Future Minimum Annual Rental Commitments Required Under Non-Cancelable Leases (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Schedule of Operating Leases [Line Items]
2012	$ 1
2013	1
2014
2015
2016
Thereafter
Total minimum lease payments	2
2012	113
2013	45
2014	43
2015	41
2016	39
Thereafter	1,379
Total minimum lease payments	$ 1,660

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The total of contractually required rental payments on leases meeting the criteria for capitalization.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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