Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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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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The percentage of payout of stock on targeted achievement.

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The number of trading days preceding the vesting date to calculate the volume weighted average closing price of a share.

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The percentage of targeted amount earned.

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The target amount of stock-settled incentive awards granted during the period.

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EQUITY-BASED COMPENSATION - Stock-Settled Incentive Awards (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended		16 Months Ended
	May 17, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019
EQUITY-BASED COMPENSATION
offering period				3 years
Stock-Settled Incentive Awards
EQUITY-BASED COMPENSATION
offering period	2 years
Vesting date						30 days
Target amount of stock settled incentive awards granted						$ 3.9
Compensation expense		$ 0.1	$ 0.1	$ 0.4	$ 0.2
Unrecognized compensation expense		$ 0.4		$ 0.4		$ 0.4
Stock-Settled Incentive Awards \| Minimum
EQUITY-BASED COMPENSATION
Pay out percentage	0.00%
Stock-Settled Incentive Awards \| Maximum
EQUITY-BASED COMPENSATION
Pay out percentage	200.00%
Stock-Settled Incentive Awards \| Less than $20.00
EQUITY-BASED COMPENSATION
Percentage of Target Amount Earned						0.00%
Stock-Settled Incentive Awards \| At least $20.00, but less than $25.00
EQUITY-BASED COMPENSATION
Percentage of Target Amount Earned						100.00%
Stock-Settled Incentive Awards \| $25.00 or greater
EQUITY-BASED COMPENSATION
Percentage of Target Amount Earned						200.00%