limited steps to mitigate the requirement for, or the amount of, such increased costs. At September 30, 2013, the Company had $2.0 billion of floating rate debt and $296 million of fixed rate debt, with remaining terms of up to twelve years, that are subject to these increased cost provisions. In several financing transactions involving loans or leases from non-U.S. entities, with remaining terms of up to twelve years and an aggregate balance of $2.3 billion, the Company bears the risk of any change in tax laws that would subject loan or lease payments thereunder to non-U.S. entities to withholding taxes, subject to customary exclusions.
	Credit Facilities. On March 27, 2013, United and UAL entered into a new Credit and Guaranty Agreement (the “Credit Agreement”) as the borrower and guarantor, respectively, that provides United with a $1.0 billion revolving credit facility. As of September 30, 2013, United had its entire capacity of $1.0 billion available under the revolving credit facility. See Note 9 of this report for more information.
	Labor Negotiations. As of September 30, 2013, United had approximately 88,000 active employees, of whom approximately 80% were represented by various labor organizations. During third quarter 2013, the Company accepted an integrated seniority list for its pilots from the Air Line Pilots Association, International (“ALPA”). The Company also reached tentative agreements with respect to joint collective bargaining agreements with the International Association of Machinists (“IAM”) for the fleet service, passenger service and storekeeper work groups, subject to ratification by IAM members. The Company has offered an early out program for its fleet service, passenger service and storekeeper workgroups. The early out program accepted volunteers through October 18, 2013 and is subject to ratification of the tentative agreements with the IAM. The Company is not currently able to estimate the potential impact of the early out program. We are currently in the process of negotiating joint collective bargaining agreements with our technicians, flight attendants and dispatchers.

DEBT

DEBT	9 Months Ended
	Sep. 30, 2013
DEBT	NOTE 9—DEBT
	As of September 30, 2013, a substantial portion of our assets is pledged as collateral for our debt. These assets principally consist of aircraft, route authorities and loyalty program intangible assets. As of September 30, 2013, the Company was in compliance with its debt covenants.
	Unsecured 6.375% Senior Notes. In May 2013, UAL issued $300 million aggregate principal amount of 6.375% Senior Notes due June 1, 2018. The notes are fully and unconditionally guaranteed and recorded by United on its balance sheet as debt. The indenture for the 6.375% Senior Notes includes covenants that restrict the ability of UAL and its restricted subsidiaries (as defined in the indenture) to incur additional indebtedness, issue preferred stock, make investments, pay dividends or repurchase UAL’s common stock.
	6% Convertible Senior Notes. During the three and nine months ended September 30, 2013, UAL issued approximately 6 million and 28 million shares, respectively, of UAL common stock pursuant to agreements that UAL entered into with certain of its securityholders in exchange for approximately $51 million and $240 million, respectively, in aggregate principal amount of UAL’s outstanding 6% convertible senior notes due 2029 held by such securityholders. As of September 30, 2013, the outstanding balance is approximately $104 million.
	2013 Credit and Guaranty Agreement. On March 27, 2013, United and UAL entered into the Credit Agreement as the borrower and guarantor, respectively. The Credit Agreement consists of a $900 million term loan due April 1, 2019 and a $1.0 billion revolving credit facility available for drawing until April 1, 2018. As of September 30, 2013, United had its entire capacity of $1.0 billion available under the revolving credit facility. The obligations of United under the Credit Agreement are secured by liens on certain international route authorities between certain specified cities, certain take-off and landing rights and related assets of United.
	Borrowings under the Credit Agreement bear interest at a variable rate equal to LIBOR, subject to a 1% floor, plus a margin of 3.0% per annum, or another rate based on certain market interest rates, plus a margin of 2.0% per annum. The principal amount of the term loan must be repaid in consecutive quarterly installments of 0.25% of the original principal amount thereof, commencing on June 30, 2013, with any unpaid balance due on April 1, 2019. United may prepay all or a portion of the loan from time to time, at par plus accrued and unpaid interest. United pays a commitment fee equal to 0.75% per annum on the undrawn amount available under the revolving credit facility.
	The Credit Agreement includes covenants that, among other things, require the Company to maintain at least $3.0 billion of unrestricted liquidity and a minimum ratio of appraised value of collateral to the outstanding obligations under the Credit Agreement of 1.67 to 1.0, and restrict the Company’s ability to incur additional indebtedness, issue preferred stock, make investments, pay dividends or repurchase UAL’s common stock. The Credit Agreement contains events of default customary for this type of financing, including a cross default and cross acceleration provision to certain other material indebtedness of the Company.
	United Amended Credit Facility. On March 27, 2013, the Company used $900 million from the Credit Agreement, together with approximately $300 million of cash to retire the entire principal balance of a $1.2 billion term loan due 2014 that was outstanding under United’s Amended and Restated Revolving Credit, Term Loan and Guaranty Agreement, dated as of February 2, 2007 (the “Amended Credit Facility”). The Amended Credit Facility was terminated concurrently with the repayment of the term loan.
	$500 Million Revolving Credit Facility. On March 27, 2013, the Company terminated the $500 million revolving credit facility that it had previously entered into in December 2011. There were no outstanding borrowings under the revolving credit facility.
	Debt Redemptions. On February 1, 2013, United redeemed all of the $400 million aggregate principal amount of its 9.875% Senior Secured Notes due 2013 and $200 million aggregate principal amount of 12.0% Senior Second Lien Notes due 2013. On February 8, 2013, United redeemed all $123 million aggregate principal amount of the B tranche of the 2006-1 EETC equipment notes due 2013. On April 1, 2013, United redeemed all of the $180 million aggregate principal amount of the senior tranche of the 2006-1 EETC equipment notes due 2013.
	EETCs. In August 2013, December 2012 and October 2012, United created separate EETC pass-through trusts, each of which issued pass-through certificates. The proceeds of the issuance of the pass-through certificates are used to purchase equipment notes issued by United and secured by its aircraft. The Company records the debt obligation upon issuance of the equipment notes rather than upon the initial issuance of the pass-through certificates. The pass-through certificates represent fractional undivided interests in the respective pass-through trusts and are not obligations of United. The payment obligations under the equipment notes are those of United. Proceeds received from the sale of pass-through certificates are initially held by a depository in escrow for the benefit of the certificate holders until United issues equipment notes to the trust, which purchases such notes with a portion of the escrowed funds. These escrowed funds are not guaranteed by United and are not reported as debt on our consolidated balance sheet because the proceeds held by the depositary are not United’s assets. United received the remaining proceeds from the 2012 EETC pass-through trusts in the third quarter of 2013 and United expects to receive all proceeds from the 2013 EETC pass-through trusts by the end of 2014. Certain details of the pass-through trusts, which were issued in 2013 or for which we received proceeds in 2013, are as follows (in millions, except interest rate):
	EETC Date	Class		Principal				Final	Stated			Total debt		Proceeds		Remaining
								expected	interest			recorded		received  from		proceeds
								distribution	rate			as of September 30,		issuance of		from
								date				2013		debt in the nine		issuance of
														months ended		debt to be
														September 30,		received in
														2013		future
																periods
	Aug-13	A		$	720			August 2025		4.3	%	$	—	$	—	$	720
	Aug-13	B			209			Aug-21		5.375	%		—		—		209
	Dec-12	C			425			Apr-18		6.125	%		425		147		—
	Oct-12	A			712			October 2024		4	%		712		465		—
	Oct-12	B			132			Oct-20		5.5	%		132		86		—
				$	2,198							$	1,269	$	698	$	929
	The table below presents contractual principal payments at September 30, 2013 under then-outstanding long-term debt agreements in each of the next five calendar years (in millions):
		UAL				United
	Last three months of 2013	$	222			$	222
	2014		962				962
	2015		2,055				2,055
	2016		1,032				1,032
	2017		595				595
	After 2017		6,460				6,356
		$	11,326			$	11,222
	PBGC Notes. During the third quarter of 2013, UAL and United entered into a Second Supplemental Indenture (the “PBGC Second Supplemental Indenture”) to the Amended and Restated Indenture, dated as of January 11, 2013 (the “PBGC Indenture”), under which UAL’s 6% Notes due 2026, 6% Notes due 2028 and 8% Notes due 2024 are outstanding. Due to a request by the Pension Benefit Guaranty Corporation (the “PBGC”) pursuant to a contractual right of the PBGC, the PBGC Second Supplemental Indenture, among other things, amended and restated the covenants in the PBGC Indenture that restrict dividends and certain other payments by UAL and its restricted subsidiaries (as defined in the PBGC Indenture), restrict the incurrence of indebtedness by UAL and its restricted subsidiaries and provide for the designation of restricted and unrestricted subsidiaries of UAL so that these covenants would be substantially the same as the corresponding covenants in the indenture for the 6.375% Senior Notes due June 1, 2018.

