Quarterly Results of Operations (Unaudited), Condensed Consolidated Statements of Operations (Details) - USD ($)	3 Months Ended				6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2021	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Condensed Income Statement Information [Abstract]
Revenue	$ 0	$ 0	$ 0	$ 1,061,000	$ 1,061,000	$ 1,061,000	$ 1,061,000	$ 3,173,000
Costs and expenses [Abstract]
Patient expenses	0	0	0	86,000	86,000	86,000	86,000	361,000
Selling, general and administrative	248,000	268,000	249,000	298,000	547,000	815,000	1,063,000	1,197,000
Total	248,000	268,000	249,000	384,000	633,000	901,000	1,149,000	1,558,000
Operating (loss) income	(248,000)	(268,000)	(249,000)	677,000	428,000	160,000	(88,000)	1,615,000
Total other (expense) income [Abstract]
Interest expense	0	0	(1,000)	(2,000)	(3,000)	(3,000)	(3,000)	(25,000)
Other income	(9,000)	9,000	0	0	0	9,000
Interest income - sales-type sublease	0	0	0	8,000	8,000	8,000	8,000	72,000
Loss from investment in unconsolidated entities, net	(119,000)	(77,000)	(135,000)	(139,000)	(274,000)	(351,000)	(470,000)	(809,000)
Total other expense	(128,000)	(68,000)	(136,000)	(133,000)	(269,000)	(337,000)	(465,000)	(759,000)
(Loss) income before income taxes	(376,000)	(336,000)	(385,000)	544,000	159,000	(177,000)	(553,000)	856,000
Income tax provision	(80,000)	16,000	232,000	252,000	484,000	500,000	420,000	323,000
Net (loss) income	(296,000)	(352,000)	(617,000)	292,000	(325,000)	(677,000)	(973,000)	533,000
Net loss attributable to noncontrolling interests	92,000	0	0	0	0	0	92,000	0
Net (loss) income attributable to U.S. Neurosurgical Holdings, Inc.	$ (204,000)	$ (352,000)	$ (617,000)	$ 292,000	$ (325,000)	$ (677,000)	$ (881,000)	$ 533,000
Basic net (loss) income per share attributable to U.S. Neurosurgical Holdings, Inc. (in dollars per share)	$ (0.03)	$ (0.05)	$ (0.08)	$ 0.04	$ (0.04)	$ (0.09)	$ (0.11)	$ 0.07
Diluted net (loss) income per share attributable to U.S. Neurosurgical Holdings, Inc. (in dollars per share)	$ (0.03)	$ (0.05)	$ (0.08)	$ 0.04	$ (0.04)	$ (0.09)	$ (0.11)	$ 0.07