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

No definition available.

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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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No definition available.

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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.

+ References

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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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- 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.

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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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- Definition

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

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No definition available.

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- Definition

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

+ References

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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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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No definition available.

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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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- Definition

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

+ References

No definition available.

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

+ References

No definition available.

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- Definition

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

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No definition available.

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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) - Stock options $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($) $ / shares shares	Sep. 30, 2017 shares	Sep. 30, 2018 USD ($) $ / shares shares	Sep. 30, 2017 shares	Dec. 31, 2017 USD ($) $ / shares shares
Schedule of stock option activity and other stock option information
Beginning Balance, Number of shares \| shares			100,000
Awards assumed through acquisition of CEC, Number of shares \| shares			319,846
Grants, Number of shares \| shares
Exercise of stock options, net (in shares) \| shares		0	(138,186)	0
Forfeitures/Expirations, Number of shares \| shares
Ending Balance, Number of shares \| shares	281,660		281,660		100,000
Exercisable, Number of shares \| shares	122,133		122,133
Beginning Balance, Weighted-average exercise price \| $ / shares			$ 51.95
Awards assumed through acquisition of CEC, Weighted-average exercise price \| $ / shares			66.98
Grants, Weighted-average exercise price \| $ / shares
Exercises, Weighted-average exercise price \| $ / shares			55.32
Forfeitures/Expirations, Weighted-average exercise price \| $ / shares
Ending Balance, Weighted-average exercise price \| $ / shares	$ 67.36		67.36		$ 51.95
Exercisable, Weighted-average exercise price \| $ / shares	$ 65.94		$ 65.94
Weighted-average remaining contractual life (years)			7 years 1 month 6 days		3 years 1 month 6 days
Exercisable, Weighted-average remaining contractual life (years)			6 years 3 months 18 days
Beginning Balance, Aggregate intrinsic value \| $			$ 3,763
Ending Balance, Aggregate intrinsic value \| $	$ 19,623		19,623		$ 3,763
Exercisable, Aggregate intrinsic value \| $	8,683		8,683
Aggregate intrinsic value of stock options exercised \| $	$ 9,700		$ 9,700