Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net loss	$ (32,201)	$ (29,938)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	8,533	7,017
Stock-based compensation expense	15,601	10,247
Other	508	700
Changes in operating assets and liabilities:
Accounts receivable	5,492	(7,166)
Prepaid expenses and other assets	(2,758)	(3,809)
Accounts payable	757	133
Accrued compensation and benefits and other liabilities	(743)	2,454
Deferred revenue	5,654	16,076
Deferred rent	2,994	157
Net cash provided by (used in) operating activities	3,837	(4,129)
Cash flows from investing activities:
Purchases of property and equipment	(8,490)	(6,608)
Increase in restricted cash	0	(3,400)
Purchases of short-term investments	(65,404)	(53,422)
Proceeds from sale and maturity of short-term investments	87,415	28,350
Capitalized software development costs	(1,733)	(4,096)
Net cash provided by (used in) investing activities	11,788	(39,176)
Cash flows from financing activities:
Proceeds from employee stock purchase plan	2,504	0
Proceeds from exercise of employee stock options	9,902	6,844
Net cash provided by financing activities	12,406	6,844
Net increase (decrease) in cash and cash equivalents	28,031	(36,461)
Cash and cash equivalents, beginning of period	65,914	105,257
Cash and cash equivalents, end of period	93,945	68,796
Supplemental disclosure of cash flow information:
Cash paid for interest and income taxes	102	76
Noncash investing and financing activities:
Property and equipment purchased but not yet paid	$ 5,808	$ 900