Earnings Per Share (Schedule Of Earnings Per Share, Basic And Diluted) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Numerator
Net income	$ 13,342	$ 10,583	$ 34,467	$ 26,732
Less: Undistributed earnings allocated to participating securities	(241)	(358)	(785)	(890)
Net income allocable to common stockholders	$ 13,101	$ 10,225	$ 33,682	$ 25,842
Denominator
Weighted average common shares outstanding - basic	20,673,521	20,601,218	20,643,682	20,556,146
Dilutive effect of restricted stock units	148,545		88,248
Weighted average common shares outstanding - diluted	20,822,066	20,601,218	20,731,930	20,556,146
Earnings per share:
Basic	$ 0.63	$ 0.50	$ 1.63	$ 1.26
Diluted	$ 0.63	$ 0.50	$ 1.62	$ 1.26