Number of shares of common stock outstanding increase percentage.

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Equity Incentive Plans

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Purchase Offering Period

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No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

+ References

No definition available.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&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.

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No definition available.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6415400&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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Equity Awards - Additional Information (Detail) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($) shares	Mar. 31, 2017 shares	Jun. 30, 2017 USD ($) incentive_plan $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Equity Incentive Plans \| incentive_plan			2
Weighted-average grant date fair value of options granted (usd per share) \| $ / shares			$ 37.57
Fair value of stock options vested \| $			$ 5.3
Number of shares, granted	50,000	566,720
Total unrecognized compensation cost, adjusted for estimated forfeitures, related to unvested stock options \| $	$ 33.8		$ 33.8
Options outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining weighted-average period			3 years 6 months 18 days
Options outstanding \| New President and CEO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted			396,720
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining weighted-average period			2 years 10 months 28 days
Unrecognized compensation expense expected to be recognized \| $	$ 737.9		$ 737.9
2012 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock outstanding, increase, percentage			5.00%
Number of additional shares authorized			8,371,539
2012 Equity Incentive Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense recognized, vesting term			4 years
2012 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock outstanding, increase, percentage			1.00%
Number of additional shares authorized			1,674,308
Common stock purchase price percentage			85.00%
Award offering period			6 months