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Tax benefits realized from the exercise of stock options in prior years resulting in reductions in the entity's income taxes, which increases net cash provided by operating activities.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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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 cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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

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Net number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including 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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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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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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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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STOCK COMPENSATION PLANS (Details) (USD $)	12 Months Ended
STOCK COMPENSATION PLANS (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	May 25, 2005
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorizes under the plan (in shares)				500,000
Number of directors consists in committee	3
Weighted Average Exercise [Abstract]
Fair value of options granted (in dollars per shares)	$ 2.92	$ 3.50	$ 3.73
Total intrinsic value of options exercised	$ 449,000	$ 167,000	$ 700,000
Received cash from the exercise of options	852,000
Tax Benefit from Stock Options Exercised in Prior Years	291,000
Tax benefit realized during the period	177,000
Options Exercisable [Abstract]
Unrecognized expense related to non-vested option shares	35,000
Period over which unvested options cost will recognized	4 months 24 days
1992 Non-Qualified Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorizes under the plan (in shares)	375,000
Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair market value stock options are priced (in hundredths)	85.00%
Directors and Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair market value stock options are priced (in hundredths)	90.00%
Employee and director [Member] \| $13.30 - $18.44 [Member]
Options Outstanding [Abstract]
Range of Exercise Price, Minimum (in dollars per shares)	$ 13.30
Range of Exercise Price, Maximum (in dollars per shares)	$ 18.44
Shares Outstanding (in shares)	153,750
Weighted Average Remaining Life	3 years 2 months 26 days
Weighted Average Exercise Price (in dollars per shares)	$ 16.17
Aggregate Intrinsic Value	963,000
Options Exercisable [Abstract]
Range of Exercise Price, Minimum (in dollars per shares)	$ 13.30
Range of Exercise Price, Maximum (in dollars per shares)	$ 18.44
Shares Exercisable (in shares)	153,750
Weighted Average Remaining Life	3 years 2 months 26 days
Weighted Average Exercise Price (in dollars per shares)	$ 16.17
Aggregate Intrinsic Value	963,000
Employee and director [Member] \| $18.45 - $21.12 [Member]
Options Outstanding [Abstract]
Range of Exercise Price, Minimum (in dollars per shares)	$ 18.45
Range of Exercise Price, Maximum (in dollars per shares)	$ 21.12
Shares Outstanding (in shares)	267,750
Weighted Average Remaining Life	5 years 2 months 8 days
Weighted Average Exercise Price (in dollars per shares)	$ 19.52
Aggregate Intrinsic Value	778,000
Options Exercisable [Abstract]
Range of Exercise Price, Minimum (in dollars per shares)	$ 18.45
Range of Exercise Price, Maximum (in dollars per shares)	$ 21.12
Shares Exercisable (in shares)	234,000
Weighted Average Remaining Life	4 years 11 months 16 days
Weighted Average Exercise Price (in dollars per shares)	$ 19.6
Aggregate Intrinsic Value	$ 663,000
Class A Stock [Member] \| Key Employees and Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorizes under the plan (in shares)	150,000
Class A Stock [Member] \| Stock Options [Member]
Shares [Abstract]
Outstanding at beginning of year (in shares)	450,000	440,800	497,889
Granted (in shares)	33,750	33,750	33,750
Exercised (in shares)	(62,250)	(24,550)	(90,839)
Expired (in shares)	0	0	0
Outstanding at end of year (in shares)	421,500	450,000	440,800
Options exercisable at year end (in shares)	387,750	416,250	407,050
Weighted Average Exercise [Abstract]
Outstanding at beginning of year (in dollars per shares)	$ 17.61	$ 17.18	$ 15.91
Granted (in dollars per shares)	$ 19.01	$ 19.06	$ 18.61
Exercised (in dollars per shares)	$ 13.68	$ 11.87	$ 10.75
Expired (in dollars per shares)	$ 0	$ 0	$ 0
Outstanding at end of year (in dollars per shares)	$ 18.30	$ 17.61	$ 17.18
Options exercisable at year end (in dollars per shares)	$ 18.24	$ 17.49	$ 17.06