Annual Future Minimum Payments under Capital Leases and Noncancelable Operating Leases (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
2013	$ 89
2014	85
2015	81
2016	74
2017	66
Thereafter	374
Total minimum lease payments	769
2013	7
2014	7
2015	6
2016	3
Thereafter	1
Total minimum lease payments	24
Amounts representing interest	3
Present value of net minimum lease payments	$ 21

Amount of minimum lease payments for capital leases.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 16

-Subparagraph a(ii)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.