Document_and_Entity_Informatio
Document and Entity Information | 9 Months Ended | |
Sep. 30, 2013 | Oct. 31, 2013 | |
Entity Information [Line Items] | ' | ' |
Document Type | '10-Q | ' |
Amendment Flag | 'false | ' |
Document Period End Date | 30-Sep-13 | ' |
Document Fiscal Year Focus | '2013 | ' |
Document Fiscal Period Focus | 'Q3 | ' |
Trading Symbol | 'AEE | ' |
Entity Registrant Name | 'AMEREN CORP | ' |
Entity Central Index Key | '0001002910 | ' |
Current Fiscal Year End Date | '--09-30 | ' |
Entity Filer Category | 'Large Accelerated Filer | ' |
Entity Common Stock, Shares Outstanding | ' | 242,634,671 |
Union Electric Company | ' | ' |
Entity Information [Line Items] | ' | ' |
Document Type | '10-Q | ' |
Amendment Flag | 'false | ' |
Document Period End Date | 30-Sep-13 | ' |
Document Fiscal Year Focus | '2013 | ' |
Document Fiscal Period Focus | 'Q3 | ' |
Entity Registrant Name | 'UNION ELECTRIC CO | ' |
Entity Central Index Key | '0000100826 | ' |
Current Fiscal Year End Date | '--09-30 | ' |
Entity Filer Category | 'Non-accelerated Filer | ' |
Entity Common Stock, Shares Outstanding | ' | 102,123,834 |
Ameren Illinois Company | ' | ' |
Entity Information [Line Items] | ' | ' |
Document Type | '10-Q | ' |
Amendment Flag | 'false | ' |
Document Period End Date | 30-Sep-13 | ' |
Document Fiscal Year Focus | '2013 | ' |
Document Fiscal Period Focus | 'Q3 | ' |
Entity Registrant Name | 'AMEREN ILLINOIS CO | ' |
Entity Central Index Key | '0000018654 | ' |
Current Fiscal Year End Date | '--09-30 | ' |
Entity Filer Category | 'Non-accelerated Filer | ' |
Entity Common Stock, Shares Outstanding | ' | 25,452,373 |
Consolidated_Statement_of_Inco
Consolidated Statement of Income (Loss) (USD $) | 3 Months Ended | 9 Months Ended | ||||||
In Millions, except Per Share data, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | ||||
Operating Revenues: | ' | ' | ' | ' | ||||
Electric | $1,507 | $1,579 | $3,823 | $3,898 | ||||
Gas | 131 | 130 | 693 | 625 | ||||
Total operating revenues | 1,638 | 1,709 | 4,516 | 4,523 | ||||
Operating Expenses: | ' | ' | ' | ' | ||||
Fuel | 222 | 194 | 648 | 550 | ||||
Purchased power | 128 | 260 | 400 | 630 | ||||
Gas purchased for resale | 42 | 40 | 344 | 304 | ||||
Other operations and maintenance | 383 | 362 | 1,229 | 1,126 | ||||
Depreciation and amortization | 175 | 161 | 528 | 496 | ||||
Taxes other than income taxes | 121 | 114 | 354 | 337 | ||||
Total operating expenses | 1,071 | 1,131 | 3,503 | 3,443 | ||||
Operating Income | 567 | 578 | 1,013 | 1,080 | ||||
Other Income and Expenses: | ' | ' | ' | ' | ||||
Miscellaneous income | 20 | [1] | 17 | [1] | 51 | [1] | 53 | [1] |
Miscellaneous expense | 5 | [1] | 6 | [1] | 18 | [1] | 28 | [1] |
Total other income (expense) | 15 | 11 | 33 | 25 | ||||
Interest Charges | 88 | 99 | 289 | 295 | ||||
Income Before Income Taxes | 494 | 490 | 757 | 810 | ||||
Income Taxes | 187 | 179 | 288 | 298 | ||||
Income from Continuing Operations | 307 | 311 | 469 | 512 | ||||
Income (Loss) from Discontinued Operations, Net of Taxes (Note 2) | -3 | 63 | -212 | -331 | ||||
Net Income | 304 | 374 | 257 | 181 | ||||
Pension and other postretirement benefit plan activity, net of income taxes (benefit) | -5 | 0 | 5 | 1 | ||||
Comprehensive Income (Loss) | 292 | 406 | 241 | 234 | ||||
Less: Net Income (Loss) Attributable to Noncontrolling Interests: | ' | ' | ' | ' | ||||
Continuing Operations | 2 | 2 | 5 | 5 | ||||
Discontinued Operations | ' | -2 | ' | -6 | ||||
Net Income (Loss): | ' | ' | ' | ' | ||||
Continuing Operations | 305 | 309 | 464 | 507 | ||||
Discontinued Operations | -3 | 65 | -212 | -325 | ||||
Net Income (Loss) | 302 | 374 | 252 | 182 | ||||
Earnings (Loss) per Common Share – Basic | ' | ' | ' | ' | ||||
Continuing Operations - Basic | $1.26 | $1.28 | $1.92 | $2.09 | ||||
Discontinued Operations - Basic | ($0.01) | $0.26 | ($0.88) | ($1.34) | ||||
Earnings per Common Share - Basic | $1.25 | $1.54 | $1.04 | $0.75 | ||||
Earnings (Loss) per Common Stock - Diluted | ' | ' | ' | ' | ||||
Continuing Operations - Diluted | $1.25 | $1.28 | $1.91 | $2.09 | ||||
Discontinued Operations - Diluted | ($0.01) | $0.26 | ($0.88) | ($1.34) | ||||
Earnings per Common Share - Diluted | $1.24 | $1.54 | $1.03 | $0.75 | ||||
Dividends per Common Share | $0.40 | $0.40 | $1.20 | $1.20 | ||||
Average Common Shares Outstanding - Basic | 242.6 | 242.6 | 242.6 | 242.6 | ||||
Average Common Shares Outstanding - Diluted | 245.1 | 242.9 | 244.4 | 242.9 | ||||
Union Electric Company | ' | ' | ' | ' | ||||
Operating Revenues: | ' | ' | ' | ' | ||||
Electric | 1,075 | 1,046 | 2,667 | 2,504 | ||||
Gas | 17 | 18 | 110 | 94 | ||||
Other | 1 | ' | 1 | 1 | ||||
Total operating revenues | 1,093 | 1,064 | 2,778 | 2,599 | ||||
Operating Expenses: | ' | ' | ' | ' | ||||
Fuel | 222 | 192 | 648 | 549 | ||||
Purchased power | 33 | 37 | 100 | 57 | ||||
Gas purchased for resale | 4 | 5 | 52 | 42 | ||||
Other operations and maintenance | 212 | 203 | 686 | 611 | ||||
Depreciation and amortization | 114 | 111 | 338 | 328 | ||||
Taxes other than income taxes | 91 | 87 | 247 | 236 | ||||
Total operating expenses | 676 | 635 | 2,071 | 1,823 | ||||
Operating Income | 417 | 429 | 707 | 776 | ||||
Other Income and Expenses: | ' | ' | ' | ' | ||||
Miscellaneous income | 16 | 15 | 44 | 48 | ||||
Miscellaneous expense | 2 | 4 | 10 | 11 | ||||
Total other income (expense) | 14 | 11 | 34 | 37 | ||||
Interest Charges | 43 | 55 | 159 | 167 | ||||
Income Before Income Taxes | 388 | 385 | 582 | 646 | ||||
Income Taxes | 149 | 148 | 217 | 243 | ||||
Net Income | 239 | 237 | 365 | 403 | ||||
Other Comprehensive Income | 0 | 0 | 0 | 0 | ||||
Comprehensive Income (Loss) | 239 | 237 | 365 | 403 | ||||
Net Income (Loss): | ' | ' | ' | ' | ||||
Net Income (Loss) | 239 | 237 | 365 | 403 | ||||
Earnings (Loss) per Common Stock - Diluted | ' | ' | ' | ' | ||||
Preferred Stock Dividends | 1 | 1 | 3 | 3 | ||||
Net Income Available to Common Stockholder | 238 | 236 | 362 | 400 | ||||
Ameren Illinois Company | ' | ' | ' | ' | ||||
Operating Revenues: | ' | ' | ' | ' | ||||
Electric | 432 | 536 | 1,160 | 1,404 | ||||
Gas | 115 | 112 | 585 | 532 | ||||
Other | ' | ' | 2 | ' | ||||
Total operating revenues | 547 | 648 | 1,747 | 1,936 | ||||
Operating Expenses: | ' | ' | ' | ' | ||||
Purchased power | 96 | 224 | 303 | 576 | ||||
Gas purchased for resale | 38 | 35 | 292 | 262 | ||||
Other operations and maintenance | 166 | 159 | 538 | 513 | ||||
Depreciation and amortization | 59 | 55 | 182 | 165 | ||||
Taxes other than income taxes | 30 | 24 | 102 | 94 | ||||
Total operating expenses | 389 | 497 | 1,417 | 1,610 | ||||
Operating Income | 158 | 151 | 330 | 326 | ||||
Other Income and Expenses: | ' | ' | ' | ' | ||||
Miscellaneous income | 4 | 2 | 7 | 5 | ||||
Miscellaneous expense | 3 | 2 | 7 | 15 | ||||
Total other income (expense) | 1 | ' | ' | -10 | ||||
Interest Charges | 31 | 34 | 96 | 98 | ||||
Income Before Income Taxes | 128 | 117 | 234 | 218 | ||||
Income Taxes | 51 | 46 | 93 | 86 | ||||
Net Income | 77 | 71 | 141 | 132 | ||||
Pension and other postretirement benefit plan activity, net of income taxes (benefit) | ' | -1 | -2 | -3 | ||||
Comprehensive Income (Loss) | 77 | 70 | 139 | 129 | ||||
Net Income (Loss): | ' | ' | ' | ' | ||||
Net Income (Loss) | 77 | 71 | 141 | 132 | ||||
Earnings (Loss) per Common Stock - Diluted | ' | ' | ' | ' | ||||
Preferred Stock Dividends | ' | ' | 2 | 2 | ||||
Net Income Available to Common Stockholder | $77 | $71 | $139 | $130 | ||||
[1] | Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations. |
Consolidated_Statement_of_Inco1
Consolidated Statement of Income (Loss) (Parenthetical) (USD $) | 3 Months Ended | 9 Months Ended | ||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 |
Pension and other postretirement benefit plan activity, tax expense (benefit) | ($5) | $0 | $3 | $0 |
Ameren Illinois Company | ' | ' | ' | ' |
Pension and other postretirement benefit plan activity, tax expense (benefit) | ($1) | ($1) | ($2) | ($2) |
Consolidated_Statement_of_Comp
Consolidated Statement of Comprehensive Income (Loss) (USD $) | 3 Months Ended | 9 Months Ended | ||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 |
Income from Continuing Operations | $307 | $311 | $469 | $512 |
Other Comprehensive Income (Loss), Net of Taxes | ' | ' | ' | ' |
Pension and other postretirement benefit plan activity, net of income taxes (benefit) | -5 | 0 | 5 | 1 |
Other Comprehensive Income (Loss), Net of Taxes | -5 | 0 | 5 | 1 |
Comprehensive Income from Continuing Operations | 302 | 311 | 474 | 513 |
Less: Comprehensive Income from Continuing Operations Attributable to Noncontrolling Interests | 2 | 2 | 5 | 5 |
Comprehensive Income from Continuing Operations Attributable to Ameren Corporation | 300 | 309 | 469 | 508 |
Income (Loss) from Discontinued Operations, Net of Taxes | -3 | 63 | -212 | -331 |
Other Comprehensive Income (Loss) from Discontinued Operations, Net of Taxes | -5 | 41 | -16 | 60 |
Comprehensive Income (Loss) from Discontinued Operations | -8 | 104 | -228 | -271 |
Less: Comprehensive Income from Discontinued Operations Attributable to Noncontrolling Interest | 0 | 7 | 0 | 3 |
Comprehensive Income (Loss) from Discontinued Operations Attributable to Ameren Corporation | -8 | 97 | -228 | -274 |
Comprehensive Income (Loss) | $292 | $406 | $241 | $234 |
Consolidated_Balance_Sheet
Consolidated Balance Sheet (USD $) | Sep. 30, 2013 | Dec. 31, 2012 | ||
In Millions, unless otherwise specified | ||||
Current Assets: | ' | ' | ||
Cash and cash equivalents | $169 | $184 | ||
Accounts receivable - trade (less allowance for doubtful accounts) | 469 | 354 | ||
Unbilled revenue | 226 | 291 | ||
Miscellaneous accounts and notes receivable | 109 | 71 | ||
Materials and supplies | 581 | 570 | ||
Current regulatory assets | 173 | 247 | ||
Current accumulated deferred income taxes, net | 43 | 170 | ||
Other current assets | 108 | 98 | ||
Assets of discontinued operations (Note 2) | 1,395 | 1,600 | ||
Total current assets | 3,273 | 3,585 | ||
Property and Plant, Net | 15,834 | 15,348 | ||
Investments and Other Assets: | ' | ' | ||
Nuclear decommissioning trust fund | 459 | 408 | ||
Goodwill | 411 | 411 | ||
Intangible assets | 19 | 14 | ||
Regulatory assets | 1,729 | 1,786 | ||
Other assets | 660 | 667 | ||
Total investments and other assets | 3,278 | 3,286 | ||
TOTAL ASSETS | 22,385 | 22,219 | ||
Current Liabilities: | ' | ' | ||
Current maturities of long-term debt | 884 | 355 | ||
Accounts and wages payable | 414 | 533 | ||
Taxes accrued | 159 | 50 | ||
Interest accrued | 120 | 89 | ||
Customer deposits | 106 | 107 | ||
Mark-to-market derivative liabilities | 65 | 92 | ||
Current regulatory liabilities | 149 | 100 | ||
Other current liabilities | 190 | 168 | ||
Liabilities of discontinued operations (Note 2) | 1,141 | 1,166 | ||
Total current liabilities | 3,228 | 2,660 | ||
Long-term Debt, Net | 5,274 | 5,802 | ||
Deferred Credits and Other Liabilities: | ' | ' | ||
Accumulated deferred income taxes, net | 3,422 | 3,176 | ||
Accumulated deferred investment tax credits | 65 | 70 | ||
Regulatory liabilities | 1,703 | 1,589 | ||
Asset retirement obligations | 392 | 375 | ||
Pension and other postretirement benefits | 1,042 | 1,138 | ||
Other deferred credits and liabilities | 534 | 642 | ||
Total deferred credits and other liabilities | 7,158 | 6,990 | ||
Commitments and Contingencies | ' | ' | ||
Stockholders' Equity: | ' | ' | ||
Common Stock | 2 | 2 | ||
Other paid-in capital | 5,624 | 5,616 | ||
Retained earnings | 967 | 1,006 | ||
Accumulated other comprehensive income (loss) | -19 | -8 | ||
Stockholder's equity | 6,574 | 6,616 | ||
Noncontrolling Interest | 151 | [1] | 151 | [1] |
Total equity | 6,725 | 6,767 | ||
TOTAL LIABILITIES AND EQUITY | 22,385 | 22,219 | ||
Union Electric Company | ' | ' | ||
Current Assets: | ' | ' | ||
Cash and cash equivalents | 100 | 148 | ||
Advances to money pool | ' | 24 | ||
Accounts receivable - trade (less allowance for doubtful accounts) | 270 | 161 | ||
Accounts receivable - affiliates | 9 | 4 | ||
Unbilled revenue | 151 | 145 | ||
Miscellaneous accounts and notes receivable | 76 | 48 | ||
Materials and supplies | 370 | 397 | ||
Current regulatory assets | 124 | 163 | ||
Other current assets | 65 | 69 | ||
Total current assets | 1,165 | 1,159 | ||
Property and Plant, Net | 10,337 | 10,161 | ||
Investments and Other Assets: | ' | ' | ||
Nuclear decommissioning trust fund | 459 | 408 | ||
Intangible assets | 19 | 14 | ||
Regulatory assets | 808 | 852 | ||
Other assets | 443 | 449 | ||
Total investments and other assets | 1,729 | 1,723 | ||
TOTAL ASSETS | 13,231 | 13,043 | ||
Current Liabilities: | ' | ' | ||
Current maturities of long-term debt | 309 | 205 | ||
Accounts and wages payable | 186 | 345 | ||
Accounts payable - affiliates | 61 | 66 | ||
Taxes accrued | 288 | 28 | ||
Interest accrued | 67 | 60 | ||
Current regulatory liabilities | 61 | 18 | ||
Other current liabilities | 97 | 77 | ||
Total current liabilities | 1,069 | 799 | ||
Long-term Debt, Net | 3,697 | 3,801 | ||
Deferred Credits and Other Liabilities: | ' | ' | ||
Accumulated deferred income taxes, net | 2,472 | 2,443 | ||
Accumulated deferred investment tax credits | 61 | 64 | ||
Regulatory liabilities | 1,002 | 917 | ||
Asset retirement obligations | 362 | 346 | ||
Pension and other postretirement benefits | 423 | 461 | ||
Other deferred credits and liabilities | 49 | 158 | ||
Total deferred credits and other liabilities | 4,369 | 4,389 | ||
Commitments and Contingencies | ' | ' | ||
Stockholders' Equity: | ' | ' | ||
Common Stock | 511 | 511 | ||
Other paid-in capital | 1,556 | 1,556 | ||
Preferred stock not subject to mandatory redemption | 80 | 80 | ||
Retained earnings | 1,949 | 1,907 | ||
Stockholder's equity | 4,096 | 4,054 | ||
TOTAL LIABILITIES AND EQUITY | 13,231 | 13,043 | ||
Ameren Illinois Company | ' | ' | ||
Current Assets: | ' | ' | ||
Cash and cash equivalents | 1 | ' | ||
Accounts receivable - trade (less allowance for doubtful accounts) | 185 | 182 | ||
Accounts receivable - affiliates | 28 | 10 | ||
Unbilled revenue | 75 | 146 | ||
Miscellaneous accounts and notes receivable | 8 | 22 | ||
Materials and supplies | 211 | 173 | ||
Current regulatory assets | 49 | 84 | ||
Current accumulated deferred income taxes, net | 35 | 85 | ||
Other current assets | 33 | 47 | ||
Total current assets | 625 | 749 | ||
Property and Plant, Net | 5,369 | 5,052 | ||
Investments and Other Assets: | ' | ' | ||
Tax receivable - Genco | 37 | 39 | ||
Goodwill | 411 | 411 | ||
Regulatory assets | 916 | 934 | ||
Other assets | 81 | 97 | ||
Total investments and other assets | 1,445 | 1,481 | ||
TOTAL ASSETS | 7,439 | 7,282 | ||
Current Liabilities: | ' | ' | ||
Current maturities of long-term debt | 150 | 150 | ||
Borrowings from money pool | 21 | 24 | ||
Accounts and wages payable | 189 | 146 | ||
Accounts payable - affiliates | 86 | 86 | ||
Taxes accrued | 17 | 18 | ||
Customer deposits | 81 | 85 | ||
Mark-to-market derivative liabilities | 48 | 77 | ||
Current environmental remediation | 53 | 37 | ||
Current regulatory liabilities | 88 | 82 | ||
Other current liabilities | 114 | 92 | ||
Total current liabilities | 847 | 797 | ||
Long-term Debt, Net | 1,577 | 1,577 | ||
Deferred Credits and Other Liabilities: | ' | ' | ||
Accumulated deferred income taxes, net | 1,095 | 1,025 | ||
Accumulated deferred investment tax credits | 4 | 5 | ||
Regulatory liabilities | 701 | 672 | ||
Pension and other postretirement benefits | 376 | 406 | ||
Environmental remediation | 194 | 216 | ||
Other deferred credits and liabilities | 152 | 183 | ||
Total deferred credits and other liabilities | 2,522 | 2,507 | ||
Commitments and Contingencies | ' | ' | ||
Stockholders' Equity: | ' | ' | ||
Common Stock | 0 | 0 | ||
Other paid-in capital | 1,965 | 1,965 | ||
Preferred stock not subject to mandatory redemption | 62 | 62 | ||
Retained earnings | 454 | 360 | ||
Accumulated other comprehensive income (loss) | 12 | 14 | ||
Stockholder's equity | 2,493 | 2,401 | ||
TOTAL LIABILITIES AND EQUITY | $7,439 | $7,282 | ||
[1] | Includes the 20% EEI ownership interest not owned by Ameren. The assets and liabilities of EEI were consolidated in Ameren’s balance sheet at a 100% ownership level and were included in “Current assets of discontinued operations†and “Current liabilities of discontinued operations.†The 20% ownership interest not owned by Ameren was included in “Noncontrolling interests†on Ameren’s September 30, 2013, and December 31, 2012 balance sheets. See Note 2 - Divestiture Transactions and Discontinued Operations for additional information. |
Consolidated_Balance_Sheet_Par
Consolidated Balance Sheet (Parenthetical) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 |
In Millions, except Per Share data, unless otherwise specified | ||
Accounts receivable - trade allowance for doubtful accounts | $20 | $17 |
Common stock, par value | $0.01 | $0.01 |
Common stock, shares authorized | 400 | 400 |
Common stock, shares outstanding | 242.6 | 242.6 |
Union Electric Company | ' | ' |
Accounts receivable - trade allowance for doubtful accounts | 7 | 5 |
Common stock, par value | $5 | $5 |
Common stock, shares authorized | 150 | 150 |
Common stock, shares outstanding | 102.1 | 102.1 |
Ameren Illinois Company | ' | ' |
Accounts receivable - trade allowance for doubtful accounts | $13 | $12 |
Common stock, no par value | ' | ' |
Common stock, shares authorized | 45 | 45 |
Common stock, shares outstanding | 25.5 | 25.5 |
Consolidated_Statement_of_Cash
Consolidated Statement of Cash Flows (USD $) | 9 Months Ended | |||||||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | ||
Union Electric Company | Union Electric Company | Ameren Illinois Company | Ameren Illinois Company | |||||
Cash Flows From Operating Activities: | ' | ' | ' | ' | ' | ' | ||
Net income | $257 | $181 | $365 | $403 | $141 | $132 | ||
Loss from discontinued operations, net of taxes | 212 | 331 | ' | ' | ' | ' | ||
Adjustments to reconcile net income to net cash provided by operating activities: | ' | ' | ' | ' | ' | ' | ||
Depreciation and amortization | 500 | 466 | 313 | 303 | 178 | 159 | ||
Amortization of nuclear fuel | 46 | 63 | 46 | 63 | ' | ' | ||
FAC prudence review charge | ' | ' | 26 | ' | ' | ' | ||
Amortization of debt issuance costs and premium/discounts | 18 | 13 | 6 | 5 | 11 | 7 | ||
Deferred income taxes and investment tax credits, net | 258 | 249 | 62 | 217 | 120 | 127 | ||
Allowance for equity funds used during construction | -26 | [1] | -26 | [1] | -22 | -23 | ' | ' |
Stock-based compensation costs | 19 | 23 | ' | ' | ' | ' | ||
Other | 14 | -6 | 1 | 7 | -7 | -8 | ||
Changes in assets and liabilities: | ' | ' | ' | ' | ' | ' | ||
Receivables | -88 | -21 | -148 | -62 | 66 | 58 | ||
Materials and supplies | 7 | -57 | 27 | -53 | -20 | -6 | ||
Accounts and wages payable | -102 | -157 | -124 | -168 | 31 | -4 | ||
Taxes accrued | 104 | 95 | 260 | 59 | -2 | -3 | ||
Assets, other | 20 | -24 | 59 | -29 | -33 | -2 | ||
Liabilities, other | -24 | 61 | -78 | 22 | 1 | 42 | ||
Pension and other postretirement benefits | -34 | 16 | -12 | 17 | -13 | -8 | ||
Counterparty collateral, net | 34 | 21 | ' | ' | 34 | 23 | ||
Premiums paid on long-term debt repurchases | ' | -138 | ' | -62 | ' | -76 | ||
Net cash provided by operating activities - continuing operations | 1,215 | 1,090 | ' | ' | ' | ' | ||
Net cash provided by operating activities - discontinued operations | 99 | 222 | ' | ' | ' | ' | ||
Net cash provided by operating activities | 1,314 | 1,312 | 781 | 699 | 507 | 441 | ||
Cash Flows From Investing Activities: | ' | ' | ' | ' | ' | ' | ||
Capital expenditures | -943 | -762 | -480 | -445 | -462 | -309 | ||
Nuclear fuel expenditures | -34 | -56 | -34 | -56 | ' | ' | ||
Money pool advances, net | ' | ' | 24 | ' | ' | ' | ||
Purchases of securities - nuclear decommissioning trust fund | -147 | -341 | -147 | -341 | ' | ' | ||
Sales and maturities of securities - nuclear decommissioning trust fund | 134 | 326 | 134 | 326 | ' | ' | ||
Other | -1 | -6 | -3 | -5 | 6 | 5 | ||
Net cash used in investing activities - continuing operations | -991 | -839 | ' | ' | ' | ' | ||
Net cash used in investing activities - discontinued operations | -42 | -123 | ' | ' | ' | ' | ||
Net cash used in investing activities | -1,033 | -962 | -506 | -521 | -456 | -304 | ||
Cash Flows From Financing Activities: | ' | ' | ' | ' | ' | ' | ||
Dividends on common stock | -291 | -284 | -320 | -300 | -45 | -132 | ||
Dividends paid to noncontrolling interest holders | -5 | -5 | ' | ' | ' | ' | ||
Dividends on preferred stock | ' | ' | -3 | -3 | -2 | -2 | ||
Money pool borrowings, net | ' | ' | ' | ' | -3 | ' | ||
Short-term debt, net | ' | -143 | ' | ' | ' | ' | ||
Redemptions, repurchases and maturities of long-term debt | ' | -754 | ' | -422 | ' | -332 | ||
Issuances of long-term debt | ' | 882 | ' | 482 | ' | 400 | ||
Capital issuance costs | ' | -7 | ' | -4 | ' | -3 | ||
Other | ' | 4 | ' | ' | ' | 4 | ||
Net cash used in financing activities - continuing operations | -296 | -307 | ' | ' | ' | ' | ||
Net cash used in financing activities - discontinued operations | ' | ' | ' | ' | ' | ' | ||
Net cash used in financing activities | -296 | -307 | -323 | -247 | -50 | -65 | ||
Net change in cash and cash equivalents | -15 | 43 | -48 | -69 | 1 | 72 | ||
Cash and cash equivalents at beginning of period | 209 | 255 | ' | ' | ' | ' | ||
Cash and cash equivalents at end of period | 194 | 298 | ' | ' | ' | ' | ||
Less cash and cash equivalents at end of period, discontinued operations | 25 | 25 | ' | ' | ' | ' | ||
Cash and cash equivalents at beginning of period | 184 | ' | 148 | 201 | ' | 21 | ||
Cash and cash equivalents at end of period, continuing operations | 169 | 273 | 100 | 132 | 1 | 93 | ||
Noncash financing activity - dividends on common stock | ' | ($7) | ' | ' | ' | ' | ||
[1] | Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations. |
Summary_Of_Significant_Account
Summary Of Significant Accounting Policies | 9 Months Ended | ||||||||||||||||
Sep. 30, 2013 | |||||||||||||||||
Accounting Policies [Abstract] | ' | ||||||||||||||||
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES | ' | ||||||||||||||||
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES | |||||||||||||||||
General | |||||||||||||||||
Ameren, headquartered in St. Louis, Missouri, is a public utility holding company under PUHCA 2005, administered by FERC. Ameren’s primary assets are its equity interests in its subsidiaries. Ameren’s subsidiaries are separate, independent legal entities with separate businesses, assets, and liabilities. These subsidiaries operate, as the case may be, rate-regulated electric generation, transmission and distribution businesses, rate-regulated natural gas transmission and distribution businesses, and merchant electric generation businesses. Dividends on Ameren’s common stock and the payment of expenses by Ameren depend on distributions made to it by its subsidiaries. Ameren’s principal subsidiaries are listed below. Also see the Glossary of Terms and Abbreviations at the front of this report and in the Form 10-K. | |||||||||||||||||
• | Union Electric Company, doing business as Ameren Missouri, operates a rate-regulated electric generation, transmission and distribution business, and a rate-regulated natural gas transmission and distribution business in Missouri. | ||||||||||||||||
• | Ameren Illinois Company, doing business as Ameren Illinois, operates a rate-regulated electric and natural gas transmission and distribution business in Illinois. | ||||||||||||||||
• | AER consists of non-rate-regulated operations, including Genco, AERG, and Marketing Company, and, through Genco, an 80% ownership interest in EEI, which Ameren consolidates for financial reporting purposes. | ||||||||||||||||
Ameren has various other subsidiaries responsible for activities such as the provision of shared services. Ameren also has a subsidiary, ATXI, that operates a FERC rate-regulated electric transmission business. | |||||||||||||||||
On March 14, 2013, Ameren entered into a transaction agreement to divest New AER to IPH, which Ameren expects will close during the fourth quarter of 2013. Immediately prior to Ameren’s entry into the transaction agreement with IPH, on March 14, 2013, Genco exercised its option under the amended put option agreement with Medina Valley and received an initial payment of $100 million with respect to the sale of its Elgin, Gibson City, and Grand Tower gas-fired energy centers to Medina Valley. On October 11, 2013, Ameren received FERC approval for the divestiture of New AER to IPH and Genco’s sale of the Elgin, Gibson City, and Grand Tower gas-fired energy centers to Medina Valley. Immediately after receipt of FERC approval, Genco completed its sale of these gas-fired energy centers to Medina Valley and received additional cash proceeds of $37.5 million. Medina Valley has entered into an agreement to sell the Elgin, Gibson City, and Grand Tower gas-fired energy centers to Rockland Capital. Ameren expects this third-party sale of these gas-fired energy centers to close by the end of 2013, subject to FERC and other regulatory approvals. See Note 2 - Divestiture Transactions and Discontinued Operations for additional information regarding these divestitures. | |||||||||||||||||
As a result of the transaction agreement with IPH and Ameren’s plan to sell its Elgin, Gibson City, and Grand Tower gas-fired energy centers, Ameren determined that New AER and the Elgin, Gibson City, and Grand Tower gas-fired energy centers qualified for discontinued operations presentation beginning March 14, 2013. Therefore, Ameren has segregated New AER’s and the Elgin, Gibson City, and Grand Tower gas-fired energy centers’ operating results, assets, and liabilities and presented them separately as discontinued operations for all periods presented in this report. Unless otherwise stated, these notes to Ameren’s financial statements exclude discontinued operations for all periods presented. See Note 2 - Divestiture Transactions and Discontinued Operations for additional information regarding that presentation. | |||||||||||||||||
The financial statements of Ameren are prepared on a consolidated basis. Ameren Missouri and Ameren Illinois have no subsidiaries, and therefore their financial statements are not prepared on a consolidated basis. All significant intercompany transactions have been eliminated. All tabular dollar amounts are in millions, unless otherwise indicated. | |||||||||||||||||
Our accounting policies conform to GAAP. Our financial statements reflect all adjustments (which include normal, recurring adjustments) that are necessary, in our opinion, for a fair presentation of our results. The preparation of financial statements in conformity with GAAP requires management to make certain estimates and assumptions. Such estimates and assumptions affect reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the dates of financial statements, and the reported amounts of revenues and expenses during the reported periods. Actual results could differ from those estimates. The results of operations of an interim period may not give a true indication of results that may be expected for a full year. These financial statements should be read in conjunction with the financial statements and the notes thereto included in the Form 10-K. | |||||||||||||||||
During preparation of the 2012 annual statements of cash flows, it was identified that Ameren’s and Ameren Missouri’s 2012 interim statements of cash flows incorrectly classified certain activity from the nuclear decommissioning trust fund. Although not material, operating cash flows were overstated by $49 million for the nine months ended September 30, 2012. The overstated operating cash flows resulted in the investing cash flows being understated by the same amounts. The cash flows for the nine months ended September 30, 2012, for Ameren and Ameren Missouri have been revised in this report to correct for this error. | |||||||||||||||||
Earnings Per Share | |||||||||||||||||
Basic earnings per share is computed by dividing net income attributable to Ameren Corporation common stockholders by the weighted-average number of common shares outstanding during the period. Diluted earnings per share is computed by dividing net income attributable to common stockholders by the diluted weighted-average number of common shares outstanding during the period. Diluted earnings per share reflects the potential dilution that would occur if certain stock-based performance share units were settled. | |||||||||||||||||
The following table presents Ameren’s basic and diluted earnings per share calculations and reconciles the weighted-average number of common shares outstanding to the diluted weighted-average number of common shares outstanding for the three and nine months ended September 30, 2013, and 2012: | |||||||||||||||||
Three Months | Nine Months | ||||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||||
Net income (loss) attributable to Ameren Corporation: | |||||||||||||||||
Continuing operations | $ | 305 | $ | 309 | $ | 464 | $ | 507 | |||||||||
Discontinued operations | (3 | ) | 65 | (212 | ) | (325 | ) | ||||||||||
Net income (loss) attributable to Ameren Corporation | $ | 302 | $ | 374 | $ | 252 | $ | 182 | |||||||||
Average common shares outstanding - basic | 242.6 | 242.6 | 242.6 | 242.6 | |||||||||||||
Assumed settlement of performance share units | 2.5 | 0.3 | 1.8 | 0.3 | |||||||||||||
Average common shares outstanding - diluted | 245.1 | 242.9 | 244.4 | 242.9 | |||||||||||||
Earnings (loss) per common share – basic: | |||||||||||||||||
Continuing operations | $ | 1.26 | $ | 1.28 | $ | 1.92 | $ | 2.09 | |||||||||
Discontinued operations | (0.01 | ) | 0.26 | (0.88 | ) | (1.34 | ) | ||||||||||
Earnings (loss) per common share – basic | $ | 1.25 | $ | 1.54 | $ | 1.04 | $ | 0.75 | |||||||||
Earnings (loss) per common share – diluted: | |||||||||||||||||
Continuing operations | $ | 1.25 | $ | 1.28 | $ | 1.91 | $ | 2.09 | |||||||||
Discontinued operations | (0.01 | ) | 0.26 | (0.88 | ) | (1.34 | ) | ||||||||||
Earnings (loss) per common share – diluted | $ | 1.24 | $ | 1.54 | $ | 1.03 | $ | 0.75 | |||||||||
Average performance share units excluded from calculation(a) | — | 1 | 0.1 | 1 | |||||||||||||
(a) | Weighted-average number of performance share units that were excluded from the “Assumed settlement of performance share units” provided above because the performance or market conditions related to the awards had not yet been met. | ||||||||||||||||
Stock-based Compensation | |||||||||||||||||
A summary of nonvested performance share units at September 30, 2013, and changes during the nine months ended September 30, 2013, under the 2006 Omnibus Incentive Compensation Plan (2006 Plan) are presented below: | |||||||||||||||||
Performance Share Units | |||||||||||||||||
Share Units | Weighted-average Fair Value Per Unit at Grant Date | ||||||||||||||||
Nonvested as of January 1, 2013 | 1,192,487 | $ | 33.56 | ||||||||||||||
Granted(a) | 837,199 | 31.19 | |||||||||||||||
Forfeitures | (7,757 | ) | 32.66 | ||||||||||||||
Vested(b) | (131,960 | ) | 31.3 | ||||||||||||||
Nonvested as of September 30, 2013 | 1,889,969 | $ | 32.67 | ||||||||||||||
(a) | Includes performance share units (share units) granted to certain executive and nonexecutive officers and other eligible employees in 2013 under the 2006 Plan. | ||||||||||||||||
(b) | Share units vested due to the attainment of retirement eligibility by certain employees. Actual shares issued for retirement-eligible employees will vary depending on actual performance over the three-year measurement period. | ||||||||||||||||
The fair value of each share unit awarded in 2013 under the 2006 Plan was determined to be $31.19. That amount was based on Ameren’s closing common share price of $30.72 at December 31, 2012, and lattice simulations. Lattice simulations are used to estimate expected share payout based on Ameren’s total stockholder return for a three-year performance period relative to the designated peer group beginning January 1, 2013. The simulations can produce a greater fair value for the share unit than the applicable closing common share price because they include the weighted payout scenarios in which an increase in the share price has occurred. The significant assumptions used to calculate fair value also included a three-year risk-free rate of 0.36%, volatility of 12% to 21% for the peer group, and Ameren’s attainment of a three-year average earnings per share threshold during the performance period. | |||||||||||||||||
Intangible Assets | |||||||||||||||||
Ameren and Ameren Missouri classify emission allowances and renewable energy credits as intangible assets. Ameren Illinois consumes renewable energy credits as they are purchased through the IPA procurement process and expenses them immediately. We evaluate intangible assets for impairment if events or changes in circumstances indicate that their carrying amount might be impaired. | |||||||||||||||||
At September 30, 2013, Ameren’s and Ameren Missouri’s intangible assets consisted of renewable energy credits obtained through wind and solar power purchase agreements. The book value of Ameren’s and Ameren Missouri’s renewable energy credits was $19 million and $19 million, respectively, at September 30, 2013. The book value of Ameren’s and Ameren Missouri’s renewable energy credits was $14 million and $14 million, respectively, at December 31, 2012. | |||||||||||||||||
Renewable energy credits and emission allowances are charged to purchased power expense and fuel expense, respectively, as they are used in operations. In accordance with the MoPSC's 2012 electric rate order, the majority of Ameren Missouri's amortization of intangible assets is deferred as a regulatory asset pending future recovery from customers through rates. The following table presents amortization expense based on usage of renewable energy credits and emission allowances, net of gains from sales, for Ameren, Ameren Missouri, and Ameren Illinois, during the three and nine months ended September 30, 2013, and 2012. | |||||||||||||||||
Three Months | Nine Months | ||||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||||
Ameren Missouri | $ | — | $ | 1 | $ | (a) | $ | 1 | |||||||||
Ameren Illinois | 2 | 1 | 9 | 1 | |||||||||||||
Ameren | $ | 2 | $ | 2 | $ | 9 | $ | 2 | |||||||||
(a) | Less than $1 million. | ||||||||||||||||
Excise Taxes | |||||||||||||||||
Excise taxes levied on us are reflected on Ameren Missouri electric customer bills and on Ameren Missouri and Ameren Illinois natural gas customer bills. They are recorded gross in “Operating Revenues - Electric,” “Operating Revenues - Gas” and “Operating Expenses - Taxes other than income taxes” on the statement of income or the statement of income and comprehensive income. Excise taxes reflected on Ameren Illinois electric customer bills are imposed on the consumer and are therefore not included in revenues and expenses. They are recorded as tax collections payable and included in “Taxes accrued” on the balance sheet. The following table presents excise taxes recorded in “Operating Revenues - Electric,” “Operating Revenues - Gas” and “Operating Expenses - Taxes other than income taxes” for the three and nine months ended September 30, 2013, and 2012: | |||||||||||||||||
Three Months | Nine Months | ||||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||||
Ameren Missouri | $ | 49 | $ | 46 | $ | 120 | $ | 111 | |||||||||
Ameren Illinois | 10 | 9 | 43 | 37 | |||||||||||||
Ameren | $ | 59 | $ | 55 | $ | 163 | $ | 148 | |||||||||
Uncertain Tax Positions | |||||||||||||||||
The amount of unrecognized tax benefits (detriments) as of September 30, 2013, was $86 million, $27 million, and $(2) million, for Ameren, Ameren Missouri, and Ameren Illinois, respectively. Unrecognized tax benefits are included in “Other deferred credits and liabilities” on Ameren’s, Ameren Missouri’s, and Ameren Illinois’ September 30, 2013 balance sheets. The amount of unrecognized tax benefits (detriments) as of September 30, 2013, that would impact the effective tax rate, if recognized, was $51 million, $2 million, and $(1) million for Ameren, Ameren Missouri, and Ameren Illinois, respectively. The Ameren amount of unrecognized tax benefits that would impact the effective tax rate, if recognized, increased by $50 million primarily during the first quarter of 2013. This increase was primarily due to uncertainty related to the historical computation of Ameren’s tax basis in its stock investment in AER. | |||||||||||||||||
During the three months ended September 30, 2013, unrecognized tax benefits related to the deductibility of expenditures to maintain, replace, or improve steam or electric power generation property, along with casualty loss deductions for storm damage, were reduced by $113 million, $103 million, and $5 million, for Ameren, Ameren Missouri, and Ameren Illinois, respectively, with an offset to “Accumulated deferred income taxes, net.” This was the result of recent Internal Revenue Service guidance establishing new rules for the amount and timing of these deductions. | |||||||||||||||||
Ameren’s federal income tax returns for the years 2007 through 2011 are before the Appeals Office of the Internal Revenue Service. Ameren’s federal income tax return for the year 2012 is currently under examination. | |||||||||||||||||
It is reasonably possible that a settlement will be reached with the Appeals Office of the Internal Revenue Service in the next 12 months for the years 2007 through 2011. This settlement, which is primarily related to uncertain tax positions for research tax deductions, is expected to result in a decrease in uncertain tax benefits of $23 million, $15 million, and $- million for Ameren, Ameren Missouri, and Ameren Illinois, respectively. In addition, it is reasonably possible that other events will occur during the next 12 months that would cause the total amount of unrecognized tax benefits for the Ameren Companies to increase or decrease. However, the Ameren Companies do not believe any such increases or decreases, including the decrease from the reasonably possible Internal Revenue Service Appeals Office settlement discussed above, would be material to their results of operations, financial position, or liquidity. | |||||||||||||||||
State income tax returns are generally subject to examination for a period of three years after filing of the return. The Ameren Companies do not currently have material state income tax issues under examination, administrative appeals, or litigation. The state impact of any federal changes remains subject to examination by various states for a period of up to one year after formal notification to the states. | |||||||||||||||||
Ameren Missouri has an uncertain tax position tracker. Under Missouri’s regulatory framework, uncertain income tax positions do not reduce Ameren Missouri’s electric rate base. When an uncertain income tax position liability is resolved, the MoPSC requires, through the uncertain tax position tracker, the creation of a regulatory asset or regulatory liability to reflect the time value (using the weighted-average cost of capital included in each of the electric rate orders in effect before the tax position was resolved) of the difference between the uncertain income tax position liability that was excluded from rate base and the final tax liability. The resulting regulatory asset or liability will be amortized over three years beginning on the effective date of new rates established in the next electric rate case. | |||||||||||||||||
Asset Retirement Obligations | |||||||||||||||||
The following table provides a reconciliation of the beginning balance and ending carrying amount of AROs for the nine months ended September 30, 2013: | |||||||||||||||||
Ameren | Ameren | Other(c) | Ameren(a) | ||||||||||||||
Missouri(a) | Illinois(b) | ||||||||||||||||
Balance at December 31, 2012 | $ | 346 | $ | 3 | $ | 26 | $ | 375 | |||||||||
Liabilities incurred | — | — | — | — | |||||||||||||
Liabilities settled | (d) | (d) | (d) | (d) | |||||||||||||
Accretion in 2013(e) | 14 | (d) | 1 | 15 | |||||||||||||
Change in estimates(f) | 2 | (d) | (d) | 2 | |||||||||||||
Balance at September 30, 2013 | $ | 362 | $ | 3 | $ | 27 | $ | 392 | |||||||||
(a) | The nuclear decommissioning trust fund assets of $459 million and $408 million as of September 30, 2013, and December 31, 2012, respectively, were restricted for decommissioning of the Callaway energy center. | ||||||||||||||||
(b) | Balance included in “Other deferred credits and liabilities” on the balance sheet. | ||||||||||||||||
(c) | Represents amounts for the Meredosia and Hutsonville energy centers. Pursuant to the transaction agreement to divest New AER to IPH, Ameren will retain the AROs associated with the Meredosia and Hutsonville energy centers. See Note 2 - Divestiture Transactions and Discontinued Operations for additional information. | ||||||||||||||||
(d) | Less than $1 million. | ||||||||||||||||
(e) | Accretion was recorded as an increase to regulatory assets at Ameren Missouri and Ameren Illinois. | ||||||||||||||||
(f) | Ameren Missouri changed its fair value estimates for asbestos removal and certain CCR storage facilities. | ||||||||||||||||
Noncontrolling Interest | |||||||||||||||||
Ameren's noncontrolling interests comprised the 20% of EEI not owned by Ameren and the preferred stock not subject to mandatory redemption of Ameren's subsidiaries. These noncontrolling interests were classified as a component of equity separate from Ameren's equity on its consolidated balance sheet. A reconciliation of the equity changes attributable to the noncontrolling interests at Ameren for the three and nine months ended September 30, 2013, and 2012, is shown below: | |||||||||||||||||
Three Months | Nine Months | ||||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||||
Noncontrolling interests, beginning of period (a) | $ | 151 | $ | 145 | $ | 151 | $ | 149 | |||||||||
Net income from continuing operations attributable to noncontrolling interests | 2 | 2 | 5 | 5 | |||||||||||||
Net loss from discontinued operations attributable to noncontrolling interests | — | (2 | ) | — | (6 | ) | |||||||||||
Dividends paid to noncontrolling interest holders | (2 | ) | (2 | ) | (5 | ) | (5 | ) | |||||||||
Other comprehensive income attributable to noncontrolling interests(b) | — | 9 | — | 9 | |||||||||||||
Noncontrolling interests, end of period (a) | $ | 151 | $ | 152 | $ | 151 | $ | 152 | |||||||||
(a) | Includes the 20% EEI ownership interest not owned by Ameren. The assets and liabilities of EEI were consolidated in Ameren’s balance sheet at a 100% ownership level and were included in “Current assets of discontinued operations” and “Current liabilities of discontinued operations.” The 20% ownership interest not owned by Ameren was included in “Noncontrolling interests” on Ameren’s September 30, 2013, and December 31, 2012 balance sheets. See Note 2 - Divestiture Transactions and Discontinued Operations for additional information. | ||||||||||||||||
(b) | Represents the noncontrolling interest of EEI’s pension and other postretirement benefit plan activity, net of income taxes of $-, $6, $-, and $6, respectively. | ||||||||||||||||
Accounting and Reporting Developments | |||||||||||||||||
The following is a summary of recently adopted authoritative accounting guidance, as well as guidance issued but not yet adopted, that could impact the Ameren Companies. | |||||||||||||||||
Presentation of Comprehensive Income | |||||||||||||||||
In June 2011, FASB amended its guidance on the presentation of comprehensive income in financial statements. The amended guidance changed the presentation of comprehensive income in the financial statements. It requires entities to report components of comprehensive income either in a continuous statement of comprehensive income or in two separate but consecutive statements. This guidance was effective for the Ameren Companies beginning in the first quarter of 2012 with retroactive application required. The implementation of the amended guidance did not affect the Ameren Companies’ results of operations, financial position, or liquidity. | |||||||||||||||||
In February 2013, FASB amended this guidance to require an entity to provide information about the amounts reclassified out of accumulated OCI by component. In addition, an entity is required to present significant amounts reclassified out of accumulated OCI by the respective line items of net income either on the face of the statement where net income is presented or in the footnotes. This guidance was effective for the Ameren Companies beginning in the first quarter of 2013. The implementation of this amended guidance did not affect the Ameren Companies’ results of operations, financial position, or liquidity. The only amounts reclassified out of accumulated OCI for the Ameren Companies related to pension and other postretirement plan activity and derivatives. These amounts were immaterial for the three and nine months ended September 30, 2013, and therefore no additional disclosures were required. | |||||||||||||||||
Disclosures about Offsetting Assets and Liabilities | |||||||||||||||||
In December 2011, FASB issued additional authoritative accounting guidance to improve information disclosed about financial and derivative instruments. The guidance requires an entity to disclose information about offsetting and related arrangements to enable users of the financial statements to understand the effect of those arrangements on its financial position. In January 2013, FASB amended this guidance to limit the scope to derivative instruments, repurchase agreements and reverse repurchase agreements, and securities borrowing and securities lending transactions. The Ameren Companies adopted this guidance for the first quarter of 2013. The implementation of this additional guidance did not affect the Ameren Companies’ results of operations, financial positions, or liquidity, as this guidance only requires additional disclosures. See Note 7 - Derivative Financial Instruments for the required additional disclosures. | |||||||||||||||||
Presentation of an Unrecognized Tax Benefit | |||||||||||||||||
In July 2013, FASB issued additional authoritative accounting guidance to provide clarity for the financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists. The objective of this guidance is to eliminate diversity in practice related to the presentation of certain unrecognized tax benefits. It requires entities to present an unrecognized tax benefit as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward to the extent a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is available under the tax law. Currently, any unrecognized tax benefit is recorded in “Other deferred credits and liabilities” on Ameren's, Ameren Missouri's, and Ameren Illinois' balance sheets. After this guidance becomes effective, any unrecognized tax benefit will be recorded in “Accumulated deferred income taxes, net” as a reduction to the deferred tax assets for net operating loss and tax credit carryforwards on the respective balance sheets. To the extent that an unrecognized tax benefit exceeds these carryforwards, the excess would continue to be recorded in “Other deferred credits and liabilities,” on the respective balance sheets, consistent with current authoritative accounting guidance. The amended guidance will not affect the Ameren Companies' results of operations or liquidity, as this guidance is presentation-related only. This guidance will be effective for the Ameren Companies beginning in the first quarter of 2014. |
Divestiture_Transactions_and_D
Divestiture Transactions and Discontinued Operations (Notes) | 9 Months Ended | ||||||||||||||||
Sep. 30, 2013 | |||||||||||||||||
Discontinued Operations and Disposal Groups [Abstract] | ' | ||||||||||||||||
DIVESTITURE TRANSACTIONS AND DISCONTINUED OPERATIONS | ' | ||||||||||||||||
DIVESTITURE TRANSACTIONS AND DISCONTINUED OPERATIONS | |||||||||||||||||
Transaction Agreement with IPH | |||||||||||||||||
On March 14, 2013, Ameren entered into a transaction agreement to divest New AER to IPH. Under the terms of the transaction agreement, AER will effect a reorganization that will, among other things, transfer substantially all of the assets and liabilities of AER, other than (i) any outstanding debt obligations of AER to Ameren or its other subsidiaries, except for certain intercompany balances discussed below, (ii) all of the issued and outstanding equity interests in Medina Valley, (iii) the assets and liabilities associated with Genco’s Meredosia, Hutsonville, Elgin, Gibson City, and Grand Tower gas-fired energy centers, (iv) the obligations relating to Ameren's single-employer pension and postretirement benefit plans, and (v) the deferred tax positions associated with Ameren's ownership of these retained assets and liabilities, to New AER. IPH will acquire all of the equity interests in New AER. | |||||||||||||||||
