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Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Line Items]
Federal net operating loss carryforwards net of valuation allowances	$ 18us-gaap_OperatingLossCarryforwards
Foreign net operating loss carryforwards	459
Accumulated and undistributed earnings of foreign subsidiaries	853
Reductions in unrecognized tax benefits from settlements	2	0	1
Internal Revenue Service (IRS)
Income Tax Disclosure [Line Items]
Federal net operating loss carryforwards net of valuation allowances	3,500
Internal Revenue Service (IRS) \| Maximum
Income Tax Disclosure [Line Items]
Operating loss carryforwards expiration period	Jan. 01, 2031
Pre-Separation taxes
Income Tax Disclosure [Line Items]
Reductions in unrecognized tax benefits from settlements	$ 128