Long Term Debt and Capital Leases (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2016
3.5% Senior Notes Due 2026
Debt Instrument [Line Items]
Long-term debt stated interest rate	3.50%
Senior notes due year	2026
4.375% Senior Notes Due 2022
Debt Instrument [Line Items]
Long-term debt stated interest rate	4.375%
Senior notes due year	2022