Components of beginning debt balance [Abstract]

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Components of ending debt balance [Abstract]

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Debt Borrowing, Repayment, Amortization during period [Abstract]

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Long-term Line of Credit, Gross

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Proceeds from Long-term Lines of Credit, Finance Costs

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Proceeds from Long-term Lines of Credit, Net of Financing Costs

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Repayments of Lines of Credit, Net of Financing Costs

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- Definition

Amount of amortization expense attributable to debt issuance costs.

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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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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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The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt and Credit Agreements - Schedule of Debt (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Debt Borrowing, Repayment, Amortization during period [Abstract]
Repayment of debt and revolving credit facility			$ (60,000)	$ (27,000)
Amortization of deferred issuance cost	$ 600	$ 600	1,718	$ 1,718
Wells Fargo Bank, National Association
Components of beginning debt balance [Abstract]
Debt under credit facilities at beginning of period			140,000
Deferred issuance cost, net at beginning of period			(4,583)
Total Debt, net of deferred issuance cost at beginning of period			135,417
Debt Borrowing, Repayment, Amortization during period [Abstract]
Proceeds from lines of credit			0
Deferred issuance cost, gross			0
Increase in borrowings net of deferred issuance cost			0
Repayment of debt and revolving credit facility			(60,000)
Amortization of deferred issuance cost			1,718
Decrease in repayment/amortization net of deferred issuance cost			(58,282)
Components of ending debt balance [Abstract]
Debt under credit facilities at end of period	80,000		80,000
Deferred issuance cost, net at end of period	(2,865)		(2,865)
Total Debt, net of deferred issuance cost at end of period	77,135		135,417
Wells Fargo Bank, National Association \| Term loan facility
Components of beginning debt balance [Abstract]
Debt under credit facilities at beginning of period			140,000
Debt Borrowing, Repayment, Amortization during period [Abstract]
Proceeds from lines of credit			0
Repayment of debt and revolving credit facility			(60,000)
Components of ending debt balance [Abstract]
Debt under credit facilities at end of period	80,000		80,000
Wells Fargo Bank, National Association \| Revolving credit facility
Components of beginning debt balance [Abstract]
Debt under credit facilities at beginning of period			0
Debt Borrowing, Repayment, Amortization during period [Abstract]
Proceeds from lines of credit			0
Repayment of debt and revolving credit facility			0
Components of ending debt balance [Abstract]
Debt under credit facilities at end of period	$ 0		$ 0