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Note 2 - Business Combination - Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Oct. 05, 2021	Sep. 30, 2022	Dec. 31, 2021
Liabilities
Goodwill		$ 55,504	$ 53,684
Park Environmental Equipment, LLC [Member]
Assets
Cash and cash equivalents	$ 278
Trade and other receivables	11,034
Inventories	12,773
Prepaid expenses and other	293
Property and equipment	8,076
Operating lease right-of-use assets	58,301
Intangible assets	31,000
Deferred income taxes	347
Total assets acquired	122,102
Liabilities
Accounts payable	2,029
Accrued liabilities	4,067
Operating lease liabilities	58,301
Total liabilities assumed	64,397
Goodwill	32,519
Total purchase consideration	$ 90,224