Share based compensation threshold consecutive trading period.

No definition available.

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- Definition

Share based compensation vesting stock price trigger to achieve vesting of performance based restricted stock units.

+ References

No definition available.

+ Details

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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.

+ 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=109197908&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-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
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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Period Type:	duration

- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

+ Details

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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

+ Details

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Period Type:	duration

- Definition

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

+ References

+ Details

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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

+ Details

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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.

+ Details

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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.

+ Details

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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 weighted average of per share prices paid for shares purchased on the open market for issuance to employees under 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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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

+ Details

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- Definition

Expected term of share-based compensation awards, 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
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Stock Plans and Stock-Based Compensation - Market-Based Restricted Stock Units - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 25,825,000	$ 9,299,000	$ 3,101,000
Dividend rate	0.00%
Market-Based Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, number of stock unit grants in period	57,500	392,000
Share Based compensation threshold consecutive trading days	30 days
Stock-based compensation expense	$ 10,500,000	$ 2,900,000
Risk-free interest rate, minimum	2.26%
Risk-free interest rate, maximum	2.90%
Dividend rate	0.00%
Expected term (in years)	10 years
Expected volatility, minimum	50.00%
Expected volatility, maximum	60.00%
Unrecognized compensation expense	$ 0
Vesting of restricted stock units	544,106	0
Vesting of restricted stock units, percentage	125.00%
Market-Based Restricted Stock Units \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, vesting stock price trigger	$ 35
Share-based compensation, share price on the date of issuance	33.06
Market-Based Restricted Stock Units \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, vesting stock price trigger	65
Share-based compensation, share price on the date of issuance	$ 45.17