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Debt and Financing Arrangements (Long term Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jul. 02, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt	$ 559,786
Debt issuance costs	(10,873)		$ (5,013)
Total	508,312		310,819
Less: current maturities of debt	31,097		20,753
Long-term debt	477,215		290,066
Term loan due 2024
Debt Instrument [Line Items]
Long-term debt	288,033		290,825
Debt instrument, face amount	288,800
Convertible Debt
Debt Instrument [Line Items]
Long-term debt	115,367
Debt instrument, face amount	155,300
Tax Exempt Bonds
Debt Instrument [Line Items]
Long-term debt	53,090
Debt instrument, face amount	53,100	$ 53,100
Other Debt
Debt Instrument [Line Items]
Long-term debt	$ 62,695		$ 25,007