Ameren will retain the pension and postretirement benefit obligations associated with current and former employees of AER that are included in the Ameren Retirement Plan, the Ameren Supplemental Retirement Plan, the Ameren Retiree Medical Plan, and the Ameren Group Life Insurance Plan. This noncurrent obligation is reflected on Ameren’s consolidated balance sheet as “Pension and other postretirement benefits.” IPH will assume the pension and other postretirement benefit obligations associated with EEI’s current and former employees that are included in the Revised Retirement Plan for Employees of Electric Energy, Inc., the Group Insurance Plan for Management Employees of Electric Energy, Inc., and the Group Insurance Plan for Bargaining Unit Employees of Electric Energy, Inc. The obligations to be assumed by IPH are estimated at $32 million at September 30, 2013. IPH will also acquire the estimated $15 million asset at September 30, 2013, relating to the overfunded status of one of EEI’s postretirement plans. | |||||||||||||||||
Ameren will retain Genco’s Meredosia and Hutsonville energy centers, which are idle and had an immaterial property and plant asset balance as of September 30, 2013. Ameren will also retain AROs associated with these energy centers, estimated at $27 million as of September 30, 2013. The Meredosia and Hutsonville energy centers are currently included in continuing operations; however, Ameren is evaluating whether it would be appropriate to classify them as abandoned and discontinued coincident with closing of the transaction with IPH. All other AROs associated with AER are expected to be assumed by either New AER or the third-party buyer of the Grand Tower energy center. | |||||||||||||||||
Upon the transaction agreement closing, with the exception of certain agreements, such as supply obligations to Ameren Illinois, a note from New AER to Ameren relating to cash collateral that will remain outstanding at closing, and Genco money pool advances, all intercompany agreements and debt between AER and its subsidiaries, on the one hand, and Ameren and its non-AER affiliates, on the other hand, will be either retained or cancelled by Ameren, without any cost or obligation to IPH or New AER and its subsidiaries. Immediately prior to the transaction agreement closing, the cash collateral provided to New AER by Ameren through money pool borrowings will be converted to a note payable to Ameren, which will be payable, with interest, 24 months after closing or sooner as cash collateral requirements are reduced. Cash collateral postings by AER and its subsidiaries with external parties, including postings related to exchange-traded contracts, at September 30, 2013, were $27 million. | |||||||||||||||||
Genco's $825 million in aggregate principal amount of senior notes will remain outstanding following the closing of the transaction agreement and will continue to be solely obligations of Genco. Pursuant to the transaction agreement, in addition to the cash paid to Genco for the Elgin, Gibson City, and Grand Tower energy center sale, Ameren will cause $85 million of cash to be retained at New AER. | |||||||||||||||||
As a condition to the transaction agreement, Genco exercised the amended put option agreement for the sale of the Elgin, Gibson City, and Grand Tower gas-fired energy centers to Medina Valley. In October 2013, immediately after receipt of FERC approval, Genco completed the sale of the Elgin, Gibson City, and Grand Tower gas-fired energy centers to Medina Valley. | |||||||||||||||||
Completion of the divestiture of New AER to IPH requires FERC and FCC approvals. In October 2013, FERC issued an order approving the divestiture of New AER. The FCC approval was received in August 2013. Separately, as a condition to IPH’s obligation to complete the New AER transaction, the Illinois Pollution Control Board must approve the transfer to IPH of, or otherwise approve a variance in favor of IPH on the same material terms as, AER’s variance of the Illinois MPS. In May 2013, AER and IPH filed a transfer request with the Illinois Pollution Control Board, which was subsequently denied by the board on procedural grounds. On July 22, 2013, IPH, AER, and Medina Valley, as current and future owners of the coal-fired energy centers, filed a request for a variance with the Illinois Pollution Control Board seeking materially the same relief as the existing AER variance. The Illinois Pollution Control Board has until late November 2013 to issue a decision. See Note 10 - Commitments and Contingencies for additional information. Ameren’s and IPH’s obligation to complete the transaction is also subject to other customary closing conditions, including the material accuracy of each company’s representations and warranties and the compliance, in all material respects, with each company’s covenants. The transaction agreement contains customary representations and warranties of Ameren and IPH, including representations and warranties of Ameren with respect to the business being sold. The transaction agreement also contains customary covenants of Ameren and IPH, including the covenant of Ameren that AER will be operated in the ordinary course prior to the closing. | |||||||||||||||||
Ameren expects the closing of the New AER divestiture to IPH will occur in the fourth quarter of 2013. If the closing does not occur on or before March 14, 2014, either party may elect to terminate the transaction agreement if the inability to close the transaction by such date is not the result of the failure of the terminating company to fulfill any of its obligations under the transaction agreement. The transaction agreement with IPH also provides for a $25 million cash termination fee if either Ameren or IPH breach any of their representations, warranties, covenants or obligations in a manner that would result in the other party having the right to terminate the transaction agreement, or if Ameren or IPH fails to complete the transaction within three business days of the scheduled closing date, subject to certain exceptions. | |||||||||||||||||
Amended Put Option Agreement, Asset Purchase Agreement and Guaranty | |||||||||||||||||
Prior to entry into the transaction agreement with IPH as discussed above, (i) the original put option agreement between Genco and AERG was novated and amended such that the rights and obligations of AERG under the agreement were assigned to and assumed by Medina Valley and (ii) Genco exercised its option under the amended put option agreement to sell the Elgin, Gibson City, and Grand Tower gas-fired energy centers to Medina Valley. As a result, on March 14, 2013, Genco received an initial payment of $100 million in accordance with the terms of the amended put option agreement. Genco advanced the initial payment amount it received into the non-state-regulated subsidiary money pool. In connection with the amended put option agreement, Ameren's guaranty, dated March 28, 2012, was modified to replace all references to AERG with references to Medina Valley. | |||||||||||||||||
Pursuant to the amended put option agreement, Genco and Medina Valley entered into an asset purchase agreement, dated March 14, 2013. The asset purchase agreement provided that Genco would receive an additional payment upon closing of the asset purchase agreement to the extent the average fair market value for the Elgin, Gibson City, and Grand Tower gas-fired energy centers, as determined based on three independent appraisals, exceeded the $100 million initial payment Genco received from Medina Valley. Genco and Medina Valley engaged three independent appraisers to conduct fair market valuations of the Elgin, Gibson City, and Grand Tower gas-fired energy centers. The average fair market value pursuant to such appraisals for the Elgin, Gibson City, and Grand Tower gas-fired energy centers was $137.5 million, which was greater than the original fair value estimate of $133 million. Therefore, after receipt of FERC approval and upon closing of the asset purchase agreement in October 2013, Genco received an additional payment of $37.5 million from Medina Valley. Genco advanced the additional $37.5 million it received into the non-state-regulated subsidiary money pool. | |||||||||||||||||
The transaction agreement with IPH provides that if the Elgin, Gibson City, and Grand Tower gas-fired energy centers are subsequently sold to a third-party and Medina Valley receives proceeds within two years of the closing of the New AER divestiture, Medina Valley will pay Genco any proceeds from such sale, net of taxes and other expenses, in excess of the amounts previously paid to Genco, which totaled $137.5 million. | |||||||||||||||||
Medina Valley has entered into an agreement to sell the Elgin, Gibson City, and Grand Tower gas-fired energy centers to Rockland Capital. This agreement requires a portion of the purchase price to be held in escrow until the two year anniversary of the closing of the sale to fund certain indemnity obligations, if any, of Medina Valley. Ameren expects the sale of the Elgin, Gibson City, and Grand Tower gas-fired energy centers to Rockland Capital to close by the end of 2013, subject to receipt of FERC and other regulatory approvals. If this sale is completed, Medina Valley could pay Genco after-tax net proceeds of up to an additional $15 million based on the maximum escrow amount that could ultimately be released, projected working capital adjustments, and projected transaction expenses. | |||||||||||||||||
In August 2013, the Illinois Municipal Electric Agency, which is a wholesale customer of Marketing Company, filed a lawsuit in the United States District Court for the Central District of Illinois against Marketing Company alleging that the removal of certain assets that were related to the amended put option agreement from the parties’ contract schedules without the customer’s consent constituted a breach of contract. In addition, the lawsuit alleges that Genco and AERG failed to recognize certain asset impairments that the Illinois Municipal Electric Agency alleges have occurred and which the Illinois Municipal Electric Agency claims would, if recognized, reduce the billings to the Illinois Municipal Electric Agency. The lawsuit also makes certain other claims that the proposed divestiture would result in a breach of the parties’ contract. Marketing Company believes its defenses to these allegations are meritorious and will defend itself vigorously. | |||||||||||||||||
Discontinued Operations Presentation | |||||||||||||||||
As of March 14, 2013, Ameren determined that New AER and the Elgin, Gibson City, and Grand Tower gas-fired energy centers qualified for discontinued operations presentation and, therefore, were classified separately in Ameren’s consolidated financial statements as discontinued operations for all periods presented in this report. Ameren concluded that New AER and collectively the Elgin, Gibson City, and Grand Tower gas-fired energy centers are two separate disposal groups. Both disposal groups have been aggregated in the disclosures below. Each disposal group was measured at fair value on a nonrecurring basis with inputs that are classified as Level 3 within the fair value hierarchy. | |||||||||||||||||
The following table presents the components of discontinued operations in Ameren's consolidated statement of income for the three and nine months ended September 30, 2013, and 2012: | |||||||||||||||||
Three Months | Nine months | ||||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||||
Operating revenues | $ | 311 | $ | 293 | $ | 878 | $ | 797 | |||||||||
Operating expenses | (309 | ) | (237 | ) | (1,034 | ) | (a) | (1,301 | ) | (b) | |||||||
Operating income (loss) | 2 | 56 | (156 | ) | (504 | ) | |||||||||||
Other income (loss) | — | — | (1 | ) | — | ||||||||||||
Interest charges | (9 | ) | (14 | ) | (31 | ) | (43 | ) | |||||||||
Income (loss) before income taxes | (7 | ) | 42 | (188 | ) | (547 | ) | ||||||||||
Income tax (expense) benefit | 4 | 21 | (24 | ) | 216 | ||||||||||||
Income (loss) from discontinued operations, net of taxes | $ | (3 | ) | $ | 63 | $ | (212 | ) | $ | (331 | ) | ||||||
(a) | Includes a noncash pretax impairment charge of $175 million for the nine months ended September 30, 2013, to reduce the carrying value of the New AER disposal group to its estimated fair value less cost to sell. | ||||||||||||||||
(b) | Includes a noncash pretax asset impairment charge of $628 million to reduce the carrying value of AERG’s Duck Creek energy center to its estimated fair value under held and used accounting guidance. | ||||||||||||||||
As the New AER disposal group continued to meet the discontinued operations criteria at September 30, 2013, Ameren evaluated whether any impairment existed by comparing the disposal group’s carrying value to the estimated fair value of the disposal group, less cost to sell. The fair value was based on the terms of Ameren’s agreement to divest New AER to IPH. Ameren will receive no cash proceeds from IPH for the divestiture of New AER. Ameren recorded a cumulative pretax charge to earnings of $175 million for the nine months ended September 30, 2013, to reduce the carrying value of the New AER disposal group to its estimated fair value less cost to sell. Ameren recorded a pretax charge to earnings of $7 million for the three months ended September 30, 2013, to reduce the carrying value of the New AER disposal group to its estimated fair value less cost to sell. The pretax charge to earnings increased during the three months ended September 30, 2013, as the disposal group’s carrying value increased, primarily as a result of contributions made to EEI’s pension plan and derivative market value gains. The impairment loss was recorded in “Operating expenses” within the components of the discontinued operations statement of income with a corresponding reduction in “Property and Plant, net” within the components of the discontinued operations balance sheet. Ameren estimated the impairment loss of the disposal group based on the estimated fair value pursuant to the terms of the transaction agreement with IPH, using information currently available, and assuming an expected fourth quarter 2013 closing. Actual operating results, derivative market values, capital expenditures and other items will impact the ultimate loss recognized to reduce the carrying value of the New AER disposal group to its actual fair value less cost to sell, which will be recorded in discontinued operations after all of the information becomes available. In addition, any curtailment gain related to Ameren's pension and postretirement plans will be recorded when the related employees terminate employment with Ameren. The ultimate impairment loss may differ materially from the estimated loss recorded as of September 30, 2013. | |||||||||||||||||
Ameren adjusted accumulated deferred income taxes on its balance sheet to reflect the excess of tax basis over financial reporting basis of its stock investment in AER, during the three months ended March 31, 2013, when it became apparent that the temporary difference would reverse. This change in basis resulted in a discontinued operations deferred tax expense of $96 million, which was partially offset by the expected tax benefits of $72 million related to the pretax loss from discontinued operations including the impairment charge, during the nine months ended September 30, 2013. During the third quarter of 2013, Ameren recorded tax benefits of $3 million related to the incremental pretax loss from discontinued operations recorded during the third quarter of 2013. In addition, Ameren recorded a $1 million reduction in discontinued operations deferred tax expense during the third quarter of 2013 to reflect changes in the estimates of the excess of tax basis over financial reporting basis of Ameren’s stock investment in AER. The final tax basis of the AER disposal group and the related tax benefit resulting from the transaction agreement with IPH are dependent upon taxable losses utilized by the disposal group through the closing and the resolution of tax matters under audit, including the adoption of recently issued guidance from the Internal Revenue Service related to tangible property repairs and other matters. As a result, tax expense and benefits realized in discontinued operations may differ materially from those recorded as of September 30, 2013. | |||||||||||||||||
As the Elgin, Gibson City, and Grand Tower gas-fired energy center disposal group continued to meet the discontinued operations criteria at September 30, 2013, Ameren evaluated whether any impairment existed by comparing the disposal group’s carrying value to the estimated fair value of the disposal group, less cost to sell. The fair value was based on the appraised value of these three gas-fired energy centers. In December 2012, Ameren recorded a noncash long-lived asset impairment charge to reduce the carrying value of AER’s energy centers, including the Elgin, Gibson City, and Grand Tower gas-fired energy centers, to their estimated fair values under the accounting guidance for held and used assets. The December 2012 held and used asset impairment charge reduced these energy centers’ disposal group carrying value to their estimated fair value of $133 million. Ameren will not recognize a gain from the third party sale to Rockland Capital for any value in excess of the $133 million carrying value of this disposal group since any excess amount that Medina Valley may receive, net of taxes and other expenses, over the carrying value, will ultimately be paid to Genco pursuant to the transaction agreement with IPH. Ameren does not expect to have significant continuing involvement or material cash flows with the Elgin, Gibson City, and Grand Tower gas-fired energy centers after their sale. | |||||||||||||||||
Effective with its conclusion that the New AER disposal group and the Elgin, Gibson City, and Grand Tower gas-fired energy centers’ disposal group each met the criteria for held for sale presentation, Ameren suspended recording depreciation on these assets in March 2013. | |||||||||||||||||
Interest on Genco’s senior notes, which will continue to be solely obligations of Genco following the closing of the transaction agreement with IPH, are included in the “Interest charges” component within the discontinued operations line item in the statement of income. Ameren did not allocate corporate interest to the disposal groups. Additionally, general corporate overhead expenses originally allocated to the disposal groups were classified as expenses of continuing operations. | |||||||||||||||||
The following table presents the carrying amounts of the components of assets and liabilities segregated on Ameren's consolidated balance sheets as discontinued operations at September 30, 2013, and December 31, 2012: | |||||||||||||||||
30-Sep-13 | 31-Dec-12 | ||||||||||||||||
Assets of discontinued operations | |||||||||||||||||
Cash and cash equivalents | $ | 25 | $ | 25 | |||||||||||||
Accounts receivable and unbilled revenue | 102 | 102 | |||||||||||||||
Materials and supplies | 121 | 134 | |||||||||||||||
Mark-to-market derivative assets | 71 | 102 | |||||||||||||||
Property and plant, net | 623 | 748 | |||||||||||||||
Accumulated deferred income taxes, net | 357 | 385 | |||||||||||||||
Other assets | 96 | 104 | |||||||||||||||
Total assets of discontinued operations | $ | 1,395 | $ | 1,600 | |||||||||||||
Liabilities of discontinued operations | |||||||||||||||||
Accounts payable and other current obligations | $ | 141 | $ | 133 | |||||||||||||
Mark-to-market derivative liabilities | 38 | 63 | |||||||||||||||
Long-term debt, net | 824 | 824 | |||||||||||||||
Asset retirement obligations | 87 | 78 | |||||||||||||||
Pension and other postretirement benefits | 32 | 40 | |||||||||||||||
Other liabilities | 19 | 28 | |||||||||||||||
Total liabilities of discontinued operations | $ | 1,141 | $ | 1,166 | |||||||||||||
Accumulated other comprehensive income(a) | $ | 3 | $ | 19 | |||||||||||||
Noncontrolling interest(b) | $ | 8 | $ | 8 | |||||||||||||
(a) | Accumulated other comprehensive income related to discontinued operations remains in “Accumulated other comprehensive loss” on Ameren’s September 30, 2013, and December 31, 2012, balance sheets. This balance relates to New AER assets and liabilities that will be realized or removed from Ameren’s balance sheet either before or at the closing of the New AER divestiture. | ||||||||||||||||
(b) | The 20% ownership interest of EEI not owned by Ameren was included in “Noncontrolling interests” on Ameren’s September 30, 2013, and December 31, 2012, balance sheets. This noncontrolling interest will be removed from Ameren’s balance sheet at the closing of the New AER divestiture. | ||||||||||||||||
Ameren will have continuing transactions with New AER after the divestiture is complete. Ameren Illinois has power supply agreements with Marketing Company, which are a result of the power procurement process in Illinois administered by the IPA as required by the Illinois Public Utilities Act. Ameren Illinois will continue to purchase power and purchase trade receivables as required by Illinois law, and Ameren will reflect these items as continuing operations after the divestiture occurs. Ameren Illinois and ATXI currently sell, and will continue to sell, transmission services to Marketing Company after the divestiture of New AER is completed. Also, upon the divestiture of New AER, the transaction agreement requires Ameren (parent) to maintain its financial obligations with respect to all credit support provided to New AER for all transactions entered into prior to the closing of such divestiture for up to 24 months after the closing. IPH shall indemnify Ameren for any payments Ameren makes pursuant to these credit support obligations if the counterparty does not return the posted collateral to Ameren. IPH’s indemnification obligation will be secured by certain AERG and Genco assets. In addition, Dynegy has provided a limited guarantee of $25 million to Ameren (parent) pursuant to which Dynegy will, among other things, guarantee IPH’s indemnification obligations for a period of up to 24 months after the closing (subject to certain exceptions). Immediately prior to the transaction agreement closing, the cash collateral provided to New AER by Ameren through money pool borrowings will be converted to a note payable to Ameren which will be payable, with interest, 24 months after closing or sooner as cash collateral requirements are reduced. Also, within 120 days after closing, a working capital adjustment will be finalized, which may result in a cash payment from Ameren to New AER. Ameren has determined that the continuing cash flows generated by these arrangements are not significant and, accordingly, are not deemed direct cash flows of the divested business. Additionally, these arrangements do not provide Ameren the ability to significantly influence the operating results of New AER after the divestiture is complete. See Note 9 - Related Party Transactions for additional information regarding existing transactions between Ameren and New AER. | |||||||||||||||||
For a period of up to 12 months following the closing, Ameren will provide certain transitional services to IPH. Such services will be provided at no charge for 90 days, subject to a $5 million limit; thereafter, services will be provided at cost, except for certain services that may be applied to the $5 million limit to the extent such limit has not been reached by the end of the 90 day period. The transitional services may be provided for six months after the closing and can be extended by IPH on a month-to-month basis for up to an additional six months. | |||||||||||||||||
See Note 10 - Commitments and Contingencies for information regarding amendments to the plant transfer agreements between both Genco and Ameren Illinois and AERG and Ameren Illinois as well as other AER related matters. | |||||||||||||||||
Genco Indenture Provisions | |||||||||||||||||
Genco’s indenture includes provisions that require Genco to maintain certain interest coverage and debt-to-capital ratios in order for Genco to pay dividends, to make principal or interest payments on subordinated borrowings, to make loans to or investments in affiliates, or to incur additional external, third-party indebtedness. The following table summarizes these ratios for the 12 months ended and as of September 30, 2013: | |||||||||||||||||
Required | Actual | ||||||||||||||||
Ratio | Ratio | ||||||||||||||||
Interest coverage ratio- restricted payment (a) | ≥1.75 | 1.05 | |||||||||||||||
Interest coverage ratio- additional indebtedness (b) | ≥2.50 | 1.05 | |||||||||||||||
Debt-to-capital ratio- additional indebtedness (b) | ≤60% | 51 | % | ||||||||||||||
(a) | As of the date of the restricted payment, as defined, the minimum ratio must have been achieved for the most recently ended four fiscal quarters and projected by management to be achieved for each of the subsequent four six-month periods. Investments in the non-state-regulated subsidiary money pool and repayments of non-state-regulated subsidiary money pool borrowings are not subject to this incurrence test. | ||||||||||||||||
(b) | Ratios must be computed on a pro forma basis considering the additional indebtedness to be incurred and the related interest expense. Non-state-regulated subsidiary money pool borrowings are defined as permitted indebtedness and are not subject to these incurrence tests. Other borrowings from third-party external sources are included in the definition of indebtedness and are subject to these incurrence tests. | ||||||||||||||||
Genco’s debt incurrence-related ratio restrictions under its indenture may be disregarded if both Moody’s and S&P reaffirm the ratings of Genco in place at the time of the debt incurrence after considering the additional indebtedness. | |||||||||||||||||
As shown in the table above, under the provisions of Genco’s indenture, Genco may not borrow additional funds from external, third-party sources if its interest coverage ratio is less than 2.5 or its debt-to-capital ratio is greater than 60%. Beginning in the first quarter of 2013, Genco’s interest coverage ratio fell to a value less than the specified minimum level required for external borrowings, and Genco expects the ratio to remain less than this minimum level through at least 2015. As a result, Genco’s ability to borrow additional funds from external third-party sources is restricted. Genco’s indenture does not restrict intercompany borrowings from Ameren’s non-state-regulated subsidiary money pool. However, borrowings from the money pool are subject to Ameren’s control. If a Genco intercompany financing need were to arise, borrowings from the non-state-regulated subsidiary money pool by Genco would be dependent on consideration by Ameren of the facts and circumstances existing at that time. As stated above, the transaction agreement requires Ameren to operate New AER, including Genco, in the ordinary course prior to the closing. | |||||||||||||||||
Illinois Sales and Use Tax Exemptions and Credits | |||||||||||||||||
Beginning in the second quarter of 2010 through 2011, Genco, including EEI, and AERG claimed Illinois sales and use tax exemptions and credits for purchase transactions related to their generation operations. During the second quarter of 2013, Ameren and the Illinois Department of Revenue resolved a tax dispute relating to these sales and use tax exemptions and credits for all open periods related to this issue with an aggregate payment of $7 million by Genco, including EEI, and AERG to the Illinois Department of Revenue. This charge was recorded within “Loss from discontinued operations, net of taxes” on Ameren’s consolidated statement of income for the nine months ended September 30, 2013. |
Rate_And_Regulatory_Matters
Rate And Regulatory Matters | 9 Months Ended |
Sep. 30, 2013 | |
Public Utilities, General Disclosures [Abstract] | ' |
RATE AND REGULATORY MATTERS | ' |
RATE AND REGULATORY MATTERS | |
Below is a summary of updates to significant regulatory proceedings and related lawsuits. See also Note 2 - Rate and Regulatory Matters under Part II, Item 8, of the Form 10-K. We are unable to predict the ultimate outcome of these matters, the timing of the final decisions of the various agencies and courts, or the impact on our results of operations, financial position, or liquidity. | |
Missouri | |
FAC Prudence Reviews | |
In April 2011, the MoPSC issued an order with respect to its review of Ameren Missouri's FAC for the period from March 1, 2009, to September 30, 2009. In this order, the MoPSC ruled that Ameren Missouri should have included in the FAC calculation all revenues and costs associated with certain long-term partial requirements sales that were made by Ameren Missouri because of the loss of Noranda's load caused by a severe ice storm in January 2009. In May 2012, upon appeal by Ameren Missouri, the Cole County Circuit Court reversed the MoPSC's April 2011 order. In June 2012, the MoPSC and a group of large industrial customers filed an appeal of the Cole County Circuit Court's ruling to the Missouri Court of Appeals, Western District. In May 2013, the Missouri Court of Appeals upheld the MoPSC’s April 2011 order and reversed the Cole County Circuit Court’s May 2012 decision. Ameren Missouri determined that it would not appeal the Missouri Court of Appeals’ decision. | |
Ameren Missouri’s FAC calculation for the period from October 1, 2009, to May 31, 2011, excluded all revenues and costs associated with certain long-term partial requirements sales that were made by Ameren Missouri because of the loss of Noranda’s load caused by a severe ice storm in January 2009, similar to the FAC calculation for the period from March 1, 2009, to September 30, 2009. As a result of the Missouri Court of Appeal’s May 2013 decision on the MoPSC’s April 2011 order, Ameren Missouri recorded a pretax charge to earnings of $23 million, including $1 million for interest, in the second quarter of 2013 for its estimated obligation to refund to Ameren Missouri’s electric customers the earnings associated with these sales previously recognized by Ameren Missouri for the period from October 1, 2009, to May 31, 2011. Ameren Missouri recorded the charge to “Operating Revenues - Electric” and the related interest to “Interest Charges” with a corresponding offset to “Current regulatory liabilities.” On July 31, 2013, the MoPSC issued an order calculating the refund of these earnings to be $26 million, including $1 million of interest. As a result, during third quarter of 2013, Ameren Missouri recorded an additional pretax charge to earnings of $3 million. Ameren Missouri expects to begin making customer refunds in the first quarter of 2014. No similar revenues were excluded from FAC calculations after May 2011. | |
Separately, in July 2011, Ameren Missouri filed a request with the MoPSC for an accounting authority order that would allow Ameren Missouri to defer, as a regulatory asset, fixed costs totaling $36 million that were not recovered from Noranda as a result of the loss of load caused by the severe 2009 ice storm for potential recovery in a future electric rate case. Ameren Missouri expects the MoPSC to issue an order related to this request in the fourth quarter of 2013. | |
2012 Electric Rate Order | |
In December 2012, the MoPSC issued an order approving an increase for Ameren Missouri in annual revenues for electric service of $260 million. In January 2013, Ameren Missouri appealed the order with respect to the amount of property taxes included in the order to the Missouri Court of Appeals, Western District. In February 2013, the MoOPC, MIEC, and other parties filed separate appeals to the Missouri Court of Appeals, Western District, relating to the 2012 electric rate order’s treatment of transmission costs in the FAC. In July 2013, Ameren Missouri withdrew its appeal related to the 2012 electric rate order. In October 2013, the Missouri Court of Appeals, Western District, issued its opinion affirming the MoPSC’s December 2012 rate order. In October 2013, the MoOPC, MIEC, and other parties filed a rehearing request with the Missouri Court of Appeals, Western District. | |
Illinois | |
IEIMA | |
Under the provisions of the IEIMA, Ameren Illinois’ electric delivery service rates effective in 2013 are subject to an annual revenue requirement reconciliation to its actual 2013 costs. The 2013 revenue requirement reconciliation will be filed with the ICC in 2014. The approved annual revenue requirement reconciliation adjustment will be reflected in customer rates beginning in January 2015. Throughout the year, Ameren Illinois records a regulatory asset or a regulatory liability and a corresponding increase or decrease to operating revenues for any differences between the revenue requirement in effect for that year and its estimate of the probable increase or decrease in the revenue requirement expected to ultimately be approved by the ICC based on that year's actual costs incurred. As of September 30, 2013, Ameren Illinois recorded a $59 million regulatory asset to reflect the year-to-date portion of its expected 2013 revenue requirement reconciliation adjustment. As of September 30, 2013 and December 31, 2012, Ameren Illinois recorded a regulatory liability of $59 million and $55 million, respectively, to reflect its expected 2012 revenue requirement reconciliation adjustment, with interest, which will be refunded to customers in 2014, pending ICC approval as discussed below. | |
In May 2013, Illinois enacted into law certain amendments to the IEIMA that modify its implementation. The law clarified that the IEIMA requires that the year-end rate base be used to calculate the revenue requirement reconciliation and that the interest applied to the revenue requirement reconciliation and return on equity collar adjustments be equal to a company’s weighted-average return calculated under the formula rate. | |
In September 2012, the ICC issued an order in Ameren Illinois’ initial filing under the IEIMA’s performance-based formula rate framework, which Ameren Illinois appealed to the Appellate Court of the Fourth District of Illinois. A decision by the appellate court is expected in 2014. In December 2012, the ICC issued an order in Ameren Illinois’ update filing approving an Ameren Illinois electric delivery service revenue requirement of $765 million, based on 2011 recoverable costs and expected net plant additions for 2012. The delivery service rates became effective on January 1, 2013, and will remain effective through the end of 2013. These rates are subject to a reconciliation to actual 2013 costs, which will be filed with the ICC in 2014. In January 2013, Ameren Illinois filed an appeal of the ICC's update filing order to the Appellate Court of the Fourth District of Illinois. A decision by the appellate court is expected in 2014. Many of the issues that were the subject of Ameren Illinois’ appeals of the September 2012 order and the December 2012 order were resolved with the enactment of the May 2013 amendments to the IEIMA referred to above; however, disputes regarding the treatment of deferred taxes and vacation obligations as well as the calculation of Ameren Illinois’ capital structure remain. If the appellate court rules in favor of Ameren Illinois’ positions on these disputed items, the electric delivery service revenue requirement included in the December 2012 order would have increased by $11 million. Ameren Illinois anticipates that any change resulting from the appellate court decision would be incorporated into the IEIMA formula rate process, including the revenue requirement reconciliation, in the year the decision is issued. | |
In April 2013, Ameren Illinois filed its annual electric delivery service formula rate update with the ICC based on 2012 recoverable costs and expected net plant additions for 2013. In July 2013, the update filing was revised based on the enactment of the May 2013 amendments to the IEIMA referred to above. Pending ICC approval, Ameren Illinois’ revised update filing would result in an aggregate $22 million decrease in Ameren Illinois’ electric delivery service revenue requirement beginning in January 2014. The revised update filing includes a proposed refund to customers of the 2012 revenue requirement reconciliation of $55 million, which includes an estimate for interest through the end of 2014. Ameren Illinois’ balance sheet as of September 30, 2013, includes a $59 million regulatory liability relating to this 2012 revenue requirement reconciliation, which will continue to accrue interest through 2014 and is expected to increase to $63 million with interest accrued through 2014. In the revised update filing, the proposed refund is partially offset by an annual revenue requirement increase of $33 million primarily due to increased recoverable costs over 2011 levels. Ameren Illinois’ filing reflects an electric delivery service revenue requirement of $798 million, before consideration of the 2012 revenue requirement reconciliation refund. In October 2013, the ICC staff submitted its calculation of the revenue requirement included in Ameren Illinois’ revised update filing. The ICC staff recommended an aggregate $42 million decrease in Ameren Illinois’ electric delivery service revenue requirement. The calculation includes a refund to customers of the 2012 revenue requirement reconciliation of $66 million, which includes an estimate for interest through the end of 2014. However, this refund is partially offset by an annual revenue requirement increase of $24 million primarily due to increased recoverable costs over 2011 levels. The ICC staff’s filing reflects an electric delivery service revenue requirement of $789 million, before consideration of the 2012 revenue requirement reconciliation refund. An ICC decision with respect to the update filing is required in December 2013 and will establish rates for all of 2014. In December 2013, Ameren Illinois will record an adjustment to its regulatory liability for its 2012 revenue requirement reconciliation refund based on the ICC’s order. | |
2013 Natural Gas Delivery Service Rate Case | |
In January 2013, Ameren Illinois filed a request with the ICC to increase its annual revenues for natural gas delivery service. The current request, as revised in August 2013, seeks to increase annual revenues for natural gas delivery service by $47 million. The revised natural gas rate increase request was based on a 10.4% return on equity, a capital structure composed of 51.8% common equity, and a rate base of $1.1 billion. In an attempt to reduce regulatory lag, Ameren Illinois is using a future test year of 2014 in this proceeding. | |
Also in its filing, Ameren Illinois is seeking recovery of capital costs to enable residential customers the option to choose their natural gas commodity supplier, although that option currently does not exist for these customers. | |
In September 2013, the ICC staff responded to Ameren Illinois' revised request and recommended an increase in revenues for natural gas delivery service of $28 million, based on an 8.8% return on equity, a capital structure composed of 50.4% common equity, and a rate base of $1.1 billion. | |
A decision by the ICC in this proceeding is required in December 2013. Ameren Illinois cannot predict the level of any natural gas delivery service rate changes the ICC may approve or whether any rate changes that may eventually be approved will be sufficient to enable Ameren Illinois to recover its costs and earn a reasonable return on its investments when the rate changes go into effect. | |
Natural Gas Consumer, Safety and Reliability Act | |
In July 2013, Illinois enacted a law called the Natural Gas Consumer, Safety and Reliability Act that enables Illinois natural gas utilities to accelerate modernization of the state’s natural gas infrastructure and provide additional ICC oversight of natural gas utility performance. Utilities that participate may implement rate surcharges for certain infrastructure investments made between rate cases. The legislation allows natural gas utilities the option to file, and requires the ICC to approve, a rate rider mechanism to provide for recovery of costs associated with certain categories of investment to improve the safety and reliability of the state’s natural gas infrastructure. The legislation also requires natural gas utilities that choose to participate in this regulatory framework to file annual plans with the ICC and report on progress in achieving performance improvements. Ameren Illinois expects to begin participation in this regulatory framework in 2014. | |
ATXI Transmission Project | |
ATXI’s Illinois Rivers project is a MISO-approved project to build a 345-kilovolt line from western Indiana across the state of Illinois to eastern Missouri at an estimated cost of $1.1 billion. In 2012, ATXI made a filing with the ICC requesting a certificate of public convenience and necessity, and project approval. In August 2013, the ICC granted a certificate of public convenience and necessity and approved seven of a total of nine sections of the route and three of the proposed nine substations for the Illinois Rivers project. The ICC order indicated the project is necessary to address transmission and reliability needs in an efficient and equitable manner and that the project will benefit the development of a competitive electricity market. The order also indicated that ATXI is capable of constructing and managing the project and capable of financing it. In October 2013, the ICC granted ATXI’s request for rehearing to consider additional evidence regarding the two segments of the route and six substations that were not approved, as well as the requests for rehearing of certain other parties regarding two of the approved segments of the route. An order on rehearing is expected in March 2014. | |
Federal | |
2011 Wholesale Distribution Rate Case | |
In January 2011, Ameren Illinois filed a request with FERC to increase its annual revenues for electric delivery service for its wholesale customers. These wholesale distribution revenues are treated as a deduction from Ameren Illinois’ revenue requirement in retail rate filings with the ICC. In March 2011, FERC issued an order authorizing the proposed rates to take effect, subject to refund when the final rates are determined. Ameren Illinois has reached an agreement with four of its nine wholesale customers. The impasse with the remaining five wholesale customers has resulted in FERC litigation. In November 2012, a FERC administrative law judge issued an initial decision, which is now pending before FERC. The timing of a FERC decision is uncertain. Based on the administrative law judge's initial decision, Ameren and Ameren Illinois each has included on its balance sheet in “Current regulatory liabilities” an estimate of $12 million and $8 million as of September 30, 2013, and December 31, 2012, respectively, for the refund due to wholesale customers relating to billings for the period from March 2011 through September 2013. | |
Ameren Illinois Electric Transmission Rate Refund | |
In July 2012, FERC issued an order with respect to Ameren Illinois' accounting for the Ameren Illinois Merger. As part of this order, FERC concluded that Ameren Illinois improperly included acquisition premiums, particularly goodwill, in determining its common equity used in its electric transmission formula rate, thereby inappropriately recovering a higher return on rate base from its electric transmission customers. The order required Ameren Illinois to make refunds to customers for such improperly included amounts. In August 2012, Ameren Illinois filed a request for rehearing of this order. It is unknown when FERC will rule on Ameren's rehearing request, as it is under no deadline to do so. Ameren Illinois submitted a refund report in November 2012 and concluded that no refund was warranted. Several wholesale customers filed a protest with FERC regarding Ameren's conclusion that no refund is warranted. | |
In June 2013, FERC issued an order that rejected Ameren Illinois’ November 2012 refund report and provided guidance as to the filing of a new refund report. In July 2013, Ameren Illinois filed a revised refund report based on the guidance provided in the June 2013 order, and also filed a request for rehearing of that order. Ameren Illinois’ July 2013 refund report again concluded that no refund was warranted. Ameren Illinois estimates the maximum pretax charge to earnings for this contingency would be between $10 million and $15 million, before interest charges. If Ameren Illinois were to determine that a refund to its electric transmission customers is probable, a charge to earnings would be recorded for the refund in the period in which that determination was made. | |
Combined Construction and Operating License | |
In 2008, Ameren Missouri filed an application with the NRC for a COL for a new nuclear unit at Ameren Missouri's existing Callaway County, Missouri, energy center site. In 2009, Ameren Missouri suspended its efforts to build a new nuclear unit at its existing Missouri nuclear energy center site, and the NRC suspended review of the COL application. | |
In March 2012, the DOE announced the availability of investment funds for the design, engineering, manufacturing, and sale of American-made small modular nuclear reactors. In April 2012, Ameren Missouri entered into an agreement with Westinghouse to exclusively support Westinghouse's application for the first installment of DOE's small modular nuclear reactor investment funds. The DOE investment funding is intended to support engineering and design certifications and a COL for up to two small modular reactor designs over five years. In November 2012, the DOE awarded the first installment of investment funds for only one small modular reactor design, which was not the Westinghouse design, but also stated that a second installment of investment funds would be awarded during 2013. Westinghouse continues to seek funds from the DOE’s first installment of investment funds. | |
Westinghouse submitted an application to the DOE in June 2013 for the second installment of investment funds. If Westinghouse is awarded DOE's small modular reactor investment funds in this second installment round of funding, Ameren Missouri may pursue a COL from the NRC for a Westinghouse small modular reactor or multiple reactors at its Callaway energy center site. A COL is issued by the NRC to permit construction and operation of a nuclear energy center at a specific site in accordance with established laws and regulations. Obtaining a COL from the NRC would not obligate Ameren Missouri to build a small modular reactor at the Callaway site; however, it would preserve the option to move forward in a timely fashion should conditions be right to build a small modular reactor in the future. A COL is valid for at least 40 years. | |
Ameren Missouri estimates the total cost to obtain the small modular reactor COL will be in the range of $80 million to $100 million. As of September 30, 2013, Ameren Missouri has capitalized investments for the development of a new nuclear energy center of $69 million. Ameren Missouri expects its incremental investment to obtain the small modular reactor COL to be minimal. As discussed above, the DOE investment funds could help support the completion of a COL application. If the DOE does not select Westinghouse's applications for small modular reactor investment funds, Ameren Missouri is not obligated to pursue a COL for the Westinghouse small modular reactor design and may terminate its agreement with Westinghouse regarding the first installment of DOE investment funds. | |
All of Ameren Missouri's costs incurred to license additional nuclear generation at the Callaway site will remain capitalized while management pursues options to maximize the value of its investment. If efforts are permanently abandoned or management concludes it is probable the costs incurred will be disallowed in rates, a charge to earnings would be recognized in the period in which that determination is made. |
ShortTerm_Debt_And_Liquidity
Short-Term Debt And Liquidity | 9 Months Ended |
Sep. 30, 2013 | |
Line of Credit Facility [Abstract] | ' |
SHORT-TERM DEBT AND LIQUIDITY | ' |
SHORT-TERM DEBT AND LIQUIDITY | |
The liquidity needs of the Ameren Companies are typically supported through the use of available cash, short-term intercompany borrowings, drawings under committed bank credit agreements, or commercial paper issuances. | |
The 2012 Missouri Credit Agreement and the 2012 Illinois Credit Agreement were not utilized for borrowings during the nine months ended September 30, 2013. As of September 30, 2013, based on letters of credit issued under the 2012 Credit Agreements, as well as commercial paper outstanding, the aggregate amount of credit capacity available to Ameren (parent), Ameren Missouri and Ameren Illinois, collectively, at September 30, 2013, was $2.09 billion. | |
Commercial Paper | |