SPECIAL_ITEMS

SPECIAL ITEMS	9 Months Ended
	Sep. 30, 2013
SPECIAL ITEMS	NOTE 10—SPECIAL ITEMS
	Special Charges. For the three and nine months ended September 30, special charges consisted of the following (in millions):
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2013		2012		2013		2012
	Labor agreement costs	$	127	$	454	$	127	$	454
	Merger integration-related costs		50		60		165		331
	Additional costs associated with the temporarily grounded Boeing 787 aircraft		—		—		18		—
	Voluntary severance and benefits		—		—		14		125
	(Gains) losses on sale of assets and other special items, net		34		—		31		(26	)
	Subtotal special charges		211		514		355		884
	Income tax benefit		—		—		—		(2	)
	Total special charges, net of income taxes	$	211	$	514	$	355	$	882
	Merger integration-related costs include compensation costs related to systems integration and training, branding activities, new uniforms, write-off or acceleration of depreciation on systems and facilities that are no longer used or planned to be used for significantly shorter periods, relocation for employees and severance primarily associated with administrative headcount reductions.
	On September 26, 2013, the Company announced that it had reached tentative agreements with respect to joint collective bargaining agreements with the IAM for the fleet service, passenger service and storekeeper workgroups, subject to ratification by IAM members. The Company recorded a $127 million special charge as a result. This expense is associated with lump sum cash payments that would be made in conjunction with the ratification of the agreements. The lump sum payments were accrued in third quarter 2013 as a result of the payments becoming probable, primarily due to reaching the tentative agreement, and are not in lieu of future pay increases and thus did not meet the deferral criteria under Accounting Standards Codification Topic 710. If ratified, the Company currently expects to make the related lump sum cash payments by early 2014.
	During the nine months ended September 30, 2013, the Company recorded $14 million associated with a voluntary program offered by United in which flight attendants took an unpaid 13-month leave of absence. The flight attendants continue to receive medical benefits and other company benefits while on leave under this program. Approximately 1,300 flight attendants opted to participate in the program. In addition, the Company recorded $18 million associated with the temporary grounding of its Boeing 787 aircraft. The charges are comprised of aircraft depreciation expense and dedicated personnel costs that the Company incurred while the aircraft were grounded. The aircraft returned to service in May 2013.
	During the three months ended September 30, 2013, the Company adjusted its reserves for certain legal matters by $34 million due to recent potential adverse developments. Additionally, during the nine months ended September 30, 2013, the Company recorded a $5 million gain related to a contract termination and $2 million in losses on the sale of assets.
	During the nine months ended September 30, 2012, the Company recorded $125 million of severance and benefits associated with three voluntary employee programs, respectively. During the first quarter of 2012, approximately 400 mechanics offered to retire early in exchange for a cash severance payment that was based on the number of years of service each employee had accumulated. The Company also offered a voluntary leave of absence program that approximately 1,800 flight attendants accepted, which allows for continued medical coverage during the leave of absence period. During the second quarter of 2012, as part of the recently amended collective bargaining agreement with the Association of Flight Attendants, the Company offered a voluntary program for flight attendants at United to retire early in exchange for a cash severance payment. The payments are dependent on the number of years of service each employee has accumulated. Approximately 1,300 flight attendants accepted this program and the Company estimated the amount for this voluntary program to be approximately $76 million.
	On August 3, 2012, the Company announced it had reached an agreement in principle with respect to a new joint collective bargaining agreement with ALPA representing pilots at United and Continental Airlines. The Company recorded $454 million of expense in third quarter 2012 associated with lump sum cash payments that would be made in conjunction with the ratification of the contract and the completion of the integrated pilot seniority list. This charge also included costs associated with changes to existing pilot disability plans negotiated in connection with the agreement in principle. The lump sum payments are not in lieu of future pay increases and were accrued in third quarter 2012 as a result of the payments becoming probable, primarily due to reaching the agreement in principle. The agreement was ratified in December 2012.
	In March 2013, the Company agreed to sell up to 30 Boeing 757-200 aircraft to FedEx Corporation beginning in April 2013. As of December 31, 2012, the Company operated 133 such aircraft. Given the planned sale of these 30 aircraft, the Company evaluated the entire fleet and determined that no impairment existed. In conjunction with that sale, the Company recorded accelerated depreciation of $31 million and $71 million on these aircraft during the three and nine months ended September 30, 2013, respectively, and this is classified as Operating expense: Depreciation and amortization in the statements of consolidated operations. The accelerated depreciation resulted from changes in the estimated useful lives and salvage values of the 30 aircraft as a result of the planned sale. These changes in estimate decreased net income by amounts disclosed above and reduced per share amounts by approximately $0.09 per UAL basic share ($0.08 per UAL diluted share) and $0.21 per UAL basic share ($0.18 per UAL diluted share) in the three and nine months ended September 30, 2013, respectively.
	Accruals
	The accrual for severance and medical costs was $29 million as of September 30, 2013, compared to $59 million as of September 30, 2012. In addition, the accrual balance of future lease payments on permanently grounded aircraft was $1 million as of September 30, 2013, compared to $6 million as of September 30, 2012.
	The severance-related accrual as of September 30, 2013 is expected to be paid through 2015. Lease payments for grounded aircraft are expected to continue through 2013.

ACCUMULATED_OTHER_COMPREHENSIV

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	9 Months Ended
	Sep. 30, 2013
ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	NOTE 11—ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)
	The tables below present the components of the Company’s AOCI, net of tax (in millions):
	UAL		Pension and			Unrealized			Other			Total
			Other			Gain (Loss)
			Postretirement			on
			Unrecognized			Derivatives
			Actuarial
			Gains (Losses)
			and Prior Service
			Cost
	Balance at June 30, 2013		$	(562	)	$	(20	)	$	13		$	(569	)
	Other comprehensive income (loss) before reclassifications			—			44			(5	)		39
	Actuarial gain due to curtailment and remeasurement			41			—			—			41
	Amounts reclassified from accumulated other comprehensive income			10			(14	)		—			(4	)
	Net current-period other comprehensive income (loss)			51			30			(5	)		76
	Balance at September 30, 2013		$	(511	)	$	10		$	8		$	(493	)
	Balance at December 31, 2012		$	(1,042	)	$	(10	)	$	6		$	(1,046	)
	Other comprehensive income before reclassifications			—			16			2			18
	Actuarial gain due to curtailment and remeasurement			483			—			—			483
	Amounts reclassified from accumulated other comprehensive income			48			4			—			52
	Net current-period other comprehensive income			531			20			2			553
	Balance at September 30, 2013		$	(511	)	$	10		$	8		$	(493	)
	UAL		Pension and			Unrealized			Other			Total
			Other			Gain (Loss)
			Postretirement			on
			Unrecognized			Derivatives
			Actuarial
			Gains (Losses)
			and Prior Service
			Cost
	Balance at June 30, 2012		$	(303	)	$	(199	)	$	3		$	(499	)
	Other comprehensive income before reclassifications			—			133			5			138
	Amounts reclassified from accumulated other comprehensive income			4			38			—			42
	Net current-period other comprehensive income			4			171			5			180
	Balance at September 30, 2012		$	(299	)	$	(28	)	$	8		$	(319	)
	Balance at December 31, 2011		$	(312	)	$	(99	)	$	(6	)	$	(417	)
	Other comprehensive income (loss) before reclassifications			—			(36	)		14			(22	)
	Amounts reclassified from accumulated other comprehensive income			13			107			—			120
	Net current-period other comprehensive income			13			71			14			98
	Balance at September 30, 2012		$	(299	)	$	(28	)	$	8		$	(319	)
	United		Pension and			Unrealized			Other			Income Tax			Total
			Other			Gain (Loss)						Benefit
			Postretirement			on						(Expense)
			Unrecognized			Derivatives
			Actuarial
			Gains (Losses)
			and Prior Service
			Cost
	Balance at June 30, 2013		$	(562	)	$	(20	)	$	13		$	—		$	(569	)
	Other comprehensive income (loss) before reclassifications			—			44			(5	)		—			39
	Actuarial gain due to curtailment and remeasurement			41			—			—			—			41
	Amounts reclassified from accumulated other comprehensive income			10			(14	)		—			—			(4	)
	Net current-period other comprehensive income (loss)			51			30			(5	)		—			76
	Balance at September 30, 2013		$	(511	)	$	10		$	8		$	—		$	(493	)
	Balance at December 31, 2012		$	(1,042	)	$	(10	)	$	5		$	(6	)	$	(1,053	)
	Other comprehensive income before reclassifications			—			16			3			—			19
	Actuarial gain due to curtailment and remeasurement			483			—			—			—			483
	Amounts reclassified from accumulated other comprehensive income			48			4			—			6			58
	Net current-period other comprehensive income			531			20			3			6			560
	Balance at September 30, 2013		$	(511	)	$	10		$	8		$	—		$	(493	)
	United		Pension and			Unrealized			Other			Income Tax			Total
			Other			Gain (Loss)						Expense
			Postretirement			on
			Unrecognized			Derivatives
Actuarial
Gains  (Losses)
and Prior Service
Cost
Balance at June 30, 2012		$	(303	)	$	(199	)	$	1		$	(6	)	$	(507	)
Other comprehensive income before reclassifications			—			133			6			—			139
Amounts reclassified from accumulated other comprehensive income			4			38			—			—			42
Net current-period other comprehensive income			4			171			6			—			181
Balance at September 30, 2012		$	(299	)	$	(28	)	$	7		$	(6	)	$	(326	)
Balance at December 31, 2011		$	(312	)	$	(99	)	$	(8	)	$	(6	)	$	(425	)
Other comprehensive income (loss) before reclassifications			—			(36	)		15			—			(21	)
Amounts reclassified from accumulated other comprehensive income			13			107			—			—			120
Net current-period other comprehensive income			13			71			15			—			99
Balance at September 30, 2012		$	(299	)	$	(28	)	$	7		$	(6	)	$	(326	)
UAL		Amount Reclassified from AOCI to Income												Affected Line Item in the
Details about AOCI Components														Statement Where Net Income is
														Presented
		Three Months  Ended						Nine Months Ended
		September 30,						September 30,
		2013			2012			2013			2012
Derivatives designated as cash flow hedges
Fuel contracts-reclassifications of (gains) losses into earnings (a)		$	(14	)	$	38		$	4		$	107		Aircraft fuel
Amortization of pension and post-retirement items
Amortization of unrecognized loss and prior service cost (a)		$	10		$	4	(b)	$	48		$	13	(b)	Salaries and related costs
(a)	Income tax expense offset by Company’s valuation allowance.
(b)	This accumulated other comprehensive income component is included in the computation of net periodic pension costs (see Note 5 of this report for additional details.)
United		Amount Reclassified from AOCI to Income												Affected Line Item in
Details about AOCI Components														the Statement Where
														Net Income is Presented
		Three Months  Ended						Nine Months Ended
		September 30,						September 30,
		2013			2012			2013			2012
Derivatives designated as cash flow hedges
Fuel contracts-reclassifications of (gains) losses into earnings (a)		$	(14	)	$	38		$	4		$	107		Aircraft fuel
Amortization of pension and post-retirement items
Amortization of unrecognized loss and prior service cost (a)		$	10		$	4	(b)	$	48		$	13	(b)	Salaries and related costs
Income tax expense on other comprehensive income		$	—		$	—		$	6		$	—		Income tax expense (benefit)
(a)	Income tax expense offset by Company’s valuation allowance.
(b)	This accumulated other comprehensive income component is included in the computation of net periodic pension costs (see Note 5 of this report for additional details.)

