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Maximum borrowing capacity under the credit facility in non-U.S. currencies without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the faciity.

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Permitted acquisition consideration amount which would allow for a temporary covenant holiday period.

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Amount of dividends and stock repurchases the Company is permitted to fund if its leverage ratio is greater than what is defined in the covenant.

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Amount of other incremental cash payments the Company is permitted to make if its leverage ratio is greater than what is defined in the covenant.

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The cash inflow from early termination of interest rate swap, designated as a cash flow hedge.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Weighted average interest rate of debt outstanding.

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Nominal or face amount used to calculate payments on the derivative asset.

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of unrealized gain (loss) related to the increase or decrease in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income to the extent that the cash flow hedge was determined to be effective.

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Debt - Additional Information (Details)	12 Months Ended
Debt - Additional Information (Details)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jun. 02, 2017 USD ($)
Debt Instrument [Line Items]
Deferred financing costs	$ 0	$ 1,000,000.0	$ 0
Proceeds from early termination of interest rate swap	200,000
Interest rate swap, fair value		900,000
Aggregate maturities of total borrowings due, year one	200,000
Aggregate maturities of total borrowings due, year two	200,000
Aggregate maturities of total borrowings due, year three	100,000
Aggregate maturities of total borrowings due, year four	$ 209,500,000
Weighted average interest rate on short-term borrowings	1.70%
Interest paid	$ 5,400,000	7,800,000	8,700,000
Unrealized (loss) gain on interest rate cash flow hedges, pretax, accumulated other comprehensive income (loss)	(3,900,000)	$ (1,000,000.0)	$ 400,000
Interest rate swap fair value	$ (3,000,000.0)
Interest Rate Swap
Debt Instrument [Line Items]
Line of credit facility, amount outstanding				$ 150,000,000.0
2019 Credit Agreement \| Minimum
Debt Instrument [Line Items]
Line of credit facility, unused capacity, commitment fee percentage	0.10%
2019 Credit Agreement \| Maximum
Debt Instrument [Line Items]
Line of credit facility, unused capacity, commitment fee percentage	0.25%
2019 Credit Agreement \| London Interbank Offered Rate (LIBOR) \| Minimum
Debt Instrument [Line Items]
Base rate borrowings margin ranges	1.00%
2019 Credit Agreement \| London Interbank Offered Rate (LIBOR) \| Maximum
Debt Instrument [Line Items]
Base rate borrowings margin ranges	1.75%
2019 Credit Agreement \| Base Rate \| Minimum
Debt Instrument [Line Items]
Base rate borrowings margin ranges	0.00%
2019 Credit Agreement \| Base Rate \| Maximum
Debt Instrument [Line Items]
Base rate borrowings margin ranges	0.75%
2019 Credit Agreement \| Letter of Credit
Debt Instrument [Line Items]
Secured credit facility	$ 75,000,000
Credit facility outstanding amount	10,300,000
2019 Credit Agreement \| Revolving Credit Facility
Debt Instrument [Line Items]
Secured credit facility	500,000,000
Line of credit facility non-U.S. maximum borrowing capacity	200,000,000
Secured credit facility, available increment	$ 250,000,000
Guaranteed percentage of outstanding voting capital stock	65.00%
Line of credit facility, covenant terms, leverage ratio maximum	3.25
Line of credit facility, amount outstanding	$ 209,400,000
Credit facility outstanding amount	280,300,000
2019 Credit Agreement \| Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Line of credit facility, covenants holiday, permitted acquisition consideration	75,000,000
2019 Credit Agreement \| Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Line of credit facility, covenants, permitted dividends and stock repurchases	35,000,000
Line of credit facility, covenants, permitted other incremental cash payments	50,000,000
Interest Rate Swap
Debt Instrument [Line Items]
Line of credit facility, amount outstanding	75,000,000.0
Interest rate swap, notional amount	$ 75,000,000.0