Ameren did not have any commercial paper outstanding at September 30, 2013, or December 31, 2012. The average daily commercial paper balances outstanding during the nine months ended September 30, 2013, and 2012, were $26 million and $58 million, respectively. The weighted-average interest rates during the nine months ended September 30, 2013, and 2012, were 0.52% and 0.93%, respectively. The peak short-term commercial paper balances outstanding during the nine months ended September 30, 2013, and 2012, were $92 million and $229 million, respectively. The peak interest rates during the nine months ended September 30, 2013, and 2012, were 0.85% and 1.25%, respectively. Ameren Missouri and Ameren Illinois did not utilize their commercial paper programs during the nine months ended September 30, 2013, and 2012. | |
Indebtedness Provisions and Other Covenants | |
The information below presents a summary of the Ameren Companies’ compliance with indebtedness provisions and other covenants within the 2012 Credit Agreements. See Note 4 – Short-term Debt and Liquidity under Part II, Item 8, in the Form 10-K for a detailed description of these provisions. | |
The 2012 Credit Agreements contain nonfinancial covenants, including restrictions on the ability to incur liens, to transact with affiliates, to dispose of assets, to make investments in or transfer assets to its affiliates, and to merge with other entities. The 2012 Credit Agreements require each of Ameren, Ameren Missouri and Ameren Illinois to maintain consolidated indebtedness of not more than 65% of its consolidated total capitalization pursuant to a defined calculation set forth in the agreements. As of September 30, 2013, the ratios of consolidated indebtedness to total consolidated capitalization, calculated in accordance with the provisions of the 2012 Credit Agreements, were 51%, 48% and 42%, for Ameren, Ameren Missouri and Ameren Illinois, respectively. In addition, under the 2012 Illinois Credit Agreement and by virtue of the cross-default provisions of the 2012 Missouri Credit Agreement, Ameren is required to maintain a ratio of consolidated funds from operations plus interest expense to consolidated interest expense of 2.0 to 1, to be calculated quarterly, as of the end of the most recent four fiscal quarters then ending, in accordance with the 2012 Illinois Credit Agreement. Ameren’s ratio as of September 30, 2013, was 5.1 to 1.0. Failure of a borrower to satisfy a financial covenant constitutes an immediate default under the applicable 2012 Credit Agreement. Ameren’s ratios, as discussed above, include both continuing and discontinued operations for the purposes of these calculations. | |
None of the Ameren Companies' credit agreements or financing arrangements contain credit rating triggers that would cause a default or acceleration of repayment of outstanding balances. Management believes that the Ameren Companies were in compliance with the provisions and covenants of their credit agreements at September 30, 2013. | |
Money Pools | |
Ameren has money pool agreements with and among its subsidiaries to coordinate and provide for certain short-term cash and working capital requirements. Separate money pools are maintained for utility and non-state-regulated entities. Ameren Services is responsible for the operation and administration of the money pool agreements. | |
Utility | |
Ameren Missouri, Ameren Illinois and Ameren Services may participate in the utility money pool as both lenders and borrowers. Ameren (parent) and AERG may participate in the utility money pool only as lenders. Internal funds are surplus funds contributed to the utility money pool from participants. The primary sources of external funds for the utility money pool are the 2012 Credit Agreements and the commercial paper programs. The total amount available to the pool participants from the utility money pool at any given time is reduced by the amount of borrowings made by participants, but is increased to the extent that the pool participants advance surplus funds to the utility money pool or remit funds from other external sources. The availability of funds is also determined by funding requirement limits established by regulatory authorizations. The utility money pool was established to coordinate and to provide short-term cash and working capital for the participants. Participants receiving a loan under the utility money pool agreement must repay the principal amount of such loan, together with accrued interest. The rate of interest depends on the composition of internal and external funds in the utility money pool. The average interest rates for borrowing under the utility money pool for the three and nine months ended September 30, 2013, were 0.05% and 0.08%, respectively (2012 - 0.14% and 0.13%, respectively). | |
Non-state-regulated Subsidiaries | |
Ameren (parent), Ameren Services, AER, Genco, AERG, Marketing Company, and other non-state-regulated Ameren subsidiaries have the ability, subject to Ameren parent company and applicable regulatory short-term borrowing authorizations, to access funding from the 2012 Credit Agreements and the commercial paper programs through a non-state-regulated subsidiary money pool agreement. AER, Genco, AERG and Marketing Company may participate in the non-state-regulated money pool through the closing of the divestiture transaction as detailed in Note 2 - Divestiture Transactions and Discontinued Operations. All participants may borrow from or lend to the non-state-regulated money pool, except for Ameren Services, which may participate only as a borrower. The total amount available to the pool participants from the non-state-regulated subsidiary money pool at any given time is reduced by the amount of borrowings made by participants, but is increased to the extent that the pool participants advance surplus funds to the non-state-regulated subsidiary money pool or remit funds from other external sources. The non-state-regulated subsidiary money pool was established to coordinate and to provide short-term cash and working capital for the participants. Participants receiving a loan under the non-state-regulated subsidiary money pool agreement must repay the principal amount of such loan, together with accrued interest. The rate of interest depends on the composition of internal and external funds in the non-state-regulated subsidiary money pool. The average interest rates for borrowing under the non-state-regulated subsidiary money pool for the three and nine months ended September 30, 2013, were 0.36% and 0.29%, respectively (2012 - 0.52% and 0.64%, respectively). | |
See Note 9 - Related Party Transactions for the amount of interest income and expense from the money pool arrangements recorded by the Ameren Companies for the three and nine months ended September 30, 2013, and 2012. |
LongTerm_Debt_And_Equity_Finan
Long-Term Debt And Equity Financings | 9 Months Ended | ||||||||||||||
Sep. 30, 2013 | |||||||||||||||
Long-Term Debt And Equity Financings [Abstract] | ' | ||||||||||||||
LONG-TERM DEBT AND EQUITY FINANCINGS | ' | ||||||||||||||
LONG-TERM DEBT AND EQUITY FINANCINGS | |||||||||||||||
Ameren Missouri | |||||||||||||||
In October 2013, $44 million of Ameren Missouri’s 1993 5.45% Series tax-exempt first mortgage bonds were redeemed at par plus accrued interest. In October 2013, $200 million of Ameren Missouri’s 4.65% senior secured notes matured and were retired. | |||||||||||||||
Indenture Provisions and Other Covenants | |||||||||||||||
Ameren Missouri’s and Ameren Illinois’ indentures and articles of incorporation include covenants and provisions related to issuances of first mortgage bonds and preferred stock. Ameren Missouri and Ameren Illinois are required to meet certain ratios to issue additional first mortgage bonds and preferred stock. A failure to achieve these ratios would not result in a default under these covenants and provisions, but would restrict the companies’ ability to issue bonds or preferred stock. The following table summarizes the required and actual interest coverage ratios for interest charges and dividend coverage ratios and bonds and preferred stock issuable as of September 30, 2013, at an assumed annual interest rate of 6% and dividend rate of 7%. | |||||||||||||||
Required Interest | Actual Interest | Bonds Issuable(b) | Required Dividend | Actual Dividend | Preferred Stock | ||||||||||
Coverage Ratio(a) | Coverage Ratio | Coverage Ratio(c) | Coverage Ratio | Issuable | |||||||||||
Ameren Missouri | ≥2.0 | 4.3 | $ | 3,564 | ≥2.5 | 111.5 | $ | 2,130 | |||||||
Ameren Illinois | ≥2.0 | 7.4 | 3,536 | (d) | ≥1.5 | 2.7 | 203 | ||||||||
(a) | Coverage required on the annual interest charges on first mortgage bonds outstanding and to be issued. Coverage is not required in certain cases when additional first mortgage bonds are issued on the basis of retired bonds. | ||||||||||||||
(b) | Amount of bonds issuable based either on required coverage ratios or unfunded property additions, whichever is more restrictive. The amounts shown also include bonds issuable based on retired bond capacity of $485 million and $645 million at Ameren Missouri and Ameren Illinois, respectively. | ||||||||||||||
(c) | Coverage required on the annual dividend on preferred stock outstanding and to be issued, as required in the respective company’s articles of incorporation. | ||||||||||||||
(d) | Amount of bonds issuable by Ameren Illinois based on unfunded property additions and retired bonds solely under the former IP mortgage indenture. | ||||||||||||||
Ameren’s indenture does not require Ameren to comply with any quantitative financial covenants. The indenture does, however, include certain cross-default provisions. Specifically, either (1) the failure by Ameren to pay when due and upon expiration of any applicable grace period any portion of any Ameren indebtedness in excess of $25 million or (2) the acceleration upon default of the maturity of any Ameren indebtedness in excess of $25 million under any indebtedness agreement, including the 2012 Credit Agreements, constitutes a default under the indenture, unless such past due or accelerated debt is discharged or the acceleration is rescinded or annulled within a specified period. | |||||||||||||||
Ameren Missouri and Ameren Illinois and certain other Ameren subsidiaries are subject to Section 305(a) of the Federal Power Act, which makes it unlawful for any officer or director of a public utility, as defined in the Federal Power Act, to participate in the making or paying of any dividend from any funds “properly included in capital account.” FERC has consistently interpreted the provision to allow dividends to be paid as long as (1) the source of the dividends is clearly disclosed, (2) the dividends are not excessive, and (3) there is no self-dealing on the part of corporate officials. At a minimum, Ameren believes that dividends can be paid by its subsidiaries that are public utilities from net income and retained earnings. In addition, under Illinois law, Ameren Illinois may not pay any dividend on its stock, unless, among other things, its earnings and earned surplus are sufficient to declare and pay a dividend after provision is made for reasonable and proper reserves, or unless Ameren Illinois has specific authorization from the ICC. | |||||||||||||||
Ameren Illinois’ articles of incorporation require dividend payments on its common stock to be based on ratios of common stock to total capitalization and other provisions related to certain operating expenses and accumulations of earned surplus. Ameren Illinois committed to FERC to maintain a minimum 30% ratio of common stock equity to total capitalization after the Ameren Illinois Merger and AERG distribution. As of September 30, 2013, Ameren Illinois’ ratio of common stock equity to total capitalization was 58%. | |||||||||||||||
In order for the Ameren Companies to issue securities in the future, they will have to comply with all applicable requirements in effect at the time of any such issuances. | |||||||||||||||
Off-Balance-Sheet Arrangements | |||||||||||||||
At September 30, 2013, none of the Ameren Companies had any off-balance-sheet financing arrangements, other than operating leases entered into in the ordinary course of business. None of the Ameren Companies expect to engage in any significant off-balance-sheet financing arrangements in the near future. |
Other_Income_and_Expenses
Other Income and Expenses | 9 Months Ended | ||||||||||||||||
Sep. 30, 2013 | |||||||||||||||||
Other Nonoperating Income (Expense) [Abstract] | ' | ||||||||||||||||
OTHER INCOME AND EXPENSES | ' | ||||||||||||||||
OTHER INCOME AND EXPENSES | |||||||||||||||||
The following table presents the components of “Other Income and Expenses” in the Ameren Companies’ statements of income for the three and nine months ended September 30, 2013, and 2012: | |||||||||||||||||
Three Months | Nine Months | ||||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||||
Ameren:(a) | |||||||||||||||||
Miscellaneous income: | |||||||||||||||||
Allowance for equity funds used during construction | $ | 10 | $ | 9 | $ | 26 | $ | 26 | |||||||||
Interest income on industrial development revenue bonds | 7 | 7 | 21 | 21 | |||||||||||||
Interest and dividend income | 2 | — | 3 | 4 | (b) | ||||||||||||
Other | 1 | 1 | 1 | 2 | |||||||||||||
Total miscellaneous income | $ | 20 | $ | 17 | $ | 51 | $ | 53 | |||||||||
Miscellaneous expense: | |||||||||||||||||
Donations | $ | 2 | $ | 3 | $ | 7 | $ | 18 | (c) | ||||||||
Other | 3 | 3 | 11 | 10 | |||||||||||||
Total miscellaneous expense | $ | 5 | $ | 6 | $ | 18 | $ | 28 | |||||||||
Ameren Missouri: | |||||||||||||||||
Miscellaneous income: | |||||||||||||||||
Allowance for equity funds used during construction | $ | 8 | $ | 8 | $ | 22 | $ | 23 | |||||||||
Interest income on industrial development revenue bonds | 7 | 7 | 21 | 21 | |||||||||||||
Interest and dividend income | 1 | — | 1 | 4 | (b) | ||||||||||||
Total miscellaneous income | $ | 16 | $ | 15 | $ | 44 | $ | 48 | |||||||||
Miscellaneous expense: | |||||||||||||||||
Donations | $ | — | $ | 2 | $ | 3 | $ | 7 | |||||||||
Other | 2 | 2 | 7 | 4 | |||||||||||||
Total miscellaneous expense | $ | 2 | $ | 4 | $ | 10 | $ | 11 | |||||||||
Ameren Illinois: | |||||||||||||||||
Miscellaneous income: | |||||||||||||||||
Allowance for equity funds used during construction | $ | 2 | $ | 1 | $ | 4 | $ | 3 | |||||||||
Interest and dividend income | 1 | — | 2 | — | |||||||||||||
Other | 1 | 1 | 1 | 2 | |||||||||||||
Total miscellaneous income | $ | 4 | $ | 2 | $ | 7 | $ | 5 | |||||||||
Miscellaneous expense: | |||||||||||||||||
Donations | $ | — | $ | 1 | $ | 3 | $ | 11 | (c) | ||||||||
Other | 3 | 1 | 4 | 4 | |||||||||||||
Total miscellaneous expense | $ | 3 | $ | 2 | $ | 7 | $ | 15 | |||||||||
(a) | Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations. | ||||||||||||||||
(b) | Includes interest income received in 2012 relating to a refund of charges included in an expired power purchase agreement with Entergy. | ||||||||||||||||
(c) | Includes Ameren Illinois’ one-time $7.5 million contribution to the Illinois Science and Energy Innovation Trust pursuant to the IEIMA as a result of Ameren Illinois’ 2012 election to participate in the formula ratemaking process. |
Derivative_Financial_Instrumen
Derivative Financial Instruments | 9 Months Ended | |||||||||||||||||||
Sep. 30, 2013 | ||||||||||||||||||||
Derivative Instruments and Hedging Activities Disclosure [Abstract] | ' | |||||||||||||||||||
DERIVATIVE FINANCIAL INSTRUMENTS | ' | |||||||||||||||||||
DERIVATIVE FINANCIAL INSTRUMENTS | ||||||||||||||||||||
We use derivatives principally to manage the risk of changes in market prices for natural gas, coal, diesel, power, and uranium. Such price fluctuations may cause the following: | ||||||||||||||||||||
• | an unrealized appreciation or depreciation of our contracted commitments to purchase or sell when purchase or sale prices under the commitments are compared with current commodity prices; | |||||||||||||||||||
• | market values of coal, natural gas, and uranium inventories that differ from the cost of those commodities in inventory; and | |||||||||||||||||||
• | actual cash outlays for the purchase of these commodities that differ from anticipated cash outlays. | |||||||||||||||||||
The derivatives that we use to hedge these risks are governed by our risk management policies for forward contracts, futures, options, and swaps. Our net positions are continually assessed within our structured hedging programs to determine whether new or offsetting transactions are required. The goal of the hedging program is generally to mitigate financial risks while ensuring that sufficient volumes are available to meet our requirements. Contracts we enter into as part of our risk management program may be settled financially, settled by physical delivery, or net settled with the counterparty. | ||||||||||||||||||||
The following table presents open gross commodity contract volumes by commodity type as of September 30, 2013, and December 31, 2012: | ||||||||||||||||||||
Quantity (in millions, except as indicated) | ||||||||||||||||||||
Commodity | Accrual & NPNS | Other | Derivatives That Qualify | |||||||||||||||||
Contracts(a) | Derivatives(b) | for Regulatory Deferral(c) | ||||||||||||||||||
2013 | 2012 | 2013 | 2012 | 2013 | 2012 | |||||||||||||||
Coal (in tons) | ||||||||||||||||||||
Ameren Missouri & Ameren | 81 | 96 | (d) | (d) | (d) | (d) | ||||||||||||||
Fuel oils (in gallons)(e) | ||||||||||||||||||||
Ameren Missouri & Ameren | (d) | (d) | (d) | (d) | 60 | 70 | ||||||||||||||
Natural gas (in mmbtu) | ||||||||||||||||||||
Ameren Missouri | 2 | 4 | — | — | 29 | 19 | ||||||||||||||
Ameren Illinois | 6 | 16 | (d) | (d) | 115 | 128 | ||||||||||||||
Ameren | 8 | 20 | — | — | 144 | 147 | ||||||||||||||
Power (in megawatthours) | ||||||||||||||||||||
Ameren Missouri | 3 | 3 | 1 | 2 | 5 | 9 | ||||||||||||||
Ameren Illinois | 15 | 21 | (d) | (d) | 11 | 14 | ||||||||||||||
Ameren | 18 | 24 | 1 | 2 | 16 | 23 | ||||||||||||||
Renewable energy credits(f) | ||||||||||||||||||||
Ameren Missouri | 3 | 3 | (d) | (d) | (d) | (d) | ||||||||||||||
Ameren Illinois | 11 | 12 | (d) | (d) | (d) | (d) | ||||||||||||||
Ameren | 14 | 15 | (d) | (d) | (d) | (d) | ||||||||||||||
Uranium (pounds in thousands) | ||||||||||||||||||||
Ameren Missouri & Ameren | 4,516 | 5,142 | (d) | (d) | 996 | 446 | ||||||||||||||
(a) | Accrual contracts include commodity contracts that do not qualify as derivatives. As of September 30, 2013, these contracts ran through December 2017, March 2015, September 2024, May 2032, and October 2024 for coal, natural gas, power, renewable energy credits, and uranium, respectively. | |||||||||||||||||||
(b) | As of September 30, 2013, these contracts ran through December 2014 for power. | |||||||||||||||||||
(c) | As of September 30, 2013, these contracts ran through October 2015, October 2019, May 2032, and October 2016 for fuel oils, natural gas, power, and uranium, respectively. | |||||||||||||||||||
(d) | Not applicable. | |||||||||||||||||||
(e) | Fuel oils consist of heating oil, ultra-low sulfur diesel, and crude oil. | |||||||||||||||||||
(f) | A renewable energy credit is created for every one megawatthour of renewable energy generated. The Ameren Companies’ contracts include renewable energy credits from solar and wind-generated power. | |||||||||||||||||||
Authoritative accounting guidance regarding derivative instruments requires that all contracts considered to be derivative instruments be recorded on the balance sheet at their fair values, unless the NPNS exception applies. See Note 8 - Fair Value Measurements for our methods of assessing the fair value of derivative instruments. Many of our physical contracts, such as our purchased power contracts, qualify for the NPNS exception to derivative accounting rules. The revenue or expense on NPNS contracts is recognized at the contract price upon physical delivery. | ||||||||||||||||||||
If we determine that a contract meets the definition of a derivative and is not eligible for the NPNS exception, we review the contract to determine if it qualifies for hedge accounting. We also consider whether gains or losses resulting from such derivatives qualify for regulatory deferral. Contracts that qualify for cash flow hedge accounting are recorded at fair value with changes in fair value charged or credited to accumulated OCI in the period in which the change occurs, to the extent the hedge is effective. To the extent the hedge is ineffective, the related changes in fair value are charged or credited to the statement of income or the statement of income and comprehensive income in the period in which the change occurs. When the contract is settled or delivered, the net gain or loss is recorded in the statement of income or the statement of income and comprehensive income. Currently, we have not elected cash flow hedge accounting for any of our derivative contracts. | ||||||||||||||||||||
Derivative contracts that qualify for regulatory deferral are recorded at fair value, with changes in fair value recorded as regulatory assets or regulatory liabilities in the period in which the change occurs. Ameren Missouri and Ameren Illinois believe derivative gains and losses deferred as regulatory assets and regulatory liabilities are probable of recovery or refund through future rates charged to customers. Regulatory assets and regulatory liabilities are amortized to operating income as related losses and gains are reflected in rates charged to customers. Therefore, gains and losses on these derivatives have no effect on operating income. | ||||||||||||||||||||
Certain derivative contracts are entered into on a regular basis as part of our risk management program but do not qualify for, or we do not choose to elect, the NPNS exception, hedge accounting, or regulatory deferral accounting. Such contracts are recorded at fair value, with changes in fair value charged or credited to the statement of income or the statement of income and comprehensive income in the period in which the change occurs. | ||||||||||||||||||||
Authoritative accounting guidance permits companies to offset fair value amounts recognized for the right to reclaim cash collateral (a receivable) or the obligation to return cash collateral (a liability) against fair value amounts recognized for derivative instruments that are executed with the same counterparty under the same master netting arrangement. The Ameren Companies did not elect to adopt this guidance for any eligible commodity contracts. | ||||||||||||||||||||
The following table presents the carrying value and balance sheet location of all derivative instruments as of September 30, 2013, and December 31, 2012: | ||||||||||||||||||||
Balance Sheet Location | Ameren | Ameren Missouri | Ameren Illinois | |||||||||||||||||
2013 | ||||||||||||||||||||
Derivative assets not designated as hedging instruments(a) | ||||||||||||||||||||
Commodity contracts: | ||||||||||||||||||||
Fuel oils | Other current assets | $ | 6 | $ | 6 | $ | — | |||||||||||||
Other assets | 2 | 2 | — | |||||||||||||||||
Natural gas | Other current assets | 1 | 1 | — | ||||||||||||||||
Power | Other current assets | 30 | 30 | — | ||||||||||||||||
Other assets | 1 | 1 | — | |||||||||||||||||
Uranium | Other current assets | 1 | 1 | — | ||||||||||||||||
Total assets | $ | 41 | $ | 41 | $ | — | ||||||||||||||
Derivative liabilities not designated as hedging instruments(a) | ||||||||||||||||||||
Commodity contracts: | ||||||||||||||||||||
Fuel oils | MTM derivative liabilities | $ | 3 | $ | (b) | $ | — | |||||||||||||
Other current liabilities | — | 3 | — | |||||||||||||||||
Other deferred credits and liabilities | 1 | 1 | — | |||||||||||||||||
Natural gas | MTM derivative liabilities | 45 | (b) | 38 | ||||||||||||||||
Other current liabilities | — | 7 | — | |||||||||||||||||
Other deferred credits and liabilities | 30 | 6 | 24 | |||||||||||||||||
Power | MTM derivative liabilities | 13 | (b) | 10 | ||||||||||||||||
Other current liabilities | — | 3 | — | |||||||||||||||||
Other deferred credits and liabilities | 84 | — | 84 | |||||||||||||||||
Uranium | MTM derivative liabilities | 4 | (b) | — | ||||||||||||||||
Other current liabilities | — | 4 | — | |||||||||||||||||
Other deferred credits and liabilities | 2 | 2 | — | |||||||||||||||||
Total liabilities | $ | 182 | $ | 26 | $ | 156 | ||||||||||||||
2012 | ||||||||||||||||||||
Derivative assets not designated as hedging instruments(a) | ||||||||||||||||||||
Commodity contracts: | ||||||||||||||||||||
Fuel oils | Other current assets | $ | 8 | $ | 8 | $ | — | |||||||||||||
Other assets | 4 | 4 | — | |||||||||||||||||
Natural gas | Other current assets | 1 | — | 1 | ||||||||||||||||
Other assets | 1 | 1 | — | |||||||||||||||||
Power | Other current assets | 14 | 14 | — | ||||||||||||||||
Other assets | 1 | 1 | — | |||||||||||||||||
Total assets | $ | 29 | $ | 28 | $ | 1 | ||||||||||||||
Derivative liabilities not designated as hedging instruments(a) | ||||||||||||||||||||
Commodity contracts: | ||||||||||||||||||||
Fuel oils | MTM derivative liabilities | $ | 2 | $ | (b) | $ | — | |||||||||||||
Other current liabilities | — | 2 | — | |||||||||||||||||
Other deferred credits and liabilities | 2 | 2 | — | |||||||||||||||||
Natural gas | MTM derivative liabilities | 64 | (b) | 56 | ||||||||||||||||
Other current liabilities | — | 8 | — | |||||||||||||||||
Other deferred credits and liabilities | 45 | 7 | 38 | |||||||||||||||||
Power | MTM derivative liabilities | 25 | (b) | 21 | ||||||||||||||||
Other current liabilities | — | 4 | — | |||||||||||||||||
Other deferred credits and liabilities | 90 | — | 90 | |||||||||||||||||
Uranium | MTM derivative liabilities | 1 | (b) | — | ||||||||||||||||
Other current liabilities | — | 1 | — | |||||||||||||||||
Other deferred credits and liabilities | 1 | 1 | — | |||||||||||||||||
Total liabilities | $ | 230 | $ | 25 | $ | 205 | ||||||||||||||
(a) | Includes derivatives subject to regulatory deferral. | |||||||||||||||||||
(b) | Balance sheet line item not applicable to registrant. | |||||||||||||||||||
The following table presents the cumulative amount of pretax net gains (losses) on all derivative instruments deferred in regulatory assets or regulatory liabilities as of September 30, 2013, and December 31, 2012: | ||||||||||||||||||||
Ameren | Ameren | Ameren | ||||||||||||||||||
Missouri | Illinois | |||||||||||||||||||
2013 | ||||||||||||||||||||
Cumulative gains (losses) deferred in regulatory liabilities or assets: | ||||||||||||||||||||
Fuel oils derivative contracts(a) | $ | 1 | $ | 1 | $ | — | ||||||||||||||
Natural gas derivative contracts(b) | (74 | ) | (12 | ) | (62 | ) | ||||||||||||||
Power derivative contracts(c) | (67 | ) | 27 | (94 | ) | |||||||||||||||
Uranium derivative contracts(d) | (5 | ) | (5 | ) | — | |||||||||||||||
2012 | ||||||||||||||||||||
Cumulative gains (losses) deferred in regulatory liabilities or assets: | ||||||||||||||||||||
Fuel oils derivative contracts(a) | $ | 4 | $ | 4 | $ | — | ||||||||||||||
Natural gas derivative contracts(b) | (107 | ) | (14 | ) | (93 | ) | ||||||||||||||
Power derivative contracts(c) | (99 | ) | 12 | (111 | ) | |||||||||||||||
Uranium derivative contracts(d) | (2 | ) | (2 | ) | — | |||||||||||||||
(a) | Represents net gains (losses) on fuel oils derivative contracts at Ameren Missouri. These contracts are a partial hedge of Ameren Missouri’s transportation costs for coal through October 2015 as of September 30, 2013. Current gains deferred as regulatory liabilities include $3 million and $3 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. Current losses deferred as regulatory assets include $1 million and $1 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. | |||||||||||||||||||
(b) | Represents net losses associated with natural gas derivative contracts. These contracts are a partial hedge of natural gas requirements through October 2019 at Ameren and Ameren Missouri and through March 2017 at Ameren Illinois as of September 30, 2013. Current gains deferred as regulatory liabilities include $1 million, and $1 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. Current losses deferred as regulatory assets include $45 million, $7 million, and $38 million at Ameren, Ameren Missouri and Ameren Illinois, respectively, as of September 30, 2013. | |||||||||||||||||||
(c) | Represents net gains (losses) associated with power derivative contracts. These contracts are a partial hedge of power price requirements through May 2032 at Ameren and Ameren Illinois and through December 2015 at Ameren Missouri as of September 30, 2013. Current gains deferred as regulatory liabilities include $29 million and $29 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. Current losses deferred as regulatory assets include $13 million, $3 million, and $10 million at Ameren, Ameren Missouri and Ameren Illinois, respectively, as of September 30, 2013. | |||||||||||||||||||
(d) | Represents net losses on uranium derivative contracts at Ameren Missouri. These contracts are a partial hedge of Ameren Missouri’s uranium requirements through October 2016 as of September 30, 2013. Current gains deferred as regulatory liabilities included $1 million and $1 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. Current losses deferred as regulatory assets include $4 million and $4 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. | |||||||||||||||||||
Derivative instruments are subject to various credit-related losses in the event of nonperformance by counterparties to the transaction. Exchange-traded contracts are supported by the financial and credit quality of the clearing members of the respective exchanges and have nominal credit risk. In all other transactions, we are exposed to credit risk. Our credit risk management program involves establishing credit limits and collateral requirements for counterparties, using master trading and netting agreements, and reporting daily exposure to senior management. | ||||||||||||||||||||
We believe that entering into master trading and netting agreements mitigates the level of financial loss that could result from default by allowing net settlement of derivative assets and liabilities. We generally enter into the following master trading and netting agreements: (1) the International Swaps and Derivatives Association Agreement, a standardized financial natural gas and electric contract; (2) the Master Power Purchase and Sale Agreement, created by the Edison Electric Institute and the National Energy Marketers Association, a standardized contract for the purchase and sale of wholesale power; and (3) the North American Energy Standards Board Inc. agreement, a standardized contract for the purchase and sale of natural gas. These master trading and netting agreements allow the counterparties to net settle sale and purchase transactions. Further, collateral requirements are calculated at a master trading and netting agreement level by counterparty. | ||||||||||||||||||||
Although Ameren had not previously elected to offset fair value amounts and collateral for derivative instruments executed with the same counterparty under the same master netting arrangement, authoritative accounting guidance, effective in the first quarter 2013, requires those amounts eligible to be offset to be presented both at the gross and net amounts. The following table provides the recognized gross derivative balances and the net amounts of those derivatives subject to an enforceable master netting arrangement or similar agreement as of September 30, 2013, and December 31, 2012: | ||||||||||||||||||||
Gross Amounts Not Offset in the Balance Sheet | ||||||||||||||||||||
Gross Amounts Recognized in the Balance Sheet | Derivative Instruments | Cash Collateral Received/Posted(a) | Net | |||||||||||||||||
Amount | ||||||||||||||||||||
2013 | ||||||||||||||||||||
Commodity contracts eligible to be offset: | ||||||||||||||||||||
Assets: | ||||||||||||||||||||
Ameren | $ | 41 | $ | 11 | $ | — | $ | 30 | ||||||||||||
Ameren Missouri | 41 | 11 | — | 30 | ||||||||||||||||
Ameren Illinois | — | — | — | — | ||||||||||||||||
Liabilities: | ||||||||||||||||||||
Ameren | $ | 182 | $ | 11 | $ | 32 | $ | 139 | ||||||||||||
Ameren Missouri | 26 | 11 | 8 | 7 | ||||||||||||||||
Ameren Illinois | 156 | — | 24 | 132 | ||||||||||||||||
2012 | ||||||||||||||||||||
Commodity contracts eligible to be offset: | ||||||||||||||||||||
Assets: | ||||||||||||||||||||
Ameren | $ | 29 | $ | 10 | $ | — | $ | 19 | ||||||||||||
Ameren Missouri | 28 | 9 | — | 19 | ||||||||||||||||
Ameren Illinois | 1 | 1 | — | — | ||||||||||||||||
Liabilities: | ||||||||||||||||||||
Ameren | $ | 230 | $ | 10 | $ | 65 | $ | 155 | ||||||||||||
Ameren Missouri | 25 | 9 | 7 | 9 | ||||||||||||||||
Ameren Illinois | 205 | 1 | 58 | 146 | ||||||||||||||||
(a) | Cash collateral received reduces gross asset balances and is included in “Other current liabilities” and “Other deferred credits and liabilities” on the balance sheet. Cash collateral posted reduces gross liability balances and is included in “Other current assets” and “Other assets” on the balance sheet. | |||||||||||||||||||
Concentrations of Credit Risk | ||||||||||||||||||||
In determining our concentrations of credit risk related to derivative instruments, we review our individual counterparties and categorize each counterparty into groupings according to the primary business in which each engages. The following table presents the maximum exposure, as of September 30, 2013, and December 31, 2012, if counterparty groups were to fail completely to perform on contracts by grouping. The maximum exposure is based on the gross fair value of financial instruments, including accrual and NPNS contracts, which excludes collateral held, and does not consider the legally binding right to net transactions based on master trading and netting agreements. | ||||||||||||||||||||
Commodity | Electric | Financial | Municipalities/ | Total | ||||||||||||||||
Marketing | Utilities | Companies | Cooperatives | |||||||||||||||||
Companies | ||||||||||||||||||||
2013 | ||||||||||||||||||||
Ameren Missouri | $ | 1 | $ | 1 | $ | 7 | $ | 2 | $ | 11 | ||||||||||
Ameren Illinois | — | — | — | — | — | |||||||||||||||
Ameren | $ | 1 | $ | 1 | $ | 7 | $ | 2 | $ | 11 | ||||||||||
2012 | ||||||||||||||||||||
Ameren Missouri | $ | 2 | $ | 3 | $ | 14 | $ | 3 | $ | 22 | ||||||||||
Ameren Illinois | — | — | 1 | — | 1 | |||||||||||||||
Ameren | $ | 2 | $ | 3 | $ | 15 | $ | 3 | $ | 23 | ||||||||||
The potential loss on counterparty exposures is reduced by the application of master trading and netting agreements and collateral held to the extent of reducing the exposure to zero. Collateral includes both cash and other collateral held. The Ameren Companies held no cash from counterparties based on the contractual rights under the agreements to seek collateral and the maximum exposure as calculated under the individual master trading and netting agreements as of September 30, 2013, and December 31, 2012. As of September 30, 2013, no other collateral used to reduce exposure was held by the Ameren Companies. As of December 31, 2012, other collateral used to reduce exposure consisted of letters of credit of $1 million held by Ameren and Ameren Missouri. | ||||||||||||||||||||
The following table presents the potential loss after consideration of collateral and application of master trading and netting agreements as of September 30, 2013, and December 31, 2012: | ||||||||||||||||||||
Commodity | Electric | Financial | Municipalities/ | Total | ||||||||||||||||
Marketing | Utilities | Companies | Cooperatives | |||||||||||||||||
Companies | ||||||||||||||||||||
2013 | ||||||||||||||||||||
Ameren Missouri | $ | 1 | $ | — | $ | 2 | $ | 2 | $ | 5 | ||||||||||
Ameren Illinois | — | — | — | — | — | |||||||||||||||
Ameren | $ | 1 | $ | — | $ | 2 | $ | 2 | $ | 5 | ||||||||||
2012 | ||||||||||||||||||||
Ameren Missouri | $ | 1 | $ | 1 | $ | 10 | $ | 3 | $ | 15 | ||||||||||
Ameren Illinois | — | — | — | — | — | |||||||||||||||
Ameren | $ | 1 | $ | 1 | $ | 10 | $ | 3 | $ | 15 | ||||||||||
Derivative Instruments with Credit Risk-Related Contingent Features | ||||||||||||||||||||
Our commodity contracts contain collateral provisions tied to the Ameren Companies’ credit ratings. If we were to experience an adverse change in our credit ratings, or if a counterparty with reasonable grounds for uncertainty regarding performance of an obligation requested adequate assurance of performance, additional collateral postings might be required. The following table presents, as of September 30, 2013, and December 31, 2012, the aggregate fair value of all derivative instruments with credit risk-related contingent features in a gross liability position, the cash collateral posted, and the aggregate amount of additional collateral that could be required to be posted with counterparties. The additional collateral required is the net liability position allowed under the master trading and netting agreements, assuming (1) the credit risk-related contingent features underlying these agreements were triggered on September 30, 2013, or December 31, 2012, respectively, and (2) those counterparties with rights to do so requested collateral: | ||||||||||||||||||||
Aggregate Fair Value of | Cash | Potential Aggregate Amount of | ||||||||||||||||||
Derivative Liabilities(a) | Collateral Posted | Additional Collateral Required(b) | ||||||||||||||||||
2013 | ||||||||||||||||||||
Ameren Missouri | $ | 69 | $ | 1 | $ | 63 | ||||||||||||||
Ameren Illinois | 101 | 24 | 70 | |||||||||||||||||
Ameren | $ | 170 | $ | 25 | $ | 133 | ||||||||||||||
2012 | ||||||||||||||||||||
Ameren Missouri | $ | 78 | $ | 3 | $ | 71 | ||||||||||||||
Ameren Illinois | 148 | 58 | 84 | |||||||||||||||||
Ameren | $ | 226 | $ | 61 | $ | 155 | ||||||||||||||
(a) | Prior to consideration of master trading and netting agreements and including NPNS contract exposures. | |||||||||||||||||||
(b) | As collateral requirements with certain counterparties are based on master trading and netting agreements, the aggregate amount of additional collateral required to be posted is determined after consideration of the netting effects of such agreements. | |||||||||||||||||||
Derivatives that Qualify for Regulatory Deferral | ||||||||||||||||||||
The following table represents the net change in market value for derivatives that qualify for regulatory deferral for the three and nine months ended September 30, 2013, and 2012: | ||||||||||||||||||||
Gain (Loss) Recognized in Regulatory Liabilities or Regulatory Assets | ||||||||||||||||||||
Three Months | Nine Months | |||||||||||||||||||
2013 | 2012 | 2013 | 2012 | |||||||||||||||||
Ameren | Fuel oils | $ | 1 | $ | 5 | $ | (3 | ) | $ | (9 | ) | |||||||||
Natural gas | 9 | 46 | 33 | 74 | ||||||||||||||||
Power(a) | (24 | ) | (6 | ) | 32 | (169 | ) | |||||||||||||
Uranium | (2 | ) | (1 | ) | (3 | ) | (1 | ) | ||||||||||||
Total | $ | (16 | ) | $ | 44 | $ | 59 | $ | (105 | ) | ||||||||||
Ameren Missouri | Fuel oils | $ | 1 | $ | 5 | $ | (3 | ) | $ | (9 | ) | |||||||||
Natural gas | — | 6 | 2 | 9 | ||||||||||||||||
Power | (10 | ) | (6 | ) | 15 | (3 | ) | |||||||||||||
Uranium | (2 | ) | (1 | ) | (3 | ) | (1 | ) | ||||||||||||
Total | $ | (11 | ) | $ | 4 | $ | 11 | $ | (4 | ) | ||||||||||
Ameren Illinois | Natural gas | $ | 9 | $ | 40 | $ | 31 | $ | 65 | |||||||||||
Power | (14 | ) | 56 | 17 | (25 | ) | ||||||||||||||
Total | $ | (5 | ) | $ | 96 | $ | 48 | $ | 40 | |||||||||||
(a) | Amounts include intercompany eliminations. |
Fair_Value_Measurements
Fair Value Measurements | 9 Months Ended | |||||||||||||||||
Sep. 30, 2013 | ||||||||||||||||||
Fair Value Disclosures [Abstract] | ' | |||||||||||||||||
FAIR VALUE MEASUREMENTS | ' | |||||||||||||||||
FAIR VALUE MEASUREMENTS | ||||||||||||||||||
Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. We use various methods to determine fair value, including market, income, and cost approaches. With these approaches, we adopt certain assumptions that market participants would use in pricing the asset or liability, including assumptions about market risk or the risks inherent in the inputs to the valuation. Inputs to valuation can be readily observable, market-corroborated, or unobservable. We use valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs. Authoritative accounting guidance established a fair value hierarchy that prioritizes the inputs used to measure fair value. All financial assets and liabilities carried at fair value are classified and disclosed in one of the following three hierarchy levels: | ||||||||||||||||||
Level 1: Inputs based on quoted prices in active markets for identical assets or liabilities. Level 1 assets and liabilities are primarily exchange-traded derivatives and assets, including cash and cash equivalents and listed equity securities, such as those held in Ameren Missouri’s Nuclear Decommissioning Trust Fund. | ||||||||||||||||||
The market approach is used to measure the fair value of equity securities held in Ameren Missouri’s Nuclear Decommissioning Trust Fund. Equity securities in this fund are representative of the S&P 500 index, excluding securities of Ameren Corporation, owners and/or operators of nuclear power plants and the trustee and investment managers. The S&P 500 index is comprised of stocks of large capitalization companies. | ||||||||||||||||||
Level 2: Market-based inputs corroborated by third-party brokers or exchanges based on transacted market data. Level 2 assets and liabilities include certain assets held in Ameren Missouri’s Nuclear Decommissioning Trust Fund, including corporate bonds and other fixed-income securities, United States treasury and agency securities, and certain over-the-counter derivative instruments, including natural gas and financial power transactions. | ||||||||||||||||||
Fixed income securities are valued using prices from independent, industry recognized data vendors who provide values that are either exchange based or matrix based. The fair value measurements of fixed income securities classified as Level 2 are based on inputs other than quoted prices that are observable for the asset or liability. Examples are matrix pricing, market-corroborated pricing, and inputs such as yield curves and indices. Level 2 fixed income securities in the Nuclear Decommissioning Trust Fund are comprised primarily of corporate bonds, asset-backed securities and United States agency bonds. | ||||||||||||||||||
Derivative instruments classified as Level 2 are valued by corroborated observable inputs, such as pricing services or prices from similar instruments that trade in liquid markets. Our development and corroboration process entails obtaining multiple quotes or prices from outside sources. To derive our forward view to price our derivative instruments at fair value, we average the midpoints of the bid/ask spreads. To validate forward prices obtained from outside parties, we compare the pricing to recently settled market transactions. Additionally, a review of all sources is performed to identify any anomalies or potential errors. Further, we consider the volume of transactions on certain trading platforms in our reasonableness assessment of the averaged midpoint. Natural gas derivative contracts are valued based upon exchange closing prices without significant unobservable adjustments. Power derivative contracts are valued based upon the use of multiple forward prices provided by third parties. The prices are averaged and shaped to a monthly profile when needed without significant unobservable adjustments. | ||||||||||||||||||
Level 3: Unobservable inputs that are not corroborated by market data. Level 3 assets and liabilities are valued by internally developed models and assumptions or methodologies that use significant unobservable inputs. Level 3 assets and liabilities include derivative instruments that trade in less liquid markets, where pricing is largely unobservable. We value Level 3 instruments by using pricing models with inputs that are often unobservable in the market, as well as certain internal assumptions. Our development and corroboration process entails obtaining multiple quotes or prices from outside sources. As a part of our fair value estimation process, an evaluation of all sources is performed to identify any anomalies or potential errors. | ||||||||||||||||||
We perform an analysis each quarter to determine the appropriate hierarchy level of the assets and liabilities subject to fair value measurements. Financial assets and liabilities are classified in their entirety according to the lowest level of input that is significant to the fair value measurement. All assets and liabilities whose fair value measurement is based on significant unobservable inputs are classified as Level 3. | ||||||||||||||||||
The following table describes the valuation techniques and unobservable inputs for the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy as of September 30, 2013: | ||||||||||||||||||
Fair Value | Weighted | |||||||||||||||||
Assets | Liabilities | Valuation Technique | Unobservable Input | Range | Average | |||||||||||||
Level 3 Derivative asset and liability - commodity contracts(a): | ||||||||||||||||||
Ameren | Fuel oils | $ | 7 | $ | (4 | ) | Option model | Volatilities(%)(b) | 20-Sep | 17 | ||||||||
Discounted cash flow | Counterparty credit risk(%)(c)(d) | .26 - 3 | 2 | |||||||||||||||
Natural gas | 1 | (1 | ) | Option model | Volatilities(%)(b) | 29-May | 24 | |||||||||||
Nodal basis($/mmbtu)(c) | (0.40) - (0.20) | -0.4 | ||||||||||||||||
Discounted cash flow | Nodal basis($/mmbtu)(c) | -0.1 | (e) | |||||||||||||||
Counterparty credit risk(%)(c)(d) | 0.64 - 0.83 | 0.77 | ||||||||||||||||
Ameren credit risk(%)(c)(d) | 3-Feb | 2 | ||||||||||||||||
Power(f) | 29 | (95 | ) | Discounted cash flow | Average forward peak and off-peak power pricing - forwards/swaps($/MWh)(c) | 27 - 43 | 30 | |||||||||||
Estimated auction price for FTRs($/MW)(b) | (103) - 1790 | 660 | ||||||||||||||||
Nodal basis($/MWh)(c) | (5) - (1) | -3 | ||||||||||||||||
Counterparty credit risk(%)(c)(d) | 0.22 - 3 | 0.73 | ||||||||||||||||
Ameren credit risk(%)(c)(d) | 3 | (e) | ||||||||||||||||
Fundamental energy production model | Estimated future gas prices($/mmbtu)(b) | 7-Apr | 5 | |||||||||||||||
Escalation rate(%)(b)(g) | 5-Apr | 4 | ||||||||||||||||
Contract price allocation | Estimated renewable energy credit costs($/credit)(b) | 7-May | 6 | |||||||||||||||
Uranium | 1 | (6 | ) | Discounted cash flow | Average forward uranium pricing($/pound)(b) | 35 - 43 | 36 | |||||||||||
Ameren Missouri | Fuel oils | $ | 7 | $ | (4 | ) | Option model | Volatilities(%)(b) | 20-Sep | 17 | ||||||||
Discounted cash flow | Counterparty credit risk(%)(c)(d) | .26 - 3 | 2 | |||||||||||||||
Natural gas | 1 | (1 | ) | Option model | Volatilities(%)(b) | 29-May | 24 | |||||||||||
Nodal basis($/mmbtu)(c) | (0.40) - (0.20) | -0.4 | ||||||||||||||||
Discounted cash flow | Nodal basis($/mmbtu)(c) | -0.1 | (e) | |||||||||||||||
Counterparty credit risk(%)(c)(d) | 0.64 - 0.83 | 0.77 | ||||||||||||||||
Ameren Missouri credit risk(%)(c)(d) | 3-Feb | 2 | ||||||||||||||||
Power(f) | 29 | (1 | ) | Discounted cash flow | Average forward peak and off-peak power pricing - forwards/swaps($/MWh)(c) | 27 - 43 | 33 | |||||||||||
Estimated auction price for FTRs($/MW)(b) | (103) - 1790 | 660 | ||||||||||||||||
Nodal basis($/MWh)(c) | (4) - (1) | -4 | ||||||||||||||||
Counterparty credit risk(%)(c)(d) | 0.22 - 3 | 0.73 | ||||||||||||||||
Ameren Missouri credit risk(%)(c)(d) | 3 | (e) | ||||||||||||||||
Uranium | 1 | (6 | ) | Discounted cash flow | Average forward uranium pricing($/pound)(b) | 35 - 43 | 36 | |||||||||||
Ameren Illinois | Power(f) | $ | — | $ | (94 | ) | Discounted cash flow | Average forward peak and off-peak power pricing - forwards/swaps($/MWh)(b) | 27 - 37 | 30 | ||||||||
Nodal basis($/MWh)(b) | (5) - (1) | -3 | ||||||||||||||||
Ameren Illinois credit risk(%)(c)(d) | 3 | (e) | ||||||||||||||||
Fundamental energy production model | Estimated future gas prices($/mmbtu)(b) | 7-Apr | 5 | |||||||||||||||
Escalation rate(%)(b)(g) | 5-Apr | 4 | ||||||||||||||||
Contract price allocation | Estimated renewable energy credit costs($/credit)(b) | 7-May | 6 | |||||||||||||||
(a) | The derivative asset and liability balances are presented net of counterparty credit considerations. | |||||||||||||||||
(b) | Generally, significant increases (decreases) in this input in isolation would result in a significantly higher (lower) fair value measurement. | |||||||||||||||||
(c) | Generally, significant increases (decreases) in this input in isolation would result in a significantly lower (higher) fair value measurement. | |||||||||||||||||
(d) | Counterparty credit risk is only applied to counterparties with derivative asset balances. Ameren, Ameren Missouri, and Ameren Illinois credit risk is only applied to counterparties with derivative liability balances. | |||||||||||||||||
(e) | Not applicable. | |||||||||||||||||
