Earnings Per Share (Schedule of Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	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
Earnings Per Share [Abstract]
Net income	$ (1,080)	$ 2,553	$ 4,958	$ 4,011	$ (7,351)	$ 2,438	$ 7,723	$ 8,009	$ 10,442	$ 10,819	$ 18,463
Weighted-average shares outstanding - basic									51,907,619	51,700,045	51,418,600
Dilutive common stock equivalents									181,541	227,832	461,513
Weighted-average shares outstanding - diluted									52,089,160	51,927,877	51,880,113
Basic net income per share	$ (0.02)	$ 0.05	$ 0.10	$ 0.08	$ (0.14)	$ 0.05	$ 0.15	$ 0.16	$ 0.20	$ 0.21	$ 0.36
Diluted net income per share	$ (0.02)	$ 0.05	$ 0.10	$ 0.08	$ (0.14)	$ 0.05	$ 0.15	$ 0.15	$ 0.20	$ 0.21	$ 0.36
Antidilutive Shares									1,508,616	445,490	373,255