EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Numerator [Abstract]
Net earnings available to common stockholders	$ 6,062	$ 3,065	$ 11,382	$ 5,568
Undistributed earnings	5,250	2,281	9,761	4,000
Undistributed earnings allocation - basic and diluted [Abstract]
Total undistributed earnings	5,250	2,281	9,761	4,000
Net earnings allocation - basic and diluted [Abstract]
Net earnings available to common stockholders	6,062	3,065	11,382	5,568
Class A [Member]
Numerator [Abstract]
Net earnings available to common stockholders	1,054	545	1,981	987
Less Dividends declared:	130	131	261	261
Undistributed earnings allocation - basic and diluted [Abstract]
Total undistributed earnings	924	414	1,720	726
Net earnings allocation - basic and diluted [Abstract]
Net earnings available to common stockholders	$ 1,054	$ 545	$ 1,981	$ 987
Weighted-average shares outstanding [Abstract]
Common share - basic and diluted (in shares)	2,175	2,175	2,175	2,175
Net earnings per share [Abstract]
Common share - basic and diluted (in dollars per share)	$ 0.49	$ 0.25	$ 0.91	$ 0.45
Class B [Member]
Numerator [Abstract]
Net earnings available to common stockholders	$ 5,008	$ 2,520	$ 9,401	$ 4,581
Less Dividends declared:	682	653	1,360	1,307
Undistributed earnings allocation - basic and diluted [Abstract]
Total undistributed earnings	4,326	1,867	8,041	3,274
Net earnings allocation - basic and diluted [Abstract]
Net earnings available to common stockholders	$ 5,008	$ 2,520	$ 9,401	$ 4,581
Weighted-average shares outstanding [Abstract]
Common share - basic and diluted (in shares)	9,693	9,332	9,682	9,333
Net earnings per share [Abstract]
Common share - basic and diluted (in dollars per share)	$ 0.52	$ 0.27	$ 0.97	$ 0.49