(f) | Power valuations utilize visible third-party pricing evaluated by month for peak and off-peak demand through 2017. Valuations beyond 2017 utilize fundamentally modeled pricing by month for peak and off-peak demand. | |||||||||||||||||
(g) | Escalation rate applies to power prices 2026 and beyond. | |||||||||||||||||
The following table describes the valuation techniques and unobservable inputs for the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy as of December 31, 2012: | ||||||||||||||||||
Fair Value | Weighted | |||||||||||||||||
Assets | Liabilities | Valuation Technique | Unobservable Input | Range | Average | |||||||||||||
Level 3 Derivative asset and liability - commodity contracts(a): | ||||||||||||||||||
Ameren | Fuel oils | $ | 8 | $ | (3 | ) | Discounted cash flow | Escalation rate(%)(b) | .21 - .60 | 0.44 | ||||||||
Counterparty credit risk(%)(c)(d) | .12 - 1 | 1 | ||||||||||||||||
Ameren credit risk(%)(c)(d) | 2 | (e) | ||||||||||||||||
Option model | Volatilities(%)(b) | 27-Jul | 24 | |||||||||||||||
Power(f) | 14 | (114 | ) | Discounted cash flow | Average forward peak and off-peak power pricing - forwards/swaps($/MWh)(c) | 22 - 47 | 31 | |||||||||||
Estimated auction price for FTRs($/MW)(b) | (281) - 1,851 | 178 | ||||||||||||||||
Nodal basis($/MWh)(c) | (5) - (1) | -3 | ||||||||||||||||
Counterparty credit risk(%)(c)(d) | .22 - 1 | 1 | ||||||||||||||||
Ameren credit risk(%)(c)(d) | 5-Feb | 5 | ||||||||||||||||
Fundamental energy production model | Estimated future gas prices($/mmbtu)(b) | 8-Apr | 6 | |||||||||||||||
Contract price allocation | Estimated renewable energy credit costs($/credit)(b) | 7-May | 6 | |||||||||||||||
Uranium | — | (2 | ) | Discounted cash flow | Average forward uranium pricing($/pound)(b) | 43 - 46 | 44 | |||||||||||
Ameren Missouri | Fuel oils | $ | 8 | $ | (3 | ) | Discounted cash flow | Escalation rate(%)(b) | .21 - .60 | 0.44 | ||||||||
Counterparty credit risk(%)(c)(d) | .12 - 1 | 1 | ||||||||||||||||
Ameren Missouri credit risk(%)(c)(d) | 2 | (e) | ||||||||||||||||
Option model | Volatilities(%)(b) | 27-Jul | 24 | |||||||||||||||
Power(f) | 14 | (3 | ) | Discounted cash flow | Average forward peak and off-peak power pricing - forwards/swaps($/MWh)(c) | 24 - 56 | 36 | |||||||||||
Estimated auction price for FTRs($/MW)(b) | (281) - 1,851 | 178 | ||||||||||||||||
Nodal basis($/MWh)(c) | (5) - (1) | -2 | ||||||||||||||||
Counterparty credit risk(%)(c)(d) | .22 - 1 | 1 | ||||||||||||||||
Ameren Missouri credit risk(%)(c)(d) | 2 | (e) | ||||||||||||||||
Uranium | — | (2 | ) | Discounted cash flow | Average forward uranium pricing($/pound)(b) | 43 - 46 | 44 | |||||||||||
Ameren Illinois | Power(f) | $ | — | $ | (111 | ) | Discounted cash flow | Average forward peak and off-peak power pricing - forwards/swaps($/MWh)(b) | 22 - 47 | 30 | ||||||||
Nodal basis($/MWh)(b) | (5) - (1) | -3 | ||||||||||||||||
Ameren Illinois credit risk(%)(c)(d) | 5 | (e) | ||||||||||||||||
Fundamental energy production model | Estimated future gas prices($/mmbtu)(b) | 8-Apr | 6 | |||||||||||||||
Contract price allocation | Estimated renewable energy credit costs($/credit)(b) | 7-May | 6 | |||||||||||||||
(a) | The derivative asset and liability balances are presented net of counterparty credit considerations. | |||||||||||||||||
(b) | Generally, significant increases (decreases) in this input in isolation would result in a significantly higher (lower) fair value measurement. | |||||||||||||||||
(c) | Generally, significant increases (decreases) in this input in isolation would result in a significantly lower (higher) fair value measurement. | |||||||||||||||||
(d) | Counterparty credit risk is only applied to counterparties with derivative asset balances. Ameren, Ameren Missouri, and Ameren Illinois credit risk is only applied to counterparties with derivative liability balances. | |||||||||||||||||
(e) | Not applicable. | |||||||||||||||||
(f) | Power valuations utilize visible third-party pricing evaluated by month for peak and off-peak demand through 2017. Valuations beyond 2017 utilize fundamentally modeled pricing by month for peak and off-peak demand. | |||||||||||||||||
In accordance with applicable authoritative accounting guidance, we consider nonperformance risk in our valuation of derivative instruments by analyzing the credit standing of our counterparties and considering any counterparty credit enhancements (e.g., collateral). The guidance also requires that the fair value measurement of liabilities reflect the nonperformance risk of the reporting entity, as applicable. Therefore, we have factored the impact of our credit standing as well as any potential credit enhancements into the fair value measurement of both derivative assets and derivative liabilities. Included in our valuation, and based on current market conditions, is a valuation adjustment for counterparty default derived from market data such as the price of credit default swaps, bond yields, and credit ratings. Ameren recorded no gains or losses in the first nine months of 2013 or 2012 related to valuation adjustments for counterparty default risk. At September 30, 2013, the counterparty default risk liability valuation adjustment related to derivative contracts totaled $4 million, less than $1 million, and $4 million, for Ameren, Ameren Missouri, and Ameren Illinois, respectively. At December 31, 2012, the counterparty default risk liability valuation adjustment related to derivative contracts totaled $7 million, less than $1 million, and $7 million, for Ameren, Ameren Missouri, and Ameren Illinois, respectively. | ||||||||||||||||||
The following table sets forth, by level within the fair value hierarchy, our assets and liabilities measured at fair value on a recurring basis as of September 30, 2013: | ||||||||||||||||||
Quoted Prices in | Significant Other | Significant Other | Total | |||||||||||||||
Active Markets for | Observable Inputs | Unobservable | ||||||||||||||||
Identical Assets | (Level 2) | Inputs | ||||||||||||||||
or Liabilities | (Level 3) | |||||||||||||||||
(Level 1) | ||||||||||||||||||
Assets: | ||||||||||||||||||
Ameren | Derivative assets - commodity contracts(a): | |||||||||||||||||
Fuel oils | $ | 1 | $ | — | $ | 7 | $ | 8 | ||||||||||
Natural gas | — | — | 1 | 1 | ||||||||||||||
Power | — | 2 | 29 | 31 | ||||||||||||||
Uranium | — | — | 1 | 1 | ||||||||||||||
Total derivative assets - commodity contracts | $ | 1 | $ | 2 | $ | 38 | $ | 41 | ||||||||||
Nuclear Decommissioning Trust Fund(b): | ||||||||||||||||||
Cash and cash equivalents | $ | 2 | $ | — | $ | — | $ | 2 | ||||||||||
Equity securities: | ||||||||||||||||||
U.S. large capitalization | 309 | — | — | 309 | ||||||||||||||
Debt securities: | ||||||||||||||||||
Corporate bonds | — | 45 | — | 45 | ||||||||||||||
Municipal bonds | — | 2 | — | 2 | ||||||||||||||
U.S. treasury and agency securities | — | 90 | — | 90 | ||||||||||||||
Asset-backed securities | — | 9 | — | 9 | ||||||||||||||
Other | — | 1 | — | 1 | ||||||||||||||
Total Nuclear Decommissioning Trust Fund | $ | 311 | $ | 147 | $ | — | $ | 458 | ||||||||||
Total Ameren | $ | 312 | $ | 149 | $ | 38 | $ | 499 | ||||||||||
Ameren | Derivative assets - commodity contracts(a): | |||||||||||||||||
Missouri | Fuel oils | $ | 1 | $ | — | $ | 7 | $ | 8 | |||||||||
Natural gas | — | — | 1 | 1 | ||||||||||||||
Power | — | 2 | 29 | 31 | ||||||||||||||
Uranium | — | — | 1 | 1 | ||||||||||||||
Total derivative assets - commodity contracts | $ | 1 | $ | 2 | $ | 38 | $ | 41 | ||||||||||
Nuclear Decommissioning Trust Fund(b): | ||||||||||||||||||
Cash and cash equivalents | $ | 2 | $ | — | $ | — | $ | 2 | ||||||||||
Equity securities: | ||||||||||||||||||
U.S. large capitalization | 309 | — | — | 309 | ||||||||||||||
Debt securities: | ||||||||||||||||||
Corporate bonds | — | 45 | — | 45 | ||||||||||||||
Municipal bonds | — | 2 | — | 2 | ||||||||||||||
U.S. treasury and agency securities | — | 90 | — | 90 | ||||||||||||||
Asset-backed securities | — | 9 | — | 9 | ||||||||||||||
Other | — | 1 | — | 1 | ||||||||||||||
Total Nuclear Decommissioning Trust Fund | $ | 311 | $ | 147 | $ | — | $ | 458 | ||||||||||
Total Ameren Missouri | $ | 312 | $ | 149 | $ | 38 | $ | 499 | ||||||||||
Liabilities: | ||||||||||||||||||
Ameren | Derivative liabilities - commodity contracts(a): | |||||||||||||||||
Fuel oils | $ | — | $ | — | $ | 4 | $ | 4 | ||||||||||
Natural gas | 5 | 69 | 1 | 75 | ||||||||||||||
Power | — | 2 | 95 | 97 | ||||||||||||||
Uranium | — | — | 6 | 6 | ||||||||||||||
Total Ameren | $ | 5 | $ | 71 | $ | 106 | $ | 182 | ||||||||||
Ameren | Derivative liabilities - commodity contracts(a): | |||||||||||||||||
Missouri | Fuel oils | $ | — | $ | — | $ | 4 | $ | 4 | |||||||||
Natural gas | 5 | 7 | 1 | 13 | ||||||||||||||
Power | — | 2 | 1 | 3 | ||||||||||||||
Uranium | — | — | 6 | 6 | ||||||||||||||
Total Ameren Missouri | $ | 5 | $ | 9 | $ | 12 | $ | 26 | ||||||||||
Ameren | Derivative liabilities - commodity contracts(a): | |||||||||||||||||
Illinois | Natural gas | $ | — | $ | 62 | $ | — | $ | 62 | |||||||||
Power | — | — | 94 | 94 | ||||||||||||||
Total Ameren Illinois | $ | — | $ | 62 | $ | 94 | $ | 156 | ||||||||||
(a) | The derivative asset and liability balances are presented net of counterparty credit considerations. | |||||||||||||||||
(b) | Balance excludes $1 million of receivables, payables, and accrued income, net. | |||||||||||||||||
The following table sets forth, by level within the fair value hierarchy, our assets and liabilities measured at fair value on a recurring basis as of December 31, 2012: | ||||||||||||||||||
Quoted Prices in | Significant Other | Significant Other | Total | |||||||||||||||
Active Markets for | Observable Inputs | Unobservable | ||||||||||||||||
Identical Assets | (Level 2) | Inputs | ||||||||||||||||
or Liabilities | (Level 3) | |||||||||||||||||
(Level 1) | ||||||||||||||||||
Assets: | ||||||||||||||||||
Ameren | Derivative assets - commodity contracts(a): | |||||||||||||||||
Fuel oils | $ | 4 | $ | — | $ | 8 | $ | 12 | ||||||||||
Natural gas | — | 2 | — | 2 | ||||||||||||||
Power | — | 1 | 14 | 15 | ||||||||||||||
Total derivative assets - commodity contracts | $ | 4 | $ | 3 | $ | 22 | $ | 29 | ||||||||||
Nuclear Decommissioning Trust Fund(b): | ||||||||||||||||||
Cash and cash equivalents | $ | 1 | $ | — | $ | — | $ | 1 | ||||||||||
Equity securities: | ||||||||||||||||||
U.S. large capitalization | 264 | — | — | 264 | ||||||||||||||
Debt securities: | ||||||||||||||||||
Corporate bonds | — | 47 | — | 47 | ||||||||||||||
Municipal bonds | — | 1 | — | 1 | ||||||||||||||
U.S. treasury and agency securities | — | 81 | — | 81 | ||||||||||||||
Asset-backed securities | — | 11 | — | 11 | ||||||||||||||
Other | — | 1 | — | 1 | ||||||||||||||
Total Nuclear Decommissioning Trust Fund | $ | 265 | $ | 141 | $ | — | $ | 406 | ||||||||||
Total Ameren | $ | 269 | $ | 144 | $ | 22 | $ | 435 | ||||||||||
Ameren | Derivative assets - commodity contracts(a): | |||||||||||||||||
Missouri | Fuel oils | $ | 4 | $ | — | $ | 8 | $ | 12 | |||||||||
Natural gas | — | 1 | — | 1 | ||||||||||||||
Power | — | 1 | 14 | 15 | ||||||||||||||
Total derivative assets - commodity contracts | $ | 4 | $ | 2 | $ | 22 | $ | 28 | ||||||||||
Nuclear Decommissioning Trust Fund(b): | ||||||||||||||||||
Cash and cash equivalents | $ | 1 | $ | — | $ | — | $ | 1 | ||||||||||
Equity securities: | ||||||||||||||||||
U.S. large capitalization | 264 | — | — | 264 | ||||||||||||||
Debt securities: | ||||||||||||||||||
Corporate bonds | — | 47 | — | 47 | ||||||||||||||
Municipal bonds | — | 1 | — | 1 | ||||||||||||||
U.S. treasury and agency securities | — | 81 | — | 81 | ||||||||||||||
Asset-backed securities | — | 11 | — | 11 | ||||||||||||||
Other | — | 1 | — | 1 | ||||||||||||||
Total Nuclear Decommissioning Trust Fund | $ | 265 | $ | 141 | $ | — | $ | 406 | ||||||||||
Total Ameren Missouri | $ | 269 | $ | 143 | $ | 22 | $ | 434 | ||||||||||
Ameren | Derivative assets - commodity contracts(a): | |||||||||||||||||
Illinois | Natural gas | $ | — | $ | 1 | $ | — | $ | 1 | |||||||||
Quoted Prices in | Significant Other | Significant Other | Total | |||||||||||||||
Active Markets for | Observable Inputs | Unobservable | ||||||||||||||||
Identical Assets | (Level 2) | Inputs | ||||||||||||||||
or Liabilities | (Level 3) | |||||||||||||||||
(Level 1) | ||||||||||||||||||
Liabilities: | ||||||||||||||||||
Ameren | Derivative liabilities - commodity contracts(a): | |||||||||||||||||
Fuel oils | $ | 1 | $ | — | $ | 3 | $ | 4 | ||||||||||
Natural gas | 7 | 102 | — | 109 | ||||||||||||||
Power | — | 1 | 114 | 115 | ||||||||||||||
Uranium | — | — | 2 | 2 | ||||||||||||||
Total Ameren | $ | 8 | $ | 103 | $ | 119 | $ | 230 | ||||||||||
Ameren | Derivative liabilities - commodity contracts(a): | |||||||||||||||||
Missouri | Fuel oils | $ | 1 | $ | — | $ | 3 | $ | 4 | |||||||||
Natural gas | 7 | 8 | — | 15 | ||||||||||||||
Power | — | 1 | 3 | 4 | ||||||||||||||
Uranium | — | — | 2 | 2 | ||||||||||||||
Total Ameren Missouri | $ | 8 | $ | 9 | $ | 8 | $ | 25 | ||||||||||
Ameren | Derivative liabilities - commodity contracts(a): | |||||||||||||||||
Illinois | Natural gas | $ | — | $ | 94 | $ | — | $ | 94 | |||||||||
Power | — | — | 111 | 111 | ||||||||||||||
Total Ameren Illinois | $ | — | $ | 94 | $ | 111 | $ | 205 | ||||||||||
(a) | The derivative asset and liability balances are presented net of counterparty credit considerations. | |||||||||||||||||
(b) | Balance excludes $2 million of receivables, payables, and accrued income, net. | |||||||||||||||||
The following table summarizes the changes in the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy for the three months ended September 30, 2013: | ||||||||||||||||||
Net derivative commodity contracts | ||||||||||||||||||
Three Months | Ameren | Ameren | Ameren | |||||||||||||||
Missouri | Illinois | |||||||||||||||||
Fuel oils: | ||||||||||||||||||
Beginning balance at July 1, 2013 | $ | 3 | $ | (a) | $ | 3 | ||||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | 1 | (a) | 1 | |||||||||||||||
Total realized and unrealized gains (losses) | 1 | (a) | 1 | |||||||||||||||
Purchases | 1 | (a) | 1 | |||||||||||||||
Sales | (1 | ) | (a) | (1 | ) | |||||||||||||
Settlements | (1 | ) | (a) | (1 | ) | |||||||||||||
Ending balance at September 30, 2013 | $ | 3 | $ | (a) | $ | 3 | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | 1 | $ | (a) | $ | 1 | ||||||||||||
Natural gas: | ||||||||||||||||||
Beginning balance at July 1, 2013 | $ | (1 | ) | $ | 2 | $ | 1 | |||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | — | (2 | ) | (2 | ) | |||||||||||||
Total realized and unrealized gains (losses) | — | (2 | ) | (2 | ) | |||||||||||||
Purchases | 1 | — | 1 | |||||||||||||||
Ending balance at September 30, 2013 | $ | — | $ | — | $ | — | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | — | $ | (1 | ) | $ | (1 | ) | ||||||||||
Power: | ||||||||||||||||||
Beginning balance at July 1, 2013 | $ | 37 | $ | (80 | ) | $ | (43 | ) | ||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (3 | ) | (17 | ) | (20 | ) | ||||||||||||
Total realized and unrealized gains (losses) | (3 | ) | (17 | ) | (20 | ) | ||||||||||||
Sales | 1 | — | 1 | |||||||||||||||
Settlements | (6 | ) | 3 | (3 | ) | |||||||||||||
Transfers into Level 3 | (1 | ) | — | (1 | ) | |||||||||||||
Ending balance at September 30, 2013 | $ | 28 | $ | (94 | ) | $ | (66 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | (2 | ) | $ | (16 | ) | $ | (18 | ) | |||||||||
Uranium: | ||||||||||||||||||
Beginning balance at July 1, 2013 | $ | (3 | ) | $ | (a) | $ | (3 | ) | ||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | — | (a) | — | |||||||||||||||
Total realized and unrealized gains (losses) | — | (a) | — | |||||||||||||||
Purchases | (2 | ) | (a) | (2 | ) | |||||||||||||
Ending balance at September 30, 2013 | $ | (5 | ) | $ | (a) | $ | (5 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | (2 | ) | $ | (a) | $ | (2 | ) | ||||||||||
(a) | Not applicable. | |||||||||||||||||
The following table summarizes the changes in the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy for the three months ended September 30, 2012: | ||||||||||||||||||
Net derivative commodity contracts | ||||||||||||||||||
Three Months | Ameren | Ameren | Ameren | |||||||||||||||
Missouri | Illinois | |||||||||||||||||
Fuel oils: | ||||||||||||||||||
Beginning balance at July 1, 2012 | $ | 3 | $ | (a) | $ | 3 | ||||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | 1 | (a) | 1 | |||||||||||||||
Total realized and unrealized gains (losses) | 1 | (a) | 1 | |||||||||||||||
Purchases | 2 | (a) | 2 | |||||||||||||||
Sales | (1 | ) | (a) | (1 | ) | |||||||||||||
Ending balance at September 30, 2012 | $ | 5 | $ | (a) | $ | 5 | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | 2 | $ | (a) | $ | 2 | ||||||||||||
Power(b): | ||||||||||||||||||
Beginning balance at July 1, 2012 | $ | 26 | $ | (221 | ) | $ | (81 | ) | ||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (4 | ) | 2 | (6 | ) | |||||||||||||
Total realized and unrealized gains (losses) | (4 | ) | 2 | (6 | ) | |||||||||||||
Sales | (1 | ) | — | (1 | ) | |||||||||||||
Settlements | (4 | ) | 54 | (1 | ) | |||||||||||||
Transfers out of Level 3 | (2 | ) | — | (2 | ) | |||||||||||||
Ending balance at September 30, 2012 | $ | 15 | $ | (165 | ) | $ | (91 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | (5 | ) | $ | (2 | ) | $ | (7 | ) | |||||||||
Uranium: | ||||||||||||||||||
Beginning balance at July 1, 2012 | $ | (1 | ) | (a) | $ | (1 | ) | |||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (1 | ) | (a) | (1 | ) | |||||||||||||
Total realized and unrealized gains (losses) | (1 | ) | (a) | (1 | ) | |||||||||||||
Ending balance at September 30, 2012 | $ | (2 | ) | (a) | $ | (2 | ) | |||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | (1 | ) | (a) | $ | (1 | ) | |||||||||||
(a) | Not applicable. | |||||||||||||||||
(b) | Ameren amounts include the elimination of financial power contracts between Ameren Illinois and Marketing Company. | |||||||||||||||||
The following table summarizes the changes in the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy for the nine months ended September 30, 2013: | ||||||||||||||||||
Net derivative commodity contracts | ||||||||||||||||||
Nine Months | Ameren | Ameren | Ameren | |||||||||||||||
Missouri | Illinois | |||||||||||||||||
Fuel oils: | ||||||||||||||||||
Beginning balance at January 1, 2013 | $ | 5 | $ | (a) | $ | 5 | ||||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (1 | ) | (a) | (1 | ) | |||||||||||||
Total realized and unrealized gains (losses) | (1 | ) | (a) | (1 | ) | |||||||||||||
Purchases | 2 | (a) | 2 | |||||||||||||||
Sales | (1 | ) | (a) | (1 | ) | |||||||||||||
Settlements | (2 | ) | (a) | (2 | ) | |||||||||||||
Ending balance at September 30, 2013 | $ | 3 | $ | (a) | $ | 3 | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | — | $ | (a) | $ | — | ||||||||||||
Natural gas: | ||||||||||||||||||
Beginning balance at January 1, 2013 | $ | — | $ | — | $ | — | ||||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | — | (1 | ) | (1 | ) | |||||||||||||
Total realized and unrealized gains (losses) | — | (1 | ) | (1 | ) | |||||||||||||
Purchases | — | 1 | 1 | |||||||||||||||
Ending balance at September 30, 2013 | $ | — | $ | — | $ | — | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | — | $ | — | $ | — | ||||||||||||
Power: | ||||||||||||||||||
Beginning balance at January 1, 2013 | $ | 11 | $ | (111 | ) | $ | (100 | ) | ||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | 3 | (2 | ) | 1 | ||||||||||||||
Total realized and unrealized gains (losses) | 3 | (2 | ) | 1 | ||||||||||||||
Purchases | 40 | — | 40 | |||||||||||||||
Sales | 1 | — | 1 | |||||||||||||||
Settlements | (28 | ) | 19 | (9 | ) | |||||||||||||
Transfers into Level 3 | (3 | ) | — | (3 | ) | |||||||||||||
Transfers out of Level 3 | 4 | — | 4 | |||||||||||||||
Ending balance at September 30, 2013 | $ | 28 | $ | (94 | ) | $ | (66 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | — | $ | (7 | ) | $ | (7 | ) | ||||||||||
Uranium: | ||||||||||||||||||
Beginning balance at January 1, 2013 | $ | (2 | ) | $ | (a) | $ | (2 | ) | ||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (2 | ) | (a) | (2 | ) | |||||||||||||
Total realized and unrealized gains (losses) | (2 | ) | (a) | (2 | ) | |||||||||||||
Purchases | (2 | ) | (a) | (2 | ) | |||||||||||||
Settlements | 1 | (a) | 1 | |||||||||||||||
Ending balance at September 30, 2013 | $ | (5 | ) | $ | (a) | $ | (5 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | (2 | ) | $ | (a) | $ | (2 | ) | ||||||||||
(a) | Not applicable. | |||||||||||||||||
The following table summarizes the changes in the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy for the nine months ended September 30, 2012: | ||||||||||||||||||
Net derivative commodity contracts | ||||||||||||||||||
Nine Months | Ameren | Ameren | Ameren | |||||||||||||||
Missouri | Illinois | |||||||||||||||||
Fuel oils: | ||||||||||||||||||
Beginning balance at January 1, 2012 | $ | 3 | $ | (a) | $ | 3 | ||||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (1 | ) | (a) | (1 | ) | |||||||||||||
Total realized and unrealized gains (losses) | (1 | ) | (a) | (1 | ) | |||||||||||||
Purchases | 4 | (a) | 4 | |||||||||||||||
Sales | (2 | ) | (a) | (2 | ) | |||||||||||||
Settlements | (1 | ) | (a) | (1 | ) | |||||||||||||
Transfers into Level 3 | 2 | (a) | 2 | |||||||||||||||
Ending balance at September 30, 2012 | $ | 5 | $ | (a) | $ | 5 | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | (1 | ) | $ | (a) | $ | (1 | ) | ||||||||||
Natural gas: | ||||||||||||||||||
Beginning balance at January 1, 2012 | $ | (14 | ) | $ | (160 | ) | $ | (174 | ) | |||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (2 | ) | (26 | ) | (28 | ) | ||||||||||||
Total realized and unrealized gains (losses) | (2 | ) | (26 | ) | (28 | ) | ||||||||||||
Settlements | 1 | 16 | 17 | |||||||||||||||
Transfers out of Level 3 | 15 | 170 | 185 | |||||||||||||||
Ending balance at September 30, 2012 | $ | — | $ | — | $ | — | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | 7 | $ | — | $ | 7 | ||||||||||||
Power(b): | ||||||||||||||||||
Beginning balance at January 1, 2012 | $ | 21 | $ | (140 | ) | $ | 81 | |||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | 5 | (219 | ) | (174 | ) | |||||||||||||
Total realized and unrealized gains (losses) | 5 | (219 | ) | (174 | ) | |||||||||||||
Purchases | 22 | — | 22 | |||||||||||||||
Sales | (1 | ) | — | (1 | ) | |||||||||||||
Settlements | (28 | ) | 194 | (15 | ) | |||||||||||||
Transfers out of Level 3 | (4 | ) | — | (4 | ) | |||||||||||||
Ending balance at September 30, 2012 | $ | 15 | $ | (165 | ) | $ | (91 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | (1 | ) | $ | (187 | ) | (c) $ | (171 | ) | |||||||||
Uranium: | ||||||||||||||||||
Beginning balance at January 1, 2012 | $ | (1 | ) | $ | (a) | $ | (1 | ) | ||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (1 | ) | (a) | (1 | ) | |||||||||||||
Total realized and unrealized gains (losses) | (1 | ) | (a) | (1 | ) | |||||||||||||
Ending balance at September 30, 2012 | $ | (2 | ) | $ | (a) | $ | (2 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | (1 | ) | $ | (a) | $ | (1 | ) | ||||||||||
(a) | Not applicable. | |||||||||||||||||
(b) | Ameren amounts include the elimination of financial power contracts between Ameren Illinois and Marketing Company. | |||||||||||||||||
(c) | The change in unrealized losses was due to decreases in long-term power prices applied to 20-year Ameren Illinois’ swap contracts, which expire May 2032. | |||||||||||||||||
Transfers in or out of Level 3 represent either (1) existing assets and liabilities that were previously categorized as a higher level but were recategorized to Level 3 because the inputs to the model became unobservable during the period, or (2) existing assets and liabilities that were previously classified as Level 3 but were recategorized to a higher level because the lowest significant input became observable during the period. Transfers out of Level 3 into Level 2 for natural gas derivatives were due to management previously using broker quotations to estimate the fair value of natural gas contracts and changing to estimates based upon exchange closing prices without significant unobservable adjustments in the first quarter of 2012. Estimates of fair value based on exchange closing prices are deemed to be a more accurate approximation of natural gas prices. Transfers between Level 2 and Level 3 for power derivatives and between Level 1 and Level 3 for fuel oils were primarily caused by changes in availability of financial trades observable on electronic exchanges between the periods shown below. Any reclassifications are reported as transfers out of Level 3 at the fair value measurement reported at the beginning of the period in which the changes occur. For the three and nine months ended September 30, 2013, and 2012, there were no transfers between Level 1 and Level 2 related to derivative commodity contracts. The following table summarizes all transfers between fair value hierarchy levels related to derivative commodity contracts for the three and nine months ended September 30, 2013, and 2012: | ||||||||||||||||||
Three Months | Nine Months | |||||||||||||||||
2013 | 2012 | 2013 | 2012 | |||||||||||||||
Ameren - derivative commodity contracts: | ||||||||||||||||||
Transfers into Level 3 / Transfers out of Level 1 - Fuel oils | $ | — | $ | — | $ | — | $ | 2 | ||||||||||
Transfers out of Level 3 / Transfers into Level 2 - Natural gas | — | — | — | 185 | ||||||||||||||
Transfers into Level 3 / Transfers out of Level 2 - Power | (1 | ) | — | (3 | ) | — | ||||||||||||
Transfers out of Level 3 / Transfers into Level 2 - Power | — | (2 | ) | 4 | (4 | ) | ||||||||||||
Net fair value of Level 3 transfers | $ | (1 | ) | $ | (2 | ) | $ | 1 | $ | 183 | ||||||||
Ameren Missouri - derivative commodity contracts: | ||||||||||||||||||
Transfers into Level 3 / Transfers out of Level 1 - Fuel oils | $ | — | $ | — | $ | — | $ | 2 | ||||||||||
Transfers out of Level 3 / Transfers into Level 2 - Natural gas | — | — | — | 15 | ||||||||||||||
Transfers into Level 3 / Transfers out of Level 2 - Power | (1 | ) | — | (3 | ) | — | ||||||||||||
Transfers out of Level 3 / Transfers into Level 2 - Power | — | (2 | ) | 4 | (4 | ) | ||||||||||||
Net fair value of Level 3 transfers | $ | (1 | ) | $ | (2 | ) | $ | 1 | $ | 13 | ||||||||
Ameren Illinois - derivative commodity contracts: | ||||||||||||||||||
Transfers out of Level 3 / Transfers into Level 2 - Natural gas | $ | — | $ | — | $ | — | $ | 170 | ||||||||||
The Ameren Companies’ carrying amounts of cash and cash equivalents approximate fair value because of the short-term nature of these instruments and are considered to be Level 1 in the fair value hierarchy. Ameren’s and Ameren Missouri’s carrying amounts of investments in debt securities related to the two CTs from the city of Bowling Green and Audrain County approximate fair value. These investments are classified as held-to-maturity. These investments are considered Level 2 in the fair value hierarchy as they are valued based on similar market transactions. The Ameren Companies’ short-term borrowings also approximate fair value because of their short-term nature. Short-term borrowings are considered to be Level 2 in the fair value hierarchy as they are valued based on market rates for similar market transactions. The estimated fair value of long-term debt and preferred stock is based on the quoted market prices for same or similar issuances for companies with similar credit profiles or on the current rates offered to the Ameren Companies for similar financial instruments, which fair value measurement is considered Level 2 in the fair value hierarchy. | ||||||||||||||||||
The following table presents the carrying amounts and estimated fair values of our long-term debt and capital lease obligations and preferred stock at September 30, 2013, and December 31, 2012: | ||||||||||||||||||
30-Sep-13 | 31-Dec-12 | |||||||||||||||||
Carrying | Fair | Carrying | Fair | |||||||||||||||
Amount | Value | Amount | Value | |||||||||||||||
Ameren:(a)(b) | ||||||||||||||||||
Long-term debt and capital lease obligations (including current portion) | $ | 6,158 | $ | 6,596 | $ | 6,157 | $ | 7,110 | ||||||||||
Preferred stock | 142 | 123 | 142 | 123 | ||||||||||||||
Ameren Missouri: | ||||||||||||||||||
Long-term debt and capital lease obligations (including current portion) | $ | 4,006 | $ | 4,227 | $ | 4,006 | $ | 4,625 | ||||||||||
Preferred stock | 80 | 74 | 80 | 74 | ||||||||||||||
Ameren Illinois: | ||||||||||||||||||
Long-term debt (including current portion) | $ | 1,727 | $ | 1,922 | $ | 1,727 | $ | 2,020 | ||||||||||
Preferred stock | 62 | 49 | 62 | 49 | ||||||||||||||
(a) | Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations. | |||||||||||||||||
(b) | Preferred stock along with the noncontrolling interest of EEI is recorded in “Noncontrolling Interests” on the balance sheet. |
Related_Party_Transactions
Related Party Transactions | 9 Months Ended | ||||||||||||||
Sep. 30, 2013 | |||||||||||||||
Text Block [Abstract] | ' | ||||||||||||||
RELATED PARTY TRANSACTIONS | ' | ||||||||||||||
RELATED PARTY TRANSACTIONS | |||||||||||||||
Ameren and its subsidiaries have engaged in, and may in the future engage in, affiliate transactions in the normal course of business. These transactions primarily consist of natural gas and power purchases and sales, asset transactions, guarantees, services received or rendered, and borrowings and lendings. | |||||||||||||||
Transactions between affiliates are reported as intercompany transactions on their financial statements, but are eliminated in consolidation for Ameren’s financial statements. For a discussion of our material related party agreements, see Note 14 - Related Party Transactions under Part II, Item 8, of the Form 10-K. | |||||||||||||||
Collateral Postings | |||||||||||||||
Under the terms of the Illinois power procurement agreements entered into through a RFP process administered by the IPA, suppliers must post collateral under certain market conditions to protect Ameren Illinois in the event of nonperformance. The collateral postings are unilateral, meaning that only the suppliers would be required to post collateral. Therefore, Ameren Missouri and Marketing Company, as winning suppliers in the RFP process, may be required to post collateral. As of December 31, 2012, and September 30, 2013, there were no collateral postings required of Ameren Missouri or Marketing Company related to the Illinois power procurement agreements. | |||||||||||||||
Marketing Company Sale of Trade Receivables to Ameren Illinois | |||||||||||||||
In accordance with the Illinois Public Utilities Act, beginning in June 2012, Ameren Illinois is required to purchase alternative retail electric suppliers’ receivables relating to Ameren Illinois’ delivery service customers who elected to receive power supply from the alternative retail electric supplier. Marketing Company sells and Ameren Illinois purchases trade receivables relating to the power supply of residential customers using Marketing Company as their alternative retail electric supplier. Marketing Company has no continuing involvement with or control over the trade receivables after the sale is completed to Ameren Illinois, and neither company has any restrictions on the assets associated with these purchase and sale transactions. As of September 30, 2013, Ameren Illinois’ payable to Marketing Company for the purchase of trade receivables totaled $17 million. During the nine months ended September 30, 2013, Ameren Illinois purchased $115 million of trade receivables from Marketing Company at a discount of $2 million. Marketing Company’s receivable from Ameren Illinois as well as Ameren Illinois’ payable to Marketing Company are eliminated in Ameren’s consolidated financial statements. After the New AER divestiture is complete, these transactions will no longer be eliminated in Ameren’s consolidated financial statements. | |||||||||||||||
Parent Company Guarantees | |||||||||||||||
In the ordinary course of business, Ameren (parent) enters into various agreements providing financial assurance to third parties on behalf of its subsidiaries. Such agreements include, for example, guarantees and letters of credit. These agreements are entered into primarily to support or enhance the creditworthiness otherwise attributed to a subsidiary on a stand-alone basis, thereby facilitating the extension of sufficient credit and reducing the amount of cash collateral required to be posted. These agreements guarantee performance by Ameren's subsidiaries of obligations already reflected on Ameren's consolidated balance sheet. | |||||||||||||||
Upon the divestiture of New AER, the transaction agreement with IPH requires Ameren (parent) to maintain its financial obligations with respect to all credit support provided to New AER as of the closing date of such divestiture and provide such additional credit support as required by contracts entered into prior to the closing date, in each case for up to 24 months after the closing. IPH shall indemnify Ameren for any payments Ameren makes pursuant to these credit support obligations if the counterparty does not return the posted collateral to Ameren. IPH's indemnification obligation will be secured by certain AERG and Genco assets. In addition, Dynegy has provided a limited guarantee of $25 million to Ameren (parent) pursuant to which Dynegy will, among other things, guarantee IPH's indemnification obligations for a period of up to 24 months after the closing. See Note 2 - Divestiture Transactions and Discontinued Operations. | |||||||||||||||
At September 30, 2013, Ameren had a total of $192 million in guarantees outstanding, excluding a guarantee for Medina Valley related to the amended put option agreement. This guarantee expired in October 2013 with the closing of Genco’s sale of the Elgin, Gibson City, and Grand Tower gas-fired energy centers to Medina Valley. See Note 2 - Divestiture Transactions and Discontinued Operations for further discussion of the put option agreement. See below for further discussion of the outstanding guarantees: | |||||||||||||||
• | $154 million related to Ameren's Merchant Generation segment, primarily for Marketing Company as support for physically and financially settled power transactions with its counterparties. As of September 30, 2013, this amount does not represent an incremental consolidated Ameren obligation; rather, it represents Ameren parental guarantees of subsidiary obligations to third parties, which may include affiliates, in order to allow the subsidiaries the flexibility needed to conduct business with counterparties without having to post other forms of collateral. Ameren's estimated exposure for obligations under transactions covered by these guarantees was $25 million at September 30, 2013, which represents the total amount Ameren (parent) could be required to fund based on September 30, 2013 market prices. | ||||||||||||||
• | $25 million provided to a clearing broker acting as futures commission merchant for the clearing of certain power, natural gas, and fuels commodity transactions for AER. | ||||||||||||||
• | $13 million related to requirements for asset transactions, leasing, Medina Valley transactions through MISO and other agreements. At September 30, 2013, Ameren estimated it had no exposure to any of these guarantees. | ||||||||||||||
Additionally, at September 30, 2013, Ameren had issued letters of credit totaling $14 million as credit support to certain subsidiaries. | |||||||||||||||
Miscellaneous Support Services | |||||||||||||||
Ameren Missouri and Ameren Illinois provide storm-related and miscellaneous support services to each other on an as- needed basis. Ameren Illinois provided to Ameren Missouri $2 million in storm-related support services during the nine months ended September 30, 2013. Ameren Missouri provided to Ameren Illinois $1 million in miscellaneous support services during the three and nine months ended September 30, 2013. Ameren Missouri provided to Ameren Illinois $1 million in miscellaneous support services during the nine months ended September 30, 2012. These amounts are reflected in “Operating Revenues - Other” on the statement of income and comprehensive income. | |||||||||||||||
Money Pools | |||||||||||||||
See Note 4 - Short-term Debt and Liquidity for a discussion of affiliate borrowing arrangements. | |||||||||||||||
The following table presents the impact on Ameren Missouri and Ameren Illinois of related party transactions for the three and nine months ended September 30, 2013, and 2012. It is based primarily on the agreements discussed above and in Note 14 - Related Party Transactions under Part II, Item 8, of the Form 10-K, and the money pool arrangements discussed in Note 4 - Short-term Debt and Liquidity of this report. | |||||||||||||||
Three Months | Nine Months | ||||||||||||||
Agreement | Income Statement | Ameren | Ameren | Ameren | Ameren | ||||||||||
Line Item | Missouri | Illinois | Missouri | Illinois | |||||||||||
Ameren Missouri power supply | Operating Revenues | 2013 | $ | (b) | $ | (a) | $ | 1 | $ | (a) | |||||
agreements with Ameren Illinois | 2012 | (b) | (a) | (b) | (a) | ||||||||||
Ameren Missouri and Ameren Illinois | Operating Revenues | 2013 | 4 | (b) | 15 | 1 | |||||||||
rent and facility services | 2012 | 5 | (b) | 14 | 1 | ||||||||||
Ameren Missouri and Genco gas | Operating Revenues | 2013 | (b) | (a) | 1 | (a) | |||||||||
transportation agreement | 2012 | (b) | (a) | 1 | (a) | ||||||||||
Transmission services agreement | Operating Revenues | 2013 | (a) | 11 | (a) | 24 | |||||||||
with Marketing Company | 2012 | (a) | 5 | (a) | 11 | ||||||||||
Total Operating Revenues | 2013 | $ | 4 | $ | 11 | $ | 17 | $ | 25 | ||||||
2012 | 5 | 5 | 15 | 12 | |||||||||||
Ameren Illinois power supply | Purchased Power | 2013 | $ | (a) | $ | 46 | $ | (a) | $ | 94 | |||||
agreements with Marketing Company | 2012 | (a) | 83 | (a) | 243 | ||||||||||
Ameren Illinois power supply | Purchased Power | 2013 | (a) | (b) | (a) | 1 | |||||||||
agreements with Ameren Missouri | 2012 | (a) | (b) | (a) | (b) | ||||||||||
Total Purchased Power | 2013 | $ | (a) | $ | 46 | $ | (a) | $ | 95 | ||||||
2012 | (a) | 83 | (a) | 243 | |||||||||||
Ameren Services support services | Other Operations and Maintenance | 2013 | $ | 25 | $ | 22 | $ | 85 | $ | 70 | |||||
agreement | 2012 | 26 | 22 | 81 | 67 | ||||||||||
Insurance premiums(c) | Other Operations and Maintenance | 2013 | (b) | (a) | (b) | (a) | |||||||||
2012 | (b) | (a) | (b) | (a) | |||||||||||
Total Other Operations and | 2013 | $ | 25 | $ | 22 | $ | 85 | $ | 70 | ||||||
Maintenance Expenses | 2012 | 26 | 22 | 81 | 67 | ||||||||||
Money pool borrowings (advances) | Interest Charges | 2013 | $ | (b) | $ | (b) | $ | $1 | $ | (b) | |||||
2012 | (b) | (b) | (b) | (b) | |||||||||||
(a) | Not applicable. | ||||||||||||||
(b) | Amount less than $1 million. | ||||||||||||||
(c) | Represents insurance premiums paid to Missouri Energy Risk Assurance Company, an affiliate, for replacement power. |
Commitments_And_Contingencies
Commitments And Contingencies | 9 Months Ended | |||||||||||||||||||||||||||
Sep. 30, 2013 | ||||||||||||||||||||||||||||
Commitments and Contingencies Disclosure [Abstract] | ' | |||||||||||||||||||||||||||
COMMITMENTS AND CONTINGENCIES | ' | |||||||||||||||||||||||||||
COMMITMENTS AND CONTINGENCIES | ||||||||||||||||||||||||||||
We are involved in legal, tax and regulatory proceedings before various courts, regulatory commissions, and governmental agencies with respect to matters that arise in the ordinary course of business, some of which involve substantial amounts of money. We believe that the final disposition of these proceedings, except as otherwise disclosed in the notes to our financial statements in this report and in our Form 10-K, will not have a material adverse effect on our results of operations, financial position, or liquidity. | ||||||||||||||||||||||||||||
Reference is made to Note 1 - Summary of Significant Accounting Policies, Note 2 - Rate and Regulatory Matters, Note 14 - Related Party Transactions, and Note 15 - Commitments and Contingencies under Part II, Item 8, of the Form 10-K. See also Note 1 - Summary of Significant Accounting Policies, Note 2 - Divestiture Transactions and Discontinued Operations, Note 3 - Rate and Regulatory Matters, Note 9 - Related Party Transactions and Note 11 - Callaway Energy Center in this report. | ||||||||||||||||||||||||||||
Callaway Energy Center | ||||||||||||||||||||||||||||
The following table presents insurance coverage at Ameren Missouri’s Callaway energy center at September 30, 2013. The property coverage and the nuclear liability coverage must be renewed on April 1 and January 1, respectively, of each year. | ||||||||||||||||||||||||||||
Type and Source of Coverage | Maximum Coverages | Maximum Assessments | ||||||||||||||||||||||||||
for Single Incidents | ||||||||||||||||||||||||||||
Public liability and nuclear worker liability: | ||||||||||||||||||||||||||||
American Nuclear Insurers | $ | 375 | $ | — | ||||||||||||||||||||||||
Pool participation | 13,312 | (a) | 128 | (b) | ||||||||||||||||||||||||
$ | 13,687 | (c) | $ | 128 | ||||||||||||||||||||||||
Property damage: | ||||||||||||||||||||||||||||
Nuclear Electric Insurance Ltd. | $ | 2,250 | (d) | $ | 23 | (e) | ||||||||||||||||||||||
European Mutual Association for Nuclear Insurance | 500 | (f) | — | |||||||||||||||||||||||||
$ | 2,750 | $ | 23 | |||||||||||||||||||||||||
Replacement power: | ||||||||||||||||||||||||||||
Nuclear Electric Insurance Ltd. | $ | 490 | (g) | $ | 9 | (e) | ||||||||||||||||||||||
Missouri Energy Risk Assurance Company | 64 | (h) | — | |||||||||||||||||||||||||
(a) | Provided through mandatory participation in an industry-wide retrospective premium assessment program. | |||||||||||||||||||||||||||
(b) | Retrospective premium under Price-Anderson. This is subject to retrospective assessment with respect to a covered loss in excess of $375 million in the event of an incident at any licensed United States commercial reactor, payable at $19 million per year. | |||||||||||||||||||||||||||
(c) | Limit of liability for each incident under the Price-Anderson liability provisions of the Atomic Energy Act of 1954, as amended. A company could be assessed up to $128 million per incident for each licensed reactor it operates with a maximum of $19 million per incident to be paid in a calendar year for each reactor. This limit is subject to change to account for the effects of inflation and changes in the number of licensed reactors. | |||||||||||||||||||||||||||
(d) | Nuclear Electric Insurance Ltd. provides $2.25 billion in property damage, decontamination, and premature decommissioning insurance. There is a $1.7 billion sublimit for non-radiation events of which the top $200 million is a shared limit with other generators purchasing this coverage and includes one free reinstatement. | |||||||||||||||||||||||||||
(e) | All Nuclear Electric Insurance Ltd. insured plants could be subject to assessments should losses exceed the accumulated funds from Nuclear Electric Insurance Ltd. | |||||||||||||||||||||||||||
(f) | European Mutual Association for Nuclear Insurance provides $500 million in excess of the $2.25 billion property coverage and $1.7 billion non-radiation coverage. | |||||||||||||||||||||||||||
(g) | Provides replacement power cost insurance in the event of a prolonged accidental outage at our nuclear energy center. Weekly indemnity up to $4.5 million for 52 weeks, which commences after the first eight weeks of an outage, plus up to $3.6 million per week for a minimum of 71 weeks thereafter for a total not exceeding the policy limit of $490 million. Effective April 1, 2013, non-radiation events are sub-limited to $327.6 million. | |||||||||||||||||||||||||||
(h) | Provides replacement power cost insurance in the event of a prolonged accidental outage at our nuclear energy center. The coverage commences after the first 52 weeks of insurance coverage from Nuclear Electric Insurance Ltd. and is for a weekly indemnity up to $900,000 for 71 weeks in excess of the $3.6 million per week set forth above. Missouri Energy Risk Assurance Company LLC is an affiliate and has reinsured this coverage with third-party insurance companies. See Note 9 - Related Party Transactions for more information on this affiliate transaction. | |||||||||||||||||||||||||||
The Price-Anderson Act is a federal law that limits the liability for claims from an incident involving any licensed United States commercial nuclear power facility. The limit is based on the number of licensed reactors. The limit of liability and the maximum potential annual payments are adjusted at least every five years for inflation to reflect changes in the Consumer Price Index. The five-year inflationary adjustment was effective September 10, 2013. Owners of a nuclear reactor cover this exposure through a combination of private insurance and mandatory participation in a financial protection pool, as established by Price-Anderson. | ||||||||||||||||||||||||||||
Losses resulting from terrorist attacks are covered under Nuclear Electric Insurance Ltd.’s policies, subject to an industry-wide aggregate policy limit of $3.24 billion within a 12-month period for coverage for such terrorist acts. | ||||||||||||||||||||||||||||
If losses from a nuclear incident at the Callaway energy center exceed the limits of, or are not covered by insurance, or if coverage is unavailable, Ameren Missouri is at risk for any uninsured losses. If a serious nuclear incident were to occur, it could have a material adverse effect on Ameren’s and Ameren Missouri’s results of operations, financial position, or liquidity. | ||||||||||||||||||||||||||||
Other Obligations | ||||||||||||||||||||||||||||
To supply a portion of the fuel requirements of our energy centers, we have entered into various long-term commitments for the procurement of coal, natural gas, nuclear fuel, and methane gas. We also have entered into various long-term commitments for purchased power and natural gas for distribution. The table below presents our estimated fuel, purchased power, and other commitments at September 30, 2013. Ameren’s and Ameren Missouri’s purchased power obligations include a 102-megawatt power purchase agreement with a wind farm operator that expires in 2024. Ameren’s and Ameren Illinois’ purchased power obligations include the Ameren Illinois power purchase agreements entered into as part of the IPA-administered power procurement process. Included in the Other column are minimum purchase commitments under contracts for equipment, design and construction, and meter reading services at September 30, 2013. Ameren's and Ameren Illinois' Other column also include obligations related to IEIMA. In addition, the Other column includes Ameren's and Ameren Missouri's obligations related to energy efficiency programs under the MEEIA as approved by the MoPSC's December 2012 electric rate order. The order provides that, beginning in 2013, Ameren Missouri will invest approximately $147 million over three years for energy efficiency programs. | ||||||||||||||||||||||||||||
Coal | Natural | Nuclear | Purchased | Methane | Other | Total | ||||||||||||||||||||||
Gas | Fuel | Power(a) | Gas | |||||||||||||||||||||||||
Ameren:(b) | ||||||||||||||||||||||||||||
2013 | $ | 605 | $ | 109 | $ | 17 | $ | 162 | $ | 1 | $ | 87 | $ | 981 | ||||||||||||||
2014 | 617 | 292 | 68 | 302 | 3 | 158 | 1,440 | |||||||||||||||||||||
2015 | 640 | 155 | 63 | 154 | 4 | 114 | 1,130 | |||||||||||||||||||||
2016 | 665 | 85 | 81 | 67 | 4 | 64 | 966 | |||||||||||||||||||||
2017 | 683 | 47 | 58 | 44 | 5 | 56 | 893 | |||||||||||||||||||||
Thereafter | 245 | 100 | 216 | 501 | 97 | 246 | 1,405 | |||||||||||||||||||||
Total | $ | 3,455 | $ | 788 | $ | 503 | $ | 1,230 | $ | 114 | $ | 725 | $ | 6,815 | ||||||||||||||
Ameren Missouri: | ||||||||||||||||||||||||||||
2013 | $ | 605 | $ | 27 | $ | 17 | $ | 3 | $ | 1 | $ | 66 | $ | 719 | ||||||||||||||
2014 | 617 | 50 | 68 | 19 | 3 | 127 | 884 | |||||||||||||||||||||
2015 | 640 | 30 | 63 | 19 | 4 | 85 | 841 | |||||||||||||||||||||
2016 | 665 | 16 | 81 | 19 | 4 | 40 | 825 | |||||||||||||||||||||
2017 | 683 | 11 | 58 | 19 | 5 | 32 | 808 | |||||||||||||||||||||
Thereafter | 245 | 28 | 216 | 129 | 97 | 144 | 859 | |||||||||||||||||||||
Total | $ | 3,455 | $ | 162 | $ | 503 | $ | 208 | $ | 114 | $ | 494 | $ | 4,936 | ||||||||||||||
Ameren Illinois: | ||||||||||||||||||||||||||||
2013 | $ | — | $ | 82 | $ | — | $ | 159 | $ | — | $ | 9 | $ | 250 | ||||||||||||||
2014 | — | 242 | — | 283 | — | 22 | 547 | |||||||||||||||||||||
2015 | — | 125 | — | 135 | — | 24 | 284 | |||||||||||||||||||||
2016 | — | 69 | — | 48 | — | 24 | 141 | |||||||||||||||||||||
2017 | — | 36 | — | 25 | — | 24 | 85 | |||||||||||||||||||||
Thereafter | — | 72 | — | 372 | — | 102 | 546 | |||||||||||||||||||||
