Earnings per Common Share - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share, Basic [Abstract]
Net income	$ 9,941	$ 5,914
Weighted average shares outstanding - basic (shares)	26,476	26,470
Basic EPS (US$ per share)	$ 0.38	$ 0.22
Earnings Per Share, Diluted [Abstract]
Dilutive stock options	86	147
Dilutive nonvested deferred shares	488	517
Diluted weighted average shares (shares)	27,050	27,134
Diluted EPS (US$ per share)	$ 0.37	$ 0.22