EARNINGS_LOSS_PER_SHARE_Tables

EARNINGS (LOSS) PER SHARE (Tables)	9 Months Ended
	Sep. 30, 2013
Computation of Earnings Per Share	The table below represents the computation of UAL’s basic and diluted earnings (loss) per share amounts and the number of securities that have been excluded from the computation of diluted earnings (loss) per share amounts because they were antidilutive (in millions, except per share amounts):
		Three Months Ended					Nine Months Ended
		September 30,					September 30,
		2013			2012		2013			2012
	Basic earnings (loss) per share:
	Net income (loss)	$	379		$	6	$	431		$	(103	)
	Less: Income allocable to participating securities		(1	)		—		(1	)		—
	Earnings (loss) available to common stockholders	$	378		$	6	$	430		$	(103	)
	Basic weighted average shares outstanding		357			331		343			331
	Earnings (loss) per share, basic	$	1.06		$	0.02	$	1.25		$	(0.31	)
	Diluted earnings (loss) per share:
	Earnings (loss) available to common stockholders	$	378		$	6	$	430		$	(103	)
	Effect of convertible notes		9			—		20			—
	Earnings (loss) available to common stockholders including the effect of dilutive securities	$	387		$	6	$	450		$	(103	)
	Diluted shares outstanding:
	Basic weighted-average shares outstanding		357			331		343			331
	Effect of convertible notes		37			—		46			—
	Effect of employee stock options		1			1		1			—
	Diluted weighted-average shares outstanding		395			332		390			331
	Earnings (loss) per share, diluted	$	0.98		$	0.02	$	1.15		$	(0.31	)
	Potentially dilutive shares excluded from diluted per share amounts:
	Restricted stock and stock options		3			5		3			6
	Convertible notes		—			61		4			61

EMPLOYEE_BENEFIT_PLANS_Tables

EMPLOYEE BENEFIT PLANS (Tables)	9 Months Ended
	Sep. 30, 2013
Components Of Net Periodic Benefit Cost	The Company’s net periodic benefit cost includes the following components (in millions):
			Pension Benefits						Other Postretirement Benefits
			Three Months Ended						Three Months Ended
			September 30,						September 30,
			2013			2012			2013			2012
	Service cost		$	29		$	25		$	14		$	11
	Interest cost			48			45			29			30
	Expected return on plan assets			(41	)		(33	)		(1	)		—
	Amortization of unrecognized loss and prior service			8			4			2			—
	cost
	Curtailment loss			—			—			—			—
	Settlement gain			(1	)		—			—			—
	Total		$	43		$	41		$	44		$	41
			Pension Benefits						Other Postretirement Benefits
			Nine Months Ended						Nine Months Ended
			September 30,						September 30,
			2013			2012			2013			2012
	Service cost		$	94		$	75		$	42		$	37
	Interest cost			142			137			85			93
	Expected return on plan assets			(121	)		(103	)		(2	)		(2	)
	Amortization of unrecognized (gain) loss and prior service			41			15			7			(2	)
	cost
	Curtailment loss			2			—			—			—
	Settlement gain			(2	)		—			—			—
	Total		$	156		$	124		$	132		$	126
Share-Based Compensation Expense	The table below presents information related to share-based compensation (in millions):
			Three Months Ended						Nine Months Ended
			September 30,						September 30,
			2013			2012			2013			2012
	Share-based compensation expense (a)		$	32		$	18		$	72		$	44
			September 30, 2013			December 31, 2012
	Unrecognized share-based compensation		$	55		$	33
	(a)	Includes $(2) million and $9 million of (benefit) expense recognized in merger integration-related costs for the three and nine months ended September 30, 2013, respectively. Includes $0 and $7 million of expense recognized in merger integration-related costs for the three and nine months ended September 30, 2012, respectively.

FINANCIAL_INSTRUMENTS_AND_FAIR1

FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (Tables)	9 Months Ended
	Sep. 30, 2013
Financial Assets and Liabilities Measured at Fair Value on Recurring Basis	The table below presents disclosures about the financial assets and financial liabilities measured at fair value on a recurring basis in the Company’s financial statements (in millions):
			September 30, 2013												December 31, 2012
			Total			Level 1			Level 2			Level 3			Total			Level 1			Level 2			Level 3
			UAL
	Cash and cash equivalents		$	3,935		$	3,935		$	—		$	—		$	4,770		$	4,770		$	—		$	—
	Short-term investments:
	Asset-backed securities			683			—			683			—			715			—			715			—
	Corporate debt			581			—			581			—			537			—			537			—
	Certificates of deposit placed through an account registry service (“CDARS”)			308			—			308			—			367			—			367			—
	Auction rate securities			104			—			—			104			116			—			—			116
	Other short-term investments			125			—			125			—			38			—			38			—
	Enhanced equipment trust certificates (“EETC”)			59			—			—			59			63			—			—			63
	Fuel derivative asset (liability), net			52			—			52			—			46			—			46			—
	Restricted cash			412			412			—			—			447			447			—			—
			United
	Cash and cash equivalents		$	3,928		$	3,928		$	—		$	—		$	4,765		$	4,765		$	—		$	—
	Short-term investments:
	Asset-backed securities			683			—			683			—			715			—			715			—
	Corporate debt			581			—			581			—			537			—			537			—
	CDARS			308			—			308			—			367			—			367			—
	Auction rate securities			104			—			—			104			116			—			—			116
	Other short-term investments			125			—			125			—			38			—			38			—
	EETC			59			—			—			59			63			—			—			63
	Fuel derivative asset (liability), net			52			—			52			—			46			—			46			—
	Restricted cash			411			411			—			—			447			447			—			—
	Convertible debt derivative asset			376			—			—			376			268			—			—			268
	Convertible debt option liability			(185	)		—			—			(185	)		(128	)		—			—			(128	)
Activity for "Level Three" Financial Assets and Financial Liabilities	The tables below present disclosures about the activity for “Level 3” financial assets and financial liabilities (in millions):
			Three Months Ended September 30,
			2013						2012
	UAL		Auction Rate			EETC			Auction Rate			EETC
			Securities						Securities
	Balance at June 30		$	115		$	62		$	112		$	63
	Settlements			(9	)		(2	)		—			(2	)
	Gains (losses):
	Reported in earnings—realized			1			—			—			—
	Reported in earnings—unrealized			—			—			1			—
	Reported in other comprehensive income (loss)			(3	)		(1	)		2			1
	Balance at September 30		$	104		$	59		$	115		$	62
			Nine Months Ended September 30,
			2013						2012
	UAL		Auction Rate			EETC			Auction Rate			EETC
			Securities						Securities
	Balance at January 1		$	116		$	63		$	113		$	60
	Settlements			(19	)		(4	)		—			(5	)
	Gains (losses):
	Reported in earnings—realized			3			—			—			—
	Reported in earnings—unrealized			1			—			—			7
	Reported in other comprehensive income (loss)			3			—			2			—
	Balance at September 30		$	104		$	59		$	115		$	62
			Three Months Ended September 30,
			2013												2012
	United		Auction			Convertible			Convertible			EETC			Auction			Convertible			Convertible			EETC
			Rate			Debt			Debt						Rate			Debt			Debt
			Securities			Supplemental			Conversion						Securities			Supplemental			Conversion
						Derivative			Option									Derivative			Option
						Asset			Liability									Asset			Liability
	Balance at June 30		$	115		$	395		$	(199	)	$	62		$	112		$	289		$	(147	)	$	63
	Settlements			(9	)		—			—			(2	)		—			—			—			(2	)
	Gains (losses):
	Reported in earnings:
	Realized			1			—			—			—			—			—			—			—
	Unrealized			—			(19	)		14			—			1			(87	)		56			—
	Reported in other comprehensive income (loss)			(3	)		—			—			(1	)		2			—			—			1
	Balance at September 30		$	104		$	376		$	(185	)	$	59		$	115		$	202		$	(91	)	$	62
			Nine Months Ended September 30,
			2013												2012
	United		Auction			Convertible			Convertible			EETC			Auction			Convertible			Convertible			EETC
			Rate			Debt			Debt						Rate			Debt			Debt
			Securities			Supplemental			Conversion						Securities			Supplemental			Conversion
						Derivative			Option									Derivative			Option
						Asset			Liability									Asset			Liability
	Balance at January 1		$	116		$	268		$	(128	)	$	63		$	113		$	193		$	(95	)	$	60
	Settlements			(19	)		—			—			(4	)		—			—			—			(5	)
	Gains (losses):
	Reported in earnings:
	Realized			3			—			—			—			—			—			—			—
	Unrealized			1			108			(57	)		—			—			9			4			7
	Reported in other comprehensive income (loss)			3			—			—			—			2			—			—			—
	Balance at September 30		$	104		$	376		$	(185	)	$	59		$	115		$	202		$	(91	)	$	62
Carrying Values and Estimated Fair Values of Financial Instruments	The table below presents the carrying values and estimated fair values of financial instruments not presented in the tables above (in millions):
	Fair Value of Debt by Fair Value Hierarchy Level
			September 30, 2013															December 31, 2012
			Carrying			Fair Value												Carrying			Fair Value
			Amount															Amount
						Total			Level 1			Level 2			Level 3						Total			Level 1			Level 2		Level 3
	UAL debt		$	11,161		$	12,036		$	—		$	7,428		$	4,608		$	12,252		$	13,419		$	—		$	8,045	$	5,374
	United debt			11,008			11,651			—			7,043			4,608			11,850			12,460			—			7,086		5,374
Quantitative Information about Level 3 Fair Value Measurements
	Quantitative Information About Level 3 Fair Value Measurements (in millions)
	Item		Fair Value at			Valuation		Unobservable Input	Range (Weighted
			September 30, 2013			Technique			Average)
	Auction rate securities		$	104		Valuation Service / Broker Quotes		Broker quotes (a)	NA
	EETC		$	59		Discounted Cash Flows		Structure credit risk (b)	5% - 6%(6%)
	Convertible debt derivative asset		$	376		Binomial Lattice Model		Expected volatility (c)	45% - 60%(47%)
								Own credit risk (d)	5% - 6%(5%)
	Convertible debt option liability		$	(185	)	Binomial Lattice Model		Expected volatility (c)	45% - 60%(47%)
								Own credit risk (d)	5% - 6%(5%)
	(a)	Broker quotes obtained by a third-party valuation service.
	(b)	Represents the credit risk premium of the EETC structure above the risk-free rate that the Company has determined market participants would use in pricing the instruments.
	(c)	Represents the range in volatility estimates that the Company has determined market participants would use when pricing the instruments.
	(d)	Represents the range of Company-specific risk adjustments that the Company has determined market participants would use as a model input.

