MGE Energy Inc Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Operating Activities:
Net Income	$ 30,318	$ 30,506
Items not affecting cash:
Depreciation and amortization	19,336	20,373
Deferred income taxes	14,657	9,263
Provision for doubtful receivables	1,207	1,013
Employee benefit plan expenses	9,222	6,818
Equity earnings in ATC	(4,484)	(4,267)
Other items	1,102	725
Changes in working capital items:
Decrease in current assets	15,323	29,171
Decrease in current liabilities	(10,948)	(8,629)
Dividend income from ATC	3,494	3,327
Cash contributions to pension and other postretirement plans	(21,593)	(19,932)
Other noncurrent items, net	3,152	(945)
Cash Provided by Operating Activities	60,786	67,423
Investing Activities:
Capital expenditures	(39,553)	(28,591)
Capital contributions to investments	(938)	(691)
Purchase of investment - land	(2)	(1,801)
Other	(338)	(90)
Cash Used for Investing Activities	(40,831)	(31,173)
Financing Activities:
Cash dividends paid on common stock	(17,687)	(17,340)
Repayment of long-term debt	(29,334)	(1,167)
Issuance of long-term debt	28,000	30,000
Decrease in short-term debt	0	(22,500)
Other	(815)	(299)
Cash Used for Financing Activities	(19,836)	(11,306)
Change in Cash and Cash Equivalents:	119	24,944
Cash and cash equivalents at beginning of period	41,169	7,110
Cash and cash equivalents at end of period	41,288	32,054
Significant noncash investing activities [Abstract]
Accrued capital expenditures	$ 4,779	$ 963