Condensed Consolidated Statements of Shareholders' Equity - USD ($)	Common Class A [Member] Common Stock [Member]	Common Class A [Member]	Common Class B [Member] Common Stock [Member]	Common Class B [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Noncontrolling Interest [Member]	Total
Balance at Dec. 31, 2019	$ 5,000		$ 1,000		$ 10,959,000	$ 38,000	$ 1,712,000	$ 100,000	$ 12,815,000
Balance (in Shares) at Dec. 31, 2019	4,990,235		762,612
Consolidated net income (loss)							90,000		90,000
Exercise stock options					54,000				54,000
Exercise stock options (in Shares)	45,000
Other comprehensive income (loss)									0
Amortization of stock based compensation					6,000				6,000
Cash dividends							(201,000)		(201,000)
Balance at Mar. 31, 2020	$ 5,000		$ 1,000		11,019,000	38,000	1,601,000	$ 100,000	12,764,000
Balance (in Shares) at Mar. 31, 2020	5,035,235		762,612
Balance at Dec. 31, 2020	$ 5,000		$ 1,000		11,071,000	(66,000)	2,231,000		13,242,000
Balance (in Shares) at Dec. 31, 2020	5,062,235	5,062,235	762,612	762,612
Consolidated net income (loss)							337,000		337,000
Other comprehensive income (loss)						(13,000)			(13,000)
Amortization of stock based compensation					8,000				8,000
Cash dividends							(233,000)		(233,000)
Balance at Mar. 31, 2021	$ 5,000		$ 1,000		$ 11,079,000	$ (79,000)	$ 2,335,000		$ 13,341,000
Balance (in Shares) at Mar. 31, 2021	5,062,235	5,062,235	762,612	762,612