Employee stock purchase plan number of purchase periods.

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- Definition

Employee stock purchase plan offering period.

+ References

No definition available.

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- Definition

Employee stock purchase plan purchase period.

+ References

No definition available.

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- Definition

Increase in common stock reserved for future issuance.

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No definition available.

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- Definition

Percentage of stock option exercise price of fair market value of common stock.

+ References

No definition available.

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- Definition

Percentage of voting power of all classes of stock.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award options exercisable rate percentage.

+ References

No definition available.

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- Definition

Stock Issued During Period, Shares, Restricted Stock Award, Grants In Period

+ References

No definition available.

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- Definition

Stock Issued During Period, Shares, Restricted Stock Award, Vested

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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

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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 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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- Definition

The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

No definition available.

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- Definition

The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

No definition available.

+ Details

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

No definition available.

+ Details

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- Definition

The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

No definition available.

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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.

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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
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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

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

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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.

+ Details

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- Definition

Number of shares issued under share-based payment arrangement.

+ References

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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

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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.

+ Details

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- Definition

Number of shares related to Restricted Stock Award forfeited during the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Stock Incentive Plans - Additional Information (Details) $ / shares in Units, $ in Millions		1 Months Ended	12 Months Ended
	Oct. 31, 2016 numberOfPurchasePeriod shares	Oct. 31, 2016 shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted during the period (in shares)			0	20,010	366,928
Shares available for future issuance (in shares)			9,740,557	9,098,512
Expected dividend yield			0.00%
Restricted stock units granted (in shares)			595,915
Restricted stock units vested (in shares)			235,915
Restricted stock units forfeited (in shares)			131,871
Weighted-average grant date fair value of options (in USD per share) \| $ / shares				$ 38.29	$ 32.38
Options Granted (in shares)			0
Intrinsic value of options exercised \| $			$ 109.2	$ 36.9	$ 52.4
Estimated grant date fair value of option vested \| $			$ 4.9	$ 7.8	$ 5.3
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)			1 year	1 year	1 year
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)			6 months	6 months	6 months
2006 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting term (in years)			3 years
2006 Plan \| First Anniversary of Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option exercisable rate (as a percent)			25.00%
2006 Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option, maximum period for grant			10 years
2006 Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of voting power			10.00%
2006 Plan \| ISO \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting term (in years)			5 years
2006 Plan \| Other Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting term (in years)			10 years
2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted during the period (in shares)		0
Shares available for future issuance (in shares)	3,865,000	3,865,000	8,693,162
Percentage of outstanding shares		5.00%
2016 Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option, maximum period for grant			10 years
2016 Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of common stock fair value on date of grant	100.00%	100.00%
Employee Stock Purchase Program ("ESPP")
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)	483,031	483,031	1,511,127
Percentage of outstanding shares		1.50%
Increase in shares available for future issuance (in shares)	966,062
Percentage of payroll deductions of eligible compensation	15.00%	15.00%
Offering period (in months)	12 months
Number of purchase period \| numberOfPurchasePeriod	2
Purchase period (in months)		6 months
Percentage of common stock fair market value available for employee purchase	85.00%
Common stock issued to employees (in shares)			420,352
Expected minimum volatility (as a percent)			68.72%	43.61%	41.46%
Expected maximum volatility (as a percent)			75.78%	48.05%	44.55%
Risk-free interest rate, minimum (as a percent)			0.11%	1.60%	2.19%
Risk-free interest rate, maximum (as a percent)			0.18%	2.35%	2.64%
Expected dividend yield			0.00%	0.00%	0.00%