Stockholders' Equity Restricted Stock Unit Activity (Details)	12 Months Ended
	Mar. 31, 2017 $ / shares shares	Mar. 31, 2016 $ / shares shares	Mar. 31, 2015 $ / shares shares	Mar. 31, 2014
Stockholders Equity Restricted Stock Unit Activity Details
Balance at beginning of period | shares	4,544,799	2,698,686	1,134,856
Granted | shares	2,491,877	2,681,997	1,965,786
Vested | shares	(1,600,831)	(589,788)	(187,788)
Forfeited | shares	(496,795)	(246,096)	(214,168)
Balance at end of period | shares	4,939,050	4,544,799	2,698,686
RSU weighted-average remaining contractual term, in years	2.47	1.67	1.88	2.00
Beginning of period, weighted-average purchase price | $ / shares	$ 8.08	$ 7.33	$ 9.00
Granted, weighted-average purchase price | $ / shares	15.15	8.78	6.68
Vested, weighted-average purchase price | $ / shares	7.89	7.79	9.54
Forfeited, weighted-average purchase price | $ / shares	9.56	8.15	8.30
End of period, weighted-average purchase price | $ / shares	$ 11.57	$ 8.08	$ 7.33