Earnings Per Share (Computation of Basis and Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Numerator
Net income	$ 43,706	$ 33,925
Denominator
Denominator for basic earnings per share — weighted average shares outstanding (in shares)	50,264	51,697
Dilutive effect of nonvested restricted stock units and options issued to employees and directors (in shares)	544	350
Denominator for diluted earnings per share (in shares)	50,808	52,047
Earnings per Common Share:
Basic earnings per share (in USD per share)	$ 0.87	$ 0.66
Diluted earnings per share (in USD per share)	$ 0.86	$ 0.65