CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
CURRENT ASSETS
Cash and cash equivalents	$ 0.0	$ 1.1	$ 0.0	$ 94.3
Accounts receivable, after allowance for doubtful accounts	162.3	157.8
Accrued unbilled revenues	65.0	67.6
Income taxes receivable	2.6	8.1
Fuel inventories	40.6	36.5
Materials and supplies, at average cost	117.9	116.2
Fuel clause under recoveries	151.9	0.0
Other	73.3	41.2
Total current assets	613.6	428.5
OTHER PROPERTY AND INVESTMENTS
Investment in unconsolidated affiliates	0.0	374.3	1,132.9
Equity Securities, FV-NI, Current	785.1	0.0
Other	120.0	109.8
Total other property and investments	905.1	484.1
PROPERTY, PLANT AND EQUIPMENT
In service	13,899.8	13,296.7
Construction work in progress	252.0	145.5
Total property, plant and equipment	14,151.8	13,442.2
Less: accumulated depreciation	4,318.9	4,067.6
Net property, plant and equipment	9,832.9	9,374.6
DEFERRED CHARGES AND OTHER ASSETS
Regulatory assets	1,230.8	415.6
Other	24.0	16.0
Total deferred charges and other assets	1,254.8	431.6
TOTAL ASSETS	12,606.4	10,718.8	11,024.3
Allowance for Doubtful Accounts Receivable	2.4	2.6
CURRENT LIABILITIES
Short-term debt	486.9	95.0
Accounts payable	274.0	251.5
Dividends payable	82.1	80.5
Customer deposits	81.1	81.1
Accrued taxes	52.9	55.7
Accrued interest	40.8	40.2
Accrued compensation	37.7	31.1
Long-term debt due within one year	0.0	0.0
Fuel clause over recoveries	0.0	28.6
Other	34.1	33.7
Total current liabilities	1,089.6	697.4
LONG-TERM DEBT	4,496.4	3,494.4
DEFERRED CREDITS AND OTHER LIABILITIES
Accrued benefit obligations	159.8	231.4
Deferred income taxes	1,333.3	1,268.6
Accumulated Deferred Investment Tax Credit	12.8	10.9
Regulatory liabilities	1,231.1	1,188.9
Other	227.1	195.4
Total deferred credits and other liabilities	2,964.1	2,895.2
Total liabilities	8,550.1	7,087.0
COMMITMENTS AND CONTINGENCIES (NOTE 15)
STOCKHOLDERS' EQUITY
Common stockholders' equity	1,125.8	1,124.6
Retained earnings	2,955.4	2,544.6
Accumulated other comprehensive loss, net of tax	(24.8)	(32.1)	(27.9)
Stockholders' Equity Attributable to Parent	4,056.3	3,631.8
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	12,606.4	10,718.8
Og and E [Member]
CURRENT ASSETS
Cash and cash equivalents	0.0	0.0	0.0	0.0
Accounts receivable, after allowance for doubtful accounts	162.0	156.3
Accrued unbilled revenues	65.0	67.7
Advances to parent	0.0	272.0
Fuel inventories	40.6	36.5
Materials and supplies, at average cost	117.9	116.2
Fuel clause under recoveries	151.9	0.0
Other	67.7	36.9
Total current assets	605.1	685.6
OTHER PROPERTY AND INVESTMENTS
Total other property and investments	3.9	4.1
PROPERTY, PLANT AND EQUIPMENT
In service	13,893.7	13,290.6
Construction work in progress	252.0	145.5
Total property, plant and equipment	14,145.7	13,436.1
Less: accumulated depreciation	4,318.9	4,067.6
Net property, plant and equipment	9,826.8	9,368.5
DEFERRED CHARGES AND OTHER ASSETS
Regulatory assets	1,230.8	415.6
Other	21.4	15.2
Total deferred charges and other assets	1,252.2	430.8
TOTAL ASSETS	11,688.0	10,489.0
CURRENT LIABILITIES
Accounts payable	240.6	236.7
Advances from parent	101.3	0.0
Customer deposits	81.1	81.1
Accrued taxes	50.8	53.3
Accrued interest	40.4	40.2
Accrued compensation	27.8	22.5
Long-term debt due within one year	0.0	0.0
Fuel clause over recoveries	0.0	28.6
Other	33.8	33.5
Total current liabilities	575.8	495.9
LONG-TERM DEBT	3,996.5	3,494.4
DEFERRED CREDITS AND OTHER LIABILITIES
Accrued benefit obligations	75.1	135.4
Deferred income taxes	1,000.4	1,020.8
Accumulated Deferred Investment Tax Credit	12.8	10.9
Regulatory liabilities	1,231.1	1,188.9
Other	193.5	167.1
Total deferred credits and other liabilities	2,512.9	2,523.1
Total liabilities	7,085.2	6,513.4
COMMITMENTS AND CONTINGENCIES (NOTE 15)
STOCKHOLDERS' EQUITY
Common stockholders' equity	1,571.7	1,039.5
Retained earnings	3,031.1	2,936.1
Stockholders' Equity Attributable to Parent	4,602.8	3,975.6	$ 3,958.3	$ 3,603.3
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 11,688.0	$ 10,489.0