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This is the percentage of an employee's salary and bonus that the company will match regardless of employee participation in the plan.

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

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

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The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

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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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The aggregate amount of expenditures for salaries, wages, profit sharing and incentive compensation, and other employee benefits, including equity-based compensation, and pension and other postretirement benefit expense.

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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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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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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COMPENSATION PROGRAMS - Additional Information (Details) - USD ($)	1 Months Ended						12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Mar. 31, 2016	Feb. 29, 2016	Jan. 31, 2016	Jan. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Short-term incentive compensation program accruals							$ 894,000
Adjustment of short-term incentive compensation program accruals							938,000
Annual incentive compensation expense							4,915,000	$ 11,749,000	$ 10,200,000
Dividend equivalent rights payable							$ 18,487,000	22,634,000
Defined Contribution Plan Disclosure [Abstract]
Defined contribution plan, voluntary contribution based on compensation							50.00%
Defined contribution plan, employer matching contribution							3.00%
Defined contribution plan, cost recognized							$ 180,000	385,000	391,000
Nonqualified Deferred Compensation Plan [Member]
Defined Contribution Plan Disclosure [Abstract]
Accrued deferred compensation plan balances payable to participating executives							$ 7,400,000
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%
Defined Contribution Plan Disclosure [Abstract]
Defined contribution plan, annual contributions per employee							6.00%
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)							3,684,662
Annual Incentive Compensation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual incentive compensation expense			$ 3,600,000						3,400,000
Dividend Equivalent Rights Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual incentive compensation expense							$ 434,000	621,000	746,000
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							114,000
Performance-based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend equivalent rights payable							$ 193,000	235,000
Share awards performance period							3 years
Total original grants (in shares)		148,894		269,354		247,512	148,894
Grant date fair value per share (in dollars per share)		$ 10.52		$ 8.03		$ 8.83	$ 10.52
Forfeitures (in shares)							(398,623)
Long term incentive compensation expense							$ 149,000	204,000	818,000
Performance-based RSUs [Member] \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total original grants (in shares)	183,137
Grant date fair value per share (in dollars per share)	$ 8.71
Performance-based RSUs [Member] \| December 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeitures (in shares)							(117,255)
Service-Based Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total original grants (in shares)		41,881					41,797
Grant date fair value per share (in dollars per share)		$ 10.03					$ 10.05
Grant date		Jul. 31, 2017					Jul. 31, 2016
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					37,237
Grant date fair value per share (in dollars per share)	$ 8.60	$ 10.41			$ 7.87					$ 12.47
Share-based compensation arrangement by share-based payment award vesting period	2021-01	2020-01			2019-01					2018-01
Stock Awards Activity [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend equivalent rights payable							$ 134,000	350,000
Total original grants (in shares)							165,659
Grant date fair value per share (in dollars per share)							$ 10.32
Forfeitures (in shares)							(34,565)
Long term incentive compensation expense							$ 834,000	828,000	878,000
Other general and administrative expense							421,000	$ 409,000	$ 436,000
Total of unrecognized compensation expense for unvested stock award							$ 1,400,000
Compensation cost not yet recognized, period for recognition							1 year 4 months 24 days
Stock Awards Activity [Member] \| Vested 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total original grants (in shares)							62,137
Grant date fair value per share (in dollars per share)							$ 11.67
Stock Awards Activity [Member] \| Vested 2016 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total original grants (in shares)								118,784
Grant date fair value per share (in dollars per share)								$ 12.17
Stock Awards Activity [Member] \| Vested 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total original grants (in shares)									125,221
Grant date fair value per share (in dollars per share)									$ 12.58
Stock Awards Activity [Member] \| Vested 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total original grants (in shares)										114,423
Grant date fair value per share (in dollars per share)										$ 13.31
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable option awards outstanding (in shares)							30,000
Weighted average strike price (in dollars per share)							$ 12.28
Aggregate intrinsic value							$ 0
Exercisable, weighted average remaining contractual term							1 year 1 month 6 days
Option awards expired (in shares)							10,000
Weighted average strike price of options expired (in dollars per share)							$ 10.58
Exercisable, intrinsic value							$ 0
Share awards contractual term							10 years