Long-term Debt and Financing Arrangements - Maturities of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt	$ 337,856	$ 77,190
Less portion due within one year	(10,182)	(277)
Total long-term debt, net of debt issuance costs	$ 327,674	76,913
Term Loan, net of debt issuance costs
Debt Instrument [Line Items]
Debt instrument, effective interest rate (as a percent)	3.87%
Long-term debt	$ 199,471	0
Capital Leases \| Capital Leases
Debt Instrument [Line Items]
Long-term debt	$ 385	590
Revolving Credit Facility \| Revolver Loan
Debt Instrument [Line Items]
Debt instrument, effective interest rate (as a percent)	3.87%
Long-term debt	$ 138,000	$ 76,600
Minimum \| Capital Leases
Debt Instrument [Line Items]
Debt instrument, effective interest rate (as a percent)	1.65%
Maximum \| Capital Leases
Debt Instrument [Line Items]
Debt instrument, effective interest rate (as a percent)	2.09%

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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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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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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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