Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of impact of recently adopted accounting standards

We recast certain prior period amounts to conform with the adoption of the revenue recognition and retirement benefits standards, as shown in the tables below.

	Three Months Ended September 30, 2017									Nine Months Ended September 30, 2017
(in millions, except per share data)	As Previously Reported			Adjustments			Current Presentation			As Previously Reported			Adjustments			Current Presentation
Income statement:
Passenger revenue	$	9,399		$	580		$	9,979		$	26,318		$	1,607		$	27,925
Cargo revenue	187			4			191			530			12			542
Other revenue	1,474			(583		)	891			4,151			(1,708		)	2,443
Total operating revenue	11,060			1			11,061			30,999			(89		)	30,910
Operating expense	9,221			17			9,238			26,079			26			26,105
Non-operating expense	(34		)	(13		)	(47		)	(309		)	(39		)	(348		)
Income tax provision	(627		)	10			(617		)	(1,606		)	56			(1,550		)
Net income	1,178			(19		)	1,159			3,005			(98		)	2,907
Diluted earnings per share	$	1.64		$	(0.03	)	$	1.61		$	4.13		$	(0.13	)	$	4.00

	December 31, 2017
(in millions)	As Previously Reported		Adjustments			Current Presentation
Balance sheet:
Deferred income taxes, net	$	935	$	419		$	1,354
Air traffic liability	4,888		(524		)	4,364
Frequent flyer deferred revenue (current and noncurrent)	4,118		2,203			6,321
Other accrued and other noncurrent liabilities	3,969		120			4,089
Retained earnings	9,636		(1,380		)	8,256