Long-Term Debt - Summary of Long-Term Debt (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Total long-term debt	$ 415,438	$ 442,325
Less current portion	(1,821)
Long-term debt, net of current portion	413,617	442,325
Total long-term debt	415,438	442,325
5.375% Notes, Due Oct. 2020 [Member]
Debt Instrument [Line Items]
Total long-term debt	250,000	250,000
Total long-term debt	250,000	250,000
2.05% Term Loan, Due Mar. 2023 [Member]
Debt Instrument [Line Items]
Total long-term debt	58,285	58,785
Total long-term debt	58,285	58,785
Revolving Credit Facility, Due Nov. 2016 [Member]
Debt Instrument [Line Items]
Total long-term debt	107,153	133,540
Total long-term debt	$ 107,153	$ 133,540