Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Receivables, Net
Reserve for uncollectible accounts receivable	$ 4,329	$ 4,219
Reserve for uncollectible other accounts receivable	420	750
Common shareholders' equity
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	75,000us-gaap_CommonStockSharesAuthorized	50,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	34,668us-gaap_CommonStockSharesIssued	34,668us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	34,668us-gaap_CommonStockSharesOutstanding	34,668us-gaap_CommonStockSharesOutstanding
MGE [Member]
Receivables, Net
Reserve for uncollectible accounts receivable	4,329	4,219
Reserve for uncollectible other accounts receivable	$ 420	$ 750
Common shareholders' equity
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	50,000	50,000
Common stock, shares outstanding	17,348	17,348

The valuation allowance as of the balance sheet date to reduce the gross amount of receivables to estimated net realizable value, which would be presented in parentheses on the face of the balance sheet.

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