HEDGING_ACTIVITIES_Tables

HEDGING ACTIVITIES (Tables)	9 Months Ended
	Sep. 30, 2013
Description of Derivative Instruments	The following tables present information about the financial statement classification of the Company’s derivatives (in millions):
	Classification	Balance Sheet Location		September 30, 2013				December 31, 2012
	Derivatives designated as cash flow hedges
	Assets:
	Fuel contracts due within one year	Receivables		$	23			$	7
	Liabilities:
	Fuel contracts due within one year	Current liabilities: Other		$	—			$	2
	Fuel contracts with maturities greater than one year	Other liabilities and deferred credits: Other			1				—
	Total liabilities			$	1			$	2
	Derivatives not designated for hedge accounting
	Assets:
	Fuel contracts due within one year	Receivables		$	29			$	44
	Fuel contracts with maturities greater than one year	Other assets: Other, net			2				—
	Total assets			$	31			$	44
	Liabilities:
	Fuel contracts due within one year	Current liabilities: Other		$	—			$	2
	Fuel contracts with maturities greater than one year	Other liabilities and deferred credits: Other			1				1
	Total liabilities			$	1			$	3
	Total derivatives
	Assets:
	Fuel contracts due within one year	Receivables		$	52			$	51
	Fuel contracts with maturities greater than one year	Other assets: Other, net			2				—
	Total assets			$	54			$	51
	Liabilities:
	Fuel contracts due within one year	Current liabilities: Other		$	—			$	4
	Fuel contracts with maturities greater than one year	Other liabilities and deferred credits: Other			2				1
	Total liabilities			$	2			$	5
Schedule of Gains (Losses) on Derivative Instruments	The following tables present the impact of derivative instruments and their location within the Company’s unaudited statements of consolidated operations (in millions):
	Derivatives designated as cash flow hedges
		Amount of  Gain								Gain (Loss) Reclassified from						Amount of Gain
		Recognized								AOCI into Fuel Expense						Recognized in Nonoperating
		in AOCI on Derivatives														income (expense):
		(Effective Portion)														Miscellaneous, net
																(Ineffective Portion)
		Three Months Ended								Three Months Ended						Three Months Ended
		September 30,								September 30,						September 30,
		2013				2012				2013			2012			2013		2012
	Fuel contracts	$	44			$	133			$	14		$	(38	)	$	1	$	2
	Derivatives designated as cash flow hedges
		Amount of Gain (Loss)								Loss Reclassified from						Amount of Loss
		Recognized								AOCI into Fuel Expense						Recognized in Nonoperating
		in AOCI on Derivatives														income (expense):
		(Effective Portion)														Miscellaneous, net
																(Ineffective Portion)
		Nine Months Ended								Nine Months Ended						Nine Months Ended
		September 30,								September 30,						September 30,
		2013				2012				2013			2012			2013		2012
	Fuel contracts	$	16			$	(36	)		$	(4	)	$	(107	)	$	—	$	(2	)
Schedule of Derivative Instruments not Designated as Hedges Gains (Losses)	Derivatives not designated for hedge accounting
	Fuel contracts
		Three Months Ended September 30,								Nine Months Ended September 30,
		2013				2012				2013			2012
	Amount of gain recognized in Nonoperating income (expense): Miscellaneous, net	$	61			$	10			$	30		$	10
Schedule of Derivative Credit Risk and Fair Value	The following table presents information related to the Company’s derivative credit risk as of September 30, 2013 (in millions):
	Net derivative asset with counterparties	$	52
	Collateral held by the Company (classified as an other current liability)		—
	Potential loss related to the failure of the Company’s counterparties to perform		52

COMMITMENTS_AND_CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES (Tables)	9 Months Ended
	Sep. 30, 2013
Firm Commitments and Options to Purchase Aircraft	The table below summarizes the capital commitments of UAL and United (including those assigned from UAL) as of September 30, 2013, which primarily relate to the acquisition of aircraft and related spare engines, aircraft improvements and acquisition of information technology services and assets:
	(In billions)
	Last three months of 2013		$	0.8
	2014			2.9
	2015			2.7
	2016			1.9
	2017			1.5
	After 2017			14.2
			$	24
Summary of Scheduled Future Minimum Lease Payments Under Aircraft Operating Leases and Capacity Purchase Agreements	The table below summarizes the Company’s future payments through the end of the terms of our capacity purchase commitments, excluding variable pass-through costs such as fuel and landing fees, among others. In addition, the table below summarizes the Company’s scheduled future minimum lease payments under aircraft operating leases having initial or remaining noncancelable lease terms of more than one year and includes aircraft rent under capacity purchase agreements, including estimated commitments from the Embraer EMB175 aircraft which will be delivered starting in 2014.
	(In millions)		Capacity		Aircraft
			Purchase		Operating
			Agreements		Leases
	Last three months of 2013		$	474	$	306
	2014			1,950		1,631
	2015			1,773		1,399
	2016			1,558		1,165
	2017			1,476		1,066
	After 2017			4,920		2,756
			$	12,151	$	8,323
Schedule of Future Minimum Rental Payments for Operating Leases	The table below summarizes the Company’s scheduled future minimum lease payments under facility operating leases having initial or remaining noncancelable lease terms of more than one year as of September 30, 2013.
	(In millions)		Facility and Other
			Operating Leases
	Last three months of 2013		$	297
	2014			1,038
	2015			900
	2016			829
	2017			782
	After 2017			6,814
			$	10,660
Aircraft
Firm Commitments and Options to Purchase Aircraft	As of September 30, 2013, United had firm commitments and options to purchase aircraft from The Boeing Company (“Boeing”), Embraer S.A. (“Embraer”) and Airbus S.A.S. (“Airbus”) presented in the table below:
	Aircraft Type		Number of  Firm
			Commitments (a)
	Airbus A350-1000			35
	Boeing 737-900ER			69
	Boeing 737 MAX 9			100
	Boeing 787-8/-9/-10			58
	Embraer EMB175			30
	(a)	United also has options and purchase rights for additional aircraft.

DEBT_Tables

DEBT (Tables)	9 Months Ended
	Sep. 30, 2013
Details of Pass Through Trusts	Certain details of the pass-through trusts, which were issued in 2013 or for which we received proceeds in 2013, are as follows (in millions, except interest rate):
	EETC Date	Class		Principal				Final	Stated			Total debt		Proceeds		Remaining
								expected	interest			recorded		received  from		proceeds
								distribution	rate			as of September 30,		issuance of		from
								date				2013		debt in the nine		issuance of
														months ended		debt to be
														September 30,		received in
														2013		future
																periods
	Aug-13	A		$	720			August 2025		4.3	%	$	—	$	—	$	720
	Aug-13	B			209			Aug-21		5.375	%		—		—		209
	Dec-12	C			425			Apr-18		6.125	%		425		147		—
	Oct-12	A			712			October 2024		4	%		712		465		—
	Oct-12	B			132			Oct-20		5.5	%		132		86		—
				$	2,198							$	1,269	$	698	$	929
Contractual Principal Payments	The table below presents contractual principal payments at September 30, 2013 under then-outstanding long-term debt agreements in each of the next five calendar years (in millions):
		UAL				United
	Last three months of 2013	$	222			$	222
	2014		962				962
	2015		2,055				2,055
	2016		1,032				1,032
	2017		595				595
	After 2017		6,460				6,356
		$	11,326			$	11,222

SPECIAL_ITEMS_Tables

SPECIAL ITEMS (Tables)	9 Months Ended
	Sep. 30, 2013
Components of Special Charges	For the three and nine months ended September 30, special charges consisted of the following (in millions):
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2013		2012		2013		2012
	Labor agreement costs	$	127	$	454	$	127	$	454
	Merger integration-related costs		50		60		165		331
	Additional costs associated with the temporarily grounded Boeing 787 aircraft		—		—		18		—
	Voluntary severance and benefits		—		—		14		125
	(Gains) losses on sale of assets and other special items, net		34		—		31		(26	)
	Subtotal special charges		211		514		355		884
	Income tax benefit		—		—		—		(2	)
	Total special charges, net of income taxes	$	211	$	514	$	355	$	882

