Revolving Credit Facility and Long-Term Debt - Principal Balances under Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 03, 2018	Dec. 31, 2017
Line of Credit Facility [Line Items]
Total long-term debt	$ 208,867		$ 278,472
Collateralized debt facility	7,000	$ 7,000	6,959
Less unamortized debt issuance costs	(383)		(487)
Less current portion	22,000		19,459
Long-term portion	186,867		259,013
Term Loan
Line of Credit Facility [Line Items]
Total long-term debt	76,250		85,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Total long-term debt	$ 126,000		$ 187,000

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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+ References

No definition available.

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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.

+ References

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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.

+ References

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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.

+ References

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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