Annual incentive compensation payable at the end of the period.

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Grant date.

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Long-term incentive compensation expense during the period relating to amortization of the grant date fair value of employee performance-based and service-based stock awards.

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Long-term incentive compensation expense during the period relating to amortization of the grant date fair value of employee performance-based restricted stock units.

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Share based compensation arrangement by share based payment award award vesting period.

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The period of time over which the employee needs to meet the performance objectives in order to qualify for the stock unit award in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Refers to an officer that has a targeted award opportunity percentage on their base salary.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of expense for salary, wage, profit sharing; incentive and equity-based compensation; and other employee benefit.

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Amount of selling, general and administrative expense classified as other.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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 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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COMPENSATION PROGRAMS - Additional Information (Details) - USD ($)	1 Months Ended				3 Months Ended		6 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Feb. 29, 2016	Jan. 31, 2016	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Short-term incentive compensation program accruals					$ 749,000		$ 749,000
Annual incentive compensation expense					1,560,000	$ 1,833,000	3,608,000	$ 2,948,000
Dividend equivalent rights payable					$ 13,232,000		$ 13,232,000		$ 18,487,000
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Targeted award opportunity on base salary							75.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Targeted award opportunity on base salary							125.00%
Long-Term Equity-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares available for future issuances (in shares)					3,369,164		3,369,164
Annual Incentive Compensation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual incentive compensation expense					$ 181,000		$ 749,000
Dividend Equivalent Rights Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual incentive compensation expense					84,000		180,000
Dividend Equivalent Rights Program [Member] \| Accounts Payable and Accrued Liabilities [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend equivalent rights payable					84,000		84,000
Performance-based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend equivalent rights payable					116,000		$ 116,000
Share awards performance period							3 years
Total original grants (in shares)	183,137	148,894	269,354
Grant date fair value per share (in dollars per share)	$ 8.71	$ 10.52	$ 8.03
Long term incentive compensation expense					14,000		$ 17,000
Service-Based Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total original grants (in shares)							41,797
Grant date fair value per share (in dollars per share)							$ 10.05
Grant date							Jul. 31, 2017
Service-based stock awards issuance period							1 year
Service-Based Stock Awards [Member] \| Management [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total original grants (in shares)	126,451	74,446	67,337
Grant date fair value per share (in dollars per share)	$ 8.60	$ 10.41	$ 9.32
Share-based compensation arrangement by share-based payment award vesting period	2021-01	2020-01	2019-02
Service-Based Stock Awards [Member] \| Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total original grants (in shares)	57,283	49,416		61,272
Grant date fair value per share (in dollars per share)	$ 8.60	$ 10.41		$ 7.87
Share-based compensation arrangement by share-based payment award vesting period	2021-01	2020-01		2019-01
Stock Awards Activity [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total original grants (in shares)							183,734
Grant date fair value per share (in dollars per share)							$ 8.60
Long term incentive compensation expense					308,000		$ 615,000
Other general and administrative expense					105,000		210,000
Total of unrecognized compensation expense for unvested stock award					$ 2,200,000		$ 2,200,000
Compensation cost not yet recognized, period for recognition							1 year 6 months