CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net Income	$ 149us-gaap_NetIncomeLoss	$ 94us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	76	70
Stock-based compensation and other	9us-gaap_ShareBasedCompensation	4us-gaap_ShareBasedCompensation
Changes in certain assets and liabilities:
Changes in deferred income taxes	(6)	9
Increase in air traffic liability	183	185
Increase (decrease) in deferred revenue	8	(1)
Other - net	95	(119)
Net cash provided by operating activities	514	242
Property and equipment additions:
Aircraft and aircraft purchase deposits	(245)us-gaap_PaymentsForFlightEquipment	(65)us-gaap_PaymentsForFlightEquipment
Other flight equipment	(21)	(17)
Other property and equipment	(13)	(11)
Total property and equipment additions	(279)	(93)
Purchases of marketable securities	(403)	(305)
Sales and maturities of marketable securities	259	227
Proceeds from disposition of assets and changes in restricted deposits	2	7
Net cash used in investing activities	(421)	(164)
Cash flows from financing activities:
Long-term debt payments	(35)us-gaap_RepaymentsOfLongTermDebt	(37)us-gaap_RepaymentsOfLongTermDebt
Common stock repurchases	(102)	(30)
Dividends paid	(26)us-gaap_PaymentsOfDividends	(17)us-gaap_PaymentsOfDividends
Other financing activities	14	16
Net cash used in financing activities	(149)	(68)
Net increase (decrease) in cash and cash equivalents	(56)	10
Cash and cash equivalents at beginning of year	107	80
Cash and cash equivalents at end of the period	51	90
Cash paid during the period for:
Interest (net of amount capitalized)	7us-gaap_InterestPaidNet	11us-gaap_InterestPaidNet
Income taxes paid (received)	$ (65)us-gaap_IncomeTaxesPaidNet	$ 6us-gaap_IncomeTaxesPaidNet

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Other cash or noncash adjustments to reconcile net income to cash provided by (used in) operating activities that are not separately disclosed in the statement of cash flows (for example, cash received or cash paid during the current period for miscellaneous operating activities, net change during the reporting period in other assets or other liabilities).

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