Total | $ | — | $ | 626 | $ | — | $ | 1,022 | $ | — | $ | 205 | $ | 1,853 | ||||||||||||||
(a) | The purchased power amounts for Ameren and Ameren Illinois includes twenty-year agreements for renewable energy credits that were entered into in December 2010 with various renewable energy suppliers. The agreements contain a provision that allows Ameren Illinois to reduce the quantity purchased in the event that Ameren Illinois would not be able to recover the costs associated with the renewable energy credits. | |||||||||||||||||||||||||||
(b) | Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations. | |||||||||||||||||||||||||||
Ameren Illinois has entered into an agreement, through a process administered by the IPA, to purchase power from a repowered unit at the Meredosia energy center designed for permanent carbon dioxide capture and storage, annually over a 20-year period beginning in 2017 for its electric delivery service customers. The agreement is contingent on the parties interested in repowering the unit at the currently idle Meredosia energy center reaching certain milestones related to the construction and commencement of operations of this unit. Construction has not begun on the unit at this energy center; therefore, Ameren Illinois’ obligations are not yet certain at this time and consequently not included in the table above. If the plant is not in service by 2019, Ameren Illinois can terminate the agreement. | ||||||||||||||||||||||||||||
Environmental Matters | ||||||||||||||||||||||||||||
We are subject to various environmental laws and regulations enforced by federal, state, and local authorities. From the beginning phases of siting and development to the ongoing operation of existing or new electric generation, transmission and distribution facilities and natural gas storage, transmission and distribution facilities, our activities involve compliance with diverse environmental laws and regulations. These laws and regulations address emissions, impacts to air, land, and water, noise, protected natural and cultural resources (such as wetlands, endangered species and other protected wildlife, and archeological and historical resources), and chemical and waste handling. Complex and lengthy processes are required to obtain and renew approvals, permits, or licenses for new, existing or modified facilities. Additionally, the use and handling of various chemicals or hazardous materials (including wastes) require release prevention plans and emergency response procedures. | ||||||||||||||||||||||||||||
In addition to existing environmental laws and regulations, including the Illinois MPS that applies to AER's coal-fired energy centers in Illinois, the EPA is developing regulations that will have a significant impact on the electric utility industry. These regulations could be particularly burdensome for certain companies, including Ameren, Ameren Missouri, and AER, that operate coal-fired energy centers. Significant new rules proposed or promulgated since the beginning of 2010 include the regulation of greenhouse gas emissions from new energy centers; revised national ambient air quality standards for fine particulates, SO2, and NOx emissions; the CSAPR, which would have required further reductions of SO2 emissions and NOx emissions from energy centers; a regulation governing management of CCR and coal ash impoundments; the MATS, which require reduction of emissions of mercury, toxic metals, and acid gases from energy centers; revised NSPS for particulate matter, SO2, and NOx emissions from new sources; new effluent standards applicable to discharges from steam-electric generating units; and new regulations under the Clean Water Act that could require significant capital expenditures such as new water intake structures or cooling towers at our energy centers. The EPA is expected to propose CO2 limits for existing fossil fuel-fired electric generation units in the future. These new and proposed regulations, if adopted, may be challenged through litigation, so their ultimate implementation as well as the timing of any such implementation is uncertain, as evidenced by the CSAPR being vacated and remanded back to the EPA by the United States Court of Appeals for the District of Columbia Circuit in August 2012. Although many details of these future regulations are unknown, the combined effects of the new and proposed environmental regulations may result in significant capital expenditures and increased operating costs over the next five to ten years for Ameren, Ameren Missouri and AER. Compliance with these environmental laws and regulations could be prohibitively expensive. If they are, these regulations could require us to close or to significantly alter the operation of our energy centers, which could have an adverse effect on our results of operations, financial position, and liquidity, including the impairment of long-lived assets. Failure to comply with environmental laws and regulations might also result in the imposition of fines, penalties, and injunctive measures. | ||||||||||||||||||||||||||||
The estimates in the tables below contain all of the known capital costs to comply with existing environmental regulations, including the CAIR, and our assessment of the potential impacts of the MATS and of the EPA's proposed regulation for CCR as of September 30, 2013. In addition, the estimates assume that CCR will continue to be regarded as nonhazardous. The estimates do not include the impacts of regulations proposed by the EPA under the Clean Water Act in March 2011 regarding cooling water intake structures or the impact of the effluent standards applicable to steam-electric generating units that the EPA proposed in April 2013, as the technology requirements ultimately to be selected in these final rules are not yet known. The estimates shown in the tables below could change significantly depending upon a variety of factors including: | ||||||||||||||||||||||||||||
• | Ameren’s divestiture of its Merchant Generation business; | |||||||||||||||||||||||||||
• | additional or modified federal or state requirements; | |||||||||||||||||||||||||||
• | further regulation of greenhouse gas emissions; | |||||||||||||||||||||||||||
• | revisions to CAIR or reinstatement of CSAPR; | |||||||||||||||||||||||||||
• | delays or accelerations of rulemaking and implementation by the EPA or state agencies; | |||||||||||||||||||||||||||
• | new national ambient air quality standards, new standards intended to achieve national ambient air quality standards, or changes to existing standards for ozone, fine particulates, SO2, and NOx emissions; | |||||||||||||||||||||||||||
• | additional or new rules governing air pollutant transport; | |||||||||||||||||||||||||||
• | regulations or requirements under the Clean Water Act regarding cooling water intake structures or effluent standards; | |||||||||||||||||||||||||||
• | finalized regulations classifying CCR as being hazardous or imposing additional requirements on the management of CCR; | |||||||||||||||||||||||||||
• | new limitations or standards under the Clean Water Act applicable to discharges from steam-electric generating units; | |||||||||||||||||||||||||||
• | new technology; | |||||||||||||||||||||||||||
• | changes in expected power prices; | |||||||||||||||||||||||||||
• | variations in costs of material or labor; and | |||||||||||||||||||||||||||
• | alternative compliance strategies or investment decisions. | |||||||||||||||||||||||||||
Continuing Operations: | ||||||||||||||||||||||||||||
2013 | 2014 - 2017 | 2018 - 2022 | Total | |||||||||||||||||||||||||
AMO(a) | $ | 105 | $ | 215 | - | $ | 260 | $ | 795 | - | $ | 975 | $ | 1,115 | - | $ | 1,340 | |||||||||||
(a) | Ameren Missouri’s expenditures are expected to be recoverable from ratepayers. | |||||||||||||||||||||||||||
Discontinued Operations: | ||||||||||||||||||||||||||||
2013 | 2014 - 2017 | 2018 - 2022 | Total | |||||||||||||||||||||||||
Genco(a) | $ | 30 | $ | 100 | - | $ | 125 | $ | 220 | - | $ | 270 | $ | 350 | - | $ | 425 | |||||||||||
AERG | 5 | 20 | - | 25 | 20 | - | 25 | 45 | - | 55 | ||||||||||||||||||
Total(b) | $ | 35 | $ | 120 | - | $ | 150 | $ | 240 | - | $ | 295 | $ | 395 | - | $ | 480 | |||||||||||
(a) | Includes estimated costs of approximately $20 million annually, excluding capitalized interest, from 2013 through 2017 for construction of two scrubbers at the Newton energy center. | |||||||||||||||||||||||||||
(b) | Assumes the Merchant Generation facilities are owned by Ameren. | |||||||||||||||||||||||||||
The following sections describe the more significant environmental laws and rules that affect or could affect our operations. | ||||||||||||||||||||||||||||
Clean Air Act | ||||||||||||||||||||||||||||
Both federal and state laws require significant reductions in SO2 and NOx emissions that result from burning fossil fuels. In March 2005, the EPA issued regulations with respect to SO2 and NOx emissions (the CAIR). The CAIR requires generating facilities in 28 states, including Missouri and Illinois, and the District of Columbia, to participate in cap-and-trade programs to reduce annual SO2 emissions, annual NOx emissions, and ozone season NOx emissions. | ||||||||||||||||||||||||||||
In December 2008, the United States Court of Appeals for the District of Columbia Circuit remanded the CAIR to the EPA for further action to remedy the rule's flaws, but allowed the CAIR's cap-and-trade programs to remain effective until they are replaced by the EPA. In July 2011, the EPA issued the CSAPR as the CAIR replacement. On December 30, 2011, the United States Court of Appeals for the District of Columbia Circuit issued a stay of the CSAPR. In August 2012, the United States Court of Appeals for the District of Columbia Circuit issued a ruling that vacated the CSAPR in its entirety, finding that the EPA exceeded its authority in imposing the CSAPR's emission limits on states. In March 2013, the EPA and certain environmental groups filed an appeal of the Court of Appeals’ remand of CSAPR to the United States Supreme Court. The United States Supreme Court has agreed to consider the appeal and is expected to issue a ruling on the appeal during its current term, which ends in June 2014. The EPA will continue to administer the CAIR until a new rule is ultimately adopted or the United States Supreme Court overturns the decision to vacate the CSAPR. | ||||||||||||||||||||||||||||
In December 2011, the EPA issued the MATS under the Clean Air Act, which require emission reductions for mercury and other hazardous air pollutants, such as acid gases, toxic metals, and particulate matter by setting emission limits equal to the average emissions of the best performing 12% of existing coal and oil-fired electric generating units. Also, the standards require reductions in hydrogen chloride emissions, which were not regulated previously, and for the first time require continuous monitoring systems for hydrogen chloride, mercury, and particulate matter. The MATS do not require a specific control technology to achieve the emission reductions. The MATS will apply to each unit at a coal-fired power plant; however in certain cases, emission compliance can be achieved by averaging emissions from similar electric generating units at the same power plant. Compliance is required by April 2015 or, with a case-by-case extension, by April 2016. Ameren Missouri's Labadie and Meramec energy centers requested and were granted extensions to April 2016 to comply with the MATS. | ||||||||||||||||||||||||||||
Separately, in December 2012, the EPA issued a final rule that made the national ambient air quality standard for fine particulate matter more stringent. States must develop control measures designed to reduce the emission of fine particulate matter below required levels to achieve compliance with the new standard. Such measures may or may not apply to energy centers but could require reductions in SO2 and NOx emissions. States are required to demonstrate compliance with the rule by 2020, or 2025 if an extension of time to achieve compliance is granted. Ameren Missouri and AER are currently evaluating the new standard while the states of Missouri and Illinois develop their attainment plans. | ||||||||||||||||||||||||||||
In September 2011, the EPA announced that it was implementing the 2008 national ambient air quality standards for ozone. The EPA is required to revisit these standards for ozone again in 2013. The states of Illinois and Missouri will be required to develop attainment plans to comply with the 2008 ambient air quality standards for ozone, which could result in additional emission control requirements for power plants by 2020. Ameren, Ameren Missouri and AER continue to assess the impacts of these new standards. | ||||||||||||||||||||||||||||
In July 2013, the EPA issued a final rule designating portions of the United States, including parts of Illinois and Missouri, as nonattainment for the national ambient air quality standard for SO2. The designations became effective in October 2013, and the states must develop plans in the next 18 months to reduce emissions so that they can achieve the ambient air quality standards within five years. Ameren, Ameren Missouri and AER are assessing the impact of this designation. | ||||||||||||||||||||||||||||
Ameren Missouri's current environmental compliance plan for air emissions from its energy centers includes burning ultra-low-sulfur coal and installing new or optimizing existing pollution control equipment. In July 2011, Ameren Missouri contracted to procure significantly greater volumes of lower-sulfur-content coal than Ameren Missouri's energy centers had historically burned, which allowed Ameren Missouri to eliminate or postpone capital expenditures for pollution control equipment. In 2010, Ameren Missouri completed the installation of two scrubbers at its Sioux energy center to reduce SO2 emissions. Currently, Ameren Missouri's compliance plan assumes the installation of two scrubbers, mercury control technology, and precipitator upgrades at multiple energy centers within its coal-fired fleet during the next 10 years. However, Ameren Missouri is currently evaluating its operations and options to determine how to comply with the MATS and other recently finalized or proposed EPA regulations. | ||||||||||||||||||||||||||||
In September 2012, the Illinois Pollution Control Board granted AER a variance to extend compliance dates for SO2 emission levels contained in the MPS through December 31, 2019, subject to certain conditions described below. The Illinois Pollution Control Board approved AER's proposed plan to restrict its SO2 emissions through 2014 to levels lower than those previously required by the MPS to offset any environmental impact from the variance. The Illinois Pollution Control Board's order also included the following provisions: | ||||||||||||||||||||||||||||
• | A schedule of milestones for completion of various aspects of the installation and completion of the scrubber projects at Genco's Newton energy center; the first milestone relates to the completion of engineering design by July 2015 while the last milestone relates to major equipment components being placed into final position on or before September 1, 2019. | |||||||||||||||||||||||||||
• | A requirement for AER to refrain from operating the Meredosia and Hutsonville energy centers through December 31, 2020; however, this restriction does not impact Genco's ability, or Ameren’s ability after the divestiture of New AER occurs, to make the Meredosia energy center available for any parties that may be interested in repowering one of its units to create an oxy-fuel combustion coal-fired energy center designed for permanent carbon dioxide capture and storage. | |||||||||||||||||||||||||||
See Note 2 - Divestiture Transactions and Discontinued Operations for additional information regarding Ameren’s divestiture of New AER and a request filed with the Illinois Pollution Control Board for a variance in favor of IPH on the same material terms as the Illinois MPS variance granted to AER in September 2012. | ||||||||||||||||||||||||||||
Under the MPS, AER is required to reduce mercury, NOx and SO2 emissions with declining limits that started in 2009 for mercury and in 2010 for NOx and SO2. The final NOx limit became effective in 2012. The final mercury limit will become effective in 2015 and the final SO2 limit will become effective by the end of 2019. The Illinois Pollution Control Board's September 2012 variance gives AER additional time for economic recovery and related power price improvements necessary to support scrubber installations and other pollution controls at some of AER's energy centers. To comply with the MPS and other air emissions laws and regulations, AER is installing equipment designed to reduce its emissions of mercury, NOx, and SO2. AER has installed three scrubbers at two energy centers. Two additional scrubbers are being constructed at the Newton energy center. AER will continue to review and adjust its compliance plans in light of evolving outlooks for power and capacity prices, delivered fuel costs, emission standards required under environmental laws and regulations, and compliance technologies, among other factors. | ||||||||||||||||||||||||||||
Environmental compliance costs could be prohibitive at some of Ameren's, Ameren Missouri's and AER's energy centers as the expected return from these investments, at current market prices for energy and capacity, might not justify the required capital expenditures or their continued operation, which could result in the impairment of long-lived assets. | ||||||||||||||||||||||||||||
Emission Allowances | ||||||||||||||||||||||||||||
The Clean Air Act created marketable commodities called emission allowances under the acid rain program, the NOx budget trading program, and the CAIR. Environmental regulations, including those relating to the timing of the installation of pollution control equipment, fuel mix, and the level of operations will have a significant impact on the number of allowances required for ongoing operations. The CAIR uses the acid rain program's allowances for SO2 emissions and created annual and ozone season NOx allowances. Ameren and Ameren Missouri expect to have adequate allowances for 2013 to avoid needing to make external purchases to comply with these programs. | ||||||||||||||||||||||||||||
Greenhouse Gas Regulation | ||||||||||||||||||||||||||||
State and federal authorities, including the United States Congress, have considered initiatives to limit greenhouse gas emissions. Potential impacts from any such legislation or regulation could vary, depending upon proposed CO2 emission limits, the timing of implementation of those limits, the method of distributing any allowances, the degree to which offsets are allowed and available, and provisions for cost-containment measures, such as a “safety valve” provision that provides a maximum price for emission allowances. As a result of our fuel portfolio, our emissions of greenhouse gases vary among our energy centers, but coal-fired power plants are significant sources of CO2. The enactment of a law that restricts emissions of CO2 or requires energy centers to purchase allowances for CO2 emissions could result in a significant rise in rates for electricity and thereby household costs. The burden could fall particularly hard on electricity consumers and upon the economy in the Midwest because of the region's reliance on electricity generated by coal-fired power plants. Natural gas emits about half as much CO2 as coal when burned to produce electricity. Therefore, greenhouse gas regulations could cause the conversion of coal-fired power plants to natural gas, or the construction of new natural gas-fired plants to replace coal-fired power plants. As a result, economy wide shifts to natural gas as a fuel source for electricity generation also could affect the cost of heating for our utility customers and many industrial processes that use natural gas. | ||||||||||||||||||||||||||||
In December 2009, the EPA issued its “endangerment finding” under the Clean Air Act, which stated that greenhouse gas emissions, including CO2, endanger human health and welfare and that emissions of greenhouse gases from motor vehicles contribute to that endangerment. In March 2010, the EPA issued a determination that greenhouse gas emissions from stationary sources, such as power plants, would be subject to regulation under the Clean Air Act effective the beginning of 2011. As a result of these actions, we are required to consider the emissions of greenhouse gases in any air permit application. | ||||||||||||||||||||||||||||
Recognizing the difficulties presented by regulating at once virtually all emitters of greenhouse gases, the EPA issued the “Tailoring Rule,” which established new higher emission thresholds beginning in January 2011, for regulating greenhouse gas emissions from stationary sources, such as power plants. The rule requires any source that already has an operating permit to have greenhouse-gas-specific provisions added to its permit upon renewal. Currently, all Ameren energy centers have operating permits that, when renewed, may be modified to address greenhouse gas emissions. The Tailoring Rule also provides that if projects performed at major sources result in an increase in emissions of greenhouse gases over an applicable annual threshold, such projects could trigger permitting requirements under the NSR programs and the application of best available control technology to address greenhouse gas emissions. New major sources are also required to obtain such a permit and to install the best available control technology if their greenhouse gas emissions exceed the applicable emissions threshold. In June 2012, the United States Court of Appeals for the District of Columbia Circuit upheld the Tailoring Rule. Industry groups and a coalition of states filed petitions in April 2013 requesting that the United States Supreme Court review the circuit court’s decision upholding the Tailoring Rule. In October 2013, the United States Supreme Court granted the petition agreeing to consider whether the Clean Air Act authorizes the EPA to regulate emissions of greenhouse gases from stationary sources, including power plants, as a result of the EPA’s determination to regulate greenhouse gas emissions from motor vehicles. A ruling is expected in 2014. | ||||||||||||||||||||||||||||
In June 2013, the Obama Administration announced that it had directed the EPA to set CO2 emissions standards for both new and existing power plants. The EPA proposed revised CO2 emissions regulations for new electricity generating units in September 2013. The proposed standards would establish separate emissions limits for new natural gas-fired plants and new coal-fired plants. In addition, the Obama Administration had directed the EPA to propose a CO2 emissions standard for existing power plants by June 2014 and to finalize such standard by June 2015. Currently, the Ameren Companies are unable to predict the outcome or impacts of such future regulations. | ||||||||||||||||||||||||||||
Recent federal court decisions have considered the application of common law causes of action, such as nuisance, to address alleged damages resulting from greenhouse gas emissions. In March 2012, the United States District Court for the Southern District of Mississippi dismissed the Comer v. Murphy Oil lawsuit, which alleged that CO2 emissions from several industrial companies, including Ameren Missouri, Genco and AERG, created atmospheric conditions that intensified Hurricane Katrina, thereby causing property damage. In May 2013, the dismissal of the lawsuit was affirmed by the United States Court of Appeals for the Fifth Circuit. | ||||||||||||||||||||||||||||
Future federal and state legislation or regulations that mandate limits on the emission of greenhouse gases would likely result in significant increases in capital expenditures and operating costs, which, in turn, could lead to increased liquidity needs and higher financing costs. These compliance costs could be prohibitive at some of our energy centers as the expected return from these investments, at current market prices for energy and capacity, might not justify the required capital expenditures or their continued operation, which could result in the impairment of long-lived assets. To the extent Ameren Missouri requests recovery of these costs through rates, its regulators might delay or deny timely recovery of these costs. As a result, mandatory limits on the emission of greenhouse gases could have a material adverse impact on Ameren's and Ameren Missouri's results of operations, financial position, and liquidity. | ||||||||||||||||||||||||||||
NSR and Clean Air Litigation | ||||||||||||||||||||||||||||
The EPA is engaged in an enforcement initiative to determine whether coal-fired power plants failed to comply with the requirements of the NSR and NSPS provisions under the Clean Air Act when the plants implemented modifications. The EPA's inquiries focus on whether projects performed at power plants triggered various permitting requirements and the installation of pollution control equipment. | ||||||||||||||||||||||||||||
Commencing in 2005, Genco received a series of information requests from the EPA pursuant to Section 114(a) of the Clean Air Act. The requests sought detailed operating and maintenance history data with respect to Genco's Coffeen, Hutsonville, Meredosia, Newton, and Joppa energy centers and AERG's E.D. Edwards and Duck Creek energy centers. In August 2012, Genco received a Notice of Violation from the EPA alleging violations of permitting requirements including Title V of the Clean Air Act. The EPA contends that projects performed in 1997, 2006, and 2007 at Genco's Newton energy center violated federal law. Ameren believes its defenses to the allegations at Genco described in the Notice of Violation are meritorious. A recent decision by the United States Court of Appeals for the Seventh Circuit held that similar claims older than five years were barred by the statute of limitations. If not reversed or overturned, this decision may provide an additional defense to the allegations in the Newton energy center Notice of Violation. Ameren is unable to predict the outcome of this matter. | ||||||||||||||||||||||||||||
Following the issuance of a Notice of Violation in January 2011, the Department of Justice on behalf of the EPA filed a complaint against Ameren Missouri in the United States District Court for the Eastern District of Missouri. The EPA's complaint, as amended in October 2013, alleges that in performing projects at its Rush Island coal-fired energy center in 2007 and 2010, Ameren Missouri violated provisions of the Clean Air Act and Missouri law. In January 2012, the district court granted, in part, Ameren Missouri's motion to dismiss various aspects of the EPA's penalty claims. The EPA's claims for unspecified injunctive relief remain. Trial in this matter is currently scheduled for January 2015. Ameren Missouri believes its defenses are meritorious and will defend itself vigorously. However, there can be no assurances that it will be successful in its efforts. | ||||||||||||||||||||||||||||
Ultimate resolution of these matters could have a material adverse impact on the future results of operations, financial position, and liquidity of Ameren and Ameren Missouri. A resolution could result in increased capital expenditures for the installation of pollution control equipment, increased operations and maintenance expenses, and penalties. We are unable to predict the ultimate resolution of these matters or the costs that might be incurred. | ||||||||||||||||||||||||||||
Clean Water Act | ||||||||||||||||||||||||||||
In March 2011, the EPA announced a proposed rule applicable to cooling water intake structures at existing power plants that have the ability to withdraw more than 2 million gallons of water per day from a body of water and use at least 25% of that water exclusively for cooling. Under the proposed rule, affected facilities would be required either to meet mortality limits for aquatic life impinged on the plant's intake screens or to reduce intake velocity to a specified level. The proposed rule also requires existing power plants to meet site-specific entrainment standards or to reduce the cooling water intake flow commensurate with the intake flow of a closed-cycle cooling system. The final rule is scheduled to be issued in November 2013, with compliance expected within eight years thereafter. All coal-fired, nuclear, and combined cycle energy centers at Ameren, Ameren Missouri and AER with cooling water systems are subject to this proposed rule. The proposed rule did not mandate cooling towers at existing facilities, as other technology options potentially could meet the site-specific standards. The final rule could have an adverse effect on our results of operations, financial position, and liquidity if its implementation requires the installation of cooling towers or extensive modifications to the cooling water systems at our energy centers. | ||||||||||||||||||||||||||||
In April 2013, the EPA announced its proposal to revise the effluent limitation guidelines applicable to steam electric generating units under the Clean Water Act. Effluent limitation guidelines are national standards for wastewater discharges to surface water that are based on the effectiveness of available control technology. The proposed revision targets wastewater streams associated with fluegas desulfurization (i.e. scrubbers), fly ash, bottom ash, fluegas mercury control, CCR leachate from landfills and impoundments, nonchemical metal cleaning, and gasification of fuels. The EPA’s proposal identifies several alternatives for addressing these waste streams, including best management practices for CCR impoundments. The EPA’s proposed rule raised several compliance options that would prohibit effluent discharges of certain, but not all, waste streams and impose more stringent limitations on certain components in wastewater discharges from power plants. If enacted as proposed, Ameren Missouri and AER would be subject to the revised limitations beginning as early as July 1, 2017, but no later than July 1, 2022. We are reviewing the proposed rule and evaluating its potential impact on our operations if enacted as proposed. The EPA expects to issue a final rule in 2014. | ||||||||||||||||||||||||||||
Remediation | ||||||||||||||||||||||||||||
We are involved in a number of remediation actions to clean up hazardous waste sites as required by federal and state law. Such statutes require that responsible parties fund remediation actions regardless of their degree of fault, the legality of original disposal, or the ownership of a disposal site. Ameren Missouri and Ameren Illinois have each been identified by the federal or state governments as a potentially responsible party (PRP) at several contaminated sites. | ||||||||||||||||||||||||||||
As part of the transfer of generation assets by our rate-regulated utility operations in Illinois to Genco in May 2000 and to AERG in October 2003, Ameren Illinois’ predecessor companies contractually agreed to indemnify Genco and AERG for claims relating to pre-existing environmental conditions at the transferred sites. The plant transfer agreements between both Genco and Ameren Illinois and AERG and Ameren Illinois will be amended as part of the transaction agreement for Ameren to divest New AER to IPH. The agreements will specify that Medina Valley will assume any environmental liabilities associated with the Meredosia and Hutsonville energy centers. The agreements will also specify that Genco and AERG will no longer be indemnified by Ameren Illinois with respect to the environmental liabilities associated with Genco’s Newton and Coffeen energy centers and AERG’s E.D. Edwards and Duck Creek energy centers. See Note 2 - Divestiture Transactions and Discontinued Operations for additional information regarding Ameren’s divestiture of New AER. | ||||||||||||||||||||||||||||
As of September 30, 2013, Ameren Illinois owned or was otherwise responsible for 44 former MGP sites in Illinois. These sites are in various stages of investigation, evaluation, remediation, and closure. Based on current estimated plans, Ameren Illinois could substantially conclude remediation efforts at most of these sites by 2018. The ICC permits Ameren Illinois to recover remediation and litigation costs associated with its former MGP sites from its electric and natural gas utility customers through environmental adjustment rate riders. To be recoverable, such costs must be prudently and properly incurred. Costs are subject to annual review by the ICC. | ||||||||||||||||||||||||||||
As of September 30, 2013, Ameren Missouri has one remaining former MGP site for which remediation is scheduled. Remediation is complete at the other Ameren Missouri former MGP sites. Ameren Missouri does not currently have a rate rider mechanism that permits it to recover from utility customers remediation costs associated with MGP sites. | ||||||||||||||||||||||||||||
The following table presents, as of September 30, 2013, the estimated obligation to complete the remediation of these former MGP sites. | ||||||||||||||||||||||||||||
Estimate | Recorded | |||||||||||||||||||||||||||
Low | High | Liability(a) | ||||||||||||||||||||||||||
Ameren | $ | 251 | $ | 337 | $ | 251 | ||||||||||||||||||||||
Ameren Missouri | 5 | 6 | 5 | |||||||||||||||||||||||||
Ameren Illinois | 246 | 331 | 246 | |||||||||||||||||||||||||
(a) | Recorded liability represents the estimated minimum probable obligations, as no other amount within the range was a better estimate. | |||||||||||||||||||||||||||
The scope and extent to which these former MGP sites are remediated may increase as remediation efforts continue. Considerable uncertainty remains in these estimates as many factors can influence the ultimate actual costs, including site specific unanticipated underground structures, the degree to which groundwater is encountered, regulatory changes, local ordinances, and site accessibility. The actual costs may vary substantially from these estimates. | ||||||||||||||||||||||||||||
Ameren Illinois utilized an off-site landfill, which Ameren Illinois did not own, in connection with its operation of the Coffeen energy center prior to the formation of Genco. While not currently mandated, Ameren Illinois may be required to perform certain remediation activities associated with that landfill. As of September 30, 2013, Ameren Illinois estimated the obligation related to the cleanup at $0.5 million to $6 million. Ameren Illinois recorded a liability of $0.5 million to represent its estimated minimum obligation for this site, as no other amount within the range was a better estimate. Ameren Illinois is also responsible for the cleanup of a landfill, underground storage tanks, and a water treatment plant in Illinois. As of September 30, 2013, Ameren Illinois recorded a liability of $0.8 million to represent its estimate of the obligation for these sites. | ||||||||||||||||||||||||||||
Ameren Missouri has responsibility for the investigation and potential cleanup of two waste sites in Missouri as a result of federal agency mandates. One of the cleanup sites is a former coal tar distillery located in St. Louis, Missouri. In 2008, the EPA issued an administrative order to Ameren Missouri pertaining to this distillery operated by Koppers Company or its predecessor and successor companies. Ameren Missouri is the current owner of the site, but Ameren Missouri did not conduct any of the manufacturing operations involving coal tar or its byproducts. Ameren Missouri, along with two other PRPs, is currently performing a site investigation. As of September 30, 2013, Ameren Missouri estimated its obligation at $2 million to $5 million. Ameren Missouri recorded a liability of $2 million to represent its estimated minimum obligation, as no other amount within the range was a better estimate. Ameren Missouri's other active federal agency-mandated cleanup site in Missouri is a site in Cape Girardeau. Ameren Missouri was a customer of an electrical equipment repair and disposal company that previously operated a facility at this site. A trust was established in the early 1990s by several businesses and governmental agencies to fund the investigation and cleanup of this site, which was completed in 2005. Ameren Missouri anticipates that this trust fund will be sufficient to complete the remaining adjacent off-site cleanup, and it therefore has no recorded liability at September 30, 2013, for this site. | ||||||||||||||||||||||||||||
Ameren Missouri also has a federal agency mandate to complete an investigation for a site in Illinois. In 2000, the EPA notified Ameren Missouri and numerous other companies, including Solutia, that former landfills and lagoons in Sauget, Illinois, may contain soil and groundwater contamination. These sites are known as Sauget Area 2. From about 1926 until 1976, Ameren Missouri operated an energy center adjacent to Sauget Area 2. Ameren Missouri currently owns a parcel of property that was once used as a landfill. Under the terms of an Administrative Order on Consent, Ameren Missouri joined with other PRPs to evaluate the extent of potential contamination with respect to Sauget Area 2. | ||||||||||||||||||||||||||||
The Sauget Area 2 investigations overseen by the EPA have been completed. The results have been submitted to the EPA, and a record of decision is expected in 2014. Once the EPA has approved the proposed site remedies, it will begin negotiations with various PRPs regarding implementation. Over the last several years, numerous other parties have joined the PRP group. In addition, Pharmacia Corporation and Monsanto Company have agreed to assume the liabilities related to Solutia's former chemical waste landfill in Sauget Area 2. As of September 30, 2013, Ameren Missouri estimated its obligation related to Sauget Area 2 at $0.3 million to $10 million. Ameren Missouri recorded a liability of $0.3 million to represent its estimated minimum obligation, as no other amount within the range was a better estimate. | ||||||||||||||||||||||||||||
In December 2012, Ameren Missouri signed an administrative order with the EPA and agreed to investigate soil and groundwater conditions at an Ameren Missouri owned substation in St. Charles, Missouri. As of September 30, 2013, Ameren Missouri estimated the obligation related to the cleanup at $1.6 million to $4.5 million. Ameren Missouri recorded a liability of $1.6 million to represent its estimated minimum obligation for this site, as no other amount within the range was a better estimate. | ||||||||||||||||||||||||||||
Our operations or those of our predecessor companies involve the use of, disposal of, and in appropriate circumstances, the cleanup of substances regulated under environmental laws. We are unable to determine whether such practices will result in future environmental commitments or will affect our results of operations, financial position, or liquidity. | ||||||||||||||||||||||||||||
Ash Management | ||||||||||||||||||||||||||||
There has been activity at both state and federal levels regarding additional regulation of CCR. In May 2010, the EPA announced proposed new regulations regarding the regulatory framework for the management and disposal of CCR, which could affect future disposal and handling costs at our energy centers. Those proposed regulations include two options for managing CCRs under either solid or hazardous waste regulations, but either alternative would allow for some continued beneficial uses, such as recycling of CCR without classifying it as waste. As part of its proposal, the EPA is considering alternative regulatory approaches that require coal-fired power plants either to close surface impoundments, such as ash ponds, or to retrofit such facilities with liners. Existing impoundments and landfills used for the disposal of CCR would be subject to groundwater monitoring requirements and requirements related to closure and postclosure care under the proposed regulations. The EPA announced that its April 2013 proposed revisions to the effluent limitations applicable to steam electric generating units would apply to ash ponds and CCR management and that it intended to align this proposal with the CCR rules proposed in May 2010. Additionally, in January 2010, the EPA announced its intent to develop regulations establishing financial responsibility requirements for the electric generation industry, among other industries, and it specifically discussed CCR as a reason for developing the new requirements. Ameren, Ameren Missouri and AER are currently evaluating all of the proposed regulations to determine whether current management of CCR, including beneficial reuse, and the use of the ash ponds should be altered. Ameren, Ameren Missouri and AER are evaluating the potential costs associated with compliance with the proposed regulation of CCR impoundments and landfills, which could be material, if such regulations are adopted. See Note 2 - Divestiture Transactions and Discontinued Operations for information regarding AER’s AROs, which include those related to CCR storage facilities. | ||||||||||||||||||||||||||||
The Illinois EPA has issued violation notices with respect to groundwater conditions existing at Genco’s ash pond systems. AER filed a proposed rulemaking with the Illinois Pollution Control Board which, if approved, would provide for the systematic and eventual closure of ash ponds. In October 2013, the Illinois EPA filed a proposed rulemaking with the Illinois Pollution Control Board. AER has stayed its rulemaking efforts to allow the Illinois EPA proposed rulemaking to proceed. The rulemaking process could take several years to complete. During the first quarter of 2013, Genco and AERG revised their ARO fair value estimates relating to their ash ponds to reflect expected retirement dates. See Note 1 - Summary of Significant Accounting Policies for additional information related to our asset retirement obligations. | ||||||||||||||||||||||||||||
Pumped-storage Hydroelectric Facility Breach | ||||||||||||||||||||||||||||
In December 2005, there was a breach of the upper reservoir at Ameren Missouri's Taum Sauk pumped-storage hydroelectric energy center. This resulted in significant flooding in the local area, which damaged a state park. The rebuilt Taum Sauk energy center became fully operational in April 2010. | ||||||||||||||||||||||||||||
Ameren Missouri had liability insurance coverage for the Taum Sauk incident, subject to certain limits and deductibles. As of September 30, 2013, Ameren Missouri had an insurance receivable balance of $68 million. Ameren Missouri's results of operations, financial position and liquidity could be adversely affected if its remaining liability insurance claims are not paid by insurers. | ||||||||||||||||||||||||||||
In June 2010, Ameren Missouri sued an insurance company that was providing Ameren Missouri with liability coverage on the date of the Taum Sauk incident. In the litigation, filed in the United States District Court for the Eastern District of Missouri, Ameren Missouri claimed that the insurance company breached its duty to indemnify Ameren Missouri for the losses resulting from the incident. In January 2011, the district court ruled that the parties must first pursue alternative dispute resolution and enforced the forum selection clause of their coverage agreement. The forum selection clause requires use of New York law and effectively requires mandatory arbitration. Ameren Missouri appealed the January 2011 ruling to the United States Court of Appeals for the Eighth Circuit. In August 2012, the court of appeals remanded the case to the district court for consideration of whether Missouri public policy voids the forum selection clause. In September 2013, the district court ruled that Missouri public policy voids the forum selection clause. | ||||||||||||||||||||||||||||
Separately, in April 2012, Ameren Missouri sued a second insurance company that was providing Ameren Missouri with liability coverage on the date of the Taum Sauk incident. In the April 2012 litigation, which is pending in the United States District Court for the Eastern District of Missouri, Ameren Missouri claimed the insurance company breached its duty to indemnify Ameren Missouri for the losses resulting from the incident. The insurance company filed a motion to compel arbitration, which the district court denied. In April 2013, the United States Court of Appeals for the Eighth Circuit affirmed the district court’s denial of the insurer’s motion and remanded the case to the district court. | ||||||||||||||||||||||||||||
Asbestos-related Litigation | ||||||||||||||||||||||||||||
Ameren, Ameren Missouri and Ameren Illinois have been named, along with numerous other parties, in a number of lawsuits filed by plaintiffs claiming varying degrees of injury from asbestos exposure. Most have been filed in the Circuit Court of Madison County, Illinois. The total number of defendants named in each case varies with the average number of parties being 78 as of September 30, 2013. Each lawsuit seeks unspecified damages that, if awarded at trial, typically would be shared among the various defendants. | ||||||||||||||||||||||||||||
The claims filed against Ameren, Ameren Missouri and Ameren Illinois allege injury from asbestos exposure during the plaintiffs' activities at our present or former energy centers. Former CIPS energy centers are now owned by Genco, and former CILCO energy centers are now owned by AERG. As a condition to the transfer of ownership of the CIPS and CILCO energy centers, CIPS and CILCO, now Ameren Illinois, contractually agreed to indemnify Genco and AERG, respectively, for liabilities associated with asbestos-related claims arising or existing from activities prior to the transfer. The plant transfer agreement between Genco and Ameren Illinois and the plant transfer agreement between AERG and Ameren Illinois each will be amended pursuant to the transaction agreement in which Ameren agrees to divest New AER to IPH. The amended plant transfer agreements will provide that Ameren Illinois will continue to retain asbestos exposure-related liabilities for claims arising or existing from activities prior to the transfer of the ownership of the CIPS and CILCO energy centers to Genco and AERG. IPH will be responsible for any asbestos-related claims arising from activities that occur after IPH takes ownership of New AER. Any asbestos-related claims arising solely from activities post transfer of the energy centers from CIPS and CILCO to Genco and AERG, respectively, but prior to IPH taking ownership of New AER, of which there are currently none, will be retained by Ameren. See Note 2 - Divestiture Transactions and Discontinued Operations for additional information regarding Ameren's divestiture of AER. | ||||||||||||||||||||||||||||
The following table presents the pending asbestos-related lawsuits filed against the Ameren Companies as of September 30, 2013: | ||||||||||||||||||||||||||||
Ameren | Ameren | Ameren | Total(a) | |||||||||||||||||||||||||
Missouri | Illinois | |||||||||||||||||||||||||||
1 | 55 | 63 | 85 | |||||||||||||||||||||||||
(a) | Total does not equal the sum of the subsidiary unit lawsuits because some of the lawsuits name multiple Ameren entities as defendants. | |||||||||||||||||||||||||||
At September 30, 2013, Ameren, Ameren Missouri and Ameren Illinois had liabilities of $15 million, $7 million, and $8 million, respectively, recorded to represent their best estimate of their obligations related to asbestos claims. | ||||||||||||||||||||||||||||
Ameren Illinois has a tariff rider to recover the costs of IP asbestos-related litigation claims, subject to the following terms: 90% of cash expenditures in excess of the amount included in base electric rates are to be recovered from a trust fund that was established when Ameren acquired IP. At September 30, 2013, the trust fund balance was $23 million, including accumulated interest. If cash expenditures are less than the amount in base rates, Ameren Illinois will contribute 90% of the difference to the trust fund. Once the trust fund is depleted, 90% of allowed cash expenditures in excess of base rates will be recovered through charges assessed to customers under the tariff rider. The rider will permit recovery from customers within IP’s historical service territory. | ||||||||||||||||||||||||||||
Ameren Illinois Municipal Taxes | ||||||||||||||||||||||||||||
