Share-Based Compensation - Summary of Share-based Compensation Activity (Details)	6 Months Ended
	Sep. 30, 2017 shares
Options
Number of Options
Outstanding at beginning of period (in shares)	4,791,045
Granted (in shares)	208,264
Exercised (in shares)	(405,951)
Canceled/forfeited (in shares)	(58,309)
Outstanding at end of period (in shares)	4,535,049
Restricted Shares
Number of Unvested Restricted Shares
Unvested at beginning of period (in shares)	185,425
Granted (in shares)	0
Vested (in shares)	(102,908)
Decrease due to performance condition (in shares)	0
Canceled/forfeited (in shares)	(4,076)
Unvested at end of period (in shares)	78,441
Service-Based RSUs
Number of Unvested Restricted Shares
Unvested at beginning of period (in shares)	1,470,767
Granted (in shares)	1,086,859
Vested (in shares)	(385,286)
Decrease due to performance condition (in shares)	0
Canceled/forfeited (in shares)	(36,688)
Unvested at end of period (in shares)	2,135,652
Performance-Based RSUs
Number of Unvested Restricted Shares
Unvested at beginning of period (in shares)	401,777
Granted (in shares)	139,562
Vested (in shares)	(81,212)
Decrease due to performance condition (in shares)	(12,891)
Canceled/forfeited (in shares)	0
Unvested at end of period (in shares)	447,236