Description of offering period.

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- Definition

Number of unvested shares to be repurchased.

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No definition available.

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- Definition

Stock options exercised liability recorded.

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No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

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- Definition

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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

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- Definition

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

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No definition available.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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- Definition

A description of the time period when the company made its initial offering of a class of securities.

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No definition available.

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- Definition

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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- Definition

Percentage of vesting of share-based compensation awards.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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- Definition

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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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-Subparagraph (f)(2)(iii)

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- Definition

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

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- Definition

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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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 2

-Subparagraph (d)(2)

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- Definition

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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- Definition

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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- Definition

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

+ References

No definition available.

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- Definition

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

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

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-Subparagraph (SX 210.3-04)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Stock-Based Compensation - Additional Information (Details) (USD $)	3 Months Ended
	Apr. 30, 2015	Apr. 30, 2014	Jan. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Liabilities related to early exercises of stock options	$ 98,000		$ 286,000
Unvested shares subject to repurchase	67,499		113,541
Aggregate intrinsic value of exercised options	5,300,000	11,000,000
Aggregate estimated fair value of stock options granted to employees vested	6,100,000	4,400,000
Weighted-average grant date fair value of options granted to employees	$ 7.70	$ 8.66
Unrecognized stock-based compensation expense related to stock option	34,700,000
Remaining weighted-average period	2 years 7 months 24 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining weighted-average period	3 years 5 months 19 days
Unrecognized stock-based compensation expense	101,100,000
Weighted-Average Grant Date Fair Value, Granted	$ 17.54
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining weighted-average period	2 years 2 months 9 days
Unrecognized stock-based compensation expense	4,000,000
Shares issued in connection with fiscal 2016 acquisitions	2,500
Weighted-Average Grant Date Fair Value, Granted	$ 17.54
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividend yield	0.00%	0.00%
2015 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options and restricted stock units vesting percentage	25.00%
Options and restricted stock units vesting description	Options and restricted stock units generally vest 25% one year from the vesting commencement date and (a) in the case of options, 1/48th per month thereafter, and (b) in the case of restricted stock units, 1/16th per quarter thereafter
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	16,331,626		12,200,000
2015 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares common stock reserved for issuance	3,696,550
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.
Description of initial offering period	The initial offering period began January 23, 2015, and will end on March 15, 2017.
Purchase price of common stock, percentage	85.00%
Unrecognized stock-based compensation expense	13,400,000
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
Other Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares common stock reserved for issuance	163,619
Remaining weighted-average period	2 years 1 month 21 days
Unrecognized stock-based compensation expense	$ 1,400,000