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v3.25.3

Equity (Narrative) (Details) - USD ($) |  |  |  |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Jun. 12, 2025 | Mar. 03, 2025 | Feb. 27, 2025 | Feb. 22, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Mar. 15, 2024
Preferred Stock, Par or Stated Value Per Share |  |  |  |  |  |  |  |  | $ 25,000
Preferred Stock Shares Redeemed |  |  |  |  | 6,226,000 | 18,148,000 | 6,226,000 | 18,148,000 |
Forward Contract Indexed to Issuer's Equity, Forward Rate Per Share | $ 39.71 | $ 41.00 | $ 40.10 |  |  |  |  |  |
Preferred Stock Redemption Premium |  |  |  |  | $ 0 | $ 0 | $ 0 | $ 14,000,000.0 |
Customer revenues |  |  |  |  | 1,240,200,000 | 1,046,100,000 | 4,636,200,000 | 3,743,200,000 |
Corporate and Other |  |  |  |  |  |  |  |  |
Customer revenues | $ 2,518,393 |  |  |  | $ 0 | $ 0 | 0 | 0 |
Forward March 03 |  |  |  |  |  |  |  |  |
Forward Contract Indexed to Issuer's Equity, Forward Rate Per Share |  |  |  |  | $ 40.92 |  |  |  |
Forward February 22 |  |  |  |  |  |  |  |  |
Forward Contract Indexed to Issuer's Equity, Forward Rate Per Share |  |  |  |  | 40.02 |  |  |  |
Forward June 12 |  |  |  |  |  |  |  |  |
Forward Contract Indexed to Issuer's Equity, Forward Rate Per Share |  |  |  |  | $ 39.36 |  |  |  |
Pension Plan |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Plan Assets, Contributions by Employer |  |  |  |  |  |  | 1,500,000 | 1,900,000 |
Other Postretirement Benefit Plan |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Plan Assets, Contributions by Employer |  |  |  |  |  |  | 15,400,000 | $ 18,300,000 |
At The Market Program |  |  |  |  |  |  |  |  |
Common Stock Aggregate Sale Price |  |  |  | $ 900,000,000.0 |  |  |  |  |
ATM Program Equity Remaining Available for Issuance |  |  |  |  |  |  | $ 47,500,000 |  |
Forward February 22 |  |  |  |  |  |  |  |  |
Common Stock Aggregate Sale Price |  |  | $ 80,000,000 |  |  |  |  |  |
Forward Contract Indexed to Issuer's Equity, Shares |  |  | 2,000,000 |  |  |  |  |  |
Forward March 03 |  |  |  |  |  |  |  |  |
Common Stock Aggregate Sale Price |  |  |  |  | $ 69,900,000 |  |  |  |
Forward Contract Indexed to Issuer's Equity, Shares |  | 1,707,320 |  |  |  |  |  |  |
Forward June 12 |  |  |  |  |  |  |  |  |
Common Stock Aggregate Sale Price |  |  |  |  | $ 99,100,000 |  |  |  |
Series B Preferred Stock [Member] |  |  |  |  |  |  |  |  |
Preferred Stock, Dividends Per Share, Declared |  |  |  |  |  |  | $ 0 | $ 406.25 |
Series B-1 Preferred Stock |  |  |  |  |  |  |  |  |
Preferred Stock, Par or Stated Value Per Share |  |  |  |  |  |  |  |  | $ 0.01
Preferred Stock, Redemption Amount |  |  |  |  |  |  |  |  | $ 500,000,000
Preferred Stock, Shares Issued |  |  |  |  |  |  |  |  | 20,000

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