Condensed Consolidated Statements of Shareholders' Equity - USD ($)	Common Stock [Member] Common Class A [Member]	Common Stock [Member] Common Class B [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Noncontrolling Interest [Member]	Common Class A [Member]	Common Class B [Member]	Total
Balance at Dec. 31, 2017	$ 5,000	$ 1,000	$ 10,744,000	$ 144,000	$ 867,000	$ 100,000			$ 11,861,000
Balance (in Shares) at Dec. 31, 2017	4,808,235	762,612
Consolidated net income (loss)					61,000	(2,000)			59,000
Other comprehensive income (loss)				(7,000)		1,000			(6,000)
Balance at Mar. 31, 2018	$ 5,000	$ 1,000	10,745,000	137,000	789,000	99,000			11,776,000
Balance (in Shares) at Mar. 31, 2018	4,808,235	762,612
Balance at Dec. 31, 2017	$ 5,000	$ 1,000	10,744,000	144,000	867,000	100,000			11,861,000
Balance (in Shares) at Dec. 31, 2017	4,808,235	762,612
Consolidated net income (loss)									737,000
Other comprehensive income (loss)									(6,000)
Balance at Sep. 30, 2018	$ 5,000	$ 1,000	10,806,000	138,000	1,194,000	95,000			12,239,000
Balance (in Shares) at Sep. 30, 2018	4,867,235	762,612
Balance at Mar. 31, 2018	$ 5,000	$ 1,000	10,745,000	137,000	789,000	99,000			11,776,000
Balance (in Shares) at Mar. 31, 2018	4,808,235	762,612
Consolidated net income (loss)					401,000	(2,000)			399,000
Other comprehensive income (loss)				9,000					9,000
Exercise stock options			18,000						18,000
Exercise stock options (in Shares)	20,000
Amortization of stock based compensation			1,000						1,000
Cash dividends					(139,000)				(139,000)
Balance at Jun. 30, 2018	$ 5,000	$ 1,000	10,764,000	146,000	1,051,000	97,000			12,064,000
Balance (in Shares) at Jun. 30, 2018	4,828,235	762,612
Consolidated net income (loss)					281,000	(2,000)			279,000
Other comprehensive income (loss)				(8,000)					(8,000)
Exercise stock options			42,000						42,000
Exercise stock options (in Shares)	39,000
Cash dividends					(138,000)				(138,000)
Balance at Sep. 30, 2018	$ 5,000	$ 1,000	10,806,000	138,000	1,194,000	95,000			12,239,000
Balance (in Shares) at Sep. 30, 2018	4,867,235	762,612
Balance at Dec. 31, 2018	$ 5,000	$ 1,000	10,812,000	128,000	1,656,000	96,000			12,698,000
Balance (in Shares) at Dec. 31, 2018	4,867,235	762,612					4,867,235	762,612
Consolidated net income (loss)					186,000	(2,000)			184,000
Other comprehensive income (loss)				13,000		(1,000)			12,000
Exercise stock options			76,000						76,000
Exercise stock options (in Shares)	70,000
Amortization of stock based compensation			4,000						4,000
Cash dividends					(171,000)				(171,000)
Balance at Mar. 31, 2019	$ 5,000	$ 1,000	10,892,000	141,000	1,671,000	93,000			12,803,000
Balance (in Shares) at Mar. 31, 2019	4,937,235	762,612
Balance at Dec. 31, 2018	$ 5,000	$ 1,000	10,812,000	128,000	1,656,000	96,000			12,698,000
Balance (in Shares) at Dec. 31, 2018	4,867,235	762,612					4,867,235	762,612
Consolidated net income (loss)									955,000
Other comprehensive income (loss)									$ (85,000)
Exercise stock options (in Shares)									123,000
Balance at Sep. 30, 2019	$ 5,000	$ 1,000	10,952,000	43,000	2,062,000	100,000			$ 13,163,000
Balance (in Shares) at Sep. 30, 2019	4,990,235	762,612					4,990,235	762,612
Balance at Mar. 31, 2019	$ 5,000	$ 1,000	10,892,000	141,000	1,671,000	93,000			12,803,000
Balance (in Shares) at Mar. 31, 2019	4,937,235	762,612
Consolidated net income (loss)					258,000	(2,000)			256,000
Other comprehensive income (loss)				2,000					2,000
Exercise stock options			50,000						50,000
Exercise stock options (in Shares)	53,000
Amortization of stock based compensation			5,000						5,000
Cash dividends					(172,000)				(172,000)
Balance at Jun. 30, 2019	$ 5,000	$ 1,000	10,947,000	143,000	1,757,000	91,000			12,944,000
Balance (in Shares) at Jun. 30, 2019	4,990,235	762,612
Consolidated net income (loss)					478,000	37,000			515,000
Other comprehensive income (loss)				(100,000)		(28,000)			(100,000)
Amortization of stock based compensation			5,000						5,000
Cash dividends					(173,000)				(173,000)
Balance at Sep. 30, 2019	$ 5,000	$ 1,000	$ 10,952,000	$ 43,000	$ 2,062,000	$ 100,000			$ 13,163,000
Balance (in Shares) at Sep. 30, 2019	4,990,235	762,612					4,990,235	762,612