Share Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares approved for grant (in shares)	500,000
Total compensation cost not yet recognized	$ 3,000
Total compensation cost not yet recognized, period for recognition	2 years 3 months 18 days
Information regarding options exercised [Abstract]
Intrinsic value	$ 78	$ 279
Cash proceeds received	13	66
Tax benefit realized	16	98
Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation expense recognized	400	400
Tax benefit relating to compensation expense recognized	$ 100	$ 100
Stock Options [Member]
Number of Shares [Roll Forward]
Outstanding, beginning balance (in shares)	176,055
Granted (in shares)	0
Exercised (in shares)	(3,800)
Forfeited (in shares)	0
Expired (in shares)	0
Outstanding, ending balance (in shares)	172,255
Vested and expected to vest, period end (in shares)	172,255
Exercisable, period end (in shares)	172,255
Average Exercise Price [Roll Forward]
Outstanding, beginning balance (in dollars per share)	$ 5.24
Exercised (in dollars per share)	3.39
Outstanding, ending balance (in dollars per share)	5.28
Vested and expected to vest, period end (in dollars per share)	5.28
Exercisable, period end (in dollars per share)	$ 5.28
Weighted-Average Remaining Contractual Term (Years) [Abstract]
Outstanding, weighted average remaining contractual term	3 years 9 months 18 days
Vested and expected to vest, weighted-average remaining contractual term	3 years 9 months 18 days
Exercisable, weighted average remaining contractual term	3 years 9 months 18 days
Aggregate Intrinsic Value [Abstract]
Outstanding, aggregate intrinsic value	$ 3,035
Vested and expected to vest, aggregate intrinsic value	3,035
Exercisable, aggregate intrinsic value	$ 3,035
Restricted Stock [Member] | Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock units or restricted shares issued in period (in shares)	2,000
Vesting period	3 years
Non-Vested Restricted Stock and PSUs [Member]
Number of Shares [Roll Forward]
Outstanding, beginning balance (in shares)	290,527
Granted (in shares)	64,406
Vested (in shares)	(95,036)
Forfeited (in shares)	(6,028)
Outstanding, ending balance (in shares)	253,869
Weighted Average Grant Date Fair Value [Roll Forward]
Outstanding, beginning balance (in dollars per share)	$ 15.88
Granted (in dollars per share)	23.58
Vested (in dollars per share)	13.14
Forfeited (in dollars per share)	17.70
Outstanding, ending balance (in dollars per share)	$ 18.82
Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issues as retainer fees (in shares)	2,000	2,000
Non-Employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares approved for grant (in shares)	200,000
Total compensation expense recognized	$ 50	$ 40
Tax benefit relating to compensation expense recognized	$ 10	$ 10
Officers [Member] | Restricted Stock [Member] | Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock units or restricted shares issued in period (in shares)	40,000	50,000
Vesting period	3 years	3 years
Officers [Member] | Performance Stock Units [Member] | Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock units or restricted shares issued in period (in shares)	20,000	20,000
Vesting period	3 years	3 years