Statements of Consolidated Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash Flows from Operating Activities:
Net income	$ 2,263	$ 7,340	$ 1,132
Adjustments to reconcile net income to net cash provided by operating activities -
Deferred income taxes	1,648	(3,177)	13
Depreciation and amortization	1,977	1,819	1,679
Special charges, non-cash portion	391	247	78
Other operating activities	109	115	(21)
Changes in operating assets and liabilities -
(Increase) decrease in fuel hedge collateral	26	551	(577)
(Decrease) increase in fuel derivatives	(20)	(305)	436
Decrease in other liabilities	(114)	(198)	(238)
Decrease in frequent flyer deferred revenue and advanced purchase of miles	(641)	(200)	(88)
Increase in other assets	(298)	(160)	(34)
Increase (decrease) in accounts payable	239	(77)	(251)
Increase (decrease) in advance ticket sales	(22)	52	296
(Increase) decrease in receivables	(16)	(15)	209
Net cash provided by operating activities	5,542	5,992	2,634
Cash Flows from Investing Activities:
Capital expenditures	(3,223)	(2,747)	(2,005)
Purchases of short-term and other investments	(2,768)	(2,517)	(3,569)
Proceeds from sale of short-term and other investments	2,712	2,707	3,112
Proceeds from sale of property and equipment	28	86	94
Other, net	13	(136)	37
Net cash used in investing activities	(3,238)	(2,607)	(2,331)
Cash Flows from Financing Activities:
Repurchases of common stock	(2,614)	(1,233)	(312)
Payments of long-term debt	(1,215)	(2,178)	(2,503)
Proceeds from issuance of long-term debt	808	1,073	1,432
Principal payments under capital leases	(136)	(123)	(127)
Capitalized financing costs	(64)	(37)	(104)
Proceeds from the exercise of stock options	6	16	60
Other, net	2	(13)	(42)
Net cash used in financing activities	(3,213)	(2,495)	(1,596)
Net increase (decrease) in cash, cash equivalents and restricted cash	(909)	890	(1,293)
Cash, cash equivalents and restricted cash at beginning of year	3,212	2,322	3,615
Cash, cash equivalents and restricted cash at end of year	2,303	3,212	2,322
Investing and Financing Activities Not Affecting Cash:
Property and equipment acquired through the issuance of debt	386	866	1,114
Airport construction financing	91	17	14
Operating lease conversions to capital lease	12	285
Exchange of convertible notes for common stock		202	260
Cash Paid (Refunded) During the Period for:
Interest	584	660	748
Income taxes	14	15	(16)
United Airlines, Inc.
Cash Flows from Operating Activities:
Net income	2,264	7,301	1,114
Adjustments to reconcile net income to net cash provided by operating activities -
Deferred income taxes	1,650	(3,136)	13
Depreciation and amortization	1,977	1,819	1,679
Special charges, non-cash portion	391	247	78
Other operating activities	108	115	4
Changes in operating assets and liabilities -
(Increase) decrease in fuel hedge collateral	26	551	(577)
(Decrease) increase in fuel derivatives	(20)	(305)	436
Decrease in other liabilities	(112)	(199)	(236)
Decrease in frequent flyer deferred revenue and advanced purchase of miles	(641)	(200)	(88)
Increase in other assets	(251)	(160)	(34)
Increase (decrease) in accounts payable	239	(77)	(251)
Increase (decrease) in advance ticket sales	(22)	52	296
(Increase) decrease in receivables	(16)	(15)	209
Increase in intercompany receivables	(58)	(12)
Decrease in intercompany payables			(118)
Net cash provided by operating activities	5,535	5,981	2,525
Cash Flows from Investing Activities:
Capital expenditures	(3,223)	(2,747)	(2,005)
Purchases of short-term and other investments	(2,768)	(2,517)	(3,569)
Proceeds from sale of short-term and other investments	2,712	2,707	3,112
Proceeds from sale of property and equipment	28	86	94
Other, net	13	(136)	37
Net cash used in investing activities	(3,238)	(2,607)	(2,331)
Cash Flows from Financing Activities:
Dividend to UAL	(2,614)	(1,233)	(212)
Payments of long-term debt	(1,215)	(2,178)	(2,503)
Proceeds from issuance of long-term debt	808	1,073	1,432
Principal payments under capital leases	(136)	(123)	(127)
Capitalized financing costs	(64)	(37)	(104)
Proceeds from the exercise of stock options	6	16	60
Other, net	9	(2)	(33)
Net cash used in financing activities	(3,206)	(2,484)	(1,487)
Net increase (decrease) in cash, cash equivalents and restricted cash	(909)	890	(1,293)
Cash, cash equivalents and restricted cash at beginning of year	3,206	2,316	3,609
Cash, cash equivalents and restricted cash at end of year	2,297	3,206	2,316
Investing and Financing Activities Not Affecting Cash:
Property and equipment acquired through the issuance of debt	386	866	1,114
Airport construction financing	91	17	14
Operating lease conversions to capital lease	12	285
Transfer of UAL subsidiaries to United			186
Exchange of convertible notes for common stock			156
Cash Paid (Refunded) During the Period for:
Interest	584	660	748
Income taxes	$ 14	$ 15	$ (16)