ACCUMULATED_OTHER_COMPREHENSIV1

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Tables)	9 Months Ended
	Sep. 30, 2013
Components of Accumulated Other Comprehensive Income (loss), Net of Tax	The tables below present the components of the Company’s AOCI, net of tax (in millions):
	UAL		Pension and			Unrealized			Other			Total
			Other			Gain (Loss)
			Postretirement			on
			Unrecognized			Derivatives
			Actuarial
			Gains (Losses)
			and Prior Service
			Cost
	Balance at June 30, 2013		$	(562	)	$	(20	)	$	13		$	(569	)
	Other comprehensive income (loss) before reclassifications			—			44			(5	)		39
	Actuarial gain due to curtailment and remeasurement			41			—			—			41
	Amounts reclassified from accumulated other comprehensive income			10			(14	)		—			(4	)
	Net current-period other comprehensive income (loss)			51			30			(5	)		76
	Balance at September 30, 2013		$	(511	)	$	10		$	8		$	(493	)
	Balance at December 31, 2012		$	(1,042	)	$	(10	)	$	6		$	(1,046	)
	Other comprehensive income before reclassifications			—			16			2			18
	Actuarial gain due to curtailment and remeasurement			483			—			—			483
	Amounts reclassified from accumulated other comprehensive income			48			4			—			52
	Net current-period other comprehensive income			531			20			2			553
	Balance at September 30, 2013		$	(511	)	$	10		$	8		$	(493	)
	UAL		Pension and			Unrealized			Other			Total
			Other			Gain (Loss)
			Postretirement			on
			Unrecognized			Derivatives
			Actuarial
			Gains (Losses)
			and Prior Service
			Cost
	Balance at June 30, 2012		$	(303	)	$	(199	)	$	3		$	(499	)
	Other comprehensive income before reclassifications			—			133			5			138
	Amounts reclassified from accumulated other comprehensive income			4			38			—			42
	Net current-period other comprehensive income			4			171			5			180
	Balance at September 30, 2012		$	(299	)	$	(28	)	$	8		$	(319	)
	Balance at December 31, 2011		$	(312	)	$	(99	)	$	(6	)	$	(417	)
	Other comprehensive income (loss) before reclassifications			—			(36	)		14			(22	)
	Amounts reclassified from accumulated other comprehensive income			13			107			—			120
	Net current-period other comprehensive income			13			71			14			98
	Balance at September 30, 2012		$	(299	)	$	(28	)	$	8		$	(319	)
	United		Pension and			Unrealized			Other			Income Tax			Total
			Other			Gain (Loss)						Benefit
			Postretirement			on						(Expense)
			Unrecognized			Derivatives
			Actuarial
			Gains (Losses)
			and Prior Service
			Cost
	Balance at June 30, 2013		$	(562	)	$	(20	)	$	13		$	—		$	(569	)
	Other comprehensive income (loss) before reclassifications			—			44			(5	)		—			39
	Actuarial gain due to curtailment and remeasurement			41			—			—			—			41
	Amounts reclassified from accumulated other comprehensive income			10			(14	)		—			—			(4	)
	Net current-period other comprehensive income (loss)			51			30			(5	)		—			76
	Balance at September 30, 2013		$	(511	)	$	10		$	8		$	—		$	(493	)
	Balance at December 31, 2012		$	(1,042	)	$	(10	)	$	5		$	(6	)	$	(1,053	)
	Other comprehensive income before reclassifications			—			16			3			—			19
	Actuarial gain due to curtailment and remeasurement			483			—			—			—			483
	Amounts reclassified from accumulated other comprehensive income			48			4			—			6			58
	Net current-period other comprehensive income			531			20			3			6			560
	Balance at September 30, 2013		$	(511	)	$	10		$	8		$	—		$	(493	)
	United		Pension and			Unrealized			Other			Income Tax			Total
			Other			Gain (Loss)						Expense
			Postretirement			on
			Unrecognized			Derivatives
			Actuarial
Gains  (Losses)
and Prior Service
Cost
Balance at June 30, 2012		$	(303	)	$	(199	)	$	1		$	(6	)	$	(507	)
Other comprehensive income before reclassifications			—			133			6			—			139
Amounts reclassified from accumulated other comprehensive income			4			38			—			—			42
Net current-period other comprehensive income			4			171			6			—			181
Balance at September 30, 2012		$	(299	)	$	(28	)	$	7		$	(6	)	$	(326	)
Balance at December 31, 2011		$	(312	)	$	(99	)	$	(8	)	$	(6	)	$	(425	)
Other comprehensive income (loss) before reclassifications			—			(36	)		15			—			(21	)
Amounts reclassified from accumulated other comprehensive income			13			107			—			—			120
Net current-period other comprehensive income			13			71			15			—			99
Balance at September 30, 2012		$	(299	)	$	(28	)	$	7		$	(6	)	$	(326	)
UAL		Amount Reclassified from AOCI to Income												Affected Line Item in the
Details about AOCI Components														Statement Where Net Income is
														Presented
		Three Months  Ended						Nine Months Ended
		September 30,						September 30,
		2013			2012			2013			2012
Derivatives designated as cash flow hedges
Fuel contracts-reclassifications of (gains) losses into earnings (a)		$	(14	)	$	38		$	4		$	107		Aircraft fuel
Amortization of pension and post-retirement items
Amortization of unrecognized loss and prior service cost (a)		$	10		$	4	(b)	$	48		$	13	(b)	Salaries and related costs
(a)	Income tax expense offset by Company’s valuation allowance.
(b)	This accumulated other comprehensive income component is included in the computation of net periodic pension costs (see Note 5 of this report for additional details.)
United		Amount Reclassified from AOCI to Income												Affected Line Item in
Details about AOCI Components														the Statement Where
														Net Income is Presented
		Three Months  Ended						Nine Months Ended
		September 30,						September 30,
		2013			2012			2013			2012
Derivatives designated as cash flow hedges
Fuel contracts-reclassifications of (gains) losses into earnings (a)		$	(14	)	$	38		$	4		$	107		Aircraft fuel
Amortization of pension and post-retirement items
Amortization of unrecognized loss and prior service cost (a)		$	10		$	4	(b)	$	48		$	13	(b)	Salaries and related costs
Income tax expense on other comprehensive income		$	—		$	—		$	6		$	—		Income tax expense (benefit)
(a)	Income tax expense offset by Company’s valuation allowance.
(b)	This accumulated other comprehensive income component is included in the computation of net periodic pension costs (see Note 5 of this report for additional details.)

Computation_of_Earnings_Per_Sh

Computation of Earnings Per Share (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Basic earnings (loss) per share:
Net income (loss)	$379	$6	$431	($103)
Less: Income allocable to participating securities	-1		-1
Earnings (loss) available to common stockholders	378	6	430	-103
Basic weighted average shares outstanding	357	331	343	331
Earnings (loss) per share, basic	$1.06	$0.02	$1.25	($0.31)
Diluted earnings (loss) per share:
Earnings (loss) available to common stockholders	378	6	430	-103
Effect of convertible notes on diluted earnings per share, amount	9		20
Earnings (loss) available to common stockholders including the effect of dilutive securities	$387	$6	$450	($103)
Diluted shares outstanding:
Basic weighted-average shares outstanding	357	331	343	331
Effect of convertible notes on diluted earnings per share, shares	37		46
Effect of employee stock options	1	1	1
Diluted weighted-average shares outstanding	395	332	390	331
Earnings (loss) per share, diluted	$0.98	$0.02	$1.15	($0.31)
Restricted Stock And Stock Options
Potentially dilutive shares excluded from diluted per share amounts:
Potentially dilutive shares excluded from diluted per share amounts	3	5	3	6
Convertible Notes
Potentially dilutive shares excluded from diluted per share amounts:
Potentially dilutive shares excluded from diluted per share amounts		61	4	61

Earnings_loss_Per_Share_Additi

Earnings (loss) Per Share - Additional Information (Detail) (USD $)	3 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013
Computation Of Earnings Per Share Line Items
Common stock issued in exchange for convertible notes	6	28
Aggregate principal amount of senior convertible notes exchanged		$240
6% Convertible Senior Notes
Computation Of Earnings Per Share Line Items
Aggregate principal amount of senior convertible notes exchanged	51	$240
Debt instrument effective interest rate	6.00%	6.00%
Due date of debt instrument	2029	2029

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2013
Income Taxes [Line Items]
Federal statutory income tax rate	35.00%

Components_of_Net_Periodic_Ben

Components of Net Periodic Benefit Cost (Detail) (USD $)	3 Months Ended			9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Defined Benefit Plan Disclosure [Line Items]
Settlement gain	($1)
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	29		25	94	75
Interest cost	48		45	142	137
Expected return on plan assets	-41		-33	-121	-103
Amortization of unrecognized (gain) loss and prior service cost	8		4	41	15
Curtailment loss		2		2
Settlement gain	-1	-1		-2
Total	43		41	156	124
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	14		11	42	37
Interest cost	29		30	85	93
Expected return on plan assets	-1			-2	-2
Amortization of unrecognized (gain) loss and prior service cost	2			7	-2
Total	$44		$41	$132	$126

Employee_Benefit_Plans_Additio

Employee Benefit Plans - Additional Information (Detail) (USD $)

3 Months Ended

9 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

1 Months Ended

In Millions, unless otherwise specified

Sep. 30, 2013

Sep. 30, 2013

Jun. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Jun. 30, 2013

Sep. 30, 2013

Feb. 28, 2013

Feb. 28, 2013

Feb. 28, 2013

D

Pro Rata Share

Pro Rata Share

Pro Rata Share

Pension Benefits

Pension Benefits

Pension Benefits

Restricted Stock

Restricted Stock Units

Performance Shares

Pilots

Pilots

Pilots

Up to 6.9%

In excess of 6.9%

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Employer contribution to tax-qualified defined benefit pension plans

$122

$201

Defined benefit plan, curtailment loss

-2

-2

Defined benefit plan, settlement gain

1

1

1

2

Defined benefit plan, discount rate

5.13%

5.13%

4.59%

4.20%

Increase/ decrease in projected benefit obligation of the plans

522

Change in other comprehensive loss due to actuarial gain

41

483

Plan remeasurements decrease against the expected net periodic benefit cost

-13

-13

Number of days used to compute performance period average closing price of restricted stock units

20

Share-Based Compensation, award granted

0.5

0.5

1.3

Share-Based Compensation, vesting period

3 years

3 years

3 years

Share-Based Compensation, vesting date

31-Dec-15

Percentage of pre-tax earnings paid for profit sharing plan

15.00%

10.00%

20.00%

Share-based compensation program pre-tax profits excluding special items, profit sharing expense and share-based compensation program expense threshold

$10

Pre-tax margin

6.90%

ShareBased_Compensation_Expens

Share-Based Compensation Expense (Detail) (USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012		Dec. 31, 2012
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Share-based compensation expense	$32	[1]	$18	[1]	$72	[1]	$44	[1]
Unrecognized share-based compensation	$55				$55				$33
[1]	Includes $(2) million and $9 million of (benefit) expense recognized in merger integration-related costs for the three and nine months ended September 30, 2013, respectively. Includes $0 and $7 million of expense recognized in merger integration-related costs for the three and nine months ended September 30, 2012, respectively.

