Restructuring and Other Items (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 Facilities and Fleet [Member]	Jun. 30, 2012 Facilities and Fleet [Member]	Jun. 30, 2013 Facilities and Fleet [Member]	Jun. 30, 2012 Facilities and Fleet [Member]	Mar. 31, 2012 Gain on slot exchange and divestiture [Member]	Dec. 31, 2011 Gain on slot exchange and divestiture [Member]
Restructuring Cost and Reserve [Line Items]
Deferred Gain on Sale of Property										$ 78
Restructuring and other items	$ 34	$ 193	$ 136	$ 181	$ 34	$ 22	$ 136	$ 49	$ (39)

The aggregate amount provided for estimated restructuring charges, remediation costs, and asset impairment loss during an accounting period. Generally, these items are either unusual or infrequent, but not both (in which case they would be extraordinary items).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.3)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration