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

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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

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- Definition

Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

+ References

No definition available.

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- Definition

Intrinsic value of equity-based compensation awards vested. Excludes stock and unit options.

+ References

No definition available.

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- Definition

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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- Definition

Weighted average remaining vesting term for expected to vest equity-based payment instruments, excluding stock (or unit) options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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Equity-Based Compensation - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019
Stock options
Equity based compensation
Aggregate intrinsic value of stock options exercised	$ 4.3	$ 4.8
Aggregate intrinsic value of stock options outstanding	6.9
Aggregate intrinsic value of stock options exercisable	6.9
Restricted stock
Equity based compensation
Intrinsic value of stock vested and repurchased (less than $0.1 million)	1.8	1.6
Aggregate intrinsic value of nonvested restricted common stock	$ 1.8
Weighted average remaining vesting term for options expected to vest	1 year
Restricted stock \| Maximum
Equity based compensation
Unrecognized share-based compensation	$ 1.8
Restricted stock units
Equity based compensation
Aggregate intrinsic value of nonvested restricted common stock	718.0
Unrecognized share-based compensation	$ 531.5
Weighted average remaining vesting term for options expected to vest	1 year 7 months 4 days
Intrinsic value, of stock vested	$ 262.4	$ 137.2
2014 Plan
Equity based compensation
Number of shares authorized	8,603,066
2014 Plan \| Subsequent Event
Equity based compensation
Number of shares available for future grant			6,202,378