ShareBased_Compensation_Expens1

Share-Based Compensation Expense (Parenthetical) (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Expense (benefit) recognized in integration-related costs	($2)	$0	$9	$7

Financial_Assets_and_Liabiliti

Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (Fair Value, Measurements, Recurring, USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Cash and cash equivalents	$3,935	$4,770
Asset-backed Securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	683	715
Corporate Debt
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	581	537
CDARS
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	308	367
Auction Rate Securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	104	116
Other Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	125	38
EETC
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
EETC	59	63
Fuel Derivatives, Net
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fuel derivative asset (liability), net	52	46
Restricted Cash
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Restricted cash	412	447
Level 1 | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Cash and cash equivalents	3,935	4,770
Level 1 | Restricted Cash
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Restricted cash	412	447
Level 2 | Asset-backed Securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	683	715
Level 2 | Corporate Debt
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	581	537
Level 2 | CDARS
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	308	367
Level 2 | Other Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	125	38
Level 2 | Fuel Derivatives, Net
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fuel derivative asset (liability), net	52	46
Level 3 | Auction Rate Securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	104	116
Level 3 | EETC
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
EETC	59	63
United Airlines, Inc. | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Cash and cash equivalents	3,928	4,765
United Airlines, Inc. | Asset-backed Securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	683	715
United Airlines, Inc. | Corporate Debt
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	581	537
United Airlines, Inc. | CDARS
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	308	367
United Airlines, Inc. | Auction Rate Securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	104	116
United Airlines, Inc. | Other Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	125	38
United Airlines, Inc. | EETC
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
EETC	59	63
United Airlines, Inc. | Fuel Derivatives, Net
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fuel derivative asset (liability), net	52	46
United Airlines, Inc. | Restricted Cash
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Restricted cash	411	447
United Airlines, Inc. | Convertible Debt Derivative Asset
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Convertible debt derivative asset	376	268
United Airlines, Inc. | Convertible Debt Option Liability
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Convertible debt option liability	-185	-128
United Airlines, Inc. | Level 1 | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Cash and cash equivalents	3,928	4,765
United Airlines, Inc. | Level 1 | Restricted Cash
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Restricted cash	411	447
United Airlines, Inc. | Level 2 | Asset-backed Securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	683	715
United Airlines, Inc. | Level 2 | Corporate Debt
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	581	537
United Airlines, Inc. | Level 2 | CDARS
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	308	367
United Airlines, Inc. | Level 2 | Other Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	125	38
United Airlines, Inc. | Level 2 | Fuel Derivatives, Net
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fuel derivative asset (liability), net	52	46
United Airlines, Inc. | Level 3 | Auction Rate Securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Short-term investments	104	116
United Airlines, Inc. | Level 3 | EETC
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
EETC	59	63
United Airlines, Inc. | Level 3 | Convertible Debt Derivative Asset
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Convertible debt derivative asset	376	268
United Airlines, Inc. | Level 3 | Convertible Debt Option Liability
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Convertible debt option liability	($185)	($128)

Recovered_Sheet1

Financial Instruments and Fair Value Measurements - Additional Information (Detail) (USD $)

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

In Millions, unless otherwise specified

United Airlines, Inc.

United Airlines, Inc.

6% convertible junior subordinated debentures due 2030

Four Point Five Percent Convertible Notes Due Two Thousand Fifteen

EETC

EETC

Asset-backed Securities

Asset-backed Securities

Corporate Debt

Corporate Debt

Auction Rate Securities

Auction Rate Securities

Auction Rate Securities

Auction Rate Securities

Auction Rate Securities

United Airlines, Inc.

United Airlines, Inc.

United Airlines, Inc.

United Airlines, Inc.

United Airlines, Inc.

Minimum

Maximum

United Airlines, Inc.

United Airlines, Inc.

Minimum

Maximum

Minimum

Maximum

Minimum

Maximum

Fair Value [Line Items]

Available for sale investment, maturity date

2019

Available for sale investment, maturity year

1 year

42 years

1 year

22 years

1 year

33 years

Aggregate principal amount issued

$115

Available for sale investment, interest rates reset interval

28 days

7 days

35 days

Investment securities, unrealized gains (losses)

$2

Debt instrument convertible stated interest rate

8.00%

8.00%

8.00%

8.00%

6.00%

4.50%

Debt instrument maturity year

2030

2015

Activity_for_Level_Three_Finan

Activity for "Level Three" Financial Assets and Financial Liabilities (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Auction Rate Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	$115	$112	$116	$113
Settlements	-9		-19
Realized	1		3
Reported in earnings-unrealized		1	1
Reported in other comprehensive income (loss)	-3	2	3	2
Ending Balance	104	115	104	115
EETC
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	62	63	63	60
Settlements	-2	-2	-4	-5
Reported in earnings-unrealized				7
Reported in other comprehensive income (loss)	-1	1
Ending Balance	59	62	59	62
United Airlines, Inc. | Auction Rate Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	115	112	116	113
Settlements	-9		-19
Realized	1		3
Reported in earnings-unrealized		1	1
Reported in other comprehensive income (loss)	-3	2	3	2
Ending Balance	104	115	104	115
United Airlines, Inc. | EETC
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	62	63	63	60
Settlements	-2	-2	-4	-5
Reported in earnings-unrealized				7
Reported in other comprehensive income (loss)	-1	1
Ending Balance	59	62	59	62
United Airlines, Inc. | Convertible Debt Derivative Asset
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	395	289	268	193
Reported in earnings-unrealized	-19	-87	108	9
Ending Balance	376	202	376	202
United Airlines, Inc. | Convertible Debt Option Liability
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	-199	-147	-128	-95
Reported in earnings-unrealized	14	56	-57	4
Ending Balance	($185)	($91)	($185)	($91)

Carrying_Values_and_Estimated_

Carrying Values and Estimated Fair Values of Financial Instruments (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$11,326
United Airlines, Inc.
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	11,222
Carrying (Reported) Amount, Fair Value Disclosure
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	11,161	12,252
Carrying (Reported) Amount, Fair Value Disclosure | United Airlines, Inc.
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	11,008	11,850
Estimate of Fair Value, Fair Value Disclosure
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	12,036	13,419
Estimate of Fair Value, Fair Value Disclosure | United Airlines, Inc.
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	11,651	12,460
Estimate of Fair Value, Fair Value Disclosure | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	7,428	8,045
Estimate of Fair Value, Fair Value Disclosure | Level 2 | United Airlines, Inc.
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	7,043	7,086
Estimate of Fair Value, Fair Value Disclosure | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	4,608	5,374
Estimate of Fair Value, Fair Value Disclosure | Level 3 | United Airlines, Inc.
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$4,608	$5,374

Quantitative_Information_about

Quantitative Information about Level 3 Fair Value Measurements (Detail) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013
Auction Rate Securities
Fair Value Measurements [Line Items]
Level 3 Financial Instruments, asset	$104
Valuation Technique	Valuation Service / Broker Quotes
Unobservable Input	Broker quotes	[1]
EETC
Fair Value Measurements [Line Items]
Level 3 Financial Instruments, asset	59
Valuation Technique	Discounted Cash Flows
Unobservable Input	Structure credit risk	[2]
EETC | Structure Credit Risk
Fair Value Measurements [Line Items]
Level 3 fair value measurements, weighted average percentage	6.00%
Convertible Debt Derivative Asset
Fair Value Measurements [Line Items]
Level 3 Financial Instruments, asset	376
Valuation Technique	Binomial Lattice Model
Unobservable Input	Expected volatility Own credit risk	[3],[4]
Convertible Debt Derivative Asset | Expected Volatility
Fair Value Measurements [Line Items]
Level 3 fair value measurements, weighted average percentage	47.00%
Convertible Debt Derivative Asset | Own Credit Risk
Fair Value Measurements [Line Items]
Level 3 fair value measurements, weighted average percentage	5.00%
Convertible Debt Option Liability
Fair Value Measurements [Line Items]
Level 3 Financial Instruments, liability	($185)
Valuation Technique	Binomial Lattice Model
Unobservable Input	Expected volatility Own credit risk	[3],[4]
Convertible Debt Option Liability | Expected Volatility
Fair Value Measurements [Line Items]
Level 3 fair value measurements, weighted average percentage	47.00%
Convertible Debt Option Liability | Own Credit Risk
Fair Value Measurements [Line Items]
Level 3 fair value measurements, weighted average percentage	5.00%
Minimum | EETC | Structure Credit Risk
Fair Value Measurements [Line Items]
Level 3 fair value measurements, percentage	5.00%
Minimum | Convertible Debt Derivative Asset | Expected Volatility
Fair Value Measurements [Line Items]
Level 3 fair value measurements, percentage	45.00%
Minimum | Convertible Debt Derivative Asset | Own Credit Risk
Fair Value Measurements [Line Items]
Level 3 fair value measurements, percentage	5.00%
Minimum | Convertible Debt Option Liability | Expected Volatility
Fair Value Measurements [Line Items]
Level 3 fair value measurements, percentage	45.00%
Minimum | Convertible Debt Option Liability | Own Credit Risk
Fair Value Measurements [Line Items]
Level 3 fair value measurements, percentage	5.00%
Maximum | EETC | Structure Credit Risk
Fair Value Measurements [Line Items]
Level 3 fair value measurements, percentage	6.00%
Maximum | Convertible Debt Derivative Asset | Expected Volatility
Fair Value Measurements [Line Items]
Level 3 fair value measurements, percentage	60.00%
Maximum | Convertible Debt Derivative Asset | Own Credit Risk
Fair Value Measurements [Line Items]
Level 3 fair value measurements, percentage	6.00%
Maximum | Convertible Debt Option Liability | Expected Volatility
Fair Value Measurements [Line Items]
Level 3 fair value measurements, percentage	60.00%
Maximum | Convertible Debt Option Liability | Own Credit Risk
Fair Value Measurements [Line Items]
Level 3 fair value measurements, percentage	6.00%
[1]	Broker quotes obtained by a third-party valuation service.
[2]	Represents the credit risk premium of the EETC structure above the risk-free rate that the Company has determined market participants would use in pricing the instruments.
[3]	Represents the range in volatility estimates that the Company has determined market participants would use when pricing the instruments.
[4]	Represents the range of Company-specific risk adjustments that the Company has determined market participants would use as a model input.

