Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Income Tax [Line Items]
Effective Income Tax rate Reconciliation, Percent	19.20%	21.90%
Deferred tax expense overstated amount			$ 18
Tools [Member]
Income Tax [Line Items]
Deferred Tax Liabilities, Tax Deferred Income			$ 164