Income Taxes - Accounting for Uncertainty in Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes (Textual) [Abstract]
Liability for unrecognized tax benefits	$ 1,540				$ 1,668				$ 1,540	$ 1,668	$ 1,915	$ 1,891
Income tax related to accrued interest, net of federal benefit	600				600				600	600	500
Unrecognized tax benefits that would favorably impact the tax rate	1,500								1,500
Income tax benefit	(1,633)	$ (7,262)	$ (7,458)	$ (6,600)	$ (4,669)	$ (4,391)	$ (5,607)	$ (6,190)	(22,953)	(20,857)	$ (26,346)
ASU 2016-09
Income Taxes (Textual) [Abstract]
Income tax benefit									400	$ 1,000
Maximum
Income Taxes (Textual) [Abstract]
Unrecognized tax benefits decrease amount over next twelve months	$ 300								$ 300