Hedging_Activities_Additional_

Hedging Activities - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2013
Derivatives And Hedging Activities [Line Items]
Fuel hedges expiration date	2015-03
2013 Projected
Derivatives And Hedging Activities [Line Items]
Percentage of projected fuel requirements	45.00%
Volume of fuel hedging	428,000,000
2014 Projected
Derivatives And Hedging Activities [Line Items]
Percentage of projected fuel requirements	23.00%
Volume of fuel hedging	901,000,000
2015 Projected
Derivatives And Hedging Activities [Line Items]
Percentage of projected fuel requirements	1.00%
Volume of fuel hedging	25,000,000

Description_of_Derivative_Inst

Description of Derivative Instruments (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Derivatives, Fair Value [Line Items]
Fuel contracts, assets	$54	$51
Fuel contracts, liabilities	2	5
Receivables
Derivatives, Fair Value [Line Items]
Fuel contracts, assets	52	51
Other Liabilities Current
Derivatives, Fair Value [Line Items]
Fuel contracts, liabilities		4
Other Liabilities Noncurrent
Derivatives, Fair Value [Line Items]
Fuel contracts, liabilities	2	1
Other Assets
Derivatives, Fair Value [Line Items]
Fuel contracts, assets	2
Designated as Hedging Instrument | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Fuel contracts, liabilities	1	2
Designated as Hedging Instrument | Cash Flow Hedging | Receivables
Derivatives, Fair Value [Line Items]
Fuel contracts, assets	23	7
Designated as Hedging Instrument | Cash Flow Hedging | Other Liabilities Current
Derivatives, Fair Value [Line Items]
Fuel contracts, liabilities		2
Designated as Hedging Instrument | Cash Flow Hedging | Other Liabilities Noncurrent
Derivatives, Fair Value [Line Items]
Fuel contracts, liabilities	1
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Fuel contracts, assets	31	44
Fuel contracts, liabilities	1	3
Not Designated as Hedging Instrument | Receivables
Derivatives, Fair Value [Line Items]
Fuel contracts, assets	29	44
Not Designated as Hedging Instrument | Other Liabilities Current
Derivatives, Fair Value [Line Items]
Fuel contracts, liabilities		2
Not Designated as Hedging Instrument | Other Liabilities Noncurrent
Derivatives, Fair Value [Line Items]
Fuel contracts, liabilities	1	1
Not Designated as Hedging Instrument | Other Assets
Derivatives, Fair Value [Line Items]
Fuel contracts, assets	$2

Schedule_of_Gains_Losses_on_De

Schedule of Gains (Losses) on Derivative Instruments (Detail) (Designated as Hedging Instrument, Cash Flow Hedging, USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Designated as Hedging Instrument | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in AOCI on Derivatives (Effective Portion)	$44	$133	$16	($36)
Gain (Loss) Reclassified from AOCI into Income (Fuel Expense) (Effective Portion)	14	-38	-4	-107
Amount of Gain (Loss) Recognized in Income (Nonoperating Expense) (Ineffective Portion)	$1	$2		($2)

Schedule_of_Derivative_Instrum

Schedule of Derivative Instruments not Designated as Hedges Gains (Losses) (Detail) (Not Designated as Hedging Instrument, USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income (Nonoperating Expense)	$61	$10	$30	$10

Schedule_of_Derivative_Credit_

Schedule of Derivative Credit Risk and Fair Value (Detail) (USD $)	Sep. 30, 2013
In Millions, unless otherwise specified
Derivative [Line Items]
Net derivative asset with counterparties	$52
Collateral held by the Company (classified as an other current liability)
Potential loss related to the failure of the Company's counterparties to perform	$52

Firm_Commitments_and_Options_t

Firm Commitments and Options to Purchase Aircraft (Detail)	Apr. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013
	Embraer EMB175 aircraft	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.
	Aircraft	Capital Addition Purchase Commitments	Capital Addition Purchase Commitments	Capital Addition Purchase Commitments	Capital Addition Purchase Commitments	Capital Addition Purchase Commitments
		Airbus A350-1000 aircraft	Boeing 737	Boeing 737 MAX 9 Aircraft	Boeing 787-8/-9/-10	Embraer EMB175 aircraft
		Aircraft	Aircraft	Aircraft	Aircraft	Aircraft
Commitments [Line Items]
Number of new aircraft committed to purchase	30	35	69	100	58	30

Recovered_Sheet2

Commitments and Contingencies - Additional Information (Detail) (USD $)

1 Months Ended

9 Months Ended

12 Months Ended

1 Months Ended

Apr. 30, 2013

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2013

Apr. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Oct. 23, 2013

Sep. 30, 2013

Mar. 27, 2013

Sep. 30, 2013

Sep. 30, 2013

Apr. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Apr. 30, 2013

Sep. 30, 2013

Aircraft

United Airlines, Inc.

Tax-exempt special facilities revenue bonds

Embraer EMB175 aircraft

Floating Rate Debt

Fixed Rate Debt

Loans And Leases From Non U S Entities

Capital Addition Purchase Commitments

Capital Addition Purchase Commitments

Capital Addition Purchase Commitments

Capital Addition Purchase Commitments

Capital Addition Purchase Commitments

Capital Addition Purchase Commitments

Capital Addition Purchase Commitments

Capital Addition Purchase Commitments

Capital Addition Purchase Commitments

Revolving Credit Facility

Revolving Credit Facility

Maximum

Maximum

Maximum

Maximum

Maximum

Minimum

Minimum

Minimum

Employee

Aircraft

Boeing 737-900ER AirCraft

Boeing 737-900ER AirCraft

Boeing 787-8

Embraer EMB175 aircraft

Boeing 737 MAX 9 Aircraft

EETC

EETC

Notes Payable to Banks

Subsequent Event

Y

Tax-exempt special facilities revenue bonds

Embraer EMB175 aircraft

Loans And Leases From Non U S Entities

Capital Addition Purchase Commitments

Tax-exempt special facilities revenue bonds

Embraer EMB175 aircraft

Capital Addition Purchase Commitments

Aircraft

United Airlines, Inc.

United Airlines, Inc.

United Airlines, Inc.

United Airlines, Inc.

Boeing 737-900ER AirCraft

Boeing 787-8

Boeing 737-900ER AirCraft

Boeing 737 MAX 9 Aircraft

Y

United Airlines, Inc.

United Airlines, Inc.

Aircraft

Aircraft

Aircraft

Aircraft

Aircraft

Aircraft

Aircraft

United Airlines, Inc.

Aircraft

Commitments and Contingencies [Line Items]

New aircraft, scheduled delivery date

2015

2025

2014

2013

Number of aircraft expected to be delivered

6

1

Number of new aircraft committed to purchase

30

30

100

100

Number of aircraft under financing arrangement expected to be delivered

18

1

1

Number of aircraft under financing arrangement expected to be delivered during the reminder of 2013

5

Number of aircraft to be operated

133

30

Lease extension signed with the Port Authority of New York and New Jersey

20 years

Commitment to invest an additional amount in facility upgrades

$150,000,000

Guarantor obligations, maximum exposure

1,900,000,000

Operating leases obligations

1,600,000,000

Capital leases obligations

262,000,000

Debt instrument, maturity year

2038

2015

Debt instrument principal amount

2,000,000,000

296,000,000

2,300,000,000

Debt instrument, remaining terms (years)

12

12

Borrowing capacity under revolving credit facility

1,000,000,000

Capacity available under the revolving credit facility

$1,000,000,000

Number of employees

88,000

Percentage of employees represented by various U.S. labor organizations

80.00%

Schedule_of_Acquisition_of_Air

Schedule of Acquisition of Aircrafts and Related Spare Engines (Detail) (USD $)	Sep. 30, 2013
In Billions, unless otherwise specified
Commitments and Contingencies Disclosure [Line Items]
Last three months of 2013	$0.80
2014	2.9
2015	2.7
2016	1.9
2017	1.5
After 2017	14.2
Total commitments	$24

Summary_of_Scheduled_Future_Mi

Summary of Scheduled Future Minimum Lease Payments Under Aircraft Operating Leases (Detail) (USD $)	Sep. 30, 2013
In Millions, unless otherwise specified
Capacity Purchase Agreements
Commitments and Contingencies Disclosure [Line Items]
Last three months of 2013	$474
2014	1,950
2015	1,773
2016	1,558
2017	1,476
After 2017	4,920
Contractual Obligation, Total	12,151
Aircraft Operating Leases
Commitments and Contingencies Disclosure [Line Items]
Last three months of 2013	306
2014	1,631
2015	1,399
2016	1,165
2017	1,066
After 2017	2,756
Operating leases obligations	$8,323

