Stockholders' Equity (Deficit) - Additional Information (Details)	12 Months Ended
	Feb. 28, 2017 USD ($) vote $ / shares shares	Feb. 29, 2016 USD ($) $ / shares shares	Feb. 28, 2015 USD ($)	Sep. 30, 2015 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common and preferred shares authorized (in shares) | shares	1,020,000,000
Common stock, shares authorized (in shares) | shares	1,000,000,000	1,000,000,000
Common stock, par value (in usd per share) | $ / shares	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares) | shares	20,000,000	20,000,000
Preferred stock, par value (in usd per share) | $ / shares	$ 0.001	$ 0.001
Common stock voting rights	Voting Rights—Holders of our common stock are entitled to one vote for each share held on all matters submitted to a vote of stockholders.
Voting rights, number of votes | vote	1
Options granted are exercisable for periods	10 years
Grant-date fair value of stock options vested	$ 7,900,000	$ 10,500,000	$ 7,500,000
Aggregate intrinsic value of stock option awards exercised	$ 5,100,000	$ 8,600,000	$ 33,100,000
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, aggregate purchase price				$ 50,000,000.0
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected period for recognizing compensation expense	2 years 8 months 14 days
Unrecognized compensation cost related to unvested RSUs	$ 49,000,000
Restricted Stock Units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options and RSUs granted vesting period	3 years
Restricted Stock Units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options and RSUs granted vesting period	4 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to outstanding stock options	$ 9,200,000
Expected period for recognizing compensation expense	1 year 11 months 3 days
Stock Options | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options and RSUs granted vesting period	3 years
Stock Options | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options and RSUs granted vesting period	4 years
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award, offering period	6 months
Purchase price of stock, percent of lower of fair market value	85.00%
Common stock, reserved for issuance under the Employee Stock Purchase Program (in shares) | shares	673,745