Note 3 - Property and Equipment - Summary of Property and Equipment (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Property and equipment, gross	$ 73,951,000	$ 76,157,000
Accumulated depreciation	(45,697,000)	(45,739,000)
Net property and equipment	28,254,000	30,418,000
Medical Equipment and Facilities [Member]
Property and equipment, gross	73,388,000	75,657,000
Office Equipment [Member]
Property and equipment, gross	472,000	330,000
Construction in Progress [Member]
Property and equipment, gross	$ 91,000	$ 170,000

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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