Summary_of_Scheduled_Future_Mi1

Summary of Scheduled Future Minimum Lease Payments Under Facility Operating Leases (Detail) (Facility And Other Operating Leases, USD $)	Sep. 30, 2013
In Millions, unless otherwise specified
Facility And Other Operating Leases
Operating Leased Assets [Line Items]
Last three months of 2013	$297
2014	1,038
2015	900
2016	829
2017	782
After 2017	6,814
Operating leases obligations	$10,660

Debt_Additional_Information_De

Debt - Additional Information (Detail) (USD $)

3 Months Ended

6 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

6 Months Ended

1 Months Ended

1 Months Ended

Share data in Millions, unless otherwise specified

Sep. 30, 2013

Jun. 30, 2013

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2013

Feb. 01, 2013

Feb. 01, 2013

Feb. 08, 2013

Apr. 02, 2013

Jun. 30, 2013

Jun. 30, 2013

31-May-13

Mar. 27, 2013

Mar. 27, 2013

Sep. 30, 2013

Mar. 27, 2013

6% Convertible Senior Notes

6% Convertible Senior Notes

9.875% Senior Notes Due 2013

12% Second Lien Due 2013

Class B Pass Through Certificates

Senior tranche

LIBOR

Certain Market Interest Rates

Unsecured Debt

Term Loan Facility

Revolving Credit Facility

Revolving Credit Facility

Amended Credit Facility

Senior Notes 6 Point 375 Percent Due 2018

Debt Instrument [Line Items]

Aggregate principal amount

$400,000,000

$200,000,000

$123,000,000

$180,000,000

$300,000,000

$1,200,000,000

Debt instrument maturity date

1-Jun-18

1-Apr-19

1-Apr-18

Debt instrument stated interest rate

8.00%

8.00%

8.00%

9.88%

12.00%

6.38%

Debt instrument effective interest rate

6.00%

6.00%

Common stock issued in exchange for convertible notes

6

28

Aggregate principal amount of senior convertible notes exchanged

240,000,000

51,000,000

240,000,000

Debt instrument maturity year

2029

2029

2013

2013

2013

2013

2014

Outstanding balance of debt instrument

104,000,000

104,000,000

Credit Agreement

900,000,000

1,000,000,000

Available under revolving credit facility

1,000,000,000

Debt instrument, floor rate

1.00%

Debt instrument, basis spread on variable rate

3.00%

2.00%

Quarterly principal repayment amount

0.25%

Commencement date of installment payment

30-Jun-13

Debt instrument, maturity date

1-Apr-19

Commitment fee percentage

0.75%

Unrestricted liquidity requirement

3,000,000,000

Minimum ratio of appraised value of collateral to the outstanding obligations

1.67

1.67

Amount utilized to repay term loan

900,000,000

Cash utilized to repay term loan

300,000,000

Line of credit maximum borrowing capacity

$500,000,000

Details_of_Pass_Through_Trusts

Details of Pass Through Trusts (Detail) (USD $)	9 Months Ended			9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Feb. 08, 2013	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013
			Class B Pass Through Certificates	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.
						Class A Pass Through Certificates	Class A Pass Through Certificates	Class B Pass Through Certificates	Class B Pass Through Certificates	Class C Pass Through Certificates	EETC
						Aug-13	Oct-12	Aug-13	Oct-12	Dec-12
Debt Instrument [Line Items]
Principal			$123			$720	$712	$209	$132	$425	$2,198
Final expected distribution date						2025-08	2024-10	2021-08	2020-10	2018-04
Stated interest rate	8.00%	8.00%		8.00%	8.00%	4.30%	4.00%	5.38%	5.50%	6.13%
Total debt recorded							712		132	425	1,269
Proceeds received from issuance of debt	819	86		819	86		465		86	147	698
Remaining proceeds from issuance of debt to be received in future periods						$720		$209			$929

Contractual_Principal_Payments

Contractual Principal Payments Under then-Outstanding Long Term Debt (Detail) (USD $)	Sep. 30, 2013
In Millions, unless otherwise specified
Debt Instrument [Line Items]
Last three months of 2013	$222
2014	962
2015	2,055
2016	1,032
2017	595
After 2017	6,460
Long-term debt	11,326
United Airlines, Inc.
Debt Instrument [Line Items]
Last three months of 2013	222
2014	962
2015	2,055
2016	1,032
2017	595
After 2017	6,356
Long-term debt	$11,222

Components_of_Special_Charges_

Components of Special Charges (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Special Charges [Line Items]
Labor agreement costs	$127	$454	$127	$454
Merger integration-related costs	50	60	165	331
Additional costs associated with the temporarily grounded Boeing 787 aircraft			18
Voluntary severance and benefits			14	125
(Gains) losses on sale of assets and other special items, net	34		31	-26
Subtotal special charges	211	514	355	884
Income tax benefit				-2
Total special charges, net of income taxes	$211	$514	$355	$882

Special_Items_Additional_Infor

Special Items - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2013	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
	Aircraft				Attendant	Aircraft
Special Charges [Line Items]
Labor agreement costs		$127	$454	$127	$454
Severance and benefits				14	125
Number of flight attendants voluntarily on leave				1,300	1,800
Temporary grounding of 787 aircraft charges				18
Adjustment of reserves for certain legal matters		34
Gain related to contract termination				5
Loss on sale of asset				2
Number of mechanics offering to retire early					400
Number of flight attendants accepted voluntary retirement					1,300
Number of aircraft to be sold	30
Number of aircraft that the company operate						133
Accelerated depreciation recorded on aircraft		31		71
Decrease in net income per basic share		$0.09		$0.21
Decrease in net income per diluted share		$0.08		$0.18
Accrual severance and medical costs		29	59	29	59
Accrual balance of future lease		1	6	1	6
International Association Of Machinists
Special Charges [Line Items]
Labor agreement costs		127
Voluntary retirement program
Special Charges [Line Items]
Severance and benefits					$76

Components_of_Accumulated_Othe

Components of Accumulated Other Comprehensive Income (loss), Net of Tax (Detail) (USD $)	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011
					Accumulated Defined Benefit Plans Adjustment	Accumulated Defined Benefit Plans Adjustment	Accumulated Defined Benefit Plans Adjustment	Accumulated Defined Benefit Plans Adjustment	Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges	Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges	Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges	Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges	Other Accumulated Other Comprehensive Income	Other Accumulated Other Comprehensive Income	Other Accumulated Other Comprehensive Income	Other Accumulated Other Comprehensive Income	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.	United Airlines, Inc.
																					Accumulated Defined Benefit Plans Adjustment	Accumulated Defined Benefit Plans Adjustment	Accumulated Defined Benefit Plans Adjustment	Accumulated Defined Benefit Plans Adjustment	Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges	Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges	Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges	Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges	Other Accumulated Other Comprehensive Income	Other Accumulated Other Comprehensive Income	Other Accumulated Other Comprehensive Income	Other Accumulated Other Comprehensive Income	Income Tax Benefit Expense	Income Tax Benefit Expense	Income Tax Benefit Expense	Income Tax Benefit Expense
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	($569)	($499)	($1,046)	($417)	($562)	($303)	($1,042)	($312)	($20)	($199)	($10)	($99)	$13	$3	$6	($6)	($569)	($507)	($1,053)	($425)	($562)	($303)	($1,042)	($312)	($20)	($199)	($10)	($99)	$13	$1	$5	($8)	($6)	($6)	($6)	($6)
Other comprehensive income (loss) before reclassifications	39	138	18	-22					44	133	16	-36	-5	5	2	14	39	139	19	-21					44	133	16	-36	-5	6	3	15
Actuarial gain due to curtailment and remeasurement	41		483		41		483										41		483		41		483
Amounts reclassified from accumulated other comprehensive income	-4	42	52	120	10	4	48	13	-14	38	4	107					-4	42	58	120	10	4	48	13	-14	38	4	107					6
Net current-period other comprehensive income (loss)	76	180	553	98	51	4	531	13	30	171	20	71	-5	5	2	14	76	181	560	99	51	4	531	13	30	171	20	71	-5	6	3	15	6
Ending Balance	($493)	($319)	($493)	($319)	($511)	($299)	($511)	($299)	$10	($28)	$10	($28)	$8	$8	$8	$8	($493)	($326)	($493)	($326)	($511)	($299)	($511)	($299)	$10	($28)	$10	($28)	$8	$7	$8	$7		($6)	($6)	($6)

Details_about_Accumulated_Othe

Details about Accumulated Other Comprehensive Income Components (Detail) (USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Salaries And Related Costs
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of unrecognized loss and prior service cost	$10	[1]	$4	[1],[2]	$48	[1]	$13	[1],[2]
Fuel Oil Contract | Cash Flow Hedging | Aircraft Fuel
Accumulated Other Comprehensive Income (Loss) [Line Items]
Fuel contracts-reclassifications of (gains) losses into earnings	-14	[1]	38	[1]	4	[1]	107	[1]
United Airlines, Inc. | Salaries And Related Costs
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of unrecognized loss and prior service cost	10	[1]	4	[1],[2]	48	[1]	13	[1],[2]
United Airlines, Inc. | Income Tax Benefit Expense
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income tax expense on other comprehensive income					6
United Airlines, Inc. | Fuel Oil Contract | Cash Flow Hedging | Aircraft Fuel
Accumulated Other Comprehensive Income (Loss) [Line Items]
Fuel contracts-reclassifications of (gains) losses into earnings	($14)	[1]	$38	[1]	$4	[1]	$107	[1]
[1]	Income tax expense offset by Company's valuation allowance.
[2]	This accumulated other comprehensive income component is included in the computation of net periodic pension costs (see Note 5 of this report for additional details.)