Stock-Based Compensation (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred income tax expense (benefit)	$ (2,151)	$ (1,086)	$ 876
Proceeds from issuance of common stock			100
Intrinsic value of stock options exercised			100
Income tax benefits	$ 1,542	7,180	4,927
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	512,922
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred income tax expense (benefit)	$ 900	400	300
Equity Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefits	$ (100)	(100)	(300)
2011 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	3,105,764
Shares reserved for future issuance	941,749
Number of outstanding awards	1,208,610
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 2,300
Weighted average remaining service period of nonvested awards	2 years 9 months 18 days
Vesting term	5 years
Total intrinsic value of vested RSU's	$ 400	$ 2,300	$ 1,300
Performance-based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 2,200
Weighted average remaining service period of nonvested awards	2 years 2 months 12 days

Aggregate number of common shares reserved for future issuance.

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