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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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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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-Paragraph 2

-Subparagraph (c)(1)(iv)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

STOCK COMPENSATION PLANS (Details) (USD $)	3 Months Ended		6 Months Ended
STOCK COMPENSATION PLANS (Details) (USD $)	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	May 25, 2005
Non-vested shares of Class A Stock under option [Abstract]
Vesting period for granted option (in years)			1 year
Options granted term (in years)			10 years
Weighted-average assumptions used for grants issued [Abstract]
Expected Dividend Yield (in hundredths)			4.18%	3.99%
Expected Stock Price Volatility (in hundredths)			25.13%	24.97%
Weighted Average Risk-Free Interest Rate (in hundredths)			1.87%	3.12%
Weighted Average Expected Life of Options (in years)			9 years 5 months 6 days	8 years 4 months 3 days
Base period for calculation of expected dividend yield (in months)			12 months
Period for risk free interest rate base on treasury constant maturity rate (in years)			10 years
Total intrinsic value of options exercised			$ 166,400
Unrecognized expense related to non-vested option shares	84,000		84,000
Period over which unvested options cost will recognized (in years)			10 months 3 days
Class A Stock [Member] \| 2005 Equity Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorizes for new issues					500,000
Compensation expense	29,000	31,000	58,000	62,000
Class A Stock [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at beginning of period, option shares (in shares)			450,000
Granted, option shares (in shares)			33,750
Exercised, option shares (in shares)			27,000
Expired, option shares (in shares)			0
Outstanding at end of period, option shares (in shares)	456,750		456,750
Shares of Class A Non-Voting Common Stock under option [Abstract]
Outstanding at beginning of period, weighted average exercise price (in dollars per shares)			$ 17.61
Granted, weighted average exercise price (in dollars per shares)			$ 19.01
Exercised, weighted average exercise price (in dollars per shares)			$ 13.01
Outstanding at end of period, weighted average exercise price (in dollars per shares)	$ 17.98		$ 17.98
Options exercisable at end of period, weighted average exercise price (in dollars per shares)	$ 17.90		$ 17.90
Outstanding at end of period, weighted average remaining life (in years)			4 years 8 months
Options exercisable at end of period, weighted average remaining life (in years)			4 years 3 months 1 day
Outstanding at end of period, aggregate intrinsic value	1,625,000		1,625,000
Options exercisable at end of period, aggregate intrinsic value	$ 1,540,000		$ 1,540,000
Options exercisable at end of period, option share (in shares)	423,000		423,000
Share Based Compensation Arrangement By Share Based Payment Award Nonvested Options Outstanding [Roll Forward]
Granted, option shares (in shares)			33,750
Class A Stock [Member] \| Non-Vested Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Granted, option shares (in shares)			33,750
Share Based Compensation Arrangement By Share Based Payment Award Nonvested Options Outstanding [Roll Forward]
Outstanding at beginning of period, Non-vested option shares (in shares)			33,750
Granted, option shares (in shares)			33,750
Vested, option shares (in shares)			(33,750)
Canceled, option shares (in shares)			0
Outstanding at end of period, Non-vested option shares (in shares)	33,750		33,750
Non-vested shares of Class A Stock under option [Abstract]
Outstanding at beginning of period, weighted average grant - date fair value per option (in dollars per shares)			$ 3.50
Granted, weighted average grant - date fair value per option (in dollars per shares)			$ 2.92
Vested, weighted average grant - date fair value per option (in dollars per shares)			$ 3.50
Canceled, weighted average grant - date fair value per option (in dollars per shares)			$ 0
Outstanding at end of period, weighted average grant - date fair value per option (in dollars per shares)	$ 2.92		$ 2.92