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Note 2 - Acquisitions - Proforma Results (Details) - The 2021 Acquisitions [Member] - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Revenue, net | $ 146,966 | $ 129,782 | $ 399,372 | $ 362,918
Net earnings | $ 5,734 | $ 7,814 | $ 17,043 | $ 9,538
Common Class A [Member] |  |  |  |
Earnings per common share - basic and diluted (in dollars per share) | $ 0.44 | $ 0.60 | $ 1.31 | $ 0.72
Common Class B [Member] |  |  |  |
Earnings per common share - basic and diluted (in dollars per share) | $ 0.47 | $ 0.64 | $ 1.39 | $ 0.78

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