Ameren Illinois received tax liability notices from the City of O'Fallon, Illinois relating to prior-period electric and natural gas municipal taxes. The city alleges that Ameren Illinois failed to collect prior-period taxes from more than 2,400 accounts primarily in annexed areas for the period 2004 through 2012. In July 2013, the O’Fallon city administrator issued an order stating that Ameren Illinois was liable to the City of O’Fallon for $4 million. In August 2013, Ameren Illinois filed an appeal and a stay of the O’Fallon city administrator’s order to the St. Clair County Circuit Court. In addition, in December 2012, the City of Peoria issued a tax liability notice alleging that Ameren Illinois failed to collect prior-period municipal taxes from certain accounts. In September 2013, a hearing officer issued an order stating that Ameren Illinois was liable to the City of Peoria for $0.5 million. Ameren Illinois plans to file an appeal and a stay of the order to the Peoria County Circuit Court. Ameren Illinois believes its defenses to the allegations are meritorious and will defend itself vigorously. As of September 30, 2013, Ameren Illinois estimated its obligation at $1 million to $5 million. Ameren Illinois recorded a liability of $1 million to represent its estimated minimum obligation to the City of O'Fallon and the City of Peoria, as no other amount within the range was a better estimate. | ||||||||||||||||||||||||||||
In addition, at the end of 2012, five other cities issued tax liability notices alleging that Ameren Illinois failed to collect prior-period taxes from certain accounts. At this time, it is premature in Ameren Illinois' review of the additional notices received at the end of 2012 to reasonably estimate any likelihood of loss. |
Callaway_Energy_Center
Callaway Energy Center | 9 Months Ended |
Sep. 30, 2013 | |
Nuclear Waste Matters [Abstract] | ' |
CALLAWAY ENERGY CENTER | ' |
CALLAWAY ENERGY CENTER | |
Under the NWPA, the DOE is responsible for disposing of spent nuclear fuel from the Callaway energy center and other commercial nuclear energy centers. Under the NWPA, Ameren Missouri and other companies that own and operate those energy centers are responsible for paying the disposal costs. The NWPA established the fee that these companies pay the federal government for disposing of the spent nuclear fuel at one mill, or one-tenth of one cent, for each kilowatthour generated by those plants and sold. The NWPA also requires the DOE to review the nuclear waste fee against the cost of the nuclear waste disposal program and to propose to the United States Congress any fee adjustment necessary to offset the costs of the program. As required by the NWPA, Ameren and other companies have entered into standard contracts with the DOE, which is the agency responsible for implementing the NWPA. Consistent with the NWPA and its standard contract, Ameren Missouri collects one mill from its electric customers for each kilowatthour of electricity that it generates and sells from its Callaway energy center. | |
Both the NWPA and the standard contract stated that the federal government would begin to dispose of spent nuclear fuel by 1998, however, no federal storage facility currently exists. Ameren Missouri has sufficient installed capacity at its Callaway energy center to store the spent nuclear fuel generated at Callaway through 2020 and has the capability for additional storage capacity for spent nuclear fuel generated through the end of the energy center’s current licensed life. | |
Until January 2009, the DOE program provided for spent nuclear fuel disposal to take place at a geologic repository to be constructed at Yucca Mountain, Nevada. In January 2009, the federal government announced that a repository at Yucca Mountain was unworkable and took steps to terminate the Yucca Mountain program, while acknowledging the federal government’s continuing obligation to dispose of companies’ spent nuclear fuel. In January 2012, an advisory commission established by the DOE issued its report of recommendations for the storage and disposal of spent nuclear fuel. The recommendations covered topics such as the approach to siting future nuclear waste management facilities, the transport and storage of spent fuel and high-level waste, options for waste disposal, institutional arrangements for managing spent nuclear fuel and high-level wastes, and changes needed in the handling of nuclear waste fees and of the Nuclear Waste Fund. | |
In January 2013, the DOE issued its plan for the management and disposal of spent nuclear fuel in response to the recommendation contained in the advisory commission's report. The DOE's plan calls for a pilot interim storage facility to begin operation with an initial focus on accepting spent nuclear fuel from shutdown reactor sites by 2021. By 2025, a larger interim storage facility would be available and would be co-located with the pilot facility. The plan also proposes to site a permanent geological repository to begin operation by 2048. The DOE's delay in carrying out its obligation to dispose of spent nuclear fuel from the Callaway energy center is not expected to adversely affect the continued operation of the energy center. | |
As a result of the DOE's failure to begin to dispose of the spent nuclear fuel from nuclear energy centers and fulfill its contractual obligations, Ameren Missouri and other nuclear energy center owners have sued the DOE to recover costs incurred for ongoing storage of their spent fuel. Ameren Missouri filed a breach of contract lawsuit to recover costs that it incurred through 2009. This amount included the cost of reracking the Callaway energy center’s spent fuel pool, as well as certain NRC fees, and Missouri ad valorem taxes that Ameren Missouri would not have incurred had DOE performed its contractual obligations. In June 2011, the parties reached a settlement that included an annual reimbursement of Ameren Missouri’s spent fuel storage and related costs through at least 2013. In March 2013, Ameren Missouri submitted its 2012 costs to the DOE for reimbursement under the settlement agreement. Ameren Missouri expects to receive the 2012 cost reimbursement of $6 million during the fourth quarter of 2013. These costs were recorded in “Miscellaneous accounts and notes receivable” on Ameren’s and Ameren Missouri’s September 30, 2013 balance sheets. | |
In December 2011, Ameren Missouri filed a license extension application with the NRC to extend its Callaway energy center's operating license from 2024 to 2044. There is no deadline by which the NRC must act on this application. Among the rules that the NRC has historically relied upon in approving license extensions are rules dealing with the storage of spent nuclear fuel at the reactor site and with the NRC's confidence that permanent disposal of spent nuclear fuel will be available when needed. In a June 2012 decision, the United States Court of Appeals for the District of Columbia Circuit vacated these rules and remanded the case to the NRC, holding that the NRC's obligations under the National Environmental Policy Act required a more thorough environmental analysis in support of the NRC's waste confidence decision. In June 2012, a number of groups petitioned the NRC to suspend final licensing decisions in certain NRC licensing proceedings, including the Callaway energy center license extension, until the NRC completed its proceedings on the vacated rules. In August 2012, the NRC stated that it would not issue licenses dependent on the vacated rules until it appropriately addressed the court's remand. In September 2012, the NRC directed its staff to issue, within two years, a new waste confidence final environmental impact statement and a final rule to address the court's ruling. The newly created Waste Confidence Directorate within NRC now oversees the drafting of a new waste confidence environmental impact statement and rule, and its schedule presently provides for issuance of the final environmental impact statement and final rule by no later than September 2014. Consistent with its schedule, the NRC, on September 13, 2013, issued for public comment the draft waste confidence generic environmental impact statement and its proposed waste confidence rule. If the Callaway energy center's license is extended, additional spent fuel storage will be required. Ameren Missouri plans to install a dry spent fuel storage facility at its Callaway energy center and intends to begin transferring spent fuel assemblies to this facility by 2016. | |
Electric utility rates charged to customers provide for the recovery of the Callaway energy center's decommissioning costs, which include decontamination, dismantling, and site restoration costs, over an assumed 40-year life of the nuclear center, ending with the expiration of the energy center's current operating license in 2024. It is assumed that the Callaway energy center site will be decommissioned through the immediate dismantlement method and removed from service. Ameren and Ameren Missouri have recorded an ARO for the Callaway energy center decommissioning costs at fair value, which represents the present value of estimated future cash outflows. Decommissioning costs are included in the costs of service used to establish electric rates for Ameren Missouri's customers. These costs amounted to $7 million in each of the years 2013, 2012, and 2011. Every three years, the MoPSC requires Ameren Missouri to file an updated cost study and funding analysis for decommissioning its Callaway energy center. Electric rates may be adjusted at such times to reflect changed estimates. If Ameren Missouri's operating license extension application is approved by the NRC, a revised funding analysis will be prepared and the rates charged to customers will be adjusted accordingly to reflect the operating license extension at the time of the next triennial cost study and funding analysis is approved by the MoPSC. Amounts collected from customers are deposited in an external trust fund to provide for the Callaway energy center's decommissioning. If the assumed return on trust assets is not earned, we believe that it is probable that any such earnings deficiency will be recovered in rates. The fair value of the nuclear decommissioning trust fund for Ameren Missouri's Callaway energy center is reported as "Nuclear decommissioning trust fund" in Ameren's and Ameren Missouri's balance sheets. This amount is legally restricted and may be used only to fund the costs of nuclear decommissioning. Changes in the fair value of the trust fund are recorded as an increase or decrease to the nuclear decommissioning trust fund, with an offsetting adjustment to the related regulatory liability. | |
See Note 3 - Rate and Regulatory Matters for additional information related to the Callaway energy center. |
Retirement_Benefits
Retirement Benefits | 9 Months Ended | |||||||||||||||||||||||||||||||
Sep. 30, 2013 | ||||||||||||||||||||||||||||||||
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract] | ' | |||||||||||||||||||||||||||||||
RETIREMENT BENEFITS | ' | |||||||||||||||||||||||||||||||
RETIREMENT BENEFITS | ||||||||||||||||||||||||||||||||
Ameren’s pension and postretirement plans are funded in compliance with income tax regulations and to meet federal funding or regulatory requirements. As a result, Ameren expects to fund its pension plans at a level equal to the greater of the pension expense or the legally required minimum contribution. Considering Ameren’s assumptions at September 30, 2013, the plan’s estimated investment performance through September 30, 2013, and Ameren’s pension funding policy, Ameren expects to make annual contributions of $50 million to $150 million in each of the next five years, with aggregate estimated contributions of $475 million. These amounts are estimates which may change with actual investment performance, changes in interest rates, any pertinent changes in government regulations, and any voluntary contributions. Our policy for postretirement benefits is primarily to fund the voluntary employee’s beneficiary association trusts to match the annual postretirement expense. | ||||||||||||||||||||||||||||||||
The following table presents the components of the net periodic benefit cost for Ameren’s pension and postretirement benefit plans for the three and nine months ended September 30, 2013, and 2012: | ||||||||||||||||||||||||||||||||
Pension Benefits (a) | Postretirement Benefits (a) | |||||||||||||||||||||||||||||||
Three Months | Nine Months | Three Months | Nine Months | |||||||||||||||||||||||||||||
2013 | 2012 | 2013 | 2012 | 2013 | 2012 | 2013 | 2012 | |||||||||||||||||||||||||
Service cost | $ | 23 | $ | 20 | $ | 69 | $ | 61 | $ | 6 | $ | 5 | $ | 17 | $ | 16 | ||||||||||||||||
Interest cost | 40 | 42 | 121 | 125 | 11 | 12 | 34 | 36 | ||||||||||||||||||||||||
Expected return on plan assets | (54 | ) | (52 | ) | (162 | ) | (156 | ) | (16 | ) | (14 | ) | (47 | ) | (42 | ) | ||||||||||||||||
Amortization of: | ||||||||||||||||||||||||||||||||
Transition obligation | — | — | — | — | — | 1 | — | 1 | ||||||||||||||||||||||||
Prior service cost (benefit) | (1 | ) | (1 | ) | (3 | ) | (3 | ) | (1 | ) | (1 | ) | (3 | ) | (3 | ) | ||||||||||||||||
Actuarial loss | 23 | 19 | 69 | 56 | 2 | 1 | 6 | 3 | ||||||||||||||||||||||||
Net periodic benefit cost | $ | 31 | $ | 28 | $ | 94 | $ | 83 | $ | 2 | $ | 4 | $ | 7 | $ | 11 | ||||||||||||||||
(a) | Excludes the EEI plans as they are included in discontinued operations. | |||||||||||||||||||||||||||||||
Ameren Missouri and Ameren Illinois are responsible for their respective shares of Ameren’s pension and postretirement costs. The following table presents the pension costs and the postretirement benefit costs incurred for the three and nine months ended September 30, 2013, and 2012: | ||||||||||||||||||||||||||||||||
Pension Costs | Postretirement Costs | |||||||||||||||||||||||||||||||
Three Months | Nine Months | Three Months | Nine Months | |||||||||||||||||||||||||||||
2013 | 2012 | 2013 | 2012 | 2013 | 2012 | 2013 | 2012 | |||||||||||||||||||||||||
Ameren Missouri | $ | 18 | $ | 16 | $ | 54 | $ | 48 | $ | 2 | $ | 2 | $ | 7 | $ | 7 | ||||||||||||||||
Ameren Illinois | 10 | 9 | 31 | 27 | (b) | 1 | (b) | 3 | ||||||||||||||||||||||||
Other | 3 | 3 | 9 | 8 | (b) | 1 | (b) | 1 | ||||||||||||||||||||||||
Ameren(a) | $ | 31 | $ | 28 | $ | 94 | $ | 83 | $ | 2 | $ | 4 | $ | 7 | $ | 11 | ||||||||||||||||
(a) | Includes amounts for Ameren registrants and nonregistrant subsidiaries, but excludes the EEI plans as they are included in discontinued operations. | |||||||||||||||||||||||||||||||
(b) | Less than $1 million. |
Segment_Information
Segment Information | 9 Months Ended | ||||||||||||||||||||
Sep. 30, 2013 | |||||||||||||||||||||
Segment Reporting [Abstract] | ' | ||||||||||||||||||||
SEGMENT INFORMATION | ' | ||||||||||||||||||||
SEGMENT INFORMATION | |||||||||||||||||||||
Ameren has three reportable segments: Ameren Missouri, Ameren Illinois, and Merchant Generation. The Ameren Missouri segment for both Ameren and Ameren Missouri includes all the operations of Ameren Missouri’s business as described in Note 1 - Summary of Significant Accounting Policies. The Ameren Illinois segment for both Ameren and Ameren Illinois includes all of the operations of Ameren Illinois’ business as described in Note 1 - Summary of Significant Accounting Policies. The Merchant Generation segment for Ameren consists primarily of the operations or activities of AER, including Genco, EEI, AERG, and Marketing Company. Ameren intends to divest its Merchant Generation segment and, therefore, has excluded that segment’s information below. See Note 2 - Divestiture Transactions and Discontinued Operations for information regarding the Merchant Generation segment. The category called Other primarily includes Ameren parent company activities, Ameren Services, and ATXI. The Other category also includes activities previously included in the Merchant Generation segment that will be retained by Ameren after the divestiture of New AER and the sale of the Elgin, Gibson City, and Grand Tower gas-fired energy centers are complete. See Note 2 - Divestiture Transactions and Discontinued Operations for information regarding the assets and liabilities to be retained by Ameren after the divestitures. | |||||||||||||||||||||
The following table presents information about the revenues and specified items included in net income attributable to Ameren Corporation from continuing operations for the three and nine months ended September 30, 2013, and 2012, and total assets as of September 30, 2013, and December 31, 2012. | |||||||||||||||||||||
Three Months | Ameren | Ameren | Other | Intersegment | Consolidated | ||||||||||||||||
Missouri | Illinois | Eliminations | |||||||||||||||||||
2013 | |||||||||||||||||||||
External revenues | $ | 1,088 | $ | 547 | $ | 3 | $ | — | $ | 1,638 | |||||||||||
Intersegment revenues | 5 | — | 1 | (6 | ) | — | |||||||||||||||
Net income (loss) attributable to Ameren Corporation from continuing operations | 238 | 77 | (10 | ) | — | 305 | |||||||||||||||
2012 | |||||||||||||||||||||
External revenues | $ | 1,059 | $ | 647 | $ | 3 | $ | — | $ | 1,709 | |||||||||||
Intersegment revenues | 5 | 1 | — | (6 | ) | — | |||||||||||||||
Net income (loss) attributable to Ameren Corporation from continuing operations | 236 | 71 | 2 | — | 309 | ||||||||||||||||
Nine Months | |||||||||||||||||||||
2013 | |||||||||||||||||||||
External revenues | $ | 2,760 | $ | 1,744 | $ | 12 | $ | — | $ | 4,516 | |||||||||||
Intersegment revenues | 18 | 3 | 2 | (23 | ) | — | |||||||||||||||
Net income (loss) attributable to Ameren Corporation from continuing operations | 362 | 139 | (37 | ) | — | 464 | |||||||||||||||
2012 | |||||||||||||||||||||
External revenues | $ | 2,583 | $ | 1,935 | $ | 5 | $ | — | $ | 4,523 | |||||||||||
Intersegment revenues | 16 | 1 | 2 | (19 | ) | — | |||||||||||||||
Net income (loss) attributable to Ameren Corporation from continuing operations | 400 | 130 | (23 | ) | — | 507 | |||||||||||||||
As of September 30, 2013: | |||||||||||||||||||||
Total assets | $ | 13,231 | $ | 7,439 | $ | 1,375 | $ | (1,055 | ) | $ | 20,990 | (a) | |||||||||
As of December 31, 2012: | |||||||||||||||||||||
Total assets | $ | 13,043 | $ | 7,282 | $ | 1,228 | $ | (934 | ) | $ | 20,619 | (a) | |||||||||
(a) Excludes “Assets of discontinued operations.” See Note 2 - Divestiture Transactions and Discontinued Operations for additional information. |
Summary_Of_Significant_Account1
Summary Of Significant Accounting Policies (Policies) | 9 Months Ended |
Sep. 30, 2013 | |
Accounting Policies [Abstract] | ' |
Consolidation | ' |
The financial statements of Ameren are prepared on a consolidated basis. Ameren Missouri and Ameren Illinois have no subsidiaries, and therefore their financial statements are not prepared on a consolidated basis. All significant intercompany transactions have been eliminated. All tabular dollar amounts are in millions, unless otherwise indicated. | |
Our accounting policies conform to GAAP. Our financial statements reflect all adjustments (which include normal, recurring adjustments) that are necessary, in our opinion, for a fair presentation of our results. The preparation of financial statements in conformity with GAAP requires management to make certain estimates and assumptions. Such estimates and assumptions affect reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the dates of financial statements, and the reported amounts of revenues and expenses during the reported periods. Actual results could differ from those estimates. The results of operations of an interim period may not give a true indication of results that may be expected for a full year. These financial statements should be read in conjunction with the financial statements and the notes thereto included in the Form 10-K. | |
Earnings Per Share | ' |
Basic earnings per share is computed by dividing net income attributable to Ameren Corporation common stockholders by the weighted-average number of common shares outstanding during the period. Diluted earnings per share is computed by dividing net income attributable to common stockholders by the diluted weighted-average number of common shares outstanding during the period. Diluted earnings per share reflects the potential dilution that would occur if certain stock-based performance share units were settled. | |
Intangible Assets | ' |
Ameren and Ameren Missouri classify emission allowances and renewable energy credits as intangible assets. Ameren Illinois consumes renewable energy credits as they are purchased through the IPA procurement process and expenses them immediately. We evaluate intangible assets for impairment if events or changes in circumstances indicate that their carrying amount might be impaired. | |
At September 30, 2013, Ameren’s and Ameren Missouri’s intangible assets consisted of renewable energy credits obtained through wind and solar power purchase agreements. The book value of Ameren’s and Ameren Missouri’s renewable energy credits was $19 million and $19 million, respectively, at September 30, 2013. The book value of Ameren’s and Ameren Missouri’s renewable energy credits was $14 million and $14 million, respectively, at December 31, 2012. | |
Renewable energy credits and emission allowances are charged to purchased power expense and fuel expense, respectively, as they are used in operations. In accordance with the MoPSC's 2012 electric rate order, the majority of Ameren Missouri's amortization of intangible assets is deferred as a regulatory asset pending future recovery from customers through rates. | |
Excise Taxes | ' |
Excise taxes levied on us are reflected on Ameren Missouri electric customer bills and on Ameren Missouri and Ameren Illinois natural gas customer bills. They are recorded gross in “Operating Revenues - Electric,” “Operating Revenues - Gas” and “Operating Expenses - Taxes other than income taxes” on the statement of income or the statement of income and comprehensive income. Excise taxes reflected on Ameren Illinois electric customer bills are imposed on the consumer and are therefore not included in revenues and expenses. They are recorded as tax collections payable and included in “Taxes accrued” on the balance sheet. | |
Uncertain Tax Positions | ' |
The amount of unrecognized tax benefits (detriments) as of September 30, 2013, was $86 million, $27 million, and $(2) million, for Ameren, Ameren Missouri, and Ameren Illinois, respectively. Unrecognized tax benefits are included in “Other deferred credits and liabilities” on Ameren’s, Ameren Missouri’s, and Ameren Illinois’ September 30, 2013 balance sheets. The amount of unrecognized tax benefits (detriments) as of September 30, 2013, that would impact the effective tax rate, if recognized, was $51 million, $2 million, and $(1) million for Ameren, Ameren Missouri, and Ameren Illinois, respectively. The Ameren amount of unrecognized tax benefits that would impact the effective tax rate, if recognized, increased by $50 million primarily during the first quarter of 2013. This increase was primarily due to uncertainty related to the historical computation of Ameren’s tax basis in its stock investment in AER. | |
During the three months ended September 30, 2013, unrecognized tax benefits related to the deductibility of expenditures to maintain, replace, or improve steam or electric power generation property, along with casualty loss deductions for storm damage, were reduced by $113 million, $103 million, and $5 million, for Ameren, Ameren Missouri, and Ameren Illinois, respectively, with an offset to “Accumulated deferred income taxes, net.” This was the result of recent Internal Revenue Service guidance establishing new rules for the amount and timing of these deductions. | |
Ameren’s federal income tax returns for the years 2007 through 2011 are before the Appeals Office of the Internal Revenue Service. Ameren’s federal income tax return for the year 2012 is currently under examination. | |
It is reasonably possible that a settlement will be reached with the Appeals Office of the Internal Revenue Service in the next 12 months for the years 2007 through 2011. This settlement, which is primarily related to uncertain tax positions for research tax deductions, is expected to result in a decrease in uncertain tax benefits of $23 million, $15 million, and $- million for Ameren, Ameren Missouri, and Ameren Illinois, respectively. In addition, it is reasonably possible that other events will occur during the next 12 months that would cause the total amount of unrecognized tax benefits for the Ameren Companies to increase or decrease. However, the Ameren Companies do not believe any such increases or decreases, including the decrease from the reasonably possible Internal Revenue Service Appeals Office settlement discussed above, would be material to their results of operations, financial position, or liquidity. | |
State income tax returns are generally subject to examination for a period of three years after filing of the return. The Ameren Companies do not currently have material state income tax issues under examination, administrative appeals, or litigation. The state impact of any federal changes remains subject to examination by various states for a period of up to one year after formal notification to the states. | |
Ameren Missouri has an uncertain tax position tracker. Under Missouri’s regulatory framework, uncertain income tax positions do not reduce Ameren Missouri’s electric rate base. When an uncertain income tax position liability is resolved, the MoPSC requires, through the uncertain tax position tracker, the creation of a regulatory asset or regulatory liability to reflect the time value (using the weighted-average cost of capital included in each of the electric rate orders in effect before the tax position was resolved) of the difference between the uncertain income tax position liability that was excluded from rate base and the final tax liability. The resulting regulatory asset or liability will be amortized over three years beginning on the effective date of new rates established in the next electric rate case. | |
Noncontrolling Interest | ' |
Ameren's noncontrolling interests comprised the 20% of EEI not owned by Ameren and the preferred stock not subject to mandatory redemption of Ameren's subsidiaries. These noncontrolling interests were classified as a component of equity separate from Ameren's equity on its consolidated balance sheet. | |
Accounting and Reporting Developments | ' |
The following is a summary of recently adopted authoritative accounting guidance, as well as guidance issued but not yet adopted, that could impact the Ameren Companies. | |
Presentation of Comprehensive Income | |
In June 2011, FASB amended its guidance on the presentation of comprehensive income in financial statements. The amended guidance changed the presentation of comprehensive income in the financial statements. It requires entities to report components of comprehensive income either in a continuous statement of comprehensive income or in two separate but consecutive statements. This guidance was effective for the Ameren Companies beginning in the first quarter of 2012 with retroactive application required. The implementation of the amended guidance did not affect the Ameren Companies’ results of operations, financial position, or liquidity. | |
In February 2013, FASB amended this guidance to require an entity to provide information about the amounts reclassified out of accumulated OCI by component. In addition, an entity is required to present significant amounts reclassified out of accumulated OCI by the respective line items of net income either on the face of the statement where net income is presented or in the footnotes. This guidance was effective for the Ameren Companies beginning in the first quarter of 2013. The implementation of this amended guidance did not affect the Ameren Companies’ results of operations, financial position, or liquidity. The only amounts reclassified out of accumulated OCI for the Ameren Companies related to pension and other postretirement plan activity and derivatives. These amounts were immaterial for the three and nine months ended September 30, 2013, and therefore no additional disclosures were required. | |
Disclosures about Offsetting Assets and Liabilities | |
In December 2011, FASB issued additional authoritative accounting guidance to improve information disclosed about financial and derivative instruments. The guidance requires an entity to disclose information about offsetting and related arrangements to enable users of the financial statements to understand the effect of those arrangements on its financial position. In January 2013, FASB amended this guidance to limit the scope to derivative instruments, repurchase agreements and reverse repurchase agreements, and securities borrowing and securities lending transactions. The Ameren Companies adopted this guidance for the first quarter of 2013. The implementation of this additional guidance did not affect the Ameren Companies’ results of operations, financial positions, or liquidity, as this guidance only requires additional disclosures. See Note 7 - Derivative Financial Instruments for the required additional disclosures. | |
Presentation of an Unrecognized Tax Benefit | |
In July 2013, FASB issued additional authoritative accounting guidance to provide clarity for the financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists. The objective of this guidance is to eliminate diversity in practice related to the presentation of certain unrecognized tax benefits. It requires entities to present an unrecognized tax benefit as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward to the extent a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is available under the tax law. Currently, any unrecognized tax benefit is recorded in “Other deferred credits and liabilities” on Ameren's, Ameren Missouri's, and Ameren Illinois' balance sheets. After this guidance becomes effective, any unrecognized tax benefit will be recorded in “Accumulated deferred income taxes, net” as a reduction to the deferred tax assets for net operating loss and tax credit carryforwards on the respective balance sheets. To the extent that an unrecognized tax benefit exceeds these carryforwards, the excess would continue to be recorded in “Other deferred credits and liabilities,” on the respective balance sheets, consistent with current authoritative accounting guidance. The amended guidance will not affect the Ameren Companies' results of operations or liquidity, as this guidance is presentation-related only. This guidance will be effective for the Ameren Companies beginning in the first quarter of 2014. |
Derivative_Financial_Instrumen1
Derivative Financial Instruments Derivative Financial Instruments (Policies) | 9 Months Ended | |
Sep. 30, 2013 | ||
Derivative Instruments and Hedging Activities Disclosure [Abstract] | ' | |
Derivatives | ' | |
We use derivatives principally to manage the risk of changes in market prices for natural gas, coal, diesel, power, and uranium. Such price fluctuations may cause the following: | ||
• | an unrealized appreciation or depreciation of our contracted commitments to purchase or sell when purchase or sale prices under the commitments are compared with current commodity prices; | |
• | market values of coal, natural gas, and uranium inventories that differ from the cost of those commodities in inventory; and | |
• | actual cash outlays for the purchase of these commodities that differ from anticipated cash outlays. | |
The derivatives that we use to hedge these risks are governed by our risk management policies for forward contracts, futures, options, and swaps. Our net positions are continually assessed within our structured hedging programs to determine whether new or offsetting transactions are required. The goal of the hedging program is generally to mitigate financial risks while ensuring that sufficient volumes are available to meet our requirements. Contracts we enter into as part of our risk management program may be settled financially, settled by physical delivery, or net settled with the counterparty. |
Retirement_Benefits_Retirement
Retirement Benefits Retirement Benefits (Policies) | 9 Months Ended |
Sep. 30, 2013 | |
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract] | ' |
Retirement Benefits | ' |
Ameren’s pension and postretirement plans are funded in compliance with income tax regulations and to meet federal funding or regulatory requirements. As a result, Ameren expects to fund its pension plans at a level equal to the greater of the pension expense or the legally required minimum contribution. Considering Ameren’s assumptions at September 30, 2013, the plan’s estimated investment performance through September 30, 2013, and Ameren’s pension funding policy, Ameren expects to make annual contributions of $50 million to $150 million in each of the next five years, with aggregate estimated contributions of $475 million. These amounts are estimates which may change with actual investment performance, changes in interest rates, any pertinent changes in government regulations, and any voluntary contributions. Our policy for postretirement benefits is primarily to fund the voluntary employee’s beneficiary association trusts to match the annual postretirement expense. |
Summary_Of_Significant_Account2
Summary Of Significant Accounting Policies (Tables) | 9 Months Ended | ||||||||||||||||
Sep. 30, 2013 | |||||||||||||||||
Accounting Policies [Abstract] | ' | ||||||||||||||||
Schedule of Weighted Average Number of Common Shares Outstanding | ' | ||||||||||||||||
The following table presents Ameren’s basic and diluted earnings per share calculations and reconciles the weighted-average number of common shares outstanding to the diluted weighted-average number of common shares outstanding for the three and nine months ended September 30, 2013, and 2012: | |||||||||||||||||
Three Months | Nine Months | ||||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||||
Net income (loss) attributable to Ameren Corporation: | |||||||||||||||||
Continuing operations | $ | 305 | $ | 309 | $ | 464 | $ | 507 | |||||||||
Discontinued operations | (3 | ) | 65 | (212 | ) | (325 | ) | ||||||||||
Net income (loss) attributable to Ameren Corporation | $ | 302 | $ | 374 | $ | 252 | $ | 182 | |||||||||
Average common shares outstanding - basic | 242.6 | 242.6 | 242.6 | 242.6 | |||||||||||||
Assumed settlement of performance share units | 2.5 | 0.3 | 1.8 | 0.3 | |||||||||||||
Average common shares outstanding - diluted | 245.1 | 242.9 | 244.4 | 242.9 | |||||||||||||
Earnings (loss) per common share – basic: | |||||||||||||||||
Continuing operations | $ | 1.26 | $ | 1.28 | $ | 1.92 | $ | 2.09 | |||||||||
Discontinued operations | (0.01 | ) | 0.26 | (0.88 | ) | (1.34 | ) | ||||||||||
Earnings (loss) per common share – basic | $ | 1.25 | $ | 1.54 | $ | 1.04 | $ | 0.75 | |||||||||
Earnings (loss) per common share – diluted: | |||||||||||||||||
Continuing operations | $ | 1.25 | $ | 1.28 | $ | 1.91 | $ | 2.09 | |||||||||
Discontinued operations | (0.01 | ) | 0.26 | (0.88 | ) | (1.34 | ) | ||||||||||
Earnings (loss) per common share – diluted | $ | 1.24 | $ | 1.54 | $ | 1.03 | $ | 0.75 | |||||||||
Average performance share units excluded from calculation(a) | — | 1 | 0.1 | 1 | |||||||||||||
(a) | Weighted-average number of performance share units that were excluded from the “Assumed settlement of performance share units” provided above because the performance or market conditions related to the awards had not yet been met. | ||||||||||||||||
Summary Of Nonvested Shares Related To Long-Term Incentive Plan | ' | ||||||||||||||||
A summary of nonvested performance share units at September 30, 2013, and changes during the nine months ended September 30, 2013, under the 2006 Omnibus Incentive Compensation Plan (2006 Plan) are presented below: | |||||||||||||||||
Performance Share Units | |||||||||||||||||
Share Units | Weighted-average Fair Value Per Unit at Grant Date | ||||||||||||||||
Nonvested as of January 1, 2013 | 1,192,487 | $ | 33.56 | ||||||||||||||
Granted(a) | 837,199 | 31.19 | |||||||||||||||
Forfeitures | (7,757 | ) | 32.66 | ||||||||||||||
Vested(b) | (131,960 | ) | 31.3 | ||||||||||||||
Nonvested as of September 30, 2013 | 1,889,969 | $ | 32.67 | ||||||||||||||
(a) | Includes performance share units (share units) granted to certain executive and nonexecutive officers and other eligible employees in 2013 under the 2006 Plan. | ||||||||||||||||
(b) | Share units vested due to the attainment of retirement eligibility by certain employees. Actual shares issued for retirement-eligible employees will vary depending on actual performance over the three-year measurement period. | ||||||||||||||||
Schedule Of Amortization Expense Based On Usage Of Renewable Energy Credits And Emission Allowances | ' | ||||||||||||||||
The following table presents amortization expense based on usage of renewable energy credits and emission allowances, net of gains from sales, for Ameren, Ameren Missouri, and Ameren Illinois, during the three and nine months ended September 30, 2013, and 2012. | |||||||||||||||||
Three Months | Nine Months | ||||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||||
Ameren Missouri | $ | — | $ | 1 | $ | (a) | $ | 1 | |||||||||
Ameren Illinois | 2 | 1 | 9 | 1 | |||||||||||||
Ameren | $ | 2 | $ | 2 | $ | 9 | $ | 2 | |||||||||
(a) | Less than $1 million. | ||||||||||||||||
Schedule of Excise Taxes | ' | ||||||||||||||||
The following table presents excise taxes recorded in “Operating Revenues - Electric,” “Operating Revenues - Gas” and “Operating Expenses - Taxes other than income taxes” for the three and nine months ended September 30, 2013, and 2012: | |||||||||||||||||
Three Months | Nine Months | ||||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||||
Ameren Missouri | $ | 49 | $ | 46 | $ | 120 | $ | 111 | |||||||||
Ameren Illinois | 10 | 9 | 43 | 37 | |||||||||||||
Ameren | $ | 59 | $ | 55 | $ | 163 | $ | 148 | |||||||||
Schedule of Asset Retirement Obligations | ' | ||||||||||||||||
The following table provides a reconciliation of the beginning balance and ending carrying amount of AROs for the nine months ended September 30, 2013: | |||||||||||||||||
Ameren | Ameren | Other(c) | Ameren(a) | ||||||||||||||
Missouri(a) | Illinois(b) | ||||||||||||||||
Balance at December 31, 2012 | $ | 346 | $ | 3 | $ | 26 | $ | 375 | |||||||||
Liabilities incurred | — | — | — | — | |||||||||||||
Liabilities settled | (d) | (d) | (d) | (d) | |||||||||||||
Accretion in 2013(e) | 14 | (d) | 1 | 15 | |||||||||||||
Change in estimates(f) | 2 | (d) | (d) | 2 | |||||||||||||
Balance at September 30, 2013 | $ | 362 | $ | 3 | $ | 27 | $ | 392 | |||||||||
(a) | The nuclear decommissioning trust fund assets of $459 million and $408 million as of September 30, 2013, and December 31, 2012, respectively, were restricted for decommissioning of the Callaway energy center. | ||||||||||||||||
(b) | Balance included in “Other deferred credits and liabilities” on the balance sheet. | ||||||||||||||||
(c) | Represents amounts for the Meredosia and Hutsonville energy centers. Pursuant to the transaction agreement to divest New AER to IPH, Ameren will retain the AROs associated with the Meredosia and Hutsonville energy centers. See Note 2 - Divestiture Transactions and Discontinued Operations for additional information. | ||||||||||||||||
(d) | Less than $1 million. | ||||||||||||||||
(e) | Accretion was recorded as an increase to regulatory assets at Ameren Missouri and Ameren Illinois. | ||||||||||||||||
(f) | Ameren Missouri changed its fair value estimates for asbestos removal and certain CCR storage facilities. | ||||||||||||||||
Equity Changes Attributable To Noncontrolling Interest | ' | ||||||||||||||||
A reconciliation of the equity changes attributable to the noncontrolling interests at Ameren for the three and nine months ended September 30, 2013, and 2012, is shown below: | |||||||||||||||||
Three Months | Nine Months | ||||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||||
Noncontrolling interests, beginning of period (a) | $ | 151 | $ | 145 | $ | 151 | $ | 149 | |||||||||
Net income from continuing operations attributable to noncontrolling interests | 2 | 2 | 5 | 5 | |||||||||||||
Net loss from discontinued operations attributable to noncontrolling interests | — | (2 | ) | — | (6 | ) | |||||||||||
Dividends paid to noncontrolling interest holders | (2 | ) | (2 | ) | (5 | ) | (5 | ) | |||||||||
Other comprehensive income attributable to noncontrolling interests(b) | — | 9 | — | 9 | |||||||||||||
Noncontrolling interests, end of period (a) | $ | 151 | $ | 152 | $ | 151 | $ | 152 | |||||||||
(a) | Includes the 20% EEI ownership interest not owned by Ameren. The assets and liabilities of EEI were consolidated in Ameren’s balance sheet at a 100% ownership level and were included in “Current assets of discontinued operations” and “Current liabilities of discontinued operations.” The 20% ownership interest not owned by Ameren was included in “Noncontrolling interests” on Ameren’s September 30, 2013, and December 31, 2012 balance sheets. See Note 2 - Divestiture Transactions and Discontinued Operations for additional information. | ||||||||||||||||
(b) | Represents the noncontrolling interest of EEI’s pension and other postretirement benefit plan activity, net of income taxes of $-, $6, $-, and $6, respectively. |
Divestiture_Transactions_and_D1
Divestiture Transactions and Discontinued Operations (Tables) | 9 Months Ended | ||||||||||||||||
Sep. 30, 2013 | |||||||||||||||||
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | ' | ||||||||||||||||
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures | ' | ||||||||||||||||
The following table presents the carrying amounts of the components of assets and liabilities segregated on Ameren's consolidated balance sheets as discontinued operations at September 30, 2013, and December 31, 2012: | |||||||||||||||||
30-Sep-13 | 31-Dec-12 | ||||||||||||||||
Assets of discontinued operations | |||||||||||||||||
Cash and cash equivalents | $ | 25 | $ | 25 | |||||||||||||
Accounts receivable and unbilled revenue | 102 | 102 | |||||||||||||||
Materials and supplies | 121 | 134 | |||||||||||||||
Mark-to-market derivative assets | 71 | 102 | |||||||||||||||
Property and plant, net | 623 | 748 | |||||||||||||||
Accumulated deferred income taxes, net | 357 | 385 | |||||||||||||||
Other assets | 96 | 104 | |||||||||||||||
Total assets of discontinued operations | $ | 1,395 | $ | 1,600 | |||||||||||||
Liabilities of discontinued operations | |||||||||||||||||
Accounts payable and other current obligations | $ | 141 | $ | 133 | |||||||||||||
Mark-to-market derivative liabilities | 38 | 63 | |||||||||||||||
Long-term debt, net | 824 | 824 | |||||||||||||||
Asset retirement obligations | 87 | 78 | |||||||||||||||
Pension and other postretirement benefits | 32 | 40 | |||||||||||||||
Other liabilities | 19 | 28 | |||||||||||||||
Total liabilities of discontinued operations | $ | 1,141 | $ | 1,166 | |||||||||||||
Accumulated other comprehensive income(a) | $ | 3 | $ | 19 | |||||||||||||
Noncontrolling interest(b) | $ | 8 | $ | 8 | |||||||||||||
(a) | Accumulated other comprehensive income related to discontinued operations remains in “Accumulated other comprehensive loss” on Ameren’s September 30, 2013, and December 31, 2012, balance sheets. This balance relates to New AER assets and liabilities that will be realized or removed from Ameren’s balance sheet either before or at the closing of the New AER divestiture. | ||||||||||||||||
(b) | The 20% ownership interest of EEI not owned by Ameren was included in “Noncontrolling interests” on Ameren’s September 30, 2013, and December 31, 2012, balance sheets. This noncontrolling interest will be removed from Ameren’s balance sheet at the closing of the New AER divestiture. | ||||||||||||||||
The following table presents the components of discontinued operations in Ameren's consolidated statement of income for the three and nine months ended September 30, 2013, and 2012: | |||||||||||||||||
Three Months | Nine months | ||||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||||
Operating revenues | $ | 311 | $ | 293 | $ | 878 | $ | 797 | |||||||||
Operating expenses | (309 | ) | (237 | ) | (1,034 | ) | (a) | (1,301 | ) | (b) | |||||||
Operating income (loss) | 2 | 56 | (156 | ) | (504 | ) | |||||||||||
Other income (loss) | — | — | (1 | ) | — | ||||||||||||
Interest charges | (9 | ) | (14 | ) | (31 | ) | (43 | ) | |||||||||
Income (loss) before income taxes | (7 | ) | 42 | (188 | ) | (547 | ) | ||||||||||
Income tax (expense) benefit | 4 | 21 | (24 | ) | 216 | ||||||||||||
Income (loss) from discontinued operations, net of taxes | $ | (3 | ) | $ | 63 | $ | (212 | ) | $ | (331 | ) | ||||||
(a) | Includes a noncash pretax impairment charge of $175 million for the nine months ended September 30, 2013, to reduce the carrying value of the New AER disposal group to its estimated fair value less cost to sell. | ||||||||||||||||
(b) | Includes a noncash pretax asset impairment charge of $628 million to reduce the carrying value of AERG’s Duck Creek energy center to its estimated fair value under held and used accounting guidance. | ||||||||||||||||
Schedule Of Coverage Ratios | ' | ||||||||||||||||
Ameren Missouri | |||||||||||||||||
In October 2013, $44 million of Ameren Missouri’s 1993 5.45% Series tax-exempt first mortgage bonds were redeemed at par plus accrued interest. In October 2013, $200 million of Ameren Missouri’s 4.65% senior secured notes matured and were retired. | |||||||||||||||||
Indenture Provisions and Other Covenants | |||||||||||||||||
Ameren Missouri’s and Ameren Illinois’ indentures and articles of incorporation include covenants and provisions related to issuances of first mortgage bonds and preferred stock. Ameren Missouri and Ameren Illinois are required to meet certain ratios to issue additional first mortgage bonds and preferred stock. A failure to achieve these ratios would not result in a default under these covenants and provisions, but would restrict the companies’ ability to issue bonds or preferred stock. The following table summarizes the required and actual interest coverage ratios for interest charges and dividend coverage ratios and bonds and preferred stock issuable as of September 30, 2013, at an assumed annual interest rate of 6% and dividend rate of 7%. | |||||||||||||||||
Required Interest | Actual Interest | Bonds Issuable(b) | Required Dividend | Actual Dividend | Preferred Stock | ||||||||||||
Coverage Ratio(a) | Coverage Ratio | Coverage Ratio(c) | Coverage Ratio | Issuable | |||||||||||||
Ameren Missouri | ≥2.0 | 4.3 | $ | 3,564 | ≥2.5 | 111.5 | $ | 2,130 | |||||||||
Ameren Illinois | ≥2.0 | 7.4 | 3,536 | (d) | ≥1.5 | 2.7 | 203 | ||||||||||
(a) | Coverage required on the annual interest charges on first mortgage bonds outstanding and to be issued. Coverage is not required in certain cases when additional first mortgage bonds are issued on the basis of retired bonds. | ||||||||||||||||
(b) | Amount of bonds issuable based either on required coverage ratios or unfunded property additions, whichever is more restrictive. The amounts shown also include bonds issuable based on retired bond capacity of $485 million and $645 million at Ameren Missouri and Ameren Illinois, respectively. | ||||||||||||||||
(c) | Coverage required on the annual dividend on preferred stock outstanding and to be issued, as required in the respective company’s articles of incorporation. | ||||||||||||||||
(d) | Amount of bonds issuable by Ameren Illinois based on unfunded property additions and retired bonds solely under the former IP mortgage indenture. | ||||||||||||||||
Ameren Energy Generating Company | ' | ||||||||||||||||
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | ' | ||||||||||||||||
Schedule Of Coverage Ratios | ' | ||||||||||||||||
Genco Indenture Provisions | |||||||||||||||||
Genco’s indenture includes provisions that require Genco to maintain certain interest coverage and debt-to-capital ratios in order for Genco to pay dividends, to make principal or interest payments on subordinated borrowings, to make loans to or investments in affiliates, or to incur additional external, third-party indebtedness. The following table summarizes these ratios for the 12 months ended and as of September 30, 2013: | |||||||||||||||||
Required | Actual | ||||||||||||||||
Ratio | Ratio | ||||||||||||||||
Interest coverage ratio- restricted payment (a) | ≥1.75 | 1.05 | |||||||||||||||
Interest coverage ratio- additional indebtedness (b) | ≥2.50 | 1.05 | |||||||||||||||
Debt-to-capital ratio- additional indebtedness (b) | ≤60% | 51 | % | ||||||||||||||
(a) | As of the date of the restricted payment, as defined, the minimum ratio must have been achieved for the most recently ended four fiscal quarters and projected by management to be achieved for each of the subsequent four six-month periods. Investments in the non-state-regulated subsidiary money pool and repayments of non-state-regulated subsidiary money pool borrowings are not subject to this incurrence test. | ||||||||||||||||
