Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Receivables, net of allowance for credit losses of $13.3 and $15.3, respectively	$ 13.3	$ 15.3
Regulatory assets, includes $17.1 and $16.7 related to variable interest entity, respectively	247.5	217.4
PROPERTY, PLANT AND EQUIPMENT, NET, includes $115.8 and $119.4 related to variable interest entity, respectively	27,405.6	26,301.5
Regulatory assets, includes $269.2 and $277.9 related to variable interest entity, respectively	1,959.7	1,885.3
Current maturities of long-term debt, includes $17.5 and $17.0 related to variable interest entity, respectively	1,495.3	367.0
Accrued interest, includes $1.3 and $1.3 related to variable interest entity, respectively	130.6	158.3
Long-term debt, net, includes $270.6 and $279.2 related to variable interest entity, respectively	$ 12,315.7	$ 13,039.2
Common stock - shares authorized (in shares)	600,000,000	600,000,000
Common stock - shares issued (in shares)	230,561,238	230,262,674
Variable Interest Entities
Regulatory assets, includes $17.1 and $16.7 related to variable interest entity, respectively	$ 17.1	$ 16.7
PROPERTY, PLANT AND EQUIPMENT, NET, includes $115.8 and $119.4 related to variable interest entity, respectively	115.8	119.4
Regulatory assets, includes $269.2 and $277.9 related to variable interest entity, respectively	269.2	277.9
Current maturities of long-term debt, includes $17.5 and $17.0 related to variable interest entity, respectively	17.5	17.0
Accrued interest, includes $1.3 and $1.3 related to variable interest entity, respectively	1.3	1.3
Long-term debt, net, includes $270.6 and $279.2 related to variable interest entity, respectively	$ 270.6	$ 279.2

Amount of allowance for credit loss on accounts receivable, classified as current.

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