Employee stock purchase plan offering period.

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- Definition

Number of equity compensation plans.

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No definition available.

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- Definition

Payments for repurchase of common stock and fully vested stock option.

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No definition available.

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- Definition

Share based compensation arrangement by share based payment award non option equity instruments granted weighted average grant date fair value..

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No definition available.

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- Definition

Share cap for ESPP at each purchase date.

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No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

When presenting a range of interest rates, the highest effective rate for funds borrowed under the debt agreement as of the balance sheet date.

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When presenting a range of interest rates, the lowest effective rate for funds borrowed under the debt agreement as of the balance sheet date.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The number of grants made 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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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

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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No definition available.

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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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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.

+ References

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- Definition

Net number of share options (or share units) granted during the period.

+ References

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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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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

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

+ References

No definition available.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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No definition available.

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- Definition

Amount of capitalized and expensed compensation cost from equity-based compensation arrangements.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 share options (or share units) exercised during the current period.

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- Definition

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Value of stock issued as a result of the exercise of stock options.

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- Definition

Amount of stock repurchase plan authorized.

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No definition available.

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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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No definition available.

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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity Incentive Plans - Additional Information (Details)			1 Months Ended	12 Months Ended
	Jul. 31, 2014 USD ($) shares	Nov. 30, 2013 USD ($) shares	Aug. 31, 2015 USD ($) shares	Jan. 31, 2016 USD ($) Plan $ / shares shares	Jan. 31, 2015 USD ($) $ / shares shares	Jan. 31, 2014 USD ($) $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of equity incentive plans \| Plan				2
Shares reserved for future issuance \| shares				97,716,887
Fair market value of Class A common stock				$ 455,138,000
Issuance of common stock upon exercise of stock options (in shares) \| shares				2,313,598
Promissory note amount outstanding					$ 4,000,000
Issuance of common stock upon exercise of stock options						$ 336,000
Unrecognized compensation cost				$ 201,800,000
Unrecognized compensation cost related to stock awards, weighted-average period				3 years 8 months 12 days
Stock-based compensation expense				$ 58,225,000	$ 53,033,000	$ 21,566,000
Number of options granted \| shares				19,269,524
Payment for repurchase of common stock and vested stock options	$ 57,700,000	$ 20,500,000
Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair market value of Class A common stock				$ 3,000
Issuance of common stock upon exercise of stock options (in shares) \| shares						4,047,000
Unvested stock option, common stock repurchased during the period \| shares					3,803,000	3,046,000
Issuance of common stock upon exercise of stock options						$ 0
Repurchase of shares \| shares	735,426	1,442,098
Accumulated Deficit
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair market value of Class A common stock				$ 0
Issuance of common stock upon exercise of stock options						0
Repurchase of recorded in accumulated deficit	$ 30,100,000	$ 7,200,000
Tender Offer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Proceeds from stock options exercised	$ 2,100,000	$ 640,000
Repurchase Of Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense					$ 27,600,000	$ 13,300,000
Promissory Notes
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock upon exercise of stock options (in shares) \| shares						6,295,056
Fixed interest rate ,minimum				0.95%
Fixed interest rate ,maximum				1.84%
Promissory note amount outstanding						$ 3,200,000
Nonrecourse Promissory Note
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock upon exercise of stock options (in shares) \| shares					300,000
Issuance of common stock upon exercise of stock options					$ 773,000
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance \| shares				25,337,800
Intrinsic value of exercised options				$ 29,500,000	$ 43,200,000	$ 8,500,000
Weighted-average grant date fair value of options granted \| $ / shares				$ 8.38	$ 5.71	$ 1.50
Total grant date fair value of options vested				$ 35,400,000	$ 9,900,000	$ 3,500,000
Repurchase of shares \| shares	3,067,910	1,603,536
Employee Stock Option \| Early Exercise of Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock upon exercise of stock options (in shares) \| shares				0	642,248
Proceeds from stock options exercised					$ 1,900,000
Unvested stock option, common stock repurchased during the period \| shares				15,000	50,000
Common stock subject to repurchase \| shares				2,809,264	4,710,454
Common stock subject to repurchase, aggregate price				$ 4,800,000	$ 6,500,000
Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options granted, net of cancellations \| shares				238,000	499,750	3,883,654
Stock-based compensation expense				$ 2,500,000	$ 1,700,000	$ 596,000
Non Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense				$ 3,100,000	$ 2,500,000	$ 1,100,000
Number of options granted \| shares				22,500	83,500	1,126,400
Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity awards of vest period				4 years
Common Stock Shares Issued \| shares				18,300,000
Weighted-average grant date fair market value \| $ / shares				$ 0.0005
Share-based compensation, number of shares vested \| shares						2,812,500
2015 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity awards of vest expire period				10 years
2015 Equity Incentive Plan \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price as percentage of fair market value of common stock				100.00%
Equity awards of vest period				2 years
2015 Equity Incentive Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity awards of vest period				4 years
2015 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance \| shares				3,500,000
Employee stock purchase plan offering period			24 months
Fair market value of Class A common stock			$ 17.00
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense				$ 4,400,000
Unrecognized stock-based compensation expense				$ 21,600,000
Stock-based Compensation Expense Related to Tender Offer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 27,600,000	$ 13,300,000
Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Closing price of stock \| $ / shares				$ 13.01
Class A Common Stock \| 2015 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares initially reserved for issuance \| shares				27,000,000
Increase in shares reserved by percentage of capital stock				5.00%
Shares reserved for future issuance \| shares				25,337,800
Class A Common Stock \| 2015 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price as percentage of fair market value of common stock			85.00%
Shares reserved for future issuance \| shares			3,500,000
Payroll deductions percentage			30.00%
Share cap for ESPP at purchase date \| shares			3,000
Calendar year gap for ESPP contribution amount			$ 25,000