Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Face (par) amount of debt instrument at time of issuance.

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

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Weighted average interest rate of debt outstanding.

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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 of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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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 cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Debt (Narrative) (Details) - USD ($)	3 Months Ended
Debt (Narrative) (Details) - USD ($)	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Aug. 14, 2020	Dec. 21, 2016
Debt [Line Items]
Repayment of debt	$ 2,626,000	$ 4,236,000
Senior Unsecured Notes [Member]
Debt [Line Items]
Unamortized deferred debt issue costs	$ 6,823,000		$ 7,266,000
Revolving Credit Facility [Member]
Debt [Line Items]
Weighted average interest rate	2.50%		2.30%
Third Amendment of the Credit Agreement [Member]
Debt [Line Items]
Maximum borrowing capacity				$ 630,000,000.0
Committed Revolving Credit Facilities [Member]
Debt [Line Items]
Maximum borrowing capacity	$ 461,115,000
Available borrowing capacity	456,115,000
5.375% Senior Unsecured Note, Due January 2025 [Member] \| Senior Unsecured Notes [Member]
Debt [Line Items]
Principal amount					$ 500,000,000
Outstanding debt	$ 500,000,000		$ 500,000,000
Interest rate	5.375%				5.375%
Maturity date	Jan. 15, 2025
Revolving Credit Facility [Member] \| Committed Revolving Credit Facilities [Member]
Debt [Line Items]
Maturity date	Oct. 27, 2023
Multicurrency Revolving Facilities [Member] \| Third Amendment of the Credit Agreement [Member]
Debt [Line Items]
Maximum borrowing capacity				530,000,000
Delayed-draw Term Loan Facility [Member] \| Third Amendment of the Credit Agreement [Member]
Debt [Line Items]
Maximum borrowing capacity				$ 100,000,000