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Number of unvested shares to be repurchased.

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Stock options exercised liability recorded.

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Aggregate number of common shares reserved for future issuance.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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Unrecognized cost of unvested options awarded to employees as compensation.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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The increase or decrease in number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding, including vested options.

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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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Percentage of vesting of share-based compensation awards.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Purchase price of common stock expressed as a percentage of its fair value.

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Number of shares issued which are neither cancelled nor held in the treasury.

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Number of shares of stock issued during the period pursuant to acquisitions.

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Stock-Based Compensation - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 31, 2015	Oct. 31, 2014	Oct. 31, 2015	Oct. 31, 2014	Jan. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Description of offering period excluding initial offering period			the offering period resets and the new lower price becomes the new offering price for a new 24 month offering period
Liabilities related to early exercises of stock options	$ 29,000		$ 29,000		$ 286,000
Unvested shares subject to repurchase	25,416		25,416		113,541
Aggregate intrinsic value of exercised options			$ 20,500,000	$ 16,600,000
Aggregate estimated fair value of stock options granted to employees vested			$ 13,500,000	$ 12,600,000
Weighted-average grant date fair value of options granted to employees			$ 6.72	$ 7.96
Unrecognized stock-based compensation expense related to stock option	$ 34,300,000		$ 34,300,000
Remaining weighted-average period			2 years 6 months 29 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining weighted-average period			3 years 2 months 23 days
Unrecognized stock-based compensation expense	120,400,000		$ 120,400,000
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining weighted-average period			1 year 9 months 4 days
Unrecognized stock-based compensation expense	$ 2,900,000		$ 2,900,000
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividend yield	0.00%	0.00%	0.00%	0.00%
2015 Equity Incentive Plan \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares common stock reserved for issuance	13,408,455		13,408,455
2015 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares common stock reserved for issuance	2,761,742		2,761,742
Percentage of eligible compensation allowed to employees to purchase shares at a discount					15.00%
Description of offering period excluding initial offering period			Except for the initial offering period, the 2015 ESPP provides for 24-month offering periods beginning March 16 and September 16 of each year, and each offering period will consist of four six-month purchase periods.
Purchase price of common stock, percentage			85.00%
Unrecognized stock-based compensation expense	$ 14,800,000		$ 14,800,000
2015 Employee Stock Purchase Plan \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining weighted-average period			1 year 10 months 2 days
Unrecognized stock-based compensation expense	$ 2,600,000		$ 2,600,000
Shares issued in connection with fiscal 2015 acquisitions					344,667
Restricted shares outstanding	342,187		342,187
2015 Employee Stock Purchase Plan \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares common stock reserved for issuance					2,500,000
Shares common stock, increase			2,500,000
Shares common stock, outstanding shares of capital stock			1.00%
Other Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares common stock reserved for issuance	81,572		81,572
Remaining weighted-average period			1 year 7 months 21 days
Unrecognized stock-based compensation expense	$ 900,000		$ 900,000
Vesting Commencement Per Year \| 2015 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options and restricted stock units vesting percentage			25.00%
Vesting Commencement Per Month
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options and restricted stock units vesting percentage			2.08%
Vesting Commencement Per Quarter
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options and restricted stock units vesting percentage			6.25%