Boca Oncology Partners (Details)	1 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2012	Jun. 30, 2011 USD ($)	Jun. 30, 2023 USD ($) ft²	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) ft²	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Boca Oncology Partners [Abstract]
Recorded investments			$ 185,000		$ 185,000		$ 157,000
Condensed Income Statement Information [Abstract]
Net income			(511,000)	$ (1,291,000)	(638,000)	$ (1,786,000)	(1,572,000)
USNC's equity in (loss) income			(269,000)	(998,000)	(267,000)	(1,131,000)
Condensed Balance Sheet Information [Abstract]
Current assets			806,000		806,000		1,555,000
TOTAL ASSETS			1,007,000		1,007,000		1,747,000
Current liabilities			177,000		177,000		280,000
Equity			819,000		819,000		1,456,000	$ 3,028,000
TOTAL LIABILITIES AND EQUITY			1,007,000		1,007,000		1,747,000
Boca Oncology Partners RE, LLC ("BOPRE") [Member]
Condensed Income Statement Information [Abstract]
Rental income			0	0	0	0
Net income			7,000	14,000	18,000	31,000
Condensed Balance Sheet Information [Abstract]
Current assets			41,000		41,000		123,000
Noncurrent assets			757,000		757,000		757,000
TOTAL ASSETS			798,000		798,000		880,000
Current liabilities			0		0		0
Noncurrent liabilities			0		0		0
Equity			798,000		798,000		880,000
TOTAL LIABILITIES AND EQUITY			$ 798,000		$ 798,000		880,000
Boca Oncology Partners, LLC [Member]
Boca Oncology Partners [Abstract]
Area of real estate property (in square foot) | ft²			6,000		6,000
Boca Oncology Partners RE, LLC ("BOPRE") [Member]
Boca Oncology Partners [Abstract]
Ownership percentage			23.10%		23.10%
Recorded investments			$ 185,000		$ 185,000		$ 157,000
Condensed Income Statement Information [Abstract]
USNC's equity in (loss) income			$ 2,000	$ 4,000	$ 4,000	$ 8,000
Boca Oncology Partners RE, LLC ("BOPRE") [Member] | Boca West IMP [Member]
Boca Oncology Partners [Abstract]
Percentage of interest in medical office building		20.00%
Ownership percentage	23.75%
Additional investor purchased ownership percentage	3.75%
BOP and BOPRE [Member]
Boca Oncology Partners [Abstract]
Area of real estate property (in square foot) | ft²			32,000		32,000
Investments in unconsolidated entities		$ 225,000
Ownership percentage		22.50%