Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Supplemental Cash Flow Information [Abstract]
Cash paid for income taxes	$ 8,426	$ 18,763	$ 26,574
Income tax refunds received	17	9	100
Cash paid for interest	2,425	2,486	2,540
Noncash financing and investing activity [Abstract]
Fixed assets acquired (adjusted) related to capital lease and financing obligations	0	1,009	3,890
Increase in financing obligations	$ 0	$ 2,598	$ 5,474

The increase during the period in capital lease obligations due to entering into new capital leases.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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The amount of fixed assets that an Entity acquires in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The amount of cash received during the period as refunds for the overpayment of taxes.

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