Note 6 - Sale of Business Component - Pre-tax Profit (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Pre-tax profit	$ 167,000	$ 2,463,000
Maryland-based Facilities Maintenance Business [Member] \| Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Pre-tax profit		$ 1,332

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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