Debt and Financing Arrangements (Long term Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Debt issuance costs	$ (10,959)	$ (10,873)
Total	555,033	508,312
Less: current maturities of debt	138,587	31,097
Long-term debt	416,446	477,215
Term loan due 2024
Debt Instrument [Line Items]
Long-term debt	285,943	288,033
Debt instrument, face amount	286,500
Tax Exempt Bonds
Debt Instrument [Line Items]
Long-term debt	98,075	53,090
Debt instrument, face amount	98,100
Convertible Debt
Debt Instrument [Line Items]
Long-term debt	119,979	115,367
Debt instrument, face amount	155,300
Other Debt
Debt Instrument [Line Items]
Long-term debt	$ 61,995	$ 62,695

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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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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Amount, before 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 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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