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

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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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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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No definition available.

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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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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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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 (Details) (USD $)	0 Months Ended	12 Months Ended
STOCKHOLDERS' EQUITY (Details) (USD $)	Sep. 14, 2010	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
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, including the 200,000 Units, is as follows:
Share based compensation charged to operations		1,833,000	1,440,000	1,223,000
Compensation costs related to non-vested awards that have not yet been recognized		4,856,000
Approximate weighted average vesting period		2 years 4 months 24 days
Restricted stock grants
Stock Based Compensation
Vesting period		5 years
Summary of the activity of the incentive plans
Restricted share grants		118,850	112,650	109,450
Average per share grant price (in dollars per share)		20.54	21.59	16.77
Deferred compensation to be recognized over vesting period		2,441,000	2,432,000	1,835,000
Non-vested shares:
Non-vested beginning of period (in shares)		470,015	407,460	348,385
Grants (in shares)		118,850	112,650	109,450
Vested during period (in shares)		(101,300)	(50,095)	(49,325)
Forfeitures (in shares)		(6,570)		(1,050)
Non-vested end of period (in shares)		480,995	470,015	407,460
Other disclosures
Average per share value of non-vested shares (based on grant price) (in dollars per share)		14.55	14.22	12.59
Value of shares vested during the period (based on grant price)		621,000	876,000	1,208,000
Average value of shares forfeited (based on grant price) (in dollars per share)		15.49		13.65
The total charge to operations for all incentive plans, including the 200,000 Units, is as follows:
Share based compensation charged to operations		1,701,000	1,341,000	1,050,000
Restricted stock units
The total charge to operations for all incentive plans, including the 200,000 Units, is as follows:
Share based compensation charged to operations		132,000	99,000	173,000
2012 Incentive Plan
Stock Based Compensation
Number of shares authorized for issuance		600,000
Shares issued pursuant to plan		228,950
Prior Incentive Plans
Non-vested shares:
Non-vested end of period (in shares)		452,000
Pay-for-performance program
The total charge to operations for all incentive plans, including the 200,000 Units, is as follows:
Compensation costs related to non-vested awards that have not yet been recognized		297,000
Pay-for-performance program \| Restricted stock units
Stock Based Compensation
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 share grants	200,000
Average per share grant price (in dollars per share)	$ 11.74
Deferred compensation to be recognized over vesting period	$ 808,000
Non-vested shares:
Grants (in shares)	200,000
Vested during period (in shares)		0	0	0
Forfeitures (in shares)		0	0	0