Stock-based Compensation Restricted Stock Unit Activity (Details)	9 Months Ended
	Dec. 31, 2016 $ / shares shares	Mar. 31, 2016
Stock-based Compensation Restricted Stock Unit Activity Details
Balance at beginning of period | shares	4,544,799
Granted | shares	2,115,744
Vested | shares	(1,351,014)
Forfeited | shares	(284,431)
Balance at end of period | shares	5,025,098
RSU weighted-average remaining contractual term, in years	1.66	1.67
Beginning of period, weighted-average grant date fair value | $ / shares	$ 5.09
Granted, weighted-average grant date fair value | $ / shares	15.07
Vested, weighted-average grant date fair value | $ / shares	7.99
Forfeited, weighted-average grant date fair value | $ / shares	9.35
End of period, weighted-average grant date fair value | $ / shares	$ 10.99