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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Installment Number

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- Definition

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, shown as a percentage of the original share amount.

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- Definition

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

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- Definition

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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- 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 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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- Definition

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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- Definition

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

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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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.

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- Definition

Gross number of share options (or share units) granted during the period.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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- Definition

Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Number of non-vested options outstanding.

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- Definition

Value, before forfeiture, of shares granted under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

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- Definition

Number of share options (or share units) exercised during the current period.

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STOCK-BASED COMPENSATION - Narrative (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	Sep. 11, 2017 USD ($) installment shares	Dec. 31, 2019 USD ($) plan $ / shares shares	Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award
Number of stock-based employee compensation plans \| plan		3
Non-cash stock-based compensation expense \| $		$ 4,600	$ 6,800	$ 8,400
Total unrecognized compensation cost related to non-vested stock awards \| $		$ 9,900
Weighted average period over which compensation cost related to non-vested stock awards is recognized		1 year 4 months 24 days
Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period		4 years
Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares available for grant (in shares)		4,500,000	2,200,000
Time-based stock options
Share-based Compensation Arrangement by Share-based Payment Award
Exercised (in shares)		0	0	0
Granted (in shares)		0
Options, weighted average grant date fair value (in dollars per share) \| $ / shares				$ 3.50
Time-based stock options \| Year 1
Share-based Compensation Arrangement by Share-based Payment Award
Annual vesting percentage		25.00%
Time-based stock options \| Year 2
Share-based Compensation Arrangement by Share-based Payment Award
Annual vesting percentage		25.00%
Time-based stock options \| Year 3
Share-based Compensation Arrangement by Share-based Payment Award
Annual vesting percentage		25.00%
Time-based stock options \| Year 4
Share-based Compensation Arrangement by Share-based Payment Award
Annual vesting percentage		25.00%
Time-based restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock awards outstanding (in shares)		1,040,431	817,696
Intrinsic value of stock based awards other than options \| $		$ 2,800
Time-based restricted stock awards \| Year 1
Share-based Compensation Arrangement by Share-based Payment Award
Annual vesting percentage		33.33%
Time-based restricted stock awards \| Year 2
Share-based Compensation Arrangement by Share-based Payment Award
Annual vesting percentage		33.33%
Time-based restricted stock awards \| Year 3
Share-based Compensation Arrangement by Share-based Payment Award
Annual vesting percentage		33.33%
Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock awards outstanding (in shares)		954,937	277,817
Vesting period		3 years
Intrinsic value of stock based awards other than options \| $		$ 2,600
Performance-based restricted stock awards with a market condition
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock awards outstanding (in shares)		0	199,028
Vesting period		3 years
Peer group volatility				34.60%
Risk-free rate				1.46%
Performance-based restricted stock awards with a market condition \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting rights percentage		0.00%
Performance-based restricted stock awards with a market condition \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting rights percentage		200.00%
Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award
Non-cash stock-based compensation expense \| $		$ 1,500
Chief Executive Officer \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Make-whole restricted stock awards \| $	$ 600
Make-whole restricted stock awards, vested in period (in shares)	67,000
Chief Executive Officer \| Restricted Stock \| Year 1
Share-based Compensation Arrangement by Share-based Payment Award
Make-whole restricted stock awards \| $	$ 950
Restricted stock awards outstanding (in shares)	106,000
Chief Executive Officer \| Restricted Stock \| Year 2
Share-based Compensation Arrangement by Share-based Payment Award
Make-whole restricted stock awards \| $	$ 1,200
Restricted stock awards outstanding (in shares)	134,000
Award vesting installment number \| installment	3
Chief Executive Officer \| Restricted Stock \| Year 3
Share-based Compensation Arrangement by Share-based Payment Award
Make-whole restricted stock awards \| $	$ 1,900
Restricted stock awards outstanding (in shares)	212,000
Award vesting installment number \| installment	3
Chief Executive Officer \| Time-based stock options \| Year 3
Share-based Compensation Arrangement by Share-based Payment Award
Stock options, nonvested outstanding (in shares)	519,000
2018 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares authorized for issuance (in shares)		20,200,000
Number of shares available for grant (in shares)		6,600,000	11,100,000
2018 Stock Plan \| Time-based restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award
Make-whole restricted stock awards, vested in period (in shares)		491,530
Restricted stock awards outstanding (in shares)		1,040,431	817,696
Vesting period		3 years
Intrinsic value of stock based awards other than options \| $		$ 1,000	$ 1,300	$ 3,000
Weighted average grant date fair value (in dollars per share) \| $ / shares		$ 1.62		$ 10.01
2018 Stock Plan \| Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award
Make-whole restricted stock awards, vested in period (in shares)		0
Restricted stock awards outstanding (in shares)		954,937	277,817
Weighted average grant date fair value (in dollars per share) \| $ / shares		$ 2.76		$ 15.42
2018 Stock Plan \| Performance-based restricted stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting rights percentage		0.00%
2018 Stock Plan \| Performance-based restricted stock units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting rights percentage		150.00%
2018 Stock Plan \| Performance-based restricted stock awards with a market condition
Share-based Compensation Arrangement by Share-based Payment Award
Make-whole restricted stock awards, vested in period (in shares)		0
Restricted stock awards outstanding (in shares)		0	199,028
Weighted average grant date fair value (in dollars per share) \| $ / shares		$ 0