Deferred compensation arrangement with individual compensation expense not yet recognized period for recognisation.

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- Definition

Deferred compensation arrangement with individual unrecognized compensation expense not yet recognized.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award fair value assumptions expected forfeiture rate.

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- Definition

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for 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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- 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.

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- Definition

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

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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).

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- Definition

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

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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.

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No definition available.

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Equity-Based and Other Deferred Compensation - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense	$ 6.1	$ 2.1	$ 12.7	$ 5.9
Unrecognized compensation expense related to deferred cash awards	48.4		$ 48.4
Weighted-average period over compensation cost is expected to be recognized			2 years 7 months 6 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated unrecognized compensation expense related to unvested awards	126.1		$ 126.1
Weighted-average period for recognition of compensation expense related to unvested awards			1 year 4 months 24 days
Granted			1,955,929
Vested			1,795,850
Forfeited			62,541
RSU Awards Containing Service and Market Conditions
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted			12,658
Forfeited			15,968
RSU Awards Containing Service and Market Conditions \| CamberView
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated unrecognized compensation expense related to unvested awards	4.5		$ 4.5
Weighted-average period for recognition of compensation expense related to unvested awards			2 years 8 months 12 days
Restricted Share Awards \| CamberView \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated unrecognized compensation expense related to unvested awards	0.3		$ 0.3
Weighted-average period for recognition of compensation expense related to unvested awards			2 years 3 months 18 days
Vesting period			4 years
Granted			3,591		5,100
Vested			0
Forfeited			0
Partnership Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated unrecognized compensation expense related to unvested awards	24.0		$ 24.0
Assumed forfeiture rate			4.00%
Weighted-average period for recognition of compensation expense related to unvested awards			6 months
Granted			78,278
Vested			156,354
Partnership Unit Awards Containing Service and Market Conditions
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated unrecognized compensation expense related to unvested awards	$ 2.0		$ 2.0
Assumed forfeiture rate			4.00%
Weighted-average period for recognition of compensation expense related to unvested awards			3 months 18 days
Vested			122,902
Forfeited			3,798
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			1 year
Minimum \| Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Assumed forfeiture rate			1.00%
Minimum \| RSU Awards Containing Service and Market Conditions \| CamberView
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Assumed forfeiture rate			4.00%
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			4 years
Maximum \| Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Assumed forfeiture rate			9.00%
Maximum \| RSU Awards Containing Service and Market Conditions \| CamberView
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Assumed forfeiture rate			9.00%