Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 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 June 30, 2017									Six Months Ended June 30, 2017
(in millions, except per share data)	As Previously Reported			Adjustments			Current Presentation			As Previously Reported			Adjustments			Current Presentation
Income statement:
Passenger revenue	$	9,231		$	537		$	9,768		$	16,919		$	1,027		$	17,946
Cargo revenue	183			4			187			343			7			350
Other revenue	1,377			(585		)	792			2,677			(1,125		)	1,552
Total operating revenue	10,791			(44		)	10,747			19,939			(91		)	19,848
Operating expense	8,763			2			8,765			16,858			9			16,867
Non-operating expense	(137		)	(14		)	(151		)	(275		)	(26		)	(301		)
Income tax provision	(667		)	22			(645		)	(979		)	46			(933		)
Net income	1,224			(38		)	1,186			1,827			(80		)	1,747
Diluted earnings per share	$	1.68		$	(0.06	)	$	1.62		$	2.50		$	(0.11	)	$	2.39

	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