Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Earnings Per Share [Abstract]
Net income	$ 7,461	$ 10,255	$ 13,773	$ 18,881
Basic-weighted average shares outstanding	27,620	27,257	27,603	27,303
Effect of dilutive potential securities	237	496	236	500
Diluted- weighted average shares outstanding	27,857	27,753	27,839	27,803
Basic	$ 0.27	$ 0.38	$ 0.50	$ 0.69
Diluted	$ 0.27	$ 0.37	$ 0.49	$ 0.68