Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Jul. 01, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Value	$ 456,214	$ 315,419
Fair Value	456,363	315,646
Interest rate on debt			1.25%
Variable rate debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Value	200,527	36,813
Fair Value	200,527	36,813
Term loan, due Feb. 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Value	226,080	249,715
Fair Value	226,080	249,715
2.40% Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Value	1,241	2,629
Fair Value	$ 1,250	$ 2,651
Interest rate on debt	2.40%	2.40%
2.05% Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Value	$ 9,270	$ 14,737
Fair Value	$ 9,356	$ 14,873
Interest rate on debt	2.05%	2.05%
1.30% Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Value	$ 2,895	$ 4,382
Fair Value	$ 2,903	$ 4,384
Interest rate on debt	1.30%	1.30%
1.55% Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Value	$ 5,674	$ 7,143
Fair Value	$ 5,727	$ 7,210
Interest rate on debt	1.55%	1.55%
1.10% Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Value	$ 10,527	$ 0
Fair Value	$ 10,520	$ 0
Interest rate on debt	1.10%	1.10%

Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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