NET INCOME PER COMMON SHARE AND EQUITY PER COMMON SHARE (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Shares used in computing basic and diluted net income per share [Abstract]
Weighted average common shares outstanding during the period for Basic computation (in shares)	8,884,000	8,774,000	8,666,000
Dilutive effect of employee stock options (in shares)	42,000	62,000	51,000
Weighted average common shares outstanding during the period for Diluted computation (in shares)	8,926,000	8,836,000	8,717,000
Common stock excluded from calculations of diluted net income per share (in shares)	67,500	33,750
Class of Stock [Line Items]
Equity per common share (in dollars per share)	$ 14.14us-gaap_EarningsPerShareBasicAndDiluted	$ 13.89us-gaap_EarningsPerShareBasicAndDiluted	$ 13.64us-gaap_EarningsPerShareBasicAndDiluted
Class A Stock [Member]
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	15,000,000
Common stock, shares issued (in shares)	8,030,677	7,948,569	7,828,836
Common stock, shares outstanding (in shares)	8,030,677	7,948,569	7,828,836
Common stock, par value (in dollars per share)	$ 1.00
Common stock, shares issued during period (in shares)	82,108	119,733	99,330
Class B Stock [Member]
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	1,040,000
Common stock, shares issued (in shares)	881,452	881,452	881,452
Common stock, shares outstanding (in shares)	881,452	881,452	881,452
Common stock, par value (in dollars per share)	$ 1.00

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Number of new stock issued during the period.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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