EARNINGS (LOSS) PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Numerator [Abstract]
Net earnings (loss)	$ 1,131	$ (1,303)
Undistributed earnings (loss)	293	(2,133)
Class A [Member]
Numerator [Abstract]
Net earnings (loss)	180	(240)
Less dividends declared	130	130
Undistributed earnings (loss)	$ 50	$ (370)
Weighted-average shares outstanding [Abstract]
Basic and diluted (in shares)	2,175	2,175
Net earnings (loss) per share [Abstract]
Basic and diluted (in dollars per share)	$ 0.08	$ (0.11)
Class B [Member]
Numerator [Abstract]
Net earnings (loss)	$ 951	$ (1,063)
Less dividends declared	708	700
Undistributed earnings (loss)	$ 243	$ (1,763)
Weighted-average shares outstanding [Abstract]
Basic and diluted (in shares)	10,089	9,856
Net earnings (loss) per share [Abstract]
Basic and diluted (in dollars per share)	$ 0.09	$ (0.11)

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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