This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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The Company and its Significant Accounting Policies, Investments in Unconsolidated Entities (Details) - USD ($)	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Investments in Unconsolidated Entities [Abstract]
Investments in unconsolidated entities	$ 141,000	$ 152,000	$ 164,000	$ 161,000	$ 160,000
Medical Oncology Partners LLC [Member]
Investments in Unconsolidated Entities [Abstract]
Investments in unconsolidated entities	0
CB Oncology Partners LLC [Member]
Investments in Unconsolidated Entities [Abstract]
Investments in unconsolidated entities	$ 0