(Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Numerator
Net income	$ 26,173	$ 16,732
Denominator
Denominator for basic earnings per share — weighted average shares outstanding	52,548	51,956
Dilutive effect of unvested restricted common stock (including restricted stock units) and options issued to employees and directors	410	577
Denominator for diluted earnings per share (in shares)	52,958	52,533
Earnings per Common Share:
Basic net earnings per share (in USD per share)	$ 0.50	$ 0.32
Diluted net earnings per share (in USD per share)	$ 0.49	$ 0.32