Employee stock purchase plan offering period.

No definition available.

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- Definition

Number of equity compensation plans.

+ References

No definition available.

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- Definition

Number of Purchase Periods

+ References

No definition available.

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- Definition

Purchase Period, Term

+ References

No definition available.

+ Details

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- Definition

Share cap for ESPP at each purchase date.

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Dollar Cap Per Purchase Period

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Balance Type:	debit
Period Type:	duration

- References

No definition available.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Period Type:	instant

- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Balance Type:	na
Period Type:	instant

- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)(iii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

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

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of cost expensed and capitalized for award under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

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

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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Equity Incentive Plans - Narrative (Details)		1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
Equity Incentive Plans - Narrative (Details)	Mar. 16, 2016	Feb. 28, 2019 USD ($)	Jul. 31, 2019 USD ($) $ / shares	Jul. 31, 2018 USD ($)	Jul. 31, 2019 USD ($) plan $ / shares	Jul. 31, 2018 USD ($)	Dec. 31, 2015 USD ($) period shares	Apr. 04, 2018 $ / shares
Share-based Payment Arrangement [Abstract]
Number of equity incentive plans \| plan					2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Closing price of stock (in dollars per share) \| $ / shares			$ 15.14		$ 15.14
Total stock-based compensation expense			$ 58,404,000	$ 53,654,000	$ 120,561,000	$ 97,609,000
Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Closing price of stock (in dollars per share) \| $ / shares			$ 15.14		$ 15.14			$ 19.83
2015 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards of vest expire period (no later than)					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]
Employee stock purchase plan offering period	24 months
Number of purchase periods \| period							4
Purchase period, term							6 months
Total stock-based compensation expense			$ 4,200,000	7,900,000	$ 15,700,000	14,600,000
Unrecognized stock-based compensation expense			19,400,000		$ 19,400,000
Compensation cost (in years)					1 year 6 months
2015 Employee Stock Purchase Plan \| Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price as percentage of fair market value of common stock							85.00%
Payroll deductions percentage							30.00%
Share cap for ESPP at purchase date (in shares) \| shares							3,000
Calendar year gap for ESPP contribution amount							$ 25,000
Dollar cap per purchase period		$ 7,500
Modification charges					$ 2,200,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense			7,400,000	$ 6,700,000	14,800,000	$ 10,200,000
Unrecognized stock-based compensation expense			$ 30,600,000		$ 30,600,000
Compensation cost (in years)					2 years 3 months 18 days