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Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

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Amount of unrecognized tax benefits.

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Amount of interest expense accrued for an underpayment of income taxes.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes - Accounting for Uncertainty in Income Taxes (Details Textual) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes (Textual) [Abstract]
Liability for unrecognized tax benefits	$ 1,891	$ 1,668				$ 1,915				$ 1,668	$ 1,915	$ 1,891	$ 4,079
Income tax related to accrued interest, net of federal benefit	400	600				500				600	500	400
Unrecognized tax benefits that would favorably impact the tax rate		1,700								1,700
Income tax benefit		4,669	$ 4,391	$ 5,607	$ 6,190	$ 6,705	$ 8,806	$ 8,722	$ 2,113	20,857	26,346	$ 37,117
ASU 2016-09
Income Taxes (Textual) [Abstract]
Income tax benefit										(1,000)	$ 3,000
Internal Revenue Service (IRS)
Income Taxes (Textual) [Abstract]
Additional Income tax payment on audit for 2010 through 2012 tax year	$ 8,000
Maximum
Income Taxes (Textual) [Abstract]
Unrecognized tax benefits decrease amount over next twelve months		$ 400								$ 400