(b) | Ratios must be computed on a pro forma basis considering the additional indebtedness to be incurred and the related interest expense. Non-state-regulated subsidiary money pool borrowings are defined as permitted indebtedness and are not subject to these incurrence tests. Other borrowings from third-party external sources are included in the definition of indebtedness and are subject to these incurrence tests. |
LongTerm_Debt_And_Equity_Finan1
Long-Term Debt And Equity Financings (Tables) | 9 Months Ended | ||||||||||||||
Sep. 30, 2013 | |||||||||||||||
Long-Term Debt And Equity Financings [Abstract] | ' | ||||||||||||||
Schedule Of Coverage Ratios | ' | ||||||||||||||
Ameren Missouri | |||||||||||||||
In October 2013, $44 million of Ameren Missouri’s 1993 5.45% Series tax-exempt first mortgage bonds were redeemed at par plus accrued interest. In October 2013, $200 million of Ameren Missouri’s 4.65% senior secured notes matured and were retired. | |||||||||||||||
Indenture Provisions and Other Covenants | |||||||||||||||
Ameren Missouri’s and Ameren Illinois’ indentures and articles of incorporation include covenants and provisions related to issuances of first mortgage bonds and preferred stock. Ameren Missouri and Ameren Illinois are required to meet certain ratios to issue additional first mortgage bonds and preferred stock. A failure to achieve these ratios would not result in a default under these covenants and provisions, but would restrict the companies’ ability to issue bonds or preferred stock. The following table summarizes the required and actual interest coverage ratios for interest charges and dividend coverage ratios and bonds and preferred stock issuable as of September 30, 2013, at an assumed annual interest rate of 6% and dividend rate of 7%. | |||||||||||||||
Required Interest | Actual Interest | Bonds Issuable(b) | Required Dividend | Actual Dividend | Preferred Stock | ||||||||||
Coverage Ratio(a) | Coverage Ratio | Coverage Ratio(c) | Coverage Ratio | Issuable | |||||||||||
Ameren Missouri | ≥2.0 | 4.3 | $ | 3,564 | ≥2.5 | 111.5 | $ | 2,130 | |||||||
Ameren Illinois | ≥2.0 | 7.4 | 3,536 | (d) | ≥1.5 | 2.7 | 203 | ||||||||
(a) | Coverage required on the annual interest charges on first mortgage bonds outstanding and to be issued. Coverage is not required in certain cases when additional first mortgage bonds are issued on the basis of retired bonds. | ||||||||||||||
(b) | Amount of bonds issuable based either on required coverage ratios or unfunded property additions, whichever is more restrictive. The amounts shown also include bonds issuable based on retired bond capacity of $485 million and $645 million at Ameren Missouri and Ameren Illinois, respectively. | ||||||||||||||
(c) | Coverage required on the annual dividend on preferred stock outstanding and to be issued, as required in the respective company’s articles of incorporation. | ||||||||||||||
(d) | Amount of bonds issuable by Ameren Illinois based on unfunded property additions and retired bonds solely under the former IP mortgage indenture. |
Other_Income_and_Expenses_Tabl
Other Income and Expenses (Tables) | 9 Months Ended | ||||||||||||||||
Sep. 30, 2013 | |||||||||||||||||
Other Nonoperating Income (Expense) [Abstract] | ' | ||||||||||||||||
Other Income And Expenses | ' | ||||||||||||||||
The following table presents the components of “Other Income and Expenses” in the Ameren Companies’ statements of income for the three and nine months ended September 30, 2013, and 2012: | |||||||||||||||||
Three Months | Nine Months | ||||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||||
Ameren:(a) | |||||||||||||||||
Miscellaneous income: | |||||||||||||||||
Allowance for equity funds used during construction | $ | 10 | $ | 9 | $ | 26 | $ | 26 | |||||||||
Interest income on industrial development revenue bonds | 7 | 7 | 21 | 21 | |||||||||||||
Interest and dividend income | 2 | — | 3 | 4 | (b) | ||||||||||||
Other | 1 | 1 | 1 | 2 | |||||||||||||
Total miscellaneous income | $ | 20 | $ | 17 | $ | 51 | $ | 53 | |||||||||
Miscellaneous expense: | |||||||||||||||||
Donations | $ | 2 | $ | 3 | $ | 7 | $ | 18 | (c) | ||||||||
Other | 3 | 3 | 11 | 10 | |||||||||||||
Total miscellaneous expense | $ | 5 | $ | 6 | $ | 18 | $ | 28 | |||||||||
Ameren Missouri: | |||||||||||||||||
Miscellaneous income: | |||||||||||||||||
Allowance for equity funds used during construction | $ | 8 | $ | 8 | $ | 22 | $ | 23 | |||||||||
Interest income on industrial development revenue bonds | 7 | 7 | 21 | 21 | |||||||||||||
Interest and dividend income | 1 | — | 1 | 4 | (b) | ||||||||||||
Total miscellaneous income | $ | 16 | $ | 15 | $ | 44 | $ | 48 | |||||||||
Miscellaneous expense: | |||||||||||||||||
Donations | $ | — | $ | 2 | $ | 3 | $ | 7 | |||||||||
Other | 2 | 2 | 7 | 4 | |||||||||||||
Total miscellaneous expense | $ | 2 | $ | 4 | $ | 10 | $ | 11 | |||||||||
Ameren Illinois: | |||||||||||||||||
Miscellaneous income: | |||||||||||||||||
Allowance for equity funds used during construction | $ | 2 | $ | 1 | $ | 4 | $ | 3 | |||||||||
Interest and dividend income | 1 | — | 2 | — | |||||||||||||
Other | 1 | 1 | 1 | 2 | |||||||||||||
Total miscellaneous income | $ | 4 | $ | 2 | $ | 7 | $ | 5 | |||||||||
Miscellaneous expense: | |||||||||||||||||
Donations | $ | — | $ | 1 | $ | 3 | $ | 11 | (c) | ||||||||
Other | 3 | 1 | 4 | 4 | |||||||||||||
Total miscellaneous expense | $ | 3 | $ | 2 | $ | 7 | $ | 15 | |||||||||
(a) | Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations. | ||||||||||||||||
(b) | Includes interest income received in 2012 relating to a refund of charges included in an expired power purchase agreement with Entergy. | ||||||||||||||||
(c) | Includes Ameren Illinois’ one-time $7.5 million contribution to the Illinois Science and Energy Innovation Trust pursuant to the IEIMA as a result of Ameren Illinois’ 2012 election to participate in the formula ratemaking process. |
Derivative_Financial_Instrumen2
Derivative Financial Instruments (Tables) | 9 Months Ended | |||||||||||||||||||
Sep. 30, 2013 | ||||||||||||||||||||
Derivative Instruments and Hedging Activities Disclosure [Abstract] | ' | |||||||||||||||||||
Open Gross Derivative Volumes By Commodity Type | ' | |||||||||||||||||||
The following table presents open gross commodity contract volumes by commodity type as of September 30, 2013, and December 31, 2012: | ||||||||||||||||||||
Quantity (in millions, except as indicated) | ||||||||||||||||||||
Commodity | Accrual & NPNS | Other | Derivatives That Qualify | |||||||||||||||||
Contracts(a) | Derivatives(b) | for Regulatory Deferral(c) | ||||||||||||||||||
2013 | 2012 | 2013 | 2012 | 2013 | 2012 | |||||||||||||||
Coal (in tons) | ||||||||||||||||||||
Ameren Missouri & Ameren | 81 | 96 | (d) | (d) | (d) | (d) | ||||||||||||||
Fuel oils (in gallons)(e) | ||||||||||||||||||||
Ameren Missouri & Ameren | (d) | (d) | (d) | (d) | 60 | 70 | ||||||||||||||
Natural gas (in mmbtu) | ||||||||||||||||||||
Ameren Missouri | 2 | 4 | — | — | 29 | 19 | ||||||||||||||
Ameren Illinois | 6 | 16 | (d) | (d) | 115 | 128 | ||||||||||||||
Ameren | 8 | 20 | — | — | 144 | 147 | ||||||||||||||
Power (in megawatthours) | ||||||||||||||||||||
Ameren Missouri | 3 | 3 | 1 | 2 | 5 | 9 | ||||||||||||||
Ameren Illinois | 15 | 21 | (d) | (d) | 11 | 14 | ||||||||||||||
Ameren | 18 | 24 | 1 | 2 | 16 | 23 | ||||||||||||||
Renewable energy credits(f) | ||||||||||||||||||||
Ameren Missouri | 3 | 3 | (d) | (d) | (d) | (d) | ||||||||||||||
Ameren Illinois | 11 | 12 | (d) | (d) | (d) | (d) | ||||||||||||||
Ameren | 14 | 15 | (d) | (d) | (d) | (d) | ||||||||||||||
Uranium (pounds in thousands) | ||||||||||||||||||||
Ameren Missouri & Ameren | 4,516 | 5,142 | (d) | (d) | 996 | 446 | ||||||||||||||
(a) | Accrual contracts include commodity contracts that do not qualify as derivatives. As of September 30, 2013, these contracts ran through December 2017, March 2015, September 2024, May 2032, and October 2024 for coal, natural gas, power, renewable energy credits, and uranium, respectively. | |||||||||||||||||||
(b) | As of September 30, 2013, these contracts ran through December 2014 for power. | |||||||||||||||||||
(c) | As of September 30, 2013, these contracts ran through October 2015, October 2019, May 2032, and October 2016 for fuel oils, natural gas, power, and uranium, respectively. | |||||||||||||||||||
(d) | Not applicable. | |||||||||||||||||||
(e) | Fuel oils consist of heating oil, ultra-low sulfur diesel, and crude oil. | |||||||||||||||||||
(f) | A renewable energy credit is created for every one megawatthour of renewable energy generated. The Ameren Companies’ contracts include renewable energy credits from solar and wind-generated power. | |||||||||||||||||||
Derivative Instruments Carrying Value | ' | |||||||||||||||||||
The following table presents the carrying value and balance sheet location of all derivative instruments as of September 30, 2013, and December 31, 2012: | ||||||||||||||||||||
Balance Sheet Location | Ameren | Ameren Missouri | Ameren Illinois | |||||||||||||||||
2013 | ||||||||||||||||||||
Derivative assets not designated as hedging instruments(a) | ||||||||||||||||||||
Commodity contracts: | ||||||||||||||||||||
Fuel oils | Other current assets | $ | 6 | $ | 6 | $ | — | |||||||||||||
Other assets | 2 | 2 | — | |||||||||||||||||
Natural gas | Other current assets | 1 | 1 | — | ||||||||||||||||
Power | Other current assets | 30 | 30 | — | ||||||||||||||||
Other assets | 1 | 1 | — | |||||||||||||||||
Uranium | Other current assets | 1 | 1 | — | ||||||||||||||||
Total assets | $ | 41 | $ | 41 | $ | — | ||||||||||||||
Derivative liabilities not designated as hedging instruments(a) | ||||||||||||||||||||
Commodity contracts: | ||||||||||||||||||||
Fuel oils | MTM derivative liabilities | $ | 3 | $ | (b) | $ | — | |||||||||||||
Other current liabilities | — | 3 | — | |||||||||||||||||
Other deferred credits and liabilities | 1 | 1 | — | |||||||||||||||||
Natural gas | MTM derivative liabilities | 45 | (b) | 38 | ||||||||||||||||
Other current liabilities | — | 7 | — | |||||||||||||||||
Other deferred credits and liabilities | 30 | 6 | 24 | |||||||||||||||||
Power | MTM derivative liabilities | 13 | (b) | 10 | ||||||||||||||||
Other current liabilities | — | 3 | — | |||||||||||||||||
Other deferred credits and liabilities | 84 | — | 84 | |||||||||||||||||
Uranium | MTM derivative liabilities | 4 | (b) | — | ||||||||||||||||
Other current liabilities | — | 4 | — | |||||||||||||||||
Other deferred credits and liabilities | 2 | 2 | — | |||||||||||||||||
Total liabilities | $ | 182 | $ | 26 | $ | 156 | ||||||||||||||
2012 | ||||||||||||||||||||
Derivative assets not designated as hedging instruments(a) | ||||||||||||||||||||
Commodity contracts: | ||||||||||||||||||||
Fuel oils | Other current assets | $ | 8 | $ | 8 | $ | — | |||||||||||||
Other assets | 4 | 4 | — | |||||||||||||||||
Natural gas | Other current assets | 1 | — | 1 | ||||||||||||||||
Other assets | 1 | 1 | — | |||||||||||||||||
Power | Other current assets | 14 | 14 | — | ||||||||||||||||
Other assets | 1 | 1 | — | |||||||||||||||||
Total assets | $ | 29 | $ | 28 | $ | 1 | ||||||||||||||
Derivative liabilities not designated as hedging instruments(a) | ||||||||||||||||||||
Commodity contracts: | ||||||||||||||||||||
Fuel oils | MTM derivative liabilities | $ | 2 | $ | (b) | $ | — | |||||||||||||
Other current liabilities | — | 2 | — | |||||||||||||||||
Other deferred credits and liabilities | 2 | 2 | — | |||||||||||||||||
Natural gas | MTM derivative liabilities | 64 | (b) | 56 | ||||||||||||||||
Other current liabilities | — | 8 | — | |||||||||||||||||
Other deferred credits and liabilities | 45 | 7 | 38 | |||||||||||||||||
Power | MTM derivative liabilities | 25 | (b) | 21 | ||||||||||||||||
Other current liabilities | — | 4 | — | |||||||||||||||||
Other deferred credits and liabilities | 90 | — | 90 | |||||||||||||||||
Uranium | MTM derivative liabilities | 1 | (b) | — | ||||||||||||||||
Other current liabilities | — | 1 | — | |||||||||||||||||
Other deferred credits and liabilities | 1 | 1 | — | |||||||||||||||||
Total liabilities | $ | 230 | $ | 25 | $ | 205 | ||||||||||||||
(a) | Includes derivatives subject to regulatory deferral. | |||||||||||||||||||
(b) | Balance sheet line item not applicable to registrant. | |||||||||||||||||||
Cumulative Pretax Net Gains (Losses) On All Derivative Instruments In OCI | ' | |||||||||||||||||||
The following table presents the cumulative amount of pretax net gains (losses) on all derivative instruments deferred in regulatory assets or regulatory liabilities as of September 30, 2013, and December 31, 2012: | ||||||||||||||||||||
Ameren | Ameren | Ameren | ||||||||||||||||||
Missouri | Illinois | |||||||||||||||||||
2013 | ||||||||||||||||||||
Cumulative gains (losses) deferred in regulatory liabilities or assets: | ||||||||||||||||||||
Fuel oils derivative contracts(a) | $ | 1 | $ | 1 | $ | — | ||||||||||||||
Natural gas derivative contracts(b) | (74 | ) | (12 | ) | (62 | ) | ||||||||||||||
Power derivative contracts(c) | (67 | ) | 27 | (94 | ) | |||||||||||||||
Uranium derivative contracts(d) | (5 | ) | (5 | ) | — | |||||||||||||||
2012 | ||||||||||||||||||||
Cumulative gains (losses) deferred in regulatory liabilities or assets: | ||||||||||||||||||||
Fuel oils derivative contracts(a) | $ | 4 | $ | 4 | $ | — | ||||||||||||||
Natural gas derivative contracts(b) | (107 | ) | (14 | ) | (93 | ) | ||||||||||||||
Power derivative contracts(c) | (99 | ) | 12 | (111 | ) | |||||||||||||||
Uranium derivative contracts(d) | (2 | ) | (2 | ) | — | |||||||||||||||
(a) | Represents net gains (losses) on fuel oils derivative contracts at Ameren Missouri. These contracts are a partial hedge of Ameren Missouri’s transportation costs for coal through October 2015 as of September 30, 2013. Current gains deferred as regulatory liabilities include $3 million and $3 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. Current losses deferred as regulatory assets include $1 million and $1 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. | |||||||||||||||||||
(b) | Represents net losses associated with natural gas derivative contracts. These contracts are a partial hedge of natural gas requirements through October 2019 at Ameren and Ameren Missouri and through March 2017 at Ameren Illinois as of September 30, 2013. Current gains deferred as regulatory liabilities include $1 million, and $1 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. Current losses deferred as regulatory assets include $45 million, $7 million, and $38 million at Ameren, Ameren Missouri and Ameren Illinois, respectively, as of September 30, 2013. | |||||||||||||||||||
(c) | Represents net gains (losses) associated with power derivative contracts. These contracts are a partial hedge of power price requirements through May 2032 at Ameren and Ameren Illinois and through December 2015 at Ameren Missouri as of September 30, 2013. Current gains deferred as regulatory liabilities include $29 million and $29 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. Current losses deferred as regulatory assets include $13 million, $3 million, and $10 million at Ameren, Ameren Missouri and Ameren Illinois, respectively, as of September 30, 2013. | |||||||||||||||||||
(d) | Represents net losses on uranium derivative contracts at Ameren Missouri. These contracts are a partial hedge of Ameren Missouri’s uranium requirements through October 2016 as of September 30, 2013. Current gains deferred as regulatory liabilities included $1 million and $1 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. Current losses deferred as regulatory assets include $4 million and $4 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. | |||||||||||||||||||
Offsetting Derivative Assets and Liabilities | ' | |||||||||||||||||||
The following table provides the recognized gross derivative balances and the net amounts of those derivatives subject to an enforceable master netting arrangement or similar agreement as of September 30, 2013, and December 31, 2012: | ||||||||||||||||||||
Gross Amounts Not Offset in the Balance Sheet | ||||||||||||||||||||
Gross Amounts Recognized in the Balance Sheet | Derivative Instruments | Cash Collateral Received/Posted(a) | Net | |||||||||||||||||
Amount | ||||||||||||||||||||
2013 | ||||||||||||||||||||
Commodity contracts eligible to be offset: | ||||||||||||||||||||
Assets: | ||||||||||||||||||||
Ameren | $ | 41 | $ | 11 | $ | — | $ | 30 | ||||||||||||
Ameren Missouri | 41 | 11 | — | 30 | ||||||||||||||||
Ameren Illinois | — | — | — | — | ||||||||||||||||
Liabilities: | ||||||||||||||||||||
Ameren | $ | 182 | $ | 11 | $ | 32 | $ | 139 | ||||||||||||
Ameren Missouri | 26 | 11 | 8 | 7 | ||||||||||||||||
Ameren Illinois | 156 | — | 24 | 132 | ||||||||||||||||
2012 | ||||||||||||||||||||
Commodity contracts eligible to be offset: | ||||||||||||||||||||
Assets: | ||||||||||||||||||||
Ameren | $ | 29 | $ | 10 | $ | — | $ | 19 | ||||||||||||
Ameren Missouri | 28 | 9 | — | 19 | ||||||||||||||||
Ameren Illinois | 1 | 1 | — | — | ||||||||||||||||
Liabilities: | ||||||||||||||||||||
Ameren | $ | 230 | $ | 10 | $ | 65 | $ | 155 | ||||||||||||
Ameren Missouri | 25 | 9 | 7 | 9 | ||||||||||||||||
Ameren Illinois | 205 | 1 | 58 | 146 | ||||||||||||||||
(a) | Cash collateral received reduces gross asset balances and is included in “Other current liabilities” and “Other deferred credits and liabilities” on the balance sheet. Cash collateral posted reduces gross liability balances and is included in “Other current assets” and “Other assets” on the balance sheet. | |||||||||||||||||||
Maximum Exposure If Counterparties Fail To Perform On Contracts | ' | |||||||||||||||||||
The maximum exposure is based on the gross fair value of financial instruments, including accrual and NPNS contracts, which excludes collateral held, and does not consider the legally binding right to net transactions based on master trading and netting agreements. | ||||||||||||||||||||
Commodity | Electric | Financial | Municipalities/ | Total | ||||||||||||||||
Marketing | Utilities | Companies | Cooperatives | |||||||||||||||||
Companies | ||||||||||||||||||||
2013 | ||||||||||||||||||||
Ameren Missouri | $ | 1 | $ | 1 | $ | 7 | $ | 2 | $ | 11 | ||||||||||
Ameren Illinois | — | — | — | — | — | |||||||||||||||
Ameren | $ | 1 | $ | 1 | $ | 7 | $ | 2 | $ | 11 | ||||||||||
2012 | ||||||||||||||||||||
Ameren Missouri | $ | 2 | $ | 3 | $ | 14 | $ | 3 | $ | 22 | ||||||||||
Ameren Illinois | — | — | 1 | — | 1 | |||||||||||||||
Ameren | $ | 2 | $ | 3 | $ | 15 | $ | 3 | $ | 23 | ||||||||||
Potential Loss On Counterparty Exposures | ' | |||||||||||||||||||
The following table presents the potential loss after consideration of collateral and application of master trading and netting agreements as of September 30, 2013, and December 31, 2012: | ||||||||||||||||||||
Commodity | Electric | Financial | Municipalities/ | Total | ||||||||||||||||
Marketing | Utilities | Companies | Cooperatives | |||||||||||||||||
Companies | ||||||||||||||||||||
2013 | ||||||||||||||||||||
Ameren Missouri | $ | 1 | $ | — | $ | 2 | $ | 2 | $ | 5 | ||||||||||
Ameren Illinois | — | — | — | — | — | |||||||||||||||
Ameren | $ | 1 | $ | — | $ | 2 | $ | 2 | $ | 5 | ||||||||||
2012 | ||||||||||||||||||||
Ameren Missouri | $ | 1 | $ | 1 | $ | 10 | $ | 3 | $ | 15 | ||||||||||
Ameren Illinois | — | — | — | — | — | |||||||||||||||
Ameren | $ | 1 | $ | 1 | $ | 10 | $ | 3 | $ | 15 | ||||||||||
Derivative Instruments With Credit Risk-Related Contingent Features | ' | |||||||||||||||||||
The additional collateral required is the net liability position allowed under the master trading and netting agreements, assuming (1) the credit risk-related contingent features underlying these agreements were triggered on September 30, 2013, or December 31, 2012, respectively, and (2) those counterparties with rights to do so requested collateral: | ||||||||||||||||||||
Aggregate Fair Value of | Cash | Potential Aggregate Amount of | ||||||||||||||||||
Derivative Liabilities(a) | Collateral Posted | Additional Collateral Required(b) | ||||||||||||||||||
2013 | ||||||||||||||||||||
Ameren Missouri | $ | 69 | $ | 1 | $ | 63 | ||||||||||||||
Ameren Illinois | 101 | 24 | 70 | |||||||||||||||||
Ameren | $ | 170 | $ | 25 | $ | 133 | ||||||||||||||
2012 | ||||||||||||||||||||
Ameren Missouri | $ | 78 | $ | 3 | $ | 71 | ||||||||||||||
Ameren Illinois | 148 | 58 | 84 | |||||||||||||||||
Ameren | $ | 226 | $ | 61 | $ | 155 | ||||||||||||||
(a) | Prior to consideration of master trading and netting agreements and including NPNS contract exposures. | |||||||||||||||||||
(b) | As collateral requirements with certain counterparties are based on master trading and netting agreements, the aggregate amount of additional collateral required to be posted is determined after consideration of the netting effects of such agreements. | |||||||||||||||||||
Derivatives That Qualify For Regulatory Deferral | ' | |||||||||||||||||||
The following table represents the net change in market value for derivatives that qualify for regulatory deferral for the three and nine months ended September 30, 2013, and 2012: | ||||||||||||||||||||
Gain (Loss) Recognized in Regulatory Liabilities or Regulatory Assets | ||||||||||||||||||||
Three Months | Nine Months | |||||||||||||||||||
2013 | 2012 | 2013 | 2012 | |||||||||||||||||
Ameren | Fuel oils | $ | 1 | $ | 5 | $ | (3 | ) | $ | (9 | ) | |||||||||
Natural gas | 9 | 46 | 33 | 74 | ||||||||||||||||
Power(a) | (24 | ) | (6 | ) | 32 | (169 | ) | |||||||||||||
Uranium | (2 | ) | (1 | ) | (3 | ) | (1 | ) | ||||||||||||
Total | $ | (16 | ) | $ | 44 | $ | 59 | $ | (105 | ) | ||||||||||
Ameren Missouri | Fuel oils | $ | 1 | $ | 5 | $ | (3 | ) | $ | (9 | ) | |||||||||
Natural gas | — | 6 | 2 | 9 | ||||||||||||||||
Power | (10 | ) | (6 | ) | 15 | (3 | ) | |||||||||||||
Uranium | (2 | ) | (1 | ) | (3 | ) | (1 | ) | ||||||||||||
Total | $ | (11 | ) | $ | 4 | $ | 11 | $ | (4 | ) | ||||||||||
Ameren Illinois | Natural gas | $ | 9 | $ | 40 | $ | 31 | $ | 65 | |||||||||||
Power | (14 | ) | 56 | 17 | (25 | ) | ||||||||||||||
Total | $ | (5 | ) | $ | 96 | $ | 48 | $ | 40 | |||||||||||
(a) | Amounts include intercompany eliminations. |
Fair_Value_Measurements_Tables
Fair Value Measurements (Tables) | 9 Months Ended | |||||||||||||||||
Sep. 30, 2013 | ||||||||||||||||||
Fair Value Disclosures [Abstract] | ' | |||||||||||||||||
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis, Valuation Techniques | ' | |||||||||||||||||
The following table describes the valuation techniques and unobservable inputs for the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy as of September 30, 2013: | ||||||||||||||||||
Fair Value | Weighted | |||||||||||||||||
Assets | Liabilities | Valuation Technique | Unobservable Input | Range | Average | |||||||||||||
Level 3 Derivative asset and liability - commodity contracts(a): | ||||||||||||||||||
Ameren | Fuel oils | $ | 7 | $ | (4 | ) | Option model | Volatilities(%)(b) | 20-Sep | 17 | ||||||||
Discounted cash flow | Counterparty credit risk(%)(c)(d) | .26 - 3 | 2 | |||||||||||||||
Natural gas | 1 | (1 | ) | Option model | Volatilities(%)(b) | 29-May | 24 | |||||||||||
Nodal basis($/mmbtu)(c) | (0.40) - (0.20) | -0.4 | ||||||||||||||||
Discounted cash flow | Nodal basis($/mmbtu)(c) | -0.1 | (e) | |||||||||||||||
Counterparty credit risk(%)(c)(d) | 0.64 - 0.83 | 0.77 | ||||||||||||||||
Ameren credit risk(%)(c)(d) | 3-Feb | 2 | ||||||||||||||||
Power(f) | 29 | (95 | ) | Discounted cash flow | Average forward peak and off-peak power pricing - forwards/swaps($/MWh)(c) | 27 - 43 | 30 | |||||||||||
Estimated auction price for FTRs($/MW)(b) | (103) - 1790 | 660 | ||||||||||||||||
Nodal basis($/MWh)(c) | (5) - (1) | -3 | ||||||||||||||||
Counterparty credit risk(%)(c)(d) | 0.22 - 3 | 0.73 | ||||||||||||||||
Ameren credit risk(%)(c)(d) | 3 | (e) | ||||||||||||||||
Fundamental energy production model | Estimated future gas prices($/mmbtu)(b) | 7-Apr | 5 | |||||||||||||||
Escalation rate(%)(b)(g) | 5-Apr | 4 | ||||||||||||||||
Contract price allocation | Estimated renewable energy credit costs($/credit)(b) | 7-May | 6 | |||||||||||||||
Uranium | 1 | (6 | ) | Discounted cash flow | Average forward uranium pricing($/pound)(b) | 35 - 43 | 36 | |||||||||||
Ameren Missouri | Fuel oils | $ | 7 | $ | (4 | ) | Option model | Volatilities(%)(b) | 20-Sep | 17 | ||||||||
Discounted cash flow | Counterparty credit risk(%)(c)(d) | .26 - 3 | 2 | |||||||||||||||
Natural gas | 1 | (1 | ) | Option model | Volatilities(%)(b) | 29-May | 24 | |||||||||||
Nodal basis($/mmbtu)(c) | (0.40) - (0.20) | -0.4 | ||||||||||||||||
Discounted cash flow | Nodal basis($/mmbtu)(c) | -0.1 | (e) | |||||||||||||||
Counterparty credit risk(%)(c)(d) | 0.64 - 0.83 | 0.77 | ||||||||||||||||
Ameren Missouri credit risk(%)(c)(d) | 3-Feb | 2 | ||||||||||||||||
Power(f) | 29 | (1 | ) | Discounted cash flow | Average forward peak and off-peak power pricing - forwards/swaps($/MWh)(c) | 27 - 43 | 33 | |||||||||||
Estimated auction price for FTRs($/MW)(b) | (103) - 1790 | 660 | ||||||||||||||||
Nodal basis($/MWh)(c) | (4) - (1) | -4 | ||||||||||||||||
Counterparty credit risk(%)(c)(d) | 0.22 - 3 | 0.73 | ||||||||||||||||
Ameren Missouri credit risk(%)(c)(d) | 3 | (e) | ||||||||||||||||
Uranium | 1 | (6 | ) | Discounted cash flow | Average forward uranium pricing($/pound)(b) | 35 - 43 | 36 | |||||||||||
Ameren Illinois | Power(f) | $ | — | $ | (94 | ) | Discounted cash flow | Average forward peak and off-peak power pricing - forwards/swaps($/MWh)(b) | 27 - 37 | 30 | ||||||||
Nodal basis($/MWh)(b) | (5) - (1) | -3 | ||||||||||||||||
Ameren Illinois credit risk(%)(c)(d) | 3 | (e) | ||||||||||||||||
Fundamental energy production model | Estimated future gas prices($/mmbtu)(b) | 7-Apr | 5 | |||||||||||||||
Escalation rate(%)(b)(g) | 5-Apr | 4 | ||||||||||||||||
Contract price allocation | Estimated renewable energy credit costs($/credit)(b) | 7-May | 6 | |||||||||||||||
(a) | The derivative asset and liability balances are presented net of counterparty credit considerations. | |||||||||||||||||
(b) | Generally, significant increases (decreases) in this input in isolation would result in a significantly higher (lower) fair value measurement. | |||||||||||||||||
(c) | Generally, significant increases (decreases) in this input in isolation would result in a significantly lower (higher) fair value measurement. | |||||||||||||||||
(d) | Counterparty credit risk is only applied to counterparties with derivative asset balances. Ameren, Ameren Missouri, and Ameren Illinois credit risk is only applied to counterparties with derivative liability balances. | |||||||||||||||||
(e) | Not applicable. | |||||||||||||||||
(f) | Power valuations utilize visible third-party pricing evaluated by month for peak and off-peak demand through 2017. Valuations beyond 2017 utilize fundamentally modeled pricing by month for peak and off-peak demand. | |||||||||||||||||
(g) | Escalation rate applies to power prices 2026 and beyond. | |||||||||||||||||
The following table describes the valuation techniques and unobservable inputs for the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy as of December 31, 2012: | ||||||||||||||||||
Fair Value | Weighted | |||||||||||||||||
Assets | Liabilities | Valuation Technique | Unobservable Input | Range | Average | |||||||||||||
Level 3 Derivative asset and liability - commodity contracts(a): | ||||||||||||||||||
Ameren | Fuel oils | $ | 8 | $ | (3 | ) | Discounted cash flow | Escalation rate(%)(b) | .21 - .60 | 0.44 | ||||||||
Counterparty credit risk(%)(c)(d) | .12 - 1 | 1 | ||||||||||||||||
Ameren credit risk(%)(c)(d) | 2 | (e) | ||||||||||||||||
Option model | Volatilities(%)(b) | 27-Jul | 24 | |||||||||||||||
Power(f) | 14 | (114 | ) | Discounted cash flow | Average forward peak and off-peak power pricing - forwards/swaps($/MWh)(c) | 22 - 47 | 31 | |||||||||||
Estimated auction price for FTRs($/MW)(b) | (281) - 1,851 | 178 | ||||||||||||||||
Nodal basis($/MWh)(c) | (5) - (1) | -3 | ||||||||||||||||
Counterparty credit risk(%)(c)(d) | .22 - 1 | 1 | ||||||||||||||||
Ameren credit risk(%)(c)(d) | 5-Feb | 5 | ||||||||||||||||
Fundamental energy production model | Estimated future gas prices($/mmbtu)(b) | 8-Apr | 6 | |||||||||||||||
Contract price allocation | Estimated renewable energy credit costs($/credit)(b) | 7-May | 6 | |||||||||||||||
Uranium | — | (2 | ) | Discounted cash flow | Average forward uranium pricing($/pound)(b) | 43 - 46 | 44 | |||||||||||
Ameren Missouri | Fuel oils | $ | 8 | $ | (3 | ) | Discounted cash flow | Escalation rate(%)(b) | .21 - .60 | 0.44 | ||||||||
Counterparty credit risk(%)(c)(d) | .12 - 1 | 1 | ||||||||||||||||
Ameren Missouri credit risk(%)(c)(d) | 2 | (e) | ||||||||||||||||
Option model | Volatilities(%)(b) | 27-Jul | 24 | |||||||||||||||
Power(f) | 14 | (3 | ) | Discounted cash flow | Average forward peak and off-peak power pricing - forwards/swaps($/MWh)(c) | 24 - 56 | 36 | |||||||||||
Estimated auction price for FTRs($/MW)(b) | (281) - 1,851 | 178 | ||||||||||||||||
Nodal basis($/MWh)(c) | (5) - (1) | -2 | ||||||||||||||||
Counterparty credit risk(%)(c)(d) | .22 - 1 | 1 | ||||||||||||||||
Ameren Missouri credit risk(%)(c)(d) | 2 | (e) | ||||||||||||||||
Uranium | — | (2 | ) | Discounted cash flow | Average forward uranium pricing($/pound)(b) | 43 - 46 | 44 | |||||||||||
Ameren Illinois | Power(f) | $ | — | $ | (111 | ) | Discounted cash flow | Average forward peak and off-peak power pricing - forwards/swaps($/MWh)(b) | 22 - 47 | 30 | ||||||||
Nodal basis($/MWh)(b) | (5) - (1) | -3 | ||||||||||||||||
Ameren Illinois credit risk(%)(c)(d) | 5 | (e) | ||||||||||||||||
Fundamental energy production model | Estimated future gas prices($/mmbtu)(b) | 8-Apr | 6 | |||||||||||||||
Contract price allocation | Estimated renewable energy credit costs($/credit)(b) | 7-May | 6 | |||||||||||||||
(a) | The derivative asset and liability balances are presented net of counterparty credit considerations. | |||||||||||||||||
(b) | Generally, significant increases (decreases) in this input in isolation would result in a significantly higher (lower) fair value measurement. | |||||||||||||||||
(c) | Generally, significant increases (decreases) in this input in isolation would result in a significantly lower (higher) fair value measurement. | |||||||||||||||||
(d) | Counterparty credit risk is only applied to counterparties with derivative asset balances. Ameren, Ameren Missouri, and Ameren Illinois credit risk is only applied to counterparties with derivative liability balances. | |||||||||||||||||
(e) | Not applicable. | |||||||||||||||||
(f) | Power valuations utilize visible third-party pricing evaluated by month for peak and off-peak demand through 2017. Valuations beyond 2017 utilize fundamentally modeled pricing by month for peak and off-peak demand. | |||||||||||||||||
Schedule Of Fair Value Hierarchy Of Assets And Liabilities Measured At Fair Value On Recurring Basis | ' | |||||||||||||||||
The following table sets forth, by level within the fair value hierarchy, our assets and liabilities measured at fair value on a recurring basis as of September 30, 2013: | ||||||||||||||||||
Quoted Prices in | Significant Other | Significant Other | Total | |||||||||||||||
Active Markets for | Observable Inputs | Unobservable | ||||||||||||||||
Identical Assets | (Level 2) | Inputs | ||||||||||||||||
or Liabilities | (Level 3) | |||||||||||||||||
(Level 1) | ||||||||||||||||||
Assets: | ||||||||||||||||||
Ameren | Derivative assets - commodity contracts(a): | |||||||||||||||||
Fuel oils | $ | 1 | $ | — | $ | 7 | $ | 8 | ||||||||||
Natural gas | — | — | 1 | 1 | ||||||||||||||
Power | — | 2 | 29 | 31 | ||||||||||||||
Uranium | — | — | 1 | 1 | ||||||||||||||
Total derivative assets - commodity contracts | $ | 1 | $ | 2 | $ | 38 | $ | 41 | ||||||||||
Nuclear Decommissioning Trust Fund(b): | ||||||||||||||||||
Cash and cash equivalents | $ | 2 | $ | — | $ | — | $ | 2 | ||||||||||
Equity securities: | ||||||||||||||||||
U.S. large capitalization | 309 | — | — | 309 | ||||||||||||||
Debt securities: | ||||||||||||||||||
Corporate bonds | — | 45 | — | 45 | ||||||||||||||
Municipal bonds | — | 2 | — | 2 | ||||||||||||||
U.S. treasury and agency securities | — | 90 | — | 90 | ||||||||||||||
Asset-backed securities | — | 9 | — | 9 | ||||||||||||||
Other | — | 1 | — | 1 | ||||||||||||||
Total Nuclear Decommissioning Trust Fund | $ | 311 | $ | 147 | $ | — | $ | 458 | ||||||||||
Total Ameren | $ | 312 | $ | 149 | $ | 38 | $ | 499 | ||||||||||
Ameren | Derivative assets - commodity contracts(a): | |||||||||||||||||
Missouri | Fuel oils | $ | 1 | $ | — | $ | 7 | $ | 8 | |||||||||
Natural gas | — | — | 1 | 1 | ||||||||||||||
Power | — | 2 | 29 | 31 | ||||||||||||||
Uranium | — | — | 1 | 1 | ||||||||||||||
Total derivative assets - commodity contracts | $ | 1 | $ | 2 | $ | 38 | $ | 41 | ||||||||||
Nuclear Decommissioning Trust Fund(b): | ||||||||||||||||||
Cash and cash equivalents | $ | 2 | $ | — | $ | — | $ | 2 | ||||||||||
Equity securities: | ||||||||||||||||||
U.S. large capitalization | 309 | — | — | 309 | ||||||||||||||
Debt securities: | ||||||||||||||||||
Corporate bonds | — | 45 | — | 45 | ||||||||||||||
Municipal bonds | — | 2 | — | 2 | ||||||||||||||
U.S. treasury and agency securities | — | 90 | — | 90 | ||||||||||||||
Asset-backed securities | — | 9 | — | 9 | ||||||||||||||
Other | — | 1 | — | 1 | ||||||||||||||
Total Nuclear Decommissioning Trust Fund | $ | 311 | $ | 147 | $ | — | $ | 458 | ||||||||||
Total Ameren Missouri | $ | 312 | $ | 149 | $ | 38 | $ | 499 | ||||||||||
Liabilities: | ||||||||||||||||||
Ameren | Derivative liabilities - commodity contracts(a): | |||||||||||||||||
Fuel oils | $ | — | $ | — | $ | 4 | $ | 4 | ||||||||||
Natural gas | 5 | 69 | 1 | 75 | ||||||||||||||
Power | — | 2 | 95 | 97 | ||||||||||||||
Uranium | — | — | 6 | 6 | ||||||||||||||
Total Ameren | $ | 5 | $ | 71 | $ | 106 | $ | 182 | ||||||||||
Ameren | Derivative liabilities - commodity contracts(a): | |||||||||||||||||
Missouri | Fuel oils | $ | — | $ | — | $ | 4 | $ | 4 | |||||||||
Natural gas | 5 | 7 | 1 | 13 | ||||||||||||||
Power | — | 2 | 1 | 3 | ||||||||||||||
Uranium | — | — | 6 | 6 | ||||||||||||||
Total Ameren Missouri | $ | 5 | $ | 9 | $ | 12 | $ | 26 | ||||||||||
Ameren | Derivative liabilities - commodity contracts(a): | |||||||||||||||||
Illinois | Natural gas | $ | — | $ | 62 | $ | — | $ | 62 | |||||||||
Power | — | — | 94 | 94 | ||||||||||||||
Total Ameren Illinois | $ | — | $ | 62 | $ | 94 | $ | 156 | ||||||||||
(a) | The derivative asset and liability balances are presented net of counterparty credit considerations. | |||||||||||||||||
(b) | Balance excludes $1 million of receivables, payables, and accrued income, net. | |||||||||||||||||
The following table sets forth, by level within the fair value hierarchy, our assets and liabilities measured at fair value on a recurring basis as of December 31, 2012: | ||||||||||||||||||
Quoted Prices in | Significant Other | Significant Other | Total | |||||||||||||||
Active Markets for | Observable Inputs | Unobservable | ||||||||||||||||
Identical Assets | (Level 2) | Inputs | ||||||||||||||||
or Liabilities | (Level 3) | |||||||||||||||||
(Level 1) | ||||||||||||||||||
Assets: | ||||||||||||||||||
Ameren | Derivative assets - commodity contracts(a): | |||||||||||||||||
Fuel oils | $ | 4 | $ | — | $ | 8 | $ | 12 | ||||||||||
Natural gas | — | 2 | — | 2 | ||||||||||||||
Power | — | 1 | 14 | 15 | ||||||||||||||
Total derivative assets - commodity contracts | $ | 4 | $ | 3 | $ | 22 | $ | 29 | ||||||||||
Nuclear Decommissioning Trust Fund(b): | ||||||||||||||||||
Cash and cash equivalents | $ | 1 | $ | — | $ | — | $ | 1 | ||||||||||
Equity securities: | ||||||||||||||||||
U.S. large capitalization | 264 | — | — | 264 | ||||||||||||||
Debt securities: | ||||||||||||||||||
Corporate bonds | — | 47 | — | 47 | ||||||||||||||
Municipal bonds | — | 1 | — | 1 | ||||||||||||||
U.S. treasury and agency securities | — | 81 | — | 81 | ||||||||||||||
Asset-backed securities | — | 11 | — | 11 | ||||||||||||||
Other | — | 1 | — | 1 | ||||||||||||||
Total Nuclear Decommissioning Trust Fund | $ | 265 | $ | 141 | $ | — | $ | 406 | ||||||||||
Total Ameren | $ | 269 | $ | 144 | $ | 22 | $ | 435 | ||||||||||
Ameren | Derivative assets - commodity contracts(a): | |||||||||||||||||
Missouri | Fuel oils | $ | 4 | $ | — | $ | 8 | $ | 12 | |||||||||
Natural gas | — | 1 | — | 1 | ||||||||||||||
Power | — | 1 | 14 | 15 | ||||||||||||||
Total derivative assets - commodity contracts | $ | 4 | $ | 2 | $ | 22 | $ | 28 | ||||||||||
Nuclear Decommissioning Trust Fund(b): | ||||||||||||||||||
Cash and cash equivalents | $ | 1 | $ | — | $ | — | $ | 1 | ||||||||||
Equity securities: | ||||||||||||||||||
U.S. large capitalization | 264 | — | — | 264 | ||||||||||||||
Debt securities: | ||||||||||||||||||
Corporate bonds | — | 47 | — | 47 | ||||||||||||||
Municipal bonds | — | 1 | — | 1 | ||||||||||||||
U.S. treasury and agency securities | — | 81 | — | 81 | ||||||||||||||
Asset-backed securities | — | 11 | — | 11 | ||||||||||||||
Other | — | 1 | — | 1 | ||||||||||||||
Total Nuclear Decommissioning Trust Fund | $ | 265 | $ | 141 | $ | — | $ | 406 | ||||||||||
Total Ameren Missouri | $ | 269 | $ | 143 | $ | 22 | $ | 434 | ||||||||||
Ameren | Derivative assets - commodity contracts(a): | |||||||||||||||||
Illinois | Natural gas | $ | — | $ | 1 | $ | — | $ | 1 | |||||||||
Quoted Prices in | Significant Other | Significant Other | Total | |||||||||||||||
Active Markets for | Observable Inputs | Unobservable | ||||||||||||||||
Identical Assets | (Level 2) | Inputs | ||||||||||||||||
or Liabilities | (Level 3) | |||||||||||||||||
(Level 1) | ||||||||||||||||||
Liabilities: | ||||||||||||||||||
Ameren | Derivative liabilities - commodity contracts(a): | |||||||||||||||||
Fuel oils | $ | 1 | $ | — | $ | 3 | $ | 4 | ||||||||||
Natural gas | 7 | 102 | — | 109 | ||||||||||||||
Power | — | 1 | 114 | 115 | ||||||||||||||
Uranium | — | — | 2 | 2 | ||||||||||||||
Total Ameren | $ | 8 | $ | 103 | $ | 119 | $ | 230 | ||||||||||
Ameren | Derivative liabilities - commodity contracts(a): | |||||||||||||||||
Missouri | Fuel oils | $ | 1 | $ | — | $ | 3 | $ | 4 | |||||||||
Natural gas | 7 | 8 | — | 15 | ||||||||||||||
Power | — | 1 | 3 | 4 | ||||||||||||||
Uranium | — | — | 2 | 2 | ||||||||||||||
Total Ameren Missouri | $ | 8 | $ | 9 | $ | 8 | $ | 25 | ||||||||||
Ameren | Derivative liabilities - commodity contracts(a): | |||||||||||||||||
Illinois | Natural gas | $ | — | $ | 94 | $ | — | $ | 94 | |||||||||
Power | — | — | 111 | 111 | ||||||||||||||
Total Ameren Illinois | $ | — | $ | 94 | $ | 111 | $ | 205 | ||||||||||
(a) | The derivative asset and liability balances are presented net of counterparty credit considerations. | |||||||||||||||||
(b) | Balance excludes $2 million of receivables, payables, and accrued income, net. | |||||||||||||||||
Schedule Of Changes In The Fair Value Of Financial Assets And Liabilities Classified As Level Three In The Fair Value Hierarchy | ' | |||||||||||||||||
The following table summarizes the changes in the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy for the three months ended September 30, 2013: | ||||||||||||||||||
Net derivative commodity contracts | ||||||||||||||||||
Three Months | Ameren | Ameren | Ameren | |||||||||||||||
Missouri | Illinois | |||||||||||||||||
Fuel oils: | ||||||||||||||||||
Beginning balance at July 1, 2013 | $ | 3 | $ | (a) | $ | 3 | ||||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | 1 | (a) | 1 | |||||||||||||||
Total realized and unrealized gains (losses) | 1 | (a) | 1 | |||||||||||||||
Purchases | 1 | (a) | 1 | |||||||||||||||
Sales | (1 | ) | (a) | (1 | ) | |||||||||||||
Settlements | (1 | ) | (a) | (1 | ) | |||||||||||||
Ending balance at September 30, 2013 | $ | 3 | $ | (a) | $ | 3 | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | 1 | $ | (a) | $ | 1 | ||||||||||||
Natural gas: | ||||||||||||||||||
Beginning balance at July 1, 2013 | $ | (1 | ) | $ | 2 | $ | 1 | |||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | — | (2 | ) | (2 | ) | |||||||||||||
Total realized and unrealized gains (losses) | — | (2 | ) | (2 | ) | |||||||||||||
Purchases | 1 | — | 1 | |||||||||||||||
Ending balance at September 30, 2013 | $ | — | $ | — | $ | — | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | — | $ | (1 | ) | $ | (1 | ) | ||||||||||
Power: | ||||||||||||||||||
Beginning balance at July 1, 2013 | $ | 37 | $ | (80 | ) | $ | (43 | ) | ||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (3 | ) | (17 | ) | (20 | ) | ||||||||||||
Total realized and unrealized gains (losses) | (3 | ) | (17 | ) | (20 | ) | ||||||||||||
Sales | 1 | — | 1 | |||||||||||||||
Settlements | (6 | ) | 3 | (3 | ) | |||||||||||||
Transfers into Level 3 | (1 | ) | — | (1 | ) | |||||||||||||
Ending balance at September 30, 2013 | $ | 28 | $ | (94 | ) | $ | (66 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | (2 | ) | $ | (16 | ) | $ | (18 | ) | |||||||||
Uranium: | ||||||||||||||||||
Beginning balance at July 1, 2013 | $ | (3 | ) | $ | (a) | $ | (3 | ) | ||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | — | (a) | — | |||||||||||||||
Total realized and unrealized gains (losses) | — | (a) | — | |||||||||||||||
Purchases | (2 | ) | (a) | (2 | ) | |||||||||||||
Ending balance at September 30, 2013 | $ | (5 | ) | $ | (a) | $ | (5 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | (2 | ) | $ | (a) | $ | (2 | ) | ||||||||||
(a) | Not applicable. | |||||||||||||||||
The following table summarizes the changes in the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy for the three months ended September 30, 2012: | ||||||||||||||||||
Net derivative commodity contracts | ||||||||||||||||||
Three Months | Ameren | Ameren | Ameren | |||||||||||||||
Missouri | Illinois | |||||||||||||||||
Fuel oils: | ||||||||||||||||||
Beginning balance at July 1, 2012 | $ | 3 | $ | (a) | $ | 3 | ||||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | 1 | (a) | 1 | |||||||||||||||
Total realized and unrealized gains (losses) | 1 | (a) | 1 | |||||||||||||||
Purchases | 2 | (a) | 2 | |||||||||||||||
Sales | (1 | ) | (a) | (1 | ) | |||||||||||||
Ending balance at September 30, 2012 | $ | 5 | $ | (a) | $ | 5 | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | 2 | $ | (a) | $ | 2 | ||||||||||||
Power(b): | ||||||||||||||||||
Beginning balance at July 1, 2012 | $ | 26 | $ | (221 | ) | $ | (81 | ) | ||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (4 | ) | 2 | (6 | ) | |||||||||||||
Total realized and unrealized gains (losses) | (4 | ) | 2 | (6 | ) | |||||||||||||
Sales | (1 | ) | — | (1 | ) | |||||||||||||
Settlements | (4 | ) | 54 | (1 | ) | |||||||||||||
Transfers out of Level 3 | (2 | ) | — | (2 | ) | |||||||||||||
Ending balance at September 30, 2012 | $ | 15 | $ | (165 | ) | $ | (91 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | (5 | ) | $ | (2 | ) | $ | (7 | ) | |||||||||
Uranium: | ||||||||||||||||||
Beginning balance at July 1, 2012 | $ | (1 | ) | (a) | $ | (1 | ) | |||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (1 | ) | (a) | (1 | ) | |||||||||||||
Total realized and unrealized gains (losses) | (1 | ) | (a) | (1 | ) | |||||||||||||
Ending balance at September 30, 2012 | $ | (2 | ) | (a) | $ | (2 | ) | |||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | (1 | ) | (a) | $ | (1 | ) | |||||||||||
(a) | Not applicable. | |||||||||||||||||
(b) | Ameren amounts include the elimination of financial power contracts between Ameren Illinois and Marketing Company. | |||||||||||||||||
The following table summarizes the changes in the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy for the nine months ended September 30, 2013: | ||||||||||||||||||
Net derivative commodity contracts | ||||||||||||||||||
Nine Months | Ameren | Ameren | Ameren | |||||||||||||||
Missouri | Illinois | |||||||||||||||||
Fuel oils: | ||||||||||||||||||
Beginning balance at January 1, 2013 | $ | 5 | $ | (a) | $ | 5 | ||||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (1 | ) | (a) | (1 | ) | |||||||||||||
Total realized and unrealized gains (losses) | (1 | ) | (a) | (1 | ) | |||||||||||||
Purchases | 2 | (a) | 2 | |||||||||||||||
Sales | (1 | ) | (a) | (1 | ) | |||||||||||||
Settlements | (2 | ) | (a) | (2 | ) | |||||||||||||
Ending balance at September 30, 2013 | $ | 3 | $ | (a) | $ | 3 | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | — | $ | (a) | $ | — | ||||||||||||
Natural gas: | ||||||||||||||||||
Beginning balance at January 1, 2013 | $ | — | $ | — | $ | — | ||||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | — | (1 | ) | (1 | ) | |||||||||||||
Total realized and unrealized gains (losses) | — | (1 | ) | (1 | ) | |||||||||||||
Purchases | — | 1 | 1 | |||||||||||||||
Ending balance at September 30, 2013 | $ | — | $ | — | $ | — | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | — | $ | — | $ | — | ||||||||||||
Power: | ||||||||||||||||||
Beginning balance at January 1, 2013 | $ | 11 | $ | (111 | ) | $ | (100 | ) | ||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | 3 | (2 | ) | 1 | ||||||||||||||
Total realized and unrealized gains (losses) | 3 | (2 | ) | 1 | ||||||||||||||
Purchases | 40 | — | 40 | |||||||||||||||
Sales | 1 | — | 1 | |||||||||||||||
Settlements | (28 | ) | 19 | (9 | ) | |||||||||||||
Transfers into Level 3 | (3 | ) | — | (3 | ) | |||||||||||||
Transfers out of Level 3 | 4 | — | 4 | |||||||||||||||
Ending balance at September 30, 2013 | $ | 28 | $ | (94 | ) | $ | (66 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | — | $ | (7 | ) | $ | (7 | ) | ||||||||||
Uranium: | ||||||||||||||||||
Beginning balance at January 1, 2013 | $ | (2 | ) | $ | (a) | $ | (2 | ) | ||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (2 | ) | (a) | (2 | ) | |||||||||||||
Total realized and unrealized gains (losses) | (2 | ) | (a) | (2 | ) | |||||||||||||
Purchases | (2 | ) | (a) | (2 | ) | |||||||||||||
Settlements | 1 | (a) | 1 | |||||||||||||||
Ending balance at September 30, 2013 | $ | (5 | ) | $ | (a) | $ | (5 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2013 | $ | (2 | ) | $ | (a) | $ | (2 | ) | ||||||||||
(a) | Not applicable. | |||||||||||||||||
The following table summarizes the changes in the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy for the nine months ended September 30, 2012: | ||||||||||||||||||
Net derivative commodity contracts | ||||||||||||||||||
Nine Months | Ameren | Ameren | Ameren | |||||||||||||||
Missouri | Illinois | |||||||||||||||||
Fuel oils: | ||||||||||||||||||
Beginning balance at January 1, 2012 | $ | 3 | $ | (a) | $ | 3 | ||||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (1 | ) | (a) | (1 | ) | |||||||||||||
Total realized and unrealized gains (losses) | (1 | ) | (a) | (1 | ) | |||||||||||||
Purchases | 4 | (a) | 4 | |||||||||||||||
Sales | (2 | ) | (a) | (2 | ) | |||||||||||||
Settlements | (1 | ) | (a) | (1 | ) | |||||||||||||
Transfers into Level 3 | 2 | (a) | 2 | |||||||||||||||
Ending balance at September 30, 2012 | $ | 5 | $ | (a) | $ | 5 | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | (1 | ) | $ | (a) | $ | (1 | ) | ||||||||||
Natural gas: | ||||||||||||||||||
Beginning balance at January 1, 2012 | $ | (14 | ) | $ | (160 | ) | $ | (174 | ) | |||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (2 | ) | (26 | ) | (28 | ) | ||||||||||||
Total realized and unrealized gains (losses) | (2 | ) | (26 | ) | (28 | ) | ||||||||||||
Settlements | 1 | 16 | 17 | |||||||||||||||
Transfers out of Level 3 | 15 | 170 | 185 | |||||||||||||||
Ending balance at September 30, 2012 | $ | — | $ | — | $ | — | ||||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | 7 | $ | — | $ | 7 | ||||||||||||
Power(b): | ||||||||||||||||||
Beginning balance at January 1, 2012 | $ | 21 | $ | (140 | ) | $ | 81 | |||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | 5 | (219 | ) | (174 | ) | |||||||||||||
Total realized and unrealized gains (losses) | 5 | (219 | ) | (174 | ) | |||||||||||||
Purchases | 22 | — | 22 | |||||||||||||||
Sales | (1 | ) | — | (1 | ) | |||||||||||||
Settlements | (28 | ) | 194 | (15 | ) | |||||||||||||
Transfers out of Level 3 | (4 | ) | — | (4 | ) | |||||||||||||
Ending balance at September 30, 2012 | $ | 15 | $ | (165 | ) | $ | (91 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | (1 | ) | $ | (187 | ) | (c) $ | (171 | ) | |||||||||
Uranium: | ||||||||||||||||||
Beginning balance at January 1, 2012 | $ | (1 | ) | $ | (a) | $ | (1 | ) | ||||||||||
Realized and unrealized gains (losses): | ||||||||||||||||||
Included in regulatory assets/liabilities | (1 | ) | (a) | (1 | ) | |||||||||||||
Total realized and unrealized gains (losses) | (1 | ) | (a) | (1 | ) | |||||||||||||
Ending balance at September 30, 2012 | $ | (2 | ) | $ | (a) | $ | (2 | ) | ||||||||||
Change in unrealized gains (losses) related to assets/liabilities held at September 30, 2012 | $ | (1 | ) | $ | (a) | $ | (1 | ) | ||||||||||
(a) | Not applicable. | |||||||||||||||||
(b) | Ameren amounts include the elimination of financial power contracts between Ameren Illinois and Marketing Company. | |||||||||||||||||
