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MGE Energy Inc Consolidated Statements of Common Equity - USD ($) shares in Thousands, $ in Thousands | Total | Common Stock [Member] | Additional Paid-In Capital [Member] | Retained Earnings [Member] | Accumulated Other Comprehensive (Loss)/ Income [Member]
--- | --- | --- | --- | --- | ---
Beginning balance, shares at Dec. 31, 2012 |  | 34,668 |  |  |
Beginning balance, value at Dec. 31, 2012 | $ 579,429 | $ 34,668 | $ 316,268 | $ 228,399 | $ 94
Increase (Decrease) in Common Equity [Roll Forward] |  |  |  |  |
Net Income | 74,905 |  |  | 74,905 |
Other comprehensive income/(loss) | 283 |  |  |  | 283
Common stock dividends declared | (37,107) |  |  | (37,107) |
Ending balance, shares at Dec. 31, 2013 |  | 34,668 |  |  |
Ending balance, value at Dec. 31, 2013 | 617,510 | $ 34,668 | 316,268 | 266,197 | 377
Increase (Decrease) in Common Equity [Roll Forward] |  |  |  |  |
Net Income | 80,319 |  |  | 80,319 |
Other comprehensive income/(loss) | 81 |  |  |  | 81
Common stock dividends declared | (38,429) |  |  | (38,429) |
Cash in lieu of fractional shares related to stock split | (80) |  |  | (80) |
Ending balance, shares at Dec. 31, 2014 |  | 34,668 |  |  |
Ending balance, value at Dec. 31, 2014 | 659,401 | $ 34,668 | 316,268 | 308,007 | 458
Cumulative effect of new accounting principle (See Footnote 1) at Dec. 31, 2014 | (142) |  |  | (142) |
Beginning balance, value - Adjusted at Dec. 31, 2014 | 659,259 |  |  | 307,865 |
Increase (Decrease) in Common Equity [Roll Forward] |  |  |  |  |
Net Income | 71,343 |  |  | 71,343 |
Other comprehensive income/(loss) | (101) |  |  |  | (101)
Common stock dividends declared | (40,043) |  |  | (40,043) |
Ending balance, shares at Dec. 31, 2015 |  | 34,668 |  |  |
Ending balance, value at Dec. 31, 2015 | $ 690,458 | $ 34,668 | $ 316,268 | $ 339,165 | $ 357

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