Long-Term Indebtedness (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Unamortized deferred financing fees	$ (11,214)	$ (11,988)
Long-term debt	1,286,487	1,302,962
Less current portion	(21,108)	(71,003)
Long-term debt, excluding current maturities	1,265,379	1,231,959
Convertible Notes
Debt Instrument [Line Items]
Long-term debt, gross	460,000	460,000
Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	442,506	403,953
Term Loan
Debt Instrument [Line Items]
Long-term debt, gross	390,000	395,000
Shelf Loan
Debt Instrument [Line Items]
Long-term debt, gross	0	50,000
Other
Debt Instrument [Line Items]
Long-term debt, gross	$ 5,195	$ 5,997

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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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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