Debt - Schedule of Debt (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Principal Payments
Debt discounts and deferred financing costs	$ (9,400,000)	$ (3,000,000.0)
Total debt	195,500,000	200,800,000
Less: Debt payable within one year	4,800,000	2,600,000
Long-term debt	$ 190,700,000	198,200,000
Senior notes \| 2021 Senior Notes (5.25% fixed rate) redeemed July 2020
Principal Payments
Fixed rate of interest	5.25%
Total debt	$ 0	175,000,000.0
Line of credit \| Term B Loan
Principal Payments
Total debt	199,500,000	0
Line of credit \| Global Revolving Credit Facility (variable rates) due December 2023
Principal Payments
Total debt	$ 0	21,600,000
Secured debt \| German loan agreement (2.45% fixed rate) due in quarterly installments ending September 2022
Principal Payments
Fixed rate of interest	2.45%
Total debt	$ 2,600,000	3,500,000
Secured debt \| German loan agreement
Principal Payments
Fixed rate of interest	1.45%
Total debt	$ 2,800,000	$ 3,700,000

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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