Debt and Credit Agreements - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total debt obligations	$ 784,161	$ 605,394
Less: deferred financing costs	(17,367)	(13,243)
Total debt obligations, net of deferred financing costs	766,794	592,151
Less: current maturities of long-term debt	(2,540)	(6,489)
Long-term debt	764,254	585,662
Term Loan Facility
Debt Instrument [Line Items]
Total debt obligations	$ 218,188	541,788
Unsecured Notes \| 5.75% Notes, due 2027
Debt Instrument [Line Items]
Fixed rate	5.75%
Total debt obligations	$ 500,000	0
Other financing payable (including finance leases) in varying amounts due principally through 2019
Debt Instrument [Line Items]
Total debt obligations	8,973	1,606
Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Total debt obligations	$ 57,000	$ 62,000

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 classified as noncurrent. 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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