| Three Months Ended June 30, | Six Months Ended June 30, | ||||||||||||||||||||||
| 2024 | 2023 | 2024 | 2023 | ||||||||||||||||||||
| Operating Revenues: | |||||||||||||||||||||||
| Electric | $ | 1,521 | $ | 1,585 | $ | 2,885 | $ | 3,175 | |||||||||||||||
| Natural gas | 172 | 175 | 624 | 647 | |||||||||||||||||||
| Total operating revenues | 1,693 | 1,760 | 3,509 | 3,822 | |||||||||||||||||||
| Operating Expenses: | |||||||||||||||||||||||
| Fuel and purchased power | 327 | 480 | 655 | 1,088 | |||||||||||||||||||
| Natural gas purchased for resale | 33 | 42 | 184 | 250 | |||||||||||||||||||
| Other operations and maintenance | 465 | 450 | 935 | 898 | |||||||||||||||||||
| Depreciation and amortization | 376 | 335 | 737 | 655 | |||||||||||||||||||
| Taxes other than income taxes | 131 | 124 | 266 | 251 | |||||||||||||||||||
| Total operating expenses | 1,332 | 1,431 | 2,777 | 3,142 | |||||||||||||||||||
| Operating Income | 361 | 329 | 732 | 680 | |||||||||||||||||||
| Other Income, Net | 103 | 82 | 192 | 160 | |||||||||||||||||||
| Interest Charges | 165 | 134 | 319 | 261 | |||||||||||||||||||
| Income Before Income Taxes | 299 | 277 | 605 | 579 | |||||||||||||||||||
| Income Taxes | 39 | 38 | 83 | 75 | |||||||||||||||||||
| Net Income | 260 | 239 | 522 | 504 | |||||||||||||||||||
| Less: Net Income Attributable to Noncontrolling Interests | 2 | 2 | 3 | 3 | |||||||||||||||||||
| Net Income Attributable to Ameren Common Shareholders | $ | 258 | $ | 237 | $ | 519 | $ | 501 | |||||||||||||||
| Earnings per Common Share – Basic | $ | 0.97 | $ | 0.90 | $ | 1.95 | $ | 1.91 | |||||||||||||||
| Earnings per Common Share – Diluted | $ | 0.97 | $ | 0.90 | $ | 1.95 | $ | 1.90 | |||||||||||||||
| Weighted-average Common Shares Outstanding – Basic | 266.7 | 262.6 | 266.5 | 262.4 | |||||||||||||||||||
| Weighted-average Common Shares Outstanding – Diluted | 266.8 | 263.2 | 266.8 | 263.2 | |||||||||||||||||||
| June 30, 2024 | December 31, 2023 | ||||||||||
| ASSETS | |||||||||||
| Current Assets: | |||||||||||
| Cash and cash equivalents | $ | 19 | $ | 25 | |||||||
| Accounts receivable - trade (less allowance for doubtful accounts) | 514 | 494 | |||||||||
| Unbilled revenue | 407 | 319 | |||||||||
| Miscellaneous accounts receivable | 62 | 106 | |||||||||
| Inventories | 740 | 733 | |||||||||
| Current regulatory assets | 345 | 365 | |||||||||
| Other current assets | 130 | 139 | |||||||||
| Total current assets | 2,217 | 2,181 | |||||||||
| Property, Plant, and Equipment, Net | 34,873 | 33,776 | |||||||||
| Investments and Other Assets: | |||||||||||
| Nuclear decommissioning trust fund | 1,266 | 1,150 | |||||||||
| Goodwill | 411 | 411 | |||||||||
| Regulatory assets | 1,952 | 1,810 | |||||||||
| Pension and other postretirement benefits | 566 | 581 | |||||||||
| Other assets | 1,049 | 921 | |||||||||
| Total investments and other assets | 5,244 | 4,873 | |||||||||
| TOTAL ASSETS | $ | 42,334 | $ | 40,830 | |||||||
| LIABILITIES AND EQUITY | |||||||||||
| Current Liabilities: | |||||||||||
| Current maturities of long-term debt | $ | 799 | $ | 849 | |||||||
| Short-term debt | 691 | 536 | |||||||||
| Accounts and wages payable | 774 | 1,136 | |||||||||
| Interest accrued | 177 | 147 | |||||||||
