Stock-Based Compensation - Nonvested Options (Details) - $ / shares	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Shares
Nonvested options at beginning of period (in shares)	2,010,346
Granted (in shares)	154,934	564,666	1,176,205
Vested (in shares)	(1,330,544)
Canceled/Forfeited (in shares)	(61,501)
Nonvested options at end of period (in shares)	773,235	2,010,346
Weighted Avg. Exercise Price
Nonvested options at beginning of period (in dollars per share)	$ 23.61
Granted (in dollars per share)	27.50	$ 28.88	$ 23.17
Vested (in dollars per share)	22.31
Canceled/Forfeited (in dollars per share)	26.42
Nonvested options at end of period (in dollars per share)	$ 26.41	$ 23.61