Long-Term Debt - Long-Term Debt Instrument (Additional Information) (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
4.500% senior notes, Series E, quarterly interest payments, balloon due 2018
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	4.50%	4.50%
Debt instrument maturity year	2018	2018
4.200% senior notes, semi-annual interest payments, net of the unamortized discount, balloon due 2024
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	4.20%	4.20%
Debt instrument maturity year	2024	2024
5-year term-loan facility, periodic interest and principal payments, LIBOR plus up to 1.750%, expires May 20, 2019
Debt Instrument [Line Items]
Line of credit facility, expiration period	5 years	5 years
Line of credit facility, expiration date	May 20, 2019	May 20, 2019
5-year term-loan facility, periodic interest and principal payments, LIBOR plus up to 1.750%, expires May 20, 2019 | LIBOR
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.75%	1.75%
Five Year Term Loan Facility Expires In Two Thousand Ninteen Current [Member]
Debt Instrument [Line Items]
Debt instrument maturity year	2019	2019
5-year revolving-loan facility, periodic interest payments, LIBOR plus up to 1.500%, plus commitment fees up to 0.250%, expires May 20, 2019
Debt Instrument [Line Items]
Line of credit facility, expiration period	5 years	5 years
Line of credit facility, commitment fee percentage	0.25%	0.25%
Line of credit facility, expiration date	May 20, 2019	May 20, 2019
5-year revolving-loan facility, periodic interest payments, LIBOR plus up to 1.500%, plus commitment fees up to 0.250%, expires May 20, 2019 | LIBOR
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.50%	1.50%
Wells Fargo [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	$ 800,000	$ 800,000