Represents the aggregate number of share instruments vested under a share-based compensation plan since inception.

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The value of shares granted 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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Represents the number of shares to be vested and issued for each unit outstanding upon non satisfaction of the performance criteria.

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Represents the approximate weighted average vesting period for equity awards granted under the equity-based compensation arrangement.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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No definition available.

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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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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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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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 maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Number of options outstanding, including both vested and non-vested options.

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Number of share instruments newly issued under a share-based compensation plan.

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STOCKHOLDERS' EQUITY - Stock Based Compensation (Details) - USD ($)			12 Months Ended
	Jan. 09, 2017	Sep. 14, 2010	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stock Based Compensation
Outstanding options at the end of the period (in shares)			0	0	0
The total charge to operations for all incentive plans is as follows:
Share based compensation charged to operations			$ 2,983,000	$ 2,334,000	$ 1,833,000
Compensation costs related to non-vested awards that have not yet been recognized			$ 5,960,000
Approximate weighted average vesting period			1 year 8 months 12 days
Restricted stock grants
Stock Based Compensation
Restricted stock grants			139,225	129,975	118,850
Vesting period			5 years
Summary of the activity of the incentive plans
Restricted stock grants			139,225	129,975	118,850
Per share grant price (in dollars per share)			$ 21.74	$ 24.60	$ 20.54
Deferred compensation to be recognized over vesting period			$ 3,027,000	$ 3,197,000	$ 2,441,000
Number of non-vested shares:
Non-vested beginning of year (in shares)			538,755	480,995	470,015
Grants (in shares)			139,225	129,975	118,850
Vested during year (in shares)			(85,730)	(72,215)	(101,300)
Forfeitures (in shares)			(500)		(6,570)
Non-vested end of year (in shares)			591,750	538,755	480,995
The following information includes the 200,000 Units:
Average per share value of non-vested shares (based on grant price) (in dollars per share)			$ 17.95	$ 17.12	$ 14.55
Value of stock vested during the year (based on grant price)			$ 1,451,500	$ 612,000	$ 621,000
Average value of shares forfeited during the period (based on grant price) (in dollars per share)			$ 21.05		$ 15.49
The total charge to operations for all incentive plans is as follows:
Share based compensation charged to operations			$ 2,692,000	2,204,000	$ 1,701,000
Restricted stock units
The total charge to operations for all incentive plans is as follows:
Share based compensation charged to operations			$ 291,000	$ 130,000	$ 132,000
2016 Incentive Plan
Stock Based Compensation
Number of shares authorized for issuance			750,000
Shares issued pursuant to plan			0
Restricted stock grants	140,100
Aggregate value of restricted shares granted	$ 3,467,000
Summary of the activity of the incentive plans
Restricted stock grants	140,100
Number of non-vested shares:
Grants (in shares)	140,100
2012 and 2009 Incentive Plan
Stock Based Compensation
Restricted stock grants			0
Summary of the activity of the incentive plans
Restricted stock grants			0
Number of non-vested shares:
Grants (in shares)			0
Vested during year (in shares)			0
Non-vested end of year (in shares)			791,750
Pay-for-performance program
The total charge to operations for all incentive plans is as follows:
Compensation costs related to non-vested awards that have not yet been recognized			$ 74,000
Pay-for-performance program \| Restricted stock units
Stock Based Compensation
Restricted stock grants		200,000
Vesting period		7 years
Number of share instruments vested since plan's inception			1
Number of shares to be issued for each unit outstanding on not satisfying performance criteria at June 30, 2017			0
Summary of the activity of the incentive plans
Restricted stock grants		200,000
Per share grant price (in dollars per share)		$ 11.74
Deferred compensation to be recognized over vesting period		$ 1,005,000
Number of non-vested shares:
Grants (in shares)		200,000
Vested during year (in shares)			0	0	0
Forfeitures (in shares)			0	0	0