Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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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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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).

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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.

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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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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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Stock-Based Compensation - (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	May 17, 2019
STOCK BASED COMPENSATION
Options outstanding and exercisable (in share)	662,322		662,322
Weighted average exercise price of options exercisable (in dollars per share)	$ 12.77		$ 12.77
Average remaining contractual term of options exercisable			7 years 7 months 6 days
Stock-based compensation expense	$ 3.4	$ 3.7	$ 10.1	$ 9.6
2019 Omnibus Incentive Plan
STOCK BASED COMPENSATION
Shares of common stock authorized for issuance under the share-based compensation plan					2,025,000
2016 Omnibus Incentive Plan
STOCK BASED COMPENSATION
Available for issuance (in shares)					243,611
Performance-based stock awards
STOCK BASED COMPENSATION
Shares outstanding	647,519		647,519
Weighted average grant date fair value	$ 17.90		$ 17.90
Nonvested restricted stock awards
STOCK BASED COMPENSATION
Shares outstanding	1,904,747		1,904,747
Employee Service Based Awards
STOCK BASED COMPENSATION
Shares outstanding	1,201,476		1,201,476
Weighted average grant date fair value	$ 15.77		$ 15.77
Director Service Based Awards
STOCK BASED COMPENSATION
Shares outstanding	55,752		55,752
Weighted average grant date fair value	$ 20.10		$ 20.10