Oil Refinery (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Segment Reporting Information [Line Items]
Operating Revenue	$ 8,916	$ 8,500
Operating Income (Loss)	620	222
Interest Expense, Net	165	178
Depreciation and amortization	442	405
Total assets, end of period	52,167	45,068	52,252
Capital Expenditures	614	647
Airline [Member]
Segment Reporting Information [Line Items]
Operating Revenue	8,916	8,500
Operating Income (Loss)	661	244
Interest Expense, Net	165	178
Depreciation and amortization	437	401
Total assets, end of period	51,016	43,789
Capital Expenditures	592	641
Refinery [Member]
Segment Reporting Information [Line Items]
Operating Revenue	1,463	1,731
Operating Income (Loss)	(41)	(22)
Interest Expense, Net	0	0
Depreciation and amortization	5	4
Total assets, end of period	1,151	1,279
Capital Expenditures	22	6
Sales to airline segment [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating Revenue	(249)	(292)
Exchanged products [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating Revenue	(1,003)	(1,321)
Sales of refined products to third parties [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating Revenue	$ (211)	$ (118)