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New Accounting Standards | 12 Months Ended
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Dec. 31, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract] |
Adoption of Accounting Principles and Recently Issued Accounting Pronouncements | New Accounting Standards - MGE Energy and MGE. Recently Adopted Leases. In February 2016, the FASB issued authoritative guidance within the codification's Leases topic that provides guidance on the classification, recognition, measurement, and disclosure of leases. The new leasing standard establishes that a lease conveys the right to control the use of identified property, plant, or equipment for a period of time in exchange for consideration. Under the new guidance, lessees are required to recognize all leases with terms greater than one year, including operating leases, on the balance sheet by recording a right-of-use asset and lease liability. Prior to the authoritative guidance, only capital leases were recognized on the balance sheet by lessees. The new accounting guidance, as applied by lessors, did not change materially. In January 2018, the FASB issued authoritative guidance which provided an optional practical expedient to grandfather the accounting for existing and expired land easements not accounted for as a lease under the new authoritative guidance. MGE Energy and MGE adopted this practical expedient. The lease authoritative guidance became effective January 1, 2019. MGE Energy and MGE adopted the standard upon the effective date. In compliance with authorized transition guidance, MGE Energy and MGE began applying the new standard on January 1, 2019, but will continue to present periods prior to that date according to the previous authoritative standard. There was no material impact on the consolidated net income or cash flows. See Footnote 5 for further lease information.

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- Definition The entire disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -URI http://asc.fasb.org/topic&trid=2122394 + Details
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