CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Revenue	$ 1,061,000	$ 747,000
Costs and expenses:
Patient expenses	86,000	79,000
Selling, general and administrative	298,000	302,000
Total	384,000	381,000
Operating income	677,000	366,000
Interest expense	(2,000)	(11,000)
Interest income - sales-type sublease	8,000	24,000
Loss from investments in unconsolidated entities, net	(139,000)	(146,000)
Income before income taxes	544,000	233,000
Provision for income taxes	(5,000)	(58,000)
Net income	$ 539,000	$ 175,000
Basic net income per share (in dollars per share)	$ 0.07	$ 0.02
Diluted net income per share (in dollars per share)	$ 0.07	$ 0.02
Weighted average common shares outstanding (in shares)	7,792,185	7,792,185