CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jul. 31, 2013	Jul. 31, 2012
Cash flows from operating activities
Net loss	$ (29,827)	$ (25,045)
Adjustments to reconcile net loss to net cash provided by operating activities
Depreciation and amortization	2,880	2,149
Change in fair value of preferred stock warrants	0	14,087
Stock-based compensation expense	21,792	6,538
Excess tax benefit from employee stock plans	(268)	0
Changes in operating assets and liabilities
Accounts receivable, net	23,202	814
Prepaid expenses, other current and non-current assets	(3,597)	(1,172)
Accounts payable	(147)	300
Accrued compensation	(6,235)	2,563
Accrued expenses and other liabilities	5,379	167
Deferred revenue	12,923	15,003
Net cash provided by operating activities	26,102	15,404
Cash flows from investing activities
Purchases of property and equipment	(3,230)	(3,474)
Net cash used in investing activities	(3,230)	(3,474)
Cash flows from financing activities
Repayments of term debt	0	(2,289)
Proceeds from initial public offering, net of offering costs	0	225,225
Proceeds from exercise of stock options	12,523	1,825
Excess tax benefit from employee stock plans	268	0
Proceeds from employee stock purchase plan	6,076	0
Taxes paid related to net share settlement of equity awards	(513)	0
Net cash provided by financing activities	18,354	224,761
Effect of exchange rate changes on cash and cash equivalents	(51)	(12)
Net increase in cash and cash equivalents	41,175	236,679
Cash and cash equivalents
Beginning of period	305,939	31,599
End of period	347,114	268,278
Supplemental disclosures
Cash paid for interest	0	40
Cash paid for income taxes	246	0
Non-cash investing and financing activities
Accrued purchases of property and equipment	767	656
Vesting of early exercised options	55	754
Conversion of preferred stock to common stock	0	40,913
Deferred offering costs not yet paid	$ 0	$ 999