Impairments - Fair Value Measurements Table (Detail) (Fair Value, Inputs, Level 3 [Member], Income Approach Valuation Technique [Member], Nonrecurring [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Fair Value, Inputs, Level 3 [Member] | Income Approach Valuation Technique [Member] | Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets held for use	$ 731		$ 548
Cost-method investment (1)	$ 32	[1]	$ 32	[1]

[1] This represents the Company’s after-tax net investment.