EARNINGS PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share by Two Class Method [Line Items]
Potential common shares outstanding which would have had a dilutive effect on earnings per share (in shares)	0	0
Numerator [Abstract]
Net earnings available to common stockholders	$ 5,568us-gaap_NetIncomeLoss	$ 2,503us-gaap_NetIncomeLoss
Undistributed earnings	4,759us-gaap_UndistributedEarnings	1,719us-gaap_UndistributedEarnings
Undistributed earnings allocation - basic and diluted [Abstract]
Total undistributed earnings	4,759us-gaap_UndistributedEarningsDiluted	1,719us-gaap_UndistributedEarningsDiluted
Net earnings allocation basic and diluted [Abstract]
Net earnings available to common stockholders	5,568us-gaap_NetIncomeLoss	2,503us-gaap_NetIncomeLoss
Class A [Member]
Numerator [Abstract]
Net earnings available to common stockholders	970	442
Less Dividends declared:	131	130
Undistributed earnings allocation - basic and diluted [Abstract]
Total undistributed earnings	839	312
Net earnings allocation basic and diluted [Abstract]
Net earnings available to common stockholders	970	442
Weighted-average number of shares outstanding:
Common share - basic and diluted (in shares)	2,175	2,175
Earnings per share [Abstract]
Common share - basic and diluted (in dollars per share)	$ 0.45	$ 0.20
Class B [Member]
Numerator [Abstract]
Net earnings available to common stockholders	4,598	2,061
Less Dividends declared:	678	654
Undistributed earnings allocation - basic and diluted [Abstract]
Total undistributed earnings	3,920	1,407
Net earnings allocation basic and diluted [Abstract]
Net earnings available to common stockholders	$ 4,598	$ 2,061
Weighted-average number of shares outstanding:
Common share - basic and diluted (in shares)	9,670	9,335
Earnings per share [Abstract]
Common share - basic and diluted (in dollars per share)	$ 0.48	$ 0.22

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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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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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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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