Adjustment of annual incentive compensation program accruals.

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Annual incentive compensation payable at the end of the period.

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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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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 date.

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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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Amount of cost for defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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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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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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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 equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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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No definition available.

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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 outstanding, including both vested and non-vested options.

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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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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						3 Months Ended			9 Months Ended		12 Months Ended
	Jan. 31, 2017	Jul. 31, 2016	Feb. 29, 2016	Jan. 31, 2016	Jan. 31, 2015	Dec. 31, 2013	Sep. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Short-term incentive compensation program accruals							$ 694,000			$ 694,000
Annual incentive compensation expense							1,073,000		$ 4,039,000	4,021,000	$ 9,305,000
Adjustment of short-term incentive compensation program accruals								$ 938,000
Dividend equivalent rights payable							18,688,000			$ 18,688,000					$ 22,634,000
Total original grants (in shares)										165,659
Grant date fair value per share (in dollars per share)										$ 10.32
Forfeitures (in shares)										(24,881)
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							$ 31,000			$ 119,000
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			3,684,662
2017 Annual Incentive Compensation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual incentive compensation expense							$ (124,000)			$ 694,000
Dividend Equivalent Rights Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual incentive compensation expense							100,000			320,000
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							100,000			100,000
Performance-based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend equivalent rights payable							339,000			$ 339,000
Share awards performance period										3 years
Total original grants (in shares)	148,894		269,354		247,512	242,505
Grant date fair value per share (in dollars per share)	$ 10.52		$ 8.03		$ 8.83	$ 12.45
Long term incentive compensation expense							73,000			$ 696,000
Performance-based RSUs [Member] \| December 2016 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeitures (in shares)										(99,257)
Performance-based RSUs [Member] \| December 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeitures (in shares)										(93,058)		(37,199)
Performance-based RSUs [Member] \| December 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeitures (in shares)												(36,467)
Stock Awards Activity [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Long term incentive compensation expense							220,000			$ 660,000
Other general and administrative expense							106,000			316,000
Total of unrecognized compensation expense for unvested stock award							1,800,000			$ 1,800,000
Compensation cost not yet recognized, period for recognition										1 year 4 months 25 days
Stock Awards Activity [Member] \| January 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
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
Forfeitures (in shares)		(24,881)
Service-based stock awards issuance period										1 year
Grant date	Jul. 15, 2017									Jul. 31, 2016
Service-Based Stock Awards [Member] \| Management [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend equivalent rights payable							$ 114,000			$ 114,000
Total original grants (in shares)	74,446		67,337
Grant date fair value per share (in dollars per share)	$ 10.41		$ 9.32
Service-based stock awards issuance period										3 years
Share-based compensation arrangement by share-based payment award vesting period	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)	49,416			61,272									37,237	35,703
Grant date fair value per share (in dollars per share)	$ 10.41			$ 7.87									$ 12.47
Service-based stock awards issuance period										3 years
Share-based compensation arrangement by share-based payment award vesting period	2020-01			2019-01									2018-01
Share-based compensation arrangement by share-based payment award vesting date														Jan. 03, 2017
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable option awards outstanding (in shares)							30,000			30,000
Weighted average strike price (in dollars per share)							$ 12.28			$ 12.28
Aggregate intrinsic value							$ 0			$ 0
Exercisable, weighted average remaining contractual term										1 year 3 months 19 days
Exercisable, intrinsic value							$ 0			$ 0
Share awards contractual term										10 years