(c) | The change in unrealized losses was due to decreases in long-term power prices applied to 20-year Ameren Illinois’ swap contracts, which expire May 2032. | |||||||||||||||||
Schedule Of Transfers Between Fair Value Hierarchy Levels | ' | |||||||||||||||||
The following table summarizes all transfers between fair value hierarchy levels related to derivative commodity contracts for the three and nine months ended September 30, 2013, and 2012: | ||||||||||||||||||
Three Months | Nine Months | |||||||||||||||||
2013 | 2012 | 2013 | 2012 | |||||||||||||||
Ameren - derivative commodity contracts: | ||||||||||||||||||
Transfers into Level 3 / Transfers out of Level 1 - Fuel oils | $ | — | $ | — | $ | — | $ | 2 | ||||||||||
Transfers out of Level 3 / Transfers into Level 2 - Natural gas | — | — | — | 185 | ||||||||||||||
Transfers into Level 3 / Transfers out of Level 2 - Power | (1 | ) | — | (3 | ) | — | ||||||||||||
Transfers out of Level 3 / Transfers into Level 2 - Power | — | (2 | ) | 4 | (4 | ) | ||||||||||||
Net fair value of Level 3 transfers | $ | (1 | ) | $ | (2 | ) | $ | 1 | $ | 183 | ||||||||
Ameren Missouri - derivative commodity contracts: | ||||||||||||||||||
Transfers into Level 3 / Transfers out of Level 1 - Fuel oils | $ | — | $ | — | $ | — | $ | 2 | ||||||||||
Transfers out of Level 3 / Transfers into Level 2 - Natural gas | — | — | — | 15 | ||||||||||||||
Transfers into Level 3 / Transfers out of Level 2 - Power | (1 | ) | — | (3 | ) | — | ||||||||||||
Transfers out of Level 3 / Transfers into Level 2 - Power | — | (2 | ) | 4 | (4 | ) | ||||||||||||
Net fair value of Level 3 transfers | $ | (1 | ) | $ | (2 | ) | $ | 1 | $ | 13 | ||||||||
Ameren Illinois - derivative commodity contracts: | ||||||||||||||||||
Transfers out of Level 3 / Transfers into Level 2 - Natural gas | $ | — | $ | — | $ | — | $ | 170 | ||||||||||
Schedule Of Carrying Amounts And Estimated Fair Values Of Long-Term Debt, Capital Lease Obligations And Preferred Stock | ' | |||||||||||||||||
The following table presents the carrying amounts and estimated fair values of our long-term debt and capital lease obligations and preferred stock at September 30, 2013, and December 31, 2012: | ||||||||||||||||||
30-Sep-13 | 31-Dec-12 | |||||||||||||||||
Carrying | Fair | Carrying | Fair | |||||||||||||||
Amount | Value | Amount | Value | |||||||||||||||
Ameren:(a)(b) | ||||||||||||||||||
Long-term debt and capital lease obligations (including current portion) | $ | 6,158 | $ | 6,596 | $ | 6,157 | $ | 7,110 | ||||||||||
Preferred stock | 142 | 123 | 142 | 123 | ||||||||||||||
Ameren Missouri: | ||||||||||||||||||
Long-term debt and capital lease obligations (including current portion) | $ | 4,006 | $ | 4,227 | $ | 4,006 | $ | 4,625 | ||||||||||
Preferred stock | 80 | 74 | 80 | 74 | ||||||||||||||
Ameren Illinois: | ||||||||||||||||||
Long-term debt (including current portion) | $ | 1,727 | $ | 1,922 | $ | 1,727 | $ | 2,020 | ||||||||||
Preferred stock | 62 | 49 | 62 | 49 | ||||||||||||||
(a) | Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations. | |||||||||||||||||
(b) | Preferred stock along with the noncontrolling interest of EEI is recorded in “Noncontrolling Interests” on the balance sheet. |
Related_Party_Transactions_Tab
Related Party Transactions (Tables) | 9 Months Ended | ||||||||||||||
Sep. 30, 2013 | |||||||||||||||
Related Party Transactions [Abstract] | ' | ||||||||||||||
Schedule of Related Party Transactions | ' | ||||||||||||||
The following table presents the impact on Ameren Missouri and Ameren Illinois of related party transactions for the three and nine months ended September 30, 2013, and 2012. It is based primarily on the agreements discussed above and in Note 14 - Related Party Transactions under Part II, Item 8, of the Form 10-K, and the money pool arrangements discussed in Note 4 - Short-term Debt and Liquidity of this report. | |||||||||||||||
Three Months | Nine Months | ||||||||||||||
Agreement | Income Statement | Ameren | Ameren | Ameren | Ameren | ||||||||||
Line Item | Missouri | Illinois | Missouri | Illinois | |||||||||||
Ameren Missouri power supply | Operating Revenues | 2013 | $ | (b) | $ | (a) | $ | 1 | $ | (a) | |||||
agreements with Ameren Illinois | 2012 | (b) | (a) | (b) | (a) | ||||||||||
Ameren Missouri and Ameren Illinois | Operating Revenues | 2013 | 4 | (b) | 15 | 1 | |||||||||
rent and facility services | 2012 | 5 | (b) | 14 | 1 | ||||||||||
Ameren Missouri and Genco gas | Operating Revenues | 2013 | (b) | (a) | 1 | (a) | |||||||||
transportation agreement | 2012 | (b) | (a) | 1 | (a) | ||||||||||
Transmission services agreement | Operating Revenues | 2013 | (a) | 11 | (a) | 24 | |||||||||
with Marketing Company | 2012 | (a) | 5 | (a) | 11 | ||||||||||
Total Operating Revenues | 2013 | $ | 4 | $ | 11 | $ | 17 | $ | 25 | ||||||
2012 | 5 | 5 | 15 | 12 | |||||||||||
Ameren Illinois power supply | Purchased Power | 2013 | $ | (a) | $ | 46 | $ | (a) | $ | 94 | |||||
agreements with Marketing Company | 2012 | (a) | 83 | (a) | 243 | ||||||||||
Ameren Illinois power supply | Purchased Power | 2013 | (a) | (b) | (a) | 1 | |||||||||
agreements with Ameren Missouri | 2012 | (a) | (b) | (a) | (b) | ||||||||||
Total Purchased Power | 2013 | $ | (a) | $ | 46 | $ | (a) | $ | 95 | ||||||
2012 | (a) | 83 | (a) | 243 | |||||||||||
Ameren Services support services | Other Operations and Maintenance | 2013 | $ | 25 | $ | 22 | $ | 85 | $ | 70 | |||||
agreement | 2012 | 26 | 22 | 81 | 67 | ||||||||||
Insurance premiums(c) | Other Operations and Maintenance | 2013 | (b) | (a) | (b) | (a) | |||||||||
2012 | (b) | (a) | (b) | (a) | |||||||||||
Total Other Operations and | 2013 | $ | 25 | $ | 22 | $ | 85 | $ | 70 | ||||||
Maintenance Expenses | 2012 | 26 | 22 | 81 | 67 | ||||||||||
Money pool borrowings (advances) | Interest Charges | 2013 | $ | (b) | $ | (b) | $ | $1 | $ | (b) | |||||
2012 | (b) | (b) | (b) | (b) | |||||||||||
(a) | Not applicable. | ||||||||||||||
(b) | Amount less than $1 million. | ||||||||||||||
(c) | Represents insurance premiums paid to Missouri Energy Risk Assurance Company, an affiliate, for replacement power |
Commitments_And_Contingencies_
Commitments And Contingencies (Tables) | 9 Months Ended | |||||||||||||||||||||||||||
Sep. 30, 2013 | ||||||||||||||||||||||||||||
Commitments and Contingencies Disclosure [Abstract] | ' | |||||||||||||||||||||||||||
Schedule of Insurance Coverage at Callaway Energy Center | ' | |||||||||||||||||||||||||||
The following table presents insurance coverage at Ameren Missouri’s Callaway energy center at September 30, 2013. The property coverage and the nuclear liability coverage must be renewed on April 1 and January 1, respectively, of each year. | ||||||||||||||||||||||||||||
Type and Source of Coverage | Maximum Coverages | Maximum Assessments | ||||||||||||||||||||||||||
for Single Incidents | ||||||||||||||||||||||||||||
Public liability and nuclear worker liability: | ||||||||||||||||||||||||||||
American Nuclear Insurers | $ | 375 | $ | — | ||||||||||||||||||||||||
Pool participation | 13,312 | (a) | 128 | (b) | ||||||||||||||||||||||||
$ | 13,687 | (c) | $ | 128 | ||||||||||||||||||||||||
Property damage: | ||||||||||||||||||||||||||||
Nuclear Electric Insurance Ltd. | $ | 2,250 | (d) | $ | 23 | (e) | ||||||||||||||||||||||
European Mutual Association for Nuclear Insurance | 500 | (f) | — | |||||||||||||||||||||||||
$ | 2,750 | $ | 23 | |||||||||||||||||||||||||
Replacement power: | ||||||||||||||||||||||||||||
Nuclear Electric Insurance Ltd. | $ | 490 | (g) | $ | 9 | (e) | ||||||||||||||||||||||
Missouri Energy Risk Assurance Company | 64 | (h) | — | |||||||||||||||||||||||||
(a) | Provided through mandatory participation in an industry-wide retrospective premium assessment program. | |||||||||||||||||||||||||||
(b) | Retrospective premium under Price-Anderson. This is subject to retrospective assessment with respect to a covered loss in excess of $375 million in the event of an incident at any licensed United States commercial reactor, payable at $19 million per year. | |||||||||||||||||||||||||||
(c) | Limit of liability for each incident under the Price-Anderson liability provisions of the Atomic Energy Act of 1954, as amended. A company could be assessed up to $128 million per incident for each licensed reactor it operates with a maximum of $19 million per incident to be paid in a calendar year for each reactor. This limit is subject to change to account for the effects of inflation and changes in the number of licensed reactors. | |||||||||||||||||||||||||||
(d) | Nuclear Electric Insurance Ltd. provides $2.25 billion in property damage, decontamination, and premature decommissioning insurance. There is a $1.7 billion sublimit for non-radiation events of which the top $200 million is a shared limit with other generators purchasing this coverage and includes one free reinstatement. | |||||||||||||||||||||||||||
(e) | All Nuclear Electric Insurance Ltd. insured plants could be subject to assessments should losses exceed the accumulated funds from Nuclear Electric Insurance Ltd. | |||||||||||||||||||||||||||
(f) | European Mutual Association for Nuclear Insurance provides $500 million in excess of the $2.25 billion property coverage and $1.7 billion non-radiation coverage. | |||||||||||||||||||||||||||
(g) | Provides replacement power cost insurance in the event of a prolonged accidental outage at our nuclear energy center. Weekly indemnity up to $4.5 million for 52 weeks, which commences after the first eight weeks of an outage, plus up to $3.6 million per week for a minimum of 71 weeks thereafter for a total not exceeding the policy limit of $490 million. Effective April 1, 2013, non-radiation events are sub-limited to $327.6 million. | |||||||||||||||||||||||||||
(h) | Provides replacement power cost insurance in the event of a prolonged accidental outage at our nuclear energy center. The coverage commences after the first 52 weeks of insurance coverage from Nuclear Electric Insurance Ltd. and is for a weekly indemnity up to $900,000 for 71 weeks in excess of the $3.6 million per week set forth above. Missouri Energy Risk Assurance Company LLC is an affiliate and has reinsured this coverage with third-party insurance companies. See Note 9 - Related Party Transactions for more information on this affiliate transaction. | |||||||||||||||||||||||||||
Schedule of Estimated Purchase Commitments | ' | |||||||||||||||||||||||||||
The table below presents our estimated fuel, purchased power, and other commitments at September 30, 2013. Ameren’s and Ameren Missouri’s purchased power obligations include a 102-megawatt power purchase agreement with a wind farm operator that expires in 2024. Ameren’s and Ameren Illinois’ purchased power obligations include the Ameren Illinois power purchase agreements entered into as part of the IPA-administered power procurement process. Included in the Other column are minimum purchase commitments under contracts for equipment, design and construction, and meter reading services at September 30, 2013. Ameren's and Ameren Illinois' Other column also include obligations related to IEIMA. In addition, the Other column includes Ameren's and Ameren Missouri's obligations related to energy efficiency programs under the MEEIA as approved by the MoPSC's December 2012 electric rate order. The order provides that, beginning in 2013, Ameren Missouri will invest approximately $147 million over three years for energy efficiency programs. | ||||||||||||||||||||||||||||
Coal | Natural | Nuclear | Purchased | Methane | Other | Total | ||||||||||||||||||||||
Gas | Fuel | Power(a) | Gas | |||||||||||||||||||||||||
Ameren:(b) | ||||||||||||||||||||||||||||
2013 | $ | 605 | $ | 109 | $ | 17 | $ | 162 | $ | 1 | $ | 87 | $ | 981 | ||||||||||||||
2014 | 617 | 292 | 68 | 302 | 3 | 158 | 1,440 | |||||||||||||||||||||
2015 | 640 | 155 | 63 | 154 | 4 | 114 | 1,130 | |||||||||||||||||||||
2016 | 665 | 85 | 81 | 67 | 4 | 64 | 966 | |||||||||||||||||||||
2017 | 683 | 47 | 58 | 44 | 5 | 56 | 893 | |||||||||||||||||||||
Thereafter | 245 | 100 | 216 | 501 | 97 | 246 | 1,405 | |||||||||||||||||||||
Total | $ | 3,455 | $ | 788 | $ | 503 | $ | 1,230 | $ | 114 | $ | 725 | $ | 6,815 | ||||||||||||||
Ameren Missouri: | ||||||||||||||||||||||||||||
2013 | $ | 605 | $ | 27 | $ | 17 | $ | 3 | $ | 1 | $ | 66 | $ | 719 | ||||||||||||||
2014 | 617 | 50 | 68 | 19 | 3 | 127 | 884 | |||||||||||||||||||||
2015 | 640 | 30 | 63 | 19 | 4 | 85 | 841 | |||||||||||||||||||||
2016 | 665 | 16 | 81 | 19 | 4 | 40 | 825 | |||||||||||||||||||||
2017 | 683 | 11 | 58 | 19 | 5 | 32 | 808 | |||||||||||||||||||||
Thereafter | 245 | 28 | 216 | 129 | 97 | 144 | 859 | |||||||||||||||||||||
Total | $ | 3,455 | $ | 162 | $ | 503 | $ | 208 | $ | 114 | $ | 494 | $ | 4,936 | ||||||||||||||
Ameren Illinois: | ||||||||||||||||||||||||||||
2013 | $ | — | $ | 82 | $ | — | $ | 159 | $ | — | $ | 9 | $ | 250 | ||||||||||||||
2014 | — | 242 | — | 283 | — | 22 | 547 | |||||||||||||||||||||
2015 | — | 125 | — | 135 | — | 24 | 284 | |||||||||||||||||||||
2016 | — | 69 | — | 48 | — | 24 | 141 | |||||||||||||||||||||
2017 | — | 36 | — | 25 | — | 24 | 85 | |||||||||||||||||||||
Thereafter | — | 72 | — | 372 | — | 102 | 546 | |||||||||||||||||||||
Total | $ | — | $ | 626 | $ | — | $ | 1,022 | $ | — | $ | 205 | $ | 1,853 | ||||||||||||||
(a) | The purchased power amounts for Ameren and Ameren Illinois includes twenty-year agreements for renewable energy credits that were entered into in December 2010 with various renewable energy suppliers. The agreements contain a provision that allows Ameren Illinois to reduce the quantity purchased in the event that Ameren Illinois would not be able to recover the costs associated with the renewable energy credits. | |||||||||||||||||||||||||||
(b) | Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations. | |||||||||||||||||||||||||||
Schedule of Estimated Capital Costs to Comply With Existing and Known Emissions Related Regulations | ' | |||||||||||||||||||||||||||
Continuing Operations: | ||||||||||||||||||||||||||||
2013 | 2014 - 2017 | 2018 - 2022 | Total | |||||||||||||||||||||||||
AMO(a) | $ | 105 | $ | 215 | - | $ | 260 | $ | 795 | - | $ | 975 | $ | 1,115 | - | $ | 1,340 | |||||||||||
(a) | Ameren Missouri’s expenditures are expected to be recoverable from ratepayers. | |||||||||||||||||||||||||||
Discontinued Operations: | ||||||||||||||||||||||||||||
2013 | 2014 - 2017 | 2018 - 2022 | Total | |||||||||||||||||||||||||
Genco(a) | $ | 30 | $ | 100 | - | $ | 125 | $ | 220 | - | $ | 270 | $ | 350 | - | $ | 425 | |||||||||||
AERG | 5 | 20 | - | 25 | 20 | - | 25 | 45 | - | 55 | ||||||||||||||||||
Total(b) | $ | 35 | $ | 120 | - | $ | 150 | $ | 240 | - | $ | 295 | $ | 395 | - | $ | 480 | |||||||||||
(a) | Includes estimated costs of approximately $20 million annually, excluding capitalized interest, from 2013 through 2017 for construction of two scrubbers at the Newton energy center. | |||||||||||||||||||||||||||
(b) | Assumes the Merchant Generation facilities are owned by Ameren. | |||||||||||||||||||||||||||
Schedule of Estimated Obligations for Manufactured Gas Plant Remediation | ' | |||||||||||||||||||||||||||
The following table presents, as of September 30, 2013, the estimated obligation to complete the remediation of these former MGP sites. | ||||||||||||||||||||||||||||
Estimate | Recorded | |||||||||||||||||||||||||||
Low | High | Liability(a) | ||||||||||||||||||||||||||
Ameren | $ | 251 | $ | 337 | $ | 251 | ||||||||||||||||||||||
Ameren Missouri | 5 | 6 | 5 | |||||||||||||||||||||||||
Ameren Illinois | 246 | 331 | 246 | |||||||||||||||||||||||||
(a) | Recorded liability represents the estimated minimum probable obligations, as no other amount within the range was a better estimate. | |||||||||||||||||||||||||||
Schedule of Asbestors-Related Litigation Pending Lawsuits | ' | |||||||||||||||||||||||||||
The following table presents the pending asbestos-related lawsuits filed against the Ameren Companies as of September 30, 2013: | ||||||||||||||||||||||||||||
Ameren | Ameren | Ameren | Total(a) | |||||||||||||||||||||||||
Missouri | Illinois | |||||||||||||||||||||||||||
1 | 55 | 63 | 85 | |||||||||||||||||||||||||
(a) | Total does not equal the sum of the subsidiary unit lawsuits because some of the lawsuits name multiple Ameren entities as defendants. |
Retirement_Benefits_Tables
Retirement Benefits (Tables) | 9 Months Ended | |||||||||||||||||||||||||||||||
Sep. 30, 2013 | ||||||||||||||||||||||||||||||||
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract] | ' | |||||||||||||||||||||||||||||||
Components Of Net Periodic Benefit Cost | ' | |||||||||||||||||||||||||||||||
The following table presents the components of the net periodic benefit cost for Ameren’s pension and postretirement benefit plans for the three and nine months ended September 30, 2013, and 2012: | ||||||||||||||||||||||||||||||||
Pension Benefits (a) | Postretirement Benefits (a) | |||||||||||||||||||||||||||||||
Three Months | Nine Months | Three Months | Nine Months | |||||||||||||||||||||||||||||
2013 | 2012 | 2013 | 2012 | 2013 | 2012 | 2013 | 2012 | |||||||||||||||||||||||||
Service cost | $ | 23 | $ | 20 | $ | 69 | $ | 61 | $ | 6 | $ | 5 | $ | 17 | $ | 16 | ||||||||||||||||
Interest cost | 40 | 42 | 121 | 125 | 11 | 12 | 34 | 36 | ||||||||||||||||||||||||
Expected return on plan assets | (54 | ) | (52 | ) | (162 | ) | (156 | ) | (16 | ) | (14 | ) | (47 | ) | (42 | ) | ||||||||||||||||
Amortization of: | ||||||||||||||||||||||||||||||||
Transition obligation | — | — | — | — | — | 1 | — | 1 | ||||||||||||||||||||||||
Prior service cost (benefit) | (1 | ) | (1 | ) | (3 | ) | (3 | ) | (1 | ) | (1 | ) | (3 | ) | (3 | ) | ||||||||||||||||
Actuarial loss | 23 | 19 | 69 | 56 | 2 | 1 | 6 | 3 | ||||||||||||||||||||||||
Net periodic benefit cost | $ | 31 | $ | 28 | $ | 94 | $ | 83 | $ | 2 | $ | 4 | $ | 7 | $ | 11 | ||||||||||||||||
(a) | Excludes the EEI plans as they are included in discontinued operations. | |||||||||||||||||||||||||||||||
Summary Of Benefit Plan Costs Incurred | ' | |||||||||||||||||||||||||||||||
Ameren Missouri and Ameren Illinois are responsible for their respective shares of Ameren’s pension and postretirement costs. The following table presents the pension costs and the postretirement benefit costs incurred for the three and nine months ended September 30, 2013, and 2012: | ||||||||||||||||||||||||||||||||
Pension Costs | Postretirement Costs | |||||||||||||||||||||||||||||||
Three Months | Nine Months | Three Months | Nine Months | |||||||||||||||||||||||||||||
2013 | 2012 | 2013 | 2012 | 2013 | 2012 | 2013 | 2012 | |||||||||||||||||||||||||
Ameren Missouri | $ | 18 | $ | 16 | $ | 54 | $ | 48 | $ | 2 | $ | 2 | $ | 7 | $ | 7 | ||||||||||||||||
Ameren Illinois | 10 | 9 | 31 | 27 | (b) | 1 | (b) | 3 | ||||||||||||||||||||||||
Other | 3 | 3 | 9 | 8 | (b) | 1 | (b) | 1 | ||||||||||||||||||||||||
Ameren(a) | $ | 31 | $ | 28 | $ | 94 | $ | 83 | $ | 2 | $ | 4 | $ | 7 | $ | 11 | ||||||||||||||||
(a) | Includes amounts for Ameren registrants and nonregistrant subsidiaries, but excludes the EEI plans as they are included in discontinued operations. | |||||||||||||||||||||||||||||||
(b) | Less than $1 million. |
Segment_Information_Tables
Segment Information (Tables) | 9 Months Ended | ||||||||||||||||||||
Sep. 30, 2013 | |||||||||||||||||||||
Segment Reporting [Abstract] | ' | ||||||||||||||||||||
Schedule Of Segment Reporting Information By Segment | ' | ||||||||||||||||||||
The following table presents information about the revenues and specified items included in net income attributable to Ameren Corporation from continuing operations for the three and nine months ended September 30, 2013, and 2012, and total assets as of September 30, 2013, and December 31, 2012. | |||||||||||||||||||||
Three Months | Ameren | Ameren | Other | Intersegment | Consolidated | ||||||||||||||||
Missouri | Illinois | Eliminations | |||||||||||||||||||
2013 | |||||||||||||||||||||
External revenues | $ | 1,088 | $ | 547 | $ | 3 | $ | — | $ | 1,638 | |||||||||||
Intersegment revenues | 5 | — | 1 | (6 | ) | — | |||||||||||||||
Net income (loss) attributable to Ameren Corporation from continuing operations | 238 | 77 | (10 | ) | — | 305 | |||||||||||||||
2012 | |||||||||||||||||||||
External revenues | $ | 1,059 | $ | 647 | $ | 3 | $ | — | $ | 1,709 | |||||||||||
Intersegment revenues | 5 | 1 | — | (6 | ) | — | |||||||||||||||
Net income (loss) attributable to Ameren Corporation from continuing operations | 236 | 71 | 2 | — | 309 | ||||||||||||||||
Nine Months | |||||||||||||||||||||
2013 | |||||||||||||||||||||
External revenues | $ | 2,760 | $ | 1,744 | $ | 12 | $ | — | $ | 4,516 | |||||||||||
Intersegment revenues | 18 | 3 | 2 | (23 | ) | — | |||||||||||||||
Net income (loss) attributable to Ameren Corporation from continuing operations | 362 | 139 | (37 | ) | — | 464 | |||||||||||||||
2012 | |||||||||||||||||||||
External revenues | $ | 2,583 | $ | 1,935 | $ | 5 | $ | — | $ | 4,523 | |||||||||||
Intersegment revenues | 16 | 1 | 2 | (19 | ) | — | |||||||||||||||
Net income (loss) attributable to Ameren Corporation from continuing operations | 400 | 130 | (23 | ) | — | 507 | |||||||||||||||
As of September 30, 2013: | |||||||||||||||||||||
Total assets | $ | 13,231 | $ | 7,439 | $ | 1,375 | $ | (1,055 | ) | $ | 20,990 | (a) | |||||||||
As of December 31, 2012: | |||||||||||||||||||||
Total assets | $ | 13,043 | $ | 7,282 | $ | 1,228 | $ | (934 | ) | $ | 20,619 | (a) | |||||||||
(a) Excludes “Assets of discontinued operations.” See Note 2 - Divestiture Transactions and Discontinued Operations for additional information. |
Summary_Of_Significant_Account3
Summary Of Significant Accounting Policies (Narrative) (Detail) (USD $) | 9 Months Ended | 9 Months Ended | 9 Months Ended | 1 Months Ended | 9 Months Ended | 0 Months Ended | ||||||||
In Millions, except Per Share data, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Dec. 31, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Dec. 31, 2012 | Sep. 30, 2013 | Sep. 30, 2013 | Dec. 31, 2012 | Jan. 31, 2013 | Sep. 30, 2013 | Mar. 14, 2013 | Oct. 11, 2013 | |
Union Electric Company | Union Electric Company | Union Electric Company | Ameren Illinois Company | Electric Energy, Inc | Electric Energy, Inc | Performance Shares | Performance Shares | Elgin, Gibson City and Grand Tower Energy Centers | Subsequent Event [Member] | |||||
Ameren Energy Generating Company | Elgin, Gibson City and Grand Tower Energy Centers | |||||||||||||
Ameren Energy Generating Company | ||||||||||||||
Basis Of Presentation And Significant Accounting Policies [Line Items] | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | |
Ownership interest | ' | ' | ' | ' | ' | ' | ' | 80.00% | ' | ' | ' | ' | ' | |
Initial payment received | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | $100 | ' | |
Additional payment received | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 37.5 | |
Identified immaterial error | ' | 49 | ' | ' | 49 | ' | ' | ' | ' | ' | ' | ' | ' | |
Fair value of each share unit, per share | ' | ' | ' | ' | ' | ' | ' | ' | ' | $31.19 | $31.19 | [1] | ' | ' |
Closing common share price | ' | ' | $30.72 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | |
Performance period | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | '3 years | ' | ' | |
Three-year risk-free rate | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 0.36% | ' | ' | |
Risk free interest rate period | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | '3 years | ' | ' | |
Volatility rate, minimum | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 12.00% | ' | ' | |
Volatility rate, maximum | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 21.00% | ' | ' | |
Book value or renewable energy credits | 19 | ' | 14 | 19 | ' | 14 | ' | ' | ' | ' | ' | ' | ' | |
Unrecognized tax benefits (detriments) | 86 | ' | ' | 27 | ' | ' | -2 | ' | ' | ' | ' | ' | ' | |
Unrecognized tax benefits (detriments) that would impact effective tax rate | 51 | ' | ' | 2 | ' | ' | -1 | ' | ' | ' | ' | ' | ' | |
Increase in unrecognized tax benefits that would impact effective tax rate | 50 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | |
Reduction to unrecognized tax benefits due to IRS guidance | 113 | ' | ' | 103 | ' | ' | 5 | ' | ' | ' | ' | ' | ' | |
Estimated unrecognized tax decreases resulting from settlements with taxing authorities | $23 | ' | ' | $15 | ' | ' | $0 | ' | ' | ' | ' | ' | ' | |
Percentage of EEI not owned by Ameren | ' | ' | ' | ' | ' | ' | ' | 20.00% | 20.00% | ' | ' | ' | ' | |
[1] | Includes performance share units (share units) granted to certain executive and nonexecutive officers and other eligible employees in 2013 under the 2006 Plan. |
Summary_Of_Significant_Account4
Summary Of Significant Accounting Policies Summary of Significant Accounting Policies (Schedule of Weighted Average Number of Common Shares Outstanding) (Details) (USD $) | 3 Months Ended | 9 Months Ended | ||||||
In Millions, except Per Share data, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | ||||
Weighted Average Number of Shares Outstanding Reconciliation [Abstract] | ' | ' | ' | ' | ||||
Continuing Operations | $305 | $309 | $464 | $507 | ||||
Discontinued Operations | -3 | 65 | -212 | -325 | ||||
Net Income (Loss) Attributable to Ameren Corporation | $302 | $374 | $252 | $182 | ||||
Average Common Shares Outstanding - Basic | 242.6 | 242.6 | 242.6 | 242.6 | ||||
Assumed Settlement of Performance Share Units | 2.5 | 0.3 | 1.8 | 0.3 | ||||
Average Common Shares Outstanding - Diluted | 245.1 | 242.9 | 244.4 | 242.9 | ||||
Continuing Operations - Basic | $1.26 | $1.28 | $1.92 | $2.09 | ||||
Discontinued Operations - Basic | ($0.01) | $0.26 | ($0.88) | ($1.34) | ||||
Earnings per Common Share - Basic | $1.25 | $1.54 | $1.04 | $0.75 | ||||
Continuing Operations - Diluted | $1.25 | $1.28 | $1.91 | $2.09 | ||||
Discontinued Operations - Diluted | ($0.01) | $0.26 | ($0.88) | ($1.34) | ||||
Earnings per Common Share - Diluted | $1.24 | $1.54 | $1.03 | $0.75 | ||||
Average Performance Share Units Excluded From Calculation | 0 | [1] | 1 | [1] | 0.1 | [1] | 1 | [1] |
[1] | Weighted-average number of performance share units that were excluded from the “Assumed settlement of performance share units†provided above because the performance or market conditions related to the awards had not yet been met. |
Summary_Of_Significant_Account5
Summary Of Significant Accounting Policies Summary of Significant Accounting Policies (Summary of Nonvested Shares Related To Long-Term Incentive Plan) (Details) (Performance Shares, USD $) | 1 Months Ended | 9 Months Ended | |
Jan. 31, 2013 | Sep. 30, 2013 | ||
Performance Shares | ' | ' | |
Share Units | ' | ' | |
Share Units, Nonvested as of January 1, 2013 | 1,192,487 | 1,192,487 | |
Share Units, Granted | ' | 837,199 | [1] |
Share Units, Forfeitures | ' | -7,757 | |
Share Units, Vested | ' | -131,960 | [2] |
Share Units, Nonvested as of September 30, 2013 | ' | 1,889,969 | |
Weighted-average Fair Value per Unit at Grant Date | ' | ' | |
Weighted-average Fair Value per Unit, Nonvested as of January 1, 2013 | $33.56 | $33.56 | |
Weighted-average Fair Value per Unit, Grants | $31.19 | $31.19 | [1] |
Weighted-average Fair Value per Unit, Forfeitures | ' | $32.66 | |
Weighted-average Fair Value per Unit, Vested | ' | $31.30 | [2] |
Weighted-average Fair Value per Unit, Nonvested as of September 30, 2013 | ' | $32.67 | |
Performance period | ' | '3 years | |
[1] | Includes performance share units (share units) granted to certain executive and nonexecutive officers and other eligible employees in 2013 under the 2006 Plan. | ||
[2] | Share units vested due to the attainment of retirement eligibility by certain employees. Actual shares issued for retirement-eligible employees will vary depending on actual performance over the three-year measurement period. |
Summary_Of_Significant_Account6
Summary Of Significant Accounting Policies (Schedule Of Amortization Expense Based On Usage Of Renewable Energy Credits And Emission Allowances) (Detail) (REC and Emission Allowances, USD $) | 3 Months Ended | 9 Months Ended | |||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | |
Finite-Lived Intangible Assets [Line Items] | ' | ' | ' | ' | |
Amortization of intangible assets | $2 | $2 | $9 | $2 | |
Union Electric Company | ' | ' | ' | ' | |
Finite-Lived Intangible Assets [Line Items] | ' | ' | ' | ' | |
Amortization of intangible assets | ' | 1 | 1 | [1] | 1 |
Ameren Illinois Company | ' | ' | ' | ' | |
Finite-Lived Intangible Assets [Line Items] | ' | ' | ' | ' | |
Amortization of intangible assets | $2 | $1 | $9 | $1 | |
[1] | Less than $1 million. |
Summary_Of_Significant_Account7
Summary Of Significant Accounting Policies (Schedule Of Excise Taxes) (Detail) (USD $) | 3 Months Ended | 9 Months Ended | ||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 |
Accounting Policies [Line Items] | ' | ' | ' | ' |
Excise tax expense | $59 | $55 | $163 | $148 |
Union Electric Company | ' | ' | ' | ' |
Accounting Policies [Line Items] | ' | ' | ' | ' |
Excise tax expense | 49 | 46 | 120 | 111 |
Ameren Illinois Company | ' | ' | ' | ' |
Accounting Policies [Line Items] | ' | ' | ' | ' |
Excise tax expense | $10 | $9 | $43 | $37 |
Summary_Of_Significant_Account8
Summary Of Significant Accounting Policies Summary of Significant Accounting Policies (Schedule of Asset Retirement Obligations) (Details) (USD $) | 9 Months Ended | ||
In Millions, unless otherwise specified | Sep. 30, 2013 | Dec. 31, 2012 | |
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] | ' | ' | |
Balance at December 31, 2012 | $375 | [1] | ' |
Liabilities incurred | 0 | [1] | ' |
Liabilities settled | 1 | [1],[2] | ' |
Accretion in 2013 | 15 | [1],[3] | ' |
Change in estimates | 2 | [1],[4] | ' |
Balance at September 30, 2013 | 392 | [1] | ' |
Nuclear decommissioning trust fund | 459 | 408 | |
Union Electric Company | ' | ' | |
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] | ' | ' | |
Balance at December 31, 2012 | 346 | [1] | ' |
Liabilities incurred | 0 | [1] | ' |
Liabilities settled | 1 | [1],[2] | ' |
Accretion in 2013 | 14 | [1],[3] | ' |
Change in estimates | 2 | [1],[4] | ' |
Balance at September 30, 2013 | 362 | [1] | ' |
Nuclear decommissioning trust fund | 459 | 408 | |
Ameren Illinois Company | ' | ' | |
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] | ' | ' | |
Balance at December 31, 2012 | 3 | [5] | ' |
Liabilities incurred | 0 | [5] | ' |
Liabilities settled | 1 | [2],[5] | ' |
Accretion in 2013 | 1 | [2],[3],[5] | ' |
Change in estimates | 1 | [2],[4],[5] | ' |
Balance at September 30, 2013 | 3 | [5] | ' |
Other | ' | ' | |
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] | ' | ' | |
Balance at December 31, 2012 | 26 | [6] | ' |
Liabilities incurred | 0 | [6] | ' |
Liabilities settled | 1 | [2],[6] | ' |
Accretion in 2013 | 1 | [3],[6] | ' |
Change in estimates | 1 | [2],[4],[6] | ' |
Balance at September 30, 2013 | $27 | [6] | ' |
[1] | The nuclear decommissioning trust fund assets of $459 million and $408 million as of September 30, 2013, and December 31, 2012, respectively, were restricted for decommissioning of the Callaway energy center. | ||
[2] | Less than $1 million. | ||
[3] | Accretion was recorded as an increase to regulatory assets at Ameren Missouri and Ameren Illinois. | ||
[4] | Ameren Missouri changed its fair value estimates for asbestos removal and certain CCR storage facilities. | ||
[5] | Balance included in “Other deferred credits and liabilities†on the balance sheet. | ||
[6] | Represents amounts for the Meredosia and Hutsonville energy centers. Pursuant to the transaction agreement to divest New AER to IPH, Ameren will retain the AROs associated with the Meredosia and Hutsonville energy centers. See Note 2 - Divestiture Transactions and Discontinued Operations for additional information. |
Summary_Of_Significant_Account9
Summary Of Significant Accounting Policies (Equity Changes Attributable To Noncontrolling Interest) (Detail) (USD $) | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | ||||||||||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | ||||
Electric Energy, Inc | Electric Energy, Inc | Noncontrolling Interest | Noncontrolling Interest | Noncontrolling Interest | Noncontrolling Interest | |||||||||
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward] | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||||
Noncontrolling interest, beginning of period | $151 | [1] | $145 | [1] | $151 | [1] | $149 | [1] | ' | ' | ' | ' | ' | ' |
Net income from continuing operations attributable to noncontrolling interests | 2 | 2 | 5 | 5 | ' | ' | ' | ' | ' | ' | ||||
Net loss from discontinued operations attributable to noncontrolling interests | ' | -2 | ' | -6 | ' | ' | ' | ' | ' | ' | ||||
Dividends paid to noncontrolling interest holders | -2 | -2 | -5 | -5 | ' | ' | ' | ' | ' | ' | ||||
Other comprehensive Income attributable to noncontrolling interest | ' | [2] | -9 | [2] | ' | [2] | -9 | [2] | ' | ' | ' | ' | ' | ' |
Noncontrolling interest, end of period | 151 | [1] | 152 | [1] | 151 | [1] | 152 | [1] | ' | ' | ' | ' | ' | ' |
Percentage of EEI not owned by Ameren | ' | ' | ' | ' | 20.00% | 20.00% | ' | ' | ' | ' | ||||
Pension and other postretirement benefit plan activity, tax expense (benefit) | ($5) | $0 | $3 | $0 | ' | ' | $0 | $6 | $0 | $6 | ||||
[1] | Includes the 20% EEI ownership interest not owned by Ameren. The assets and liabilities of EEI were consolidated in Ameren’s balance sheet at a 100% ownership level and were included in “Current assets of discontinued operations†and “Current liabilities of discontinued operations.†The 20% ownership interest not owned by Ameren was included in “Noncontrolling interests†on Ameren’s September 30, 2013, and December 31, 2012 balance sheets. See Note 2 - Divestiture Transactions and Discontinued Operations for additional information. | |||||||||||||
[2] | Represents the noncontrolling interest of EEI’s pension and other postretirement benefit plan activity, net of income taxes of $-, $6, $-, and $6, respectively. |
Divestiture_Transactions_and_D2
Divestiture Transactions and Discontinued Operations (Narrative) (Details) (USD $) | 0 Months Ended | 9 Months Ended | 0 Months Ended | 3 Months Ended | 9 Months Ended | 0 Months Ended | 0 Months Ended | 3 Months Ended | 0 Months Ended | |||||||||||||||
Mar. 14, 2013 | Sep. 30, 2013 | Dec. 31, 2012 | Mar. 14, 2013 | Sep. 30, 2013 | Mar. 31, 2013 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Mar. 14, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Mar. 31, 2013 | Mar. 14, 2013 | Mar. 14, 2013 | Mar. 14, 2013 | Jun. 30, 2013 | Oct. 11, 2013 | Oct. 11, 2013 | Oct. 11, 2013 | |||
D | New Ameren Energy Resources Company, LLC | New Ameren Energy Resources Company, LLC | New Ameren Energy Resources Company, LLC | New Ameren Energy Resources Company, LLC | New Ameren Energy Resources Company, LLC | Meredosia and Hutsonville Energy Centers [Member] | Notes Payable, Other Payables [Member] | Notes Payable, Other Payables [Member] | Senior Notes [Member] | Illinois Power Holdings, LLC [Member] | Elgin, Gibson City and Grand Tower Energy Centers | Elgin, Gibson City and Grand Tower Energy Centers | Elgin, Gibson City and Grand Tower Energy Centers | Initial Payment Received [Member] | Maximum | Claimed Manufacturing Exemptions And Credits [Member] | Subsequent Event [Member] | Subsequent Event [Member] | Subsequent Event [Member] | |||||
disposal_groups | center | Ameren Energy Generating Company | New Ameren Energy Resources Company, LLC | New Ameren Energy Resources Company, LLC | Ameren Energy Generating Company | Ameren Energy Generating Company | New Ameren Energy Resources Company, LLC | Ameren Energy Generating Company | Elgin, Gibson City and Grand Tower Energy Centers | Additional Payment Received [Member] | Total Payment Received [Member] | |||||||||||||
appraiser | ||||||||||||||||||||||||
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Proceeds from Sales of Business, Affiliate and Productive Assets | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | $100,000,000 | $100,000,000 | ' | ' | ' | $37,500,000 | $137,500,000 | ||
Escrow Deposit, Reserve Period | ' | '2 years | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Period to distribution proceeds from sale of business | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | '2 years | ' | ||
Gain (Loss) Related to Litigation Settlement | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 7,000,000 | ' | ' | ' | ||
Pension and other postretirement obligations assumed by counterparty | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 32,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Defined benefit plan assets assumed by counterparty | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 15,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Asset retirement obligations | ' | 392,000,000 | [1] | 375,000,000 | [1] | ' | ' | ' | ' | ' | 27,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Converted instrument, period for conversion | ' | ' | ' | ' | ' | ' | ' | ' | ' | '24 months | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Cash Collateral for Borrowed Securities | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 27,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Aggregate principal amount of senior notes | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 825,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Transaction agreement, cash retained by counterparty | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 85,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Gain (Loss) on Contract Termination | 25,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Contract Covenant Compliance, Number of Business Days | 3 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Significant Acquisitions and Disposals, Number Appraisers | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 3 | ' | ' | ' | ' | ' | ' | ||
Impairment of assets to be disposed of | ' | ' | ' | ' | 7,000,000 | ' | 175,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Discontinued operations deferred tax expense | ' | ' | ' | ' | 1,000,000 | 96,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Number of Energy Centers Impaired | ' | ' | ' | ' | ' | ' | 3 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Discontinued operations deferred tax benefit | ' | ' | ' | ' | 3,000,000 | 72,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Disposal group, fair value | ' | ' | ' | ' | ' | ' | ' | 133,000,000 | ' | ' | ' | ' | ' | 137,500,000 | 133,000,000 | ' | ' | ' | ' | ' | ' | ' | ||
Obligation to provide credit support, period | ' | ' | ' | '24 months | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Buyer's indemnification guarantee obligation | ' | ' | ' | 25,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Buyer's indemnification guarantee obligation, period | ' | ' | ' | '24 months | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Period for working capital adjustment | ' | ' | ' | '120 days | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Transitional services to be provided to buyer, period | ' | ' | ' | '6 months | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | '12 months | ' | ' | ' | ' | ||
Transitional services to be provided to buyer at no charge, period | ' | ' | ' | '90 days | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Transitional services to be provided to buyer at no charge, maximum amount | ' | ' | ' | 5,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
Transitional services to be provided to buyer, additional period | ' | ' | ' | '6 months | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
SignificantAcquisitionsAndDisposalsExpectedAdditionalSaleProceedsMaximum | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | $15,000,000 | ' | ' | ||
Discontinued Operations, Number of Disposal Groups | 2 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ||
[1] | The nuclear decommissioning trust fund assets of $459 million and $408 million as of September 30, 2013, and December 31, 2012, respectively, were restricted for decommissioning of the Callaway energy center. |
Divestiture_Transactions_and_D3
Divestiture Transactions and Discontinued Operations (Components of Discontinued Operations in Consolidated Statement of Income) (Details) (USD $) | 3 Months Ended | 9 Months Ended | ||||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | ||
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | ' | ' | ' | ' | ||
Operating revenues | $311 | $293 | $878 | $797 | ||
Operating expenses | -309 | -237 | -1,034 | [1] | -1,301 | [2] |
Operating income (loss) | 2 | 56 | -156 | -504 | ||
Other income (loss) | ' | ' | -1 | ' | ||
Interest charges | -9 | -14 | -31 | -43 | ||
Income (loss) before income taxes | -7 | 42 | -188 | -547 | ||
Income tax (expense) benefit | 4 | 21 | -24 | 216 | ||
Income (Loss) from discontinued operations, net of taxes | -3 | 63 | -212 | -331 | ||
New Ameren Energy Resources Company, LLC | ' | ' | ' | ' | ||
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | ' | ' | ' | ' | ||
Impairment of Long-Lived Assets to be Disposed of | 7 | ' | 175 | ' | ||
Duck Creek Energy Center [Member] | New Ameren Energy Resources Company, LLC | ' | ' | ' | ' | ||
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | ' | ' | ' | ' | ||
Impairment of Long-Lived Assets to be Disposed of | ' | ' | ' | $628 | ||
[1] | Includes a noncash pretax impairment charge of $175 million for the nine months ended September 30, 2013, to reduce the carrying value of the New AER disposal group to its estimated fair value less cost to sell. | |||||
[2] | Includes a noncash pretax asset impairment charge of $628 million to reduce the carrying value of AERG’s Duck Creek energy center to its estimated fair value under held and used accounting guidance. |
Divestiture_Transactions_and_D4
Divestiture Transactions and Discontinued Operations (Components of Assets and Liabilities) (Details) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2012 | ||
In Millions, unless otherwise specified | |||||
Assets of discontinued operations | ' | ' | ' | ||
Cash and cash equivalents | $25 | $25 | $25 | ||
Accounts receivable and unbilled revenue | 102 | 102 | ' | ||
Materials and supplies | 121 | 134 | ' | ||
Mark-to-market derivative assets | 71 | 102 | ' | ||
Property and plant, net | 623 | 748 | ' | ||
Accumulated deferred income taxes, net | 357 | 385 | ' | ||
Other assets | 96 | 104 | ' | ||
Total assets of discontinued operations | 1,395 | 1,600 | ' | ||
Liabilities of discontinued operations | ' | ' | ' | ||
Accounts payable and other current obligations | 141 | 133 | ' | ||
Mark-to-market derivative liabilities | 38 | 63 | ' | ||
Long-term debt, net | 824 | 824 | ' | ||
Asset retirement obligations | 87 | 78 | ' | ||
Pension and other postretirement benefits | 32 | 40 | ' | ||
Other liabilities | 19 | 28 | ' | ||
Total liabilities of discontinued operations | 1,141 | 1,166 | ' | ||
Accumulated other comprehensive gain (loss) | 3 | [1] | 19 | [1] | ' |
Noncontrolling Interest | $8 | [2] | $8 | [2] | ' |
Electric Energy, Inc | ' | ' | ' | ||
Liabilities of discontinued operations | ' | ' | ' | ||
Percentage of EEI not owned by Ameren | 20.00% | 20.00% | ' | ||
[1] | Accumulated other comprehensive income related to discontinued operations remains in “Accumulated other comprehensive loss†on Ameren’s September 30, 2013, and December 31, 2012, balance sheets. This balance relates to New AER assets and liabilities that will be realized or removed from Ameren’s balance sheet either before or at the closing of the New AER divestiture. | ||||
[2] | The 20% ownership interest of EEI not owned by Ameren was included in “Noncontrolling interests†on Ameren’s September 30, 2013, and December 31, 2012, balance sheets. This noncontrolling interest will be removed from Ameren’s balance sheet at the closing of the New AER divestiture. |
Divestiture_Transactions_and_D5
Divestiture Transactions and Discontinued Operations (Debt Ratios) (Details) | 9 Months Ended | |
Sep. 30, 2013 | ||
Restricted Payments [Member] | ' | |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | ' | |
Interest coverage ratio | 1.05 | [1] |
Restricted Payments [Member] | Minimum | ' | |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | ' | |
Interest coverage ratio | 1.75 | [1] |
Actual Ratio [Member] | ' | |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | ' | |
Interest coverage ratio | 1.05 | [2] |
Additional indebtedness debt-to-capital ratio, Actual | 0.51 | [2] |
Additional Indebtedness [Member] | Minimum | ' | |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | ' | |
Interest coverage ratio | 2.5 | [2] |
Maximum Leverage Ratio [Member] | ' | |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | ' | |
Additional indebtedness debt-to-capital ratio, Actual | 0.6 | [2] |
[1] | As of the date of the restricted payment, as defined, the minimum ratio must have been achieved for the most recently ended four fiscal quarters and projected by management to be achieved for each of the subsequent four six-month periods. Investments in the non-state-regulated subsidiary money pool and repayments of non-state-regulated subsidiary money pool borrowings are not subject to this incurrence test. | |
[2] | Ratios must be computed on a pro forma basis considering the additional indebtedness to be incurred and the related interest expense. Non-state-regulated subsidiary money pool borrowings are defined as permitted indebtedness and are not subject to these incurrence tests. Other borrowings from third-party external sources are included in the definition of indebtedness and are subject to these incurrence tests. |
Rate_And_Regulatory_Matters_Na
Rate And Regulatory Matters (Narrative-Missouri) (Detail) (USD $) | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 1 Months Ended | 3 Months Ended | |||||||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Jul. 31, 2011 | Dec. 30, 2012 | Jul. 31, 2013 | Jun. 30, 2013 | Sep. 30, 2013 |
Union Electric Company | Union Electric Company | Union Electric Company | Union Electric Company | Union Electric Company | Electric Distribution [Member] | Fac Prudence Review [Member] | Fac Prudence Review [Member] | Fac Prudence Review [Member] | |||||
Accounting Authority Order Request [Member] | Union Electric Company | Subsequent Periods After September 30, 2009 [Member] | Subsequent Periods After September 30, 2009 [Member] | Subsequent Periods After September 30, 2009 [Member] | |||||||||
Final Rate Order [Member] | MoPSC order [Member] | Union Electric Company | Union Electric Company | ||||||||||
Rate And Regulatory Matters [Line Items] | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Contested amounts under the FAC | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | $26 | $23 | $3 |
Interest Charges | 88 | 99 | 289 | 295 | 43 | 55 | 159 | 167 | ' | ' | 1 | 1 | ' |
Request to defer fixed costs not recovered from Noranda, amount | ' | ' | ' | ' | ' | ' | ' | ' | 36 | ' | ' | ' | ' |
Authorized Increase in Revenue from Utility Service | ' | ' | ' | ' | ' | ' | ' | ' | ' | $260 | ' | ' | ' |
Rate_And_Regulatory_Matters_Na1
Rate And Regulatory Matters (Narrative-Illinois) (Detail) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 | Dec. 31, 2012 | Sep. 30, 2013 | Oct. 11, 2013 | Jul. 31, 2013 | Oct. 11, 2013 | Sep. 20, 2013 | Oct. 11, 2013 | Oct. 11, 2013 | Sep. 30, 2013 | Dec. 31, 2012 | Oct. 11, 2013 | Oct. 11, 2013 | Sep. 30, 2013 |
Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company | ATXI [Member] | Ameren Illinois Company Position [Member] | Ameren Illinois Company Position [Member] | Icc Staff Recommendation [Member] | Icc Staff Recommendation [Member] | Increase in recoverable costs [Member] | Increase in recoverable costs [Member] | Revenue Requirement Reconcilation Adjustment [Member] | Revenue Requirement Reconcilation Adjustment [Member] | Revenue Requirement Reconcilation Adjustment [Member] | Revenue Requirement Reconcilation Adjustment [Member] | Pending Rate Case [Member] | |
Electric Distribution [Member] | Electric Distribution [Member] | Electric Distribution [Member] | Potential Transmission Project Investments Through2019 [Member] | Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company Position [Member] | Icc Staff Recommendation [Member] | Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company Position [Member] | Icc Staff Recommendation [Member] | Ameren Illinois Company | |
Final Rate Order [Member] | Rate order appeal [Member] | Electric Distribution [Member] | Gas Distribution [Member] | Electric Distribution [Member] | Gas Distribution [Member] | Ieima [Member] | Ieima [Member] | Electric Distribution [Member] | Electric Distribution [Member] | Ameren Illinois Company | Ieima [Member] | ||||
Subsequent Event [Member] | Pending Rate Case [Member] | Subsequent Event [Member] | Pending Rate Case [Member] | Ameren Illinois Company | Ameren Illinois Company | Electric Distribution [Member] | Ameren Illinois Company | ||||||||
Electric Distribution [Member] | Electric Distribution [Member] | Subsequent Event [Member] | