Stock-Based Employee Compensation (Stock Option Activity) (Details) - Employee Stock Option shares in Thousands	9 Months Ended
	Dec. 31, 2017 $ / shares shares
Shares
Beginning stock options outstanding (in shares) | shares	1,374
Exercised (in shares) | shares	(225)
Canceled (in shares) | shares	(15)
Ending stock options outstanding (in shares) | shares	1,134
Ending stock options exercisable (shares) | shares	968
Price
Beginning stock options outstanding (in dollars per share) | $ / shares	$ 13.01
Exercised (in dollars per share) | $ / shares	8.46
Canceled (in dollars per share) | $ / shares	23.86
Ending stock options outstanding (in dollars per share) | $ / shares	13.78
Ending stock options exercisable (in dollars per share) | $ / shares	$ 12.70