The number of equity based awards assumed through an acquisition during the reporting period.

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Weighted average of fair value as of the grant date of equity based award options that were assumed through an acquisition in the reporting period.

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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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.

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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No definition available.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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Equity Awards - Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Schedule of stock option activity and other stock option information
Grants (in shares)	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Grants, Weighted-average exercise price (in dollars share)	$ 0	$ 0	$ 0
Additional information regarding share-based payment arrangements
Net cash proceeds related to stock options exercised	$ (1,800)	$ 8,600
Aggregate intrinsic value of stock options exercised	$ 17,400	$ 11,300
Stock options
Schedule of stock option activity and other stock option information
Beginning Balance (in shares)	256,246	100,000	100,000
Awards assumed through acquisition of CEC (in shares)		319,846
Exercise of stock options, net (in shares)	(208,114)	(162,831)	0
Forfeitures/Expirations (in shares)	(2,036)	(769)	0
Ending Balance (in shares)	46,096	256,246	100,000	100,000
Exercisable (in shares)	24,246
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Beginning Balance, Weighted-average exercise price (in dollars share)	$ 66.80	$ 51.95	$ 51.95
Awards assumed through acquisition of CEC, Weighted-average exercise price (in dollars share)		66.98
Exercises, Weighted-average exercise price (in dollars share)	67.61	$ 58.11	0
Forfeitures/Expirations, Weighted-average exercise price (in dollars share)	58.38	51.96	0
Ending Balance, Weighted-average exercise price (in dollars share)	$ 63.49	$ 66.80	$ 51.95	$ 51.95
Exercisable, Weighted-average exercise price (in dollars share)					$ 60.27
Weighted-average remaining contractual life (years)	5 years 2 months 12 days	7 years	3 years 1 month 6 days	4 years 1 month 6 days
Exercisable, Weighted-average remaining contractual life (years)	4 years
Aggregate intrinsic value					$ 4,398	$ 11,947	$ 3,763	$ 2,868
Exercisable, Aggregate intrinsic value					$ 2,391
Additional information regarding share-based payment arrangements
Stock options outstanding	46,096	256,246	100,000	100,000	46,096	256,246	100,000	100,000