Stockholders' Equity - Employee Stock Purchase Plan (Details) (Employee Stock Purchase Plan, 2012 Employee Stock Purchase Plan) In Millions, unless otherwise specified	3 Months Ended
	Jun. 30, 2014
Employee Stock Purchase Plan | 2012 Employee Stock Purchase Plan
Class of Stock [Line Items]
Common stock reserved for issuance	1.8
Percentage of purchase price of common stock equal to fair market value	85.00%
Common stock, shares issued, employee stock purchase plan	0
Shares available for future issuance	0.5