Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Receivables, Net
Reserve for uncollectible accounts receivable	$ 4,219	$ 3,885
Reserve for uncollectible other accounts receivable	750	931
Common shareholders' equity
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	50,000	50,000
Common stock, shares issued	34,668	34,668
Common stock, shares outstanding	34,668	34,668
MGE [Member]
Receivables, Net
Reserve for uncollectible accounts receivable	4,219	3,885
Reserve for uncollectible other accounts receivable	$ 750	$ 931
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