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

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Fair value of the amount outstanding under the credit facility.

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Long-term Debt, Line of Credit and Derivatives - Provisions of the term loan (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Current portion of debt	$ 3,000
Periodic payment, principal	1,500
Repayments of debt	29,500	$ 11,750
Long-term debt, excluding current maturities	54,000
Term Loan \| Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 60,000
Fair value of amount outstanding	$ 57,000
Term Loan \| Line of Credit \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Interest rate, effective percentage	5.94%