Long-Term Debt - Summary of Long-Term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Total long-term debt	$ 375,161	$ 363,870
Less current portion	(8,961)	(7,366)
Unamortized deferred issuance costs	(2,553)	(3,208)
Long-term debt, net of current portion	363,647	353,296
5.375% Notes, Due Oct. 2020 [Member]
Debt Instrument [Line Items]
Total long-term debt	250,000	250,000
Long-term debt, net of current portion	250,000	250,000
2.40% Term Loan, Due Jun. 2022 [Member]
Debt Instrument [Line Items]
Total long-term debt	8,282	10,109
2.05% Term Loan, Due Mar. 2023 [Member]
Debt Instrument [Line Items]
Total long-term debt	35,163	42,130
1.30% Term Loan, Due Jun. 2023 [Member]
Debt Instrument [Line Items]
Total long-term debt	9,788
1.55% Term Loan, Due Sep. 2025 [Member]
Debt Instrument [Line Items]
Total long-term debt	10,333	2,839
Revolving Credit Facility, Due Mar. 2020 [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 61,595	$ 58,792