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Long-Term Debt - Summary of Long-Term Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total long-term debt	$ 296,755	$ 315,419
Less current portion	(23,942)	(25,057)
Unamortized deferred issuance costs	(1,734)	(1,898)
Long-term debt, net of current portion	271,079	288,464
Revolving Credit Facility, Due Feb. 2024 [Member]
Debt Instrument [Line Items]
Total long-term debt	36,531	36,813
2.40% Term Loan, Due Jun. 2022 [Member]
Debt Instrument [Line Items]
Total long-term debt	2,094	2,629
Term Loan, Due Feb. 2024 [Member]
Debt Instrument [Line Items]
Total long-term debt	235,379	249,715
2.05% Term Loan, Due Mar. 2023 [Member]
Debt Instrument [Line Items]
Total long-term debt	12,516	14,737
1.30% Term Loan, Due Jun. 2023 [Member]
Debt Instrument [Line Items]
Total long-term debt	3,769	4,382
1.55% Term Loan, Due Sep. 2025 [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 6,466	$ 7,143

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