Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities:
Net loss	$ (46,084)	$ (48,293)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	13,356	11,058
Stock-based compensation expense	23,719	16,603
Other	822	817
Changes in operating assets and liabilities, net of acquisition of business:
Accounts receivable	(6,478)	(10,010)
Prepaid expenses and other assets	(1,651)	(1,265)
Accounts payable	1,125	859
Accrued compensation and benefits and other liabilities	3,307	4,068
Deferred revenue	18,169	28,750
Deferred rent	3,052	199
Net cash provided by operating activities	9,337	2,786
Cash flows from investing activities:
Purchases of property and equipment	(16,601)	(8,119)
Acquisition of business, net of cash acquired	0	(5,498)
Increase in restricted cash	0	(3,400)
Purchases of short-term investments	(116,285)	(80,046)
Proceeds from sale and maturity of short-term investments	126,113	55,692
Capitalized software development costs	(3,075)	(5,316)
Net cash used in investing activities	(9,848)	(46,687)
Cash flows from financing activities:
Proceeds from employee stock purchase plan	2,504	0
Proceeds from exercise of employee stock options	12,263	10,545
Net cash provided by financing activities	14,767	10,545
Net increase (decrease) in cash and cash equivalents	14,256	(33,356)
Cash and cash equivalents, beginning of period	65,914	105,257
Cash and cash equivalents, end of period	80,170	71,901
Supplemental disclosure of cash flow information:
Cash paid for interest and income taxes	226	76
Noncash investing and financing activities:
Issuance of common stock for the acquisition of business	0	6,777
Property and equipment purchased but not yet paid	$ 2,534	$ 1,227