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Consolidated Balance Sheets (Unaudited) (Parentheticals) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Receivables, Net |  |
Reserve for uncollectible accounts receivable | $ 4,937 | $ 5,787
Reserve for uncollectible other accounts receivable | 1,257 | 1,290
MGE [Member] |  |
Receivables, Net |  |
Reserve for uncollectible accounts receivable | 4,937 | 5,787
Reserve for uncollectible other accounts receivable | $ 1,257 | $ 1,290

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