EQUITY-BASED COMPENSATION (Narrative) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
EQUITY-BASED COMPENSATION [Abstract]
Estimated forfeiture rate	3.00%
Weighted average fair value of restricted shares per share granted	$ 10.92	$ 9.08
Aggregate fair value of stock vested	$ 3,500	$ 2,800
Shares issued relating to vesting of restricted stock awards, shares	221,269	637,686
Value of unvested restricted stock	$ 15,400
Weighted-average recognition period for unvested restricted stock	2 years 4 months 21 days
Shares issued upon excercise of options			109,167

ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsEstimatedForfeitureRate

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- Definition

The aggregate fair value of nonvested restricted stock awards for which the employer is contingently obligated to issue restricted stock 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.

+ References

No definition available.

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 718

-SubTopic 10

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

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- Definition

Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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- Definition

Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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Number of share options (or share units) exercised during the current period.

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