Fair Value Measurement (Additional Information) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	$ 3,346	$ 3,939
Long-term debt (excluding capital lease obligations), fair values	3,683	4,484
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets carrying amount	$ 0	$ 0	$ 0