| Three Months Ended March 31, | |||||||||||
| 2022 | 2021 | ||||||||||
| Operating Revenues: | |||||||||||
| Electric | $ | 1,318 | $ | 1,156 | |||||||
| Natural gas | 561 | 410 | |||||||||
| Total operating revenues | 1,879 | 1,566 | |||||||||
| Operating Expenses: | |||||||||||
| Fuel | 176 | 65 | |||||||||
| Purchased power | 177 | 191 | |||||||||
| Natural gas purchased for resale | 293 | 165 | |||||||||
| Other operations and maintenance | 461 | 420 | |||||||||
| Depreciation and amortization | 299 | 281 | |||||||||
| Taxes other than income taxes | 142 | 128 | |||||||||
| Total operating expenses | 1,548 | 1,250 | |||||||||
| Operating Income | 331 | 316 | |||||||||
| Other Income, Net | 60 | 46 | |||||||||
| Interest Charges | 104 | 100 | |||||||||
| Income Before Income Taxes | 287 | 262 | |||||||||
| Income Taxes | 34 | 27 | |||||||||
| Net Income | 253 | 235 | |||||||||
| Less: Net Income Attributable to Noncontrolling Interests | 1 | 2 | |||||||||
| Net Income Attributable to Ameren Common Shareholders | $ | 252 | $ | 233 | |||||||
| Earnings per Common Share – Basic | $ | 0.98 | $ | 0.92 | |||||||
| Earnings per Common Share – Diluted | $ | 0.97 | $ | 0.91 | |||||||
| Weighted-average Common Shares Outstanding – Basic | 257.9 | 254.4 | |||||||||
| Weighted-average Common Shares Outstanding – Diluted | 259.0 | 255.9 | |||||||||
| March 31, 2022 | December 31, 2021 | ||||||||||
| ASSETS | |||||||||||
| Current Assets: | |||||||||||
| Cash and cash equivalents | $ | 7 | $ | 8 | |||||||
| Accounts receivable - trade (less allowance for doubtful accounts) | 560 | 434 | |||||||||
| Unbilled revenue | 283 | 301 | |||||||||
| Miscellaneous accounts receivable | 87 | 85 | |||||||||
| Inventories | 520 | 592 | |||||||||
| Mark-to-market derivative assets | 137 | 66 | |||||||||
| Current regulatory assets | 244 | 319 | |||||||||
| Current collateral assets | 110 | 66 | |||||||||
| Other current assets | 83 | 97 | |||||||||
| Total current assets | 2,031 | 1,968 | |||||||||
| Property, Plant, and Equipment, Net | 29,578 | 29,261 | |||||||||
| Investments and Other Assets: | |||||||||||
| Nuclear decommissioning trust fund | 1,094 | 1,159 | |||||||||
| Goodwill | 411 | 411 | |||||||||
| Regulatory assets | 1,377 | 1,289 | |||||||||
| Pension and other postretirement benefits | 772 | 756 | |||||||||
| Other assets | 934 | 891 | |||||||||
| Total investments and other assets | 4,588 | 4,506 | |||||||||
| TOTAL ASSETS | $ | 36,197 | $ | 35,735 | |||||||
| LIABILITIES AND EQUITY | |||||||||||
| Current Liabilities: | |||||||||||
| Current maturities of long-term debt | $ | 505 | $ | 505 | |||||||
| Short-term debt | 1,101 | 545 | |||||||||
| Accounts and wages payable | 690 | 1,095 | |||||||||
| Current regulatory liabilities | 219 | 113 | |||||||||
| Other current liabilities | 630 | 568 | |||||||||
| Total current liabilities | 3,145 | 2,826 | |||||||||
| Long-term Debt, Net | 12,563 | 12,562 | |||||||||
| Deferred Credits and Other Liabilities: | |||||||||||
| Accumulated deferred income taxes and tax credits, net | 3,550 | 3,499 | |||||||||
| Regulatory liabilities | 5,841 | 5,848 | |||||||||
| Asset retirement obligations | 769 | 757 | |||||||||
| Other deferred credits and liabilities | 394 | 414 | |||||||||
| Total deferred credits and other liabilities | 10,554 | 10,518 | |||||||||
| Shareholders’ Equity: | |||||||||||
| Common stock | 3 | 3 | |||||||||
| Other paid-in capital, principally premium on common stock | 6,507 | 6,502 | |||||||||
| Retained earnings | 3,282 | 3,182 | |||||||||
| Accumulated other comprehensive income | 14 | 13 | |||||||||
| Total shareholders’ equity | 9,806 | 9,700 | |||||||||
| Noncontrolling Interests | 129 | 129 | |||||||||
| Total equity | 9,935 | 9,829 | |||||||||
| TOTAL LIABILITIES AND EQUITY | $ | 36,197 | $ | 35,735 | |||||||
| Three Months Ended March 31, | |||||||||||
| 2022 | 2021 | ||||||||||
| Cash Flows From Operating Activities: | |||||||||||
| Net income | $ | 253 | $ | 235 | |||||||
| Adjustments to reconcile net income to net cash provided by operating activities: | |||||||||||
| Depreciation and amortization | 324 | 295 | |||||||||
| Amortization of nuclear fuel | 22 | — | |||||||||
| Amortization of debt issuance costs and premium/discounts | 4 | 5 | |||||||||
| Deferred income taxes and investment tax credits, net | 31 | 26 | |||||||||
| Allowance for equity funds used during construction | (8) | (7) | |||||||||
| Stock-based compensation costs | 4 | 6 | |||||||||
| Other | 11 | 8 | |||||||||
| Changes in assets and liabilities | (253) | (603) | |||||||||
| Net cash provided by (used in) operating activities | 388 | (35) | |||||||||
| Cash Flows From Investing Activities: | |||||||||||
| Capital expenditures | (774) | (887) | |||||||||
| Nuclear fuel expenditures | (16) | (1) | |||||||||
| Purchases of securities – nuclear decommissioning trust fund | (97) | (152) | |||||||||
| Sales and maturities of securities – nuclear decommissioning trust fund | 92 | 150 | |||||||||
| Other | 15 | 1 | |||||||||
| Net cash used in investing activities | (780) | (889) | |||||||||
| Cash Flows From Financing Activities: | |||||||||||
| Dividends on common stock | (152) | (140) | |||||||||
| Dividends paid to noncontrolling interest holders | (1) | (2) | |||||||||
| Short-term debt, net | 555 | 399 | |||||||||
| Issuances of long-term debt | — | 450 | |||||||||
| Issuances of common stock | 5 | 125 | |||||||||
| Redemptions of Ameren Illinois preferred stock | — | (13) | |||||||||
| Employee payroll taxes related to stock-based compensation | (16) | (17) | |||||||||
| Debt issuance costs | — | (3) | |||||||||
| Other | — | (4) | |||||||||
| Net cash provided by financing activities | 391 | 795 | |||||||||
| Net change in cash, cash equivalents, and restricted cash | (1) | (129) | |||||||||
| Cash, cash equivalents, and restricted cash at beginning of year | 155 | 301 | |||||||||
| Cash, cash equivalents, and restricted cash at end of period | $ | 154 | $ | 172 | |||||||