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Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

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

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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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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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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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The weighted average fair value at grant date for nonvested equity-based awards issued 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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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares issued under share-based payment arrangement.

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STOCK-BASED COMPENSATION - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended			3 Months Ended	6 Months Ended
	Apr. 26, 2016	Apr. 07, 2016	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2018	Jun. 30, 2020	Jun. 30, 2020
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Cash dividend (in USD per share)	$ 1.30
Cash dividend	$ 28,886
Vested option stockholders
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Equivalent adjustments in the form of cash dividend equivalent payments (in USD per share)							$ 1.30
Equitable adjustments in the form of cash dividend equivalent payments							$ 5,396
Unvested option stockholders
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Equitable adjustments in the form of cash dividend equivalent payments							$ 1,235
Restricted stock awards
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Granted (in shares)							843,015
Granted (in USD per share)							$ 7.58
Unvested and outstanding (in shares)				579,283		1,022,599	1,022,599
Unrecognized compensation costs						$ 5,180	$ 5,180
Unrecognized compensation costs recognition period							1 year 5 months 23 days
Certain executives \| Restricted stock awards
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Granted (in shares)			280,953	51,500	95,000
Granted (in USD per share)			$ 7.58	$ 10.19	$ 22.33
Vesting period			2 years	3 years	3 years
Issued in period (in shares)			562,062
2016 Omnibus Incentive Plan
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Authorized additional stock options (in shares)		4,000,000
Stock options to purchase outstanding (in shares)						1,295,818	1,295,818
Transition Services Agreement \| Share-based Payment Arrangement, Option
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Additional stock compensation expense (credit) related to plan modification						$ (48)	$ 327