DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
EARNINGS PER SHARE [Abstract]
Anti-dilutive securities excluded from earnings per share calculation (in shares)	0	0
Numerator [Abstract]
Net earnings (loss)	$ 20,709	$ (11,897)
Undistributed earnings (loss)	17,391	(15,176)
Class A [Member]
Numerator [Abstract]
Net earnings (loss)	3,521	(2,113)
Less dividends declared	522	522
Undistributed earnings (loss)	$ 2,999	$ (2,635)
Weighted average shares outstanding [Abstract]
Weighted average shares outstanding (in shares)	2,175	2,175
Net earnings (loss) per share [Abstract]
Basic and diluted (in dollars per share)	$ 1.62	$ (0.97)
Class B [Member]
EARNINGS PER SHARE [Abstract]
Dividend rate Class B common stock in excess of dividend rate of Class A common stock	5.00%	5.00%
Undistributed earning allocation rate of Class B common stock in excess of Class A common stock, percentage	5.00%	5.00%
Numerator [Abstract]
Net earnings (loss)	$ 17,188	$ (9,784)
Less dividends declared	2,796	2,757
Undistributed earnings (loss)	$ 14,392	$ (12,541)
Weighted average shares outstanding [Abstract]
Weighted average shares outstanding (in shares)	9,939	9,857
Net earnings (loss) per share [Abstract]
Basic and diluted (in dollars per share)	$ 1.73	$ (0.99)

Dividend rate of one class in excess of dividend rate of another class.

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Earnings allocated to one class of common stock in excess of earnings allocated to another class of stock.

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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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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The earnings that is allocated to common stock and participating securities to the extent that each security may share in earnings as if all of the earnings for the period had been distributed.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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