Florida Oncology Partners (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Sep. 30, 2010
Schedule of Equity Method Investments [Line Items]
Recorded investments	$ 308,000		$ 308,000		$ 246,000
Outstanding lease obligation	4,546,000		4,546,000
FOP and FOPRE Condensed Income Statement Information [Abstract]
Patient revenue	0	469,000	0	1,064,000
USNC's equity in income (loss)	19,000	6,000	12,000	(15,000)
FOP and FOPRE [Member]
Schedule of Equity Method Investments [Line Items]
Recorded investments	151,000	135,000	151,000	135,000		200,000
Ownership percentage (in hundredths)	20.00%		20.00%
Ownership percentage by outside investors (in hundredths)			80.00%
Capital leases, amount	5,600,000		5,600,000
Percentage of guarantee obligations (in hundredths)			20.00%
Outstanding Loan	1,502,000	1,534,275	1,502,000	1,534,275
Loan amount to be paid in monthly basis			8,500
Debt maturity period			120 months
Maturity sate			Jun. 15, 2022
FOP and FOPRE Condensed Income Statement Information [Abstract]
Patient revenue	812,000	922,000	1,469,000	1,483,000
Rental income	45,000	0	90,000	0
Net sales	857,000	922,000	1,559,000	1,483,000
Net income (loss)	116,000	250,000	81,000	186,000
USNC's equity in income (loss)	23,000	50,000	16,000	37,000
FOP and FOPRE Condensed Balance Sheet Information [Abstract]
Current assets	1,206,000		1,206,000		919,000
Noncurrent assets	6,121,000		6,121,000		6,374,000
Total assets	7,327,000		7,327,000		7,293,000
Current liabilities	1,332,000		1,332,000		965,000
Noncurrent liabilities	5,320,000		5,320,000		5,734,000
Equity	675,000		675,000		594,000
Total liabilities and equity	$ 7,327,000		$ 7,327,000		$ 7,293,000