| Customer deposits | 197 | 176 | |||||||||
| Other current liabilities | 655 | 501 | |||||||||
| Total current liabilities | 3,293 | 3,345 | |||||||||
| Long-term Debt, Net | 16,280 | 15,121 | |||||||||
| Deferred Credits and Other Liabilities: | |||||||||||
| Accumulated deferred income taxes and tax credits, net | 4,325 | 4,176 | |||||||||
| Regulatory liabilities | 5,531 | 5,512 | |||||||||
| Asset retirement obligations | 791 | 772 | |||||||||
| Other deferred credits and liabilities | 446 | 426 | |||||||||
| Total deferred credits and other liabilities | 11,093 | 10,886 | |||||||||
| Shareholders’ Equity: | |||||||||||
| Common stock | 3 | 3 | |||||||||
| Other paid-in capital, principally premium on common stock | 7,246 | 7,216 | |||||||||
| Retained earnings | 4,299 | 4,136 | |||||||||
| Accumulated other comprehensive loss | (9) | (6) | |||||||||
| Total shareholders’ equity | 11,539 | 11,349 | |||||||||
| Noncontrolling Interests | 129 | 129 | |||||||||
| Total equity | 11,668 | 11,478 | |||||||||
| TOTAL LIABILITIES AND EQUITY | $ | 42,334 | $ | 40,830 | |||||||
| Six Months Ended June 30, | |||||||||||
| 2024 | 2023 | ||||||||||
| Cash Flows From Operating Activities: | |||||||||||
| Net income | $ | 522 | $ | 504 | |||||||
| Adjustments to reconcile net income to net cash provided by operating activities: | |||||||||||
| Depreciation and amortization | 760 | 703 | |||||||||
| Amortization of nuclear fuel | 38 | 36 | |||||||||
| Amortization of debt issuance costs and premium/discounts | 9 | 8 | |||||||||
| Deferred income taxes and investment tax credits, net | 76 | 66 | |||||||||
| Allowance for equity funds used during construction | (25) | (23) | |||||||||
| Stock-based compensation costs | 14 | 14 | |||||||||
| Other | 13 | (19) | |||||||||
| Changes in assets and liabilities | (358) | (178) | |||||||||
| Net cash provided by operating activities | 1,049 | 1,111 | |||||||||
| Cash Flows From Investing Activities: | |||||||||||
| Capital expenditures | (1,892) | (1,822) | |||||||||
| Nuclear fuel expenditures | (37) | (50) | |||||||||
| Purchases of securities – nuclear decommissioning trust fund | (323) | (81) | |||||||||
| Sales and maturities of securities – nuclear decommissioning trust fund | 309 | 65 | |||||||||
| Other | 11 | (1) | |||||||||
| Net cash used in investing activities | (1,932) | (1,889) | |||||||||
| Cash Flows From Financing Activities: | |||||||||||
| Dividends on common stock | (356) | (330) | |||||||||
| Dividends paid to noncontrolling interest holders | (3) | (3) | |||||||||
| Short-term debt, net | 156 | 260 | |||||||||
| Maturities of long-term debt | (350) | (100) | |||||||||
| Issuances of long-term debt | 1,470 | 997 | |||||||||
| Issuances of common stock | 21 | 16 | |||||||||
| Employee payroll taxes related to stock-based compensation | (8) | (20) | |||||||||
| Debt issuance costs | (18) | (9) | |||||||||
| Other | — | (3) | |||||||||
| Net cash provided by financing activities | 912 | 808 | |||||||||
| Net change in cash, cash equivalents, and restricted cash | 29 | 30 | |||||||||
Cash, cash equivalents, and restricted cash at beginning of year(a) | 272 | 216 | |||||||||
Cash, cash equivalents, and restricted cash at end of period(b) | $ | 301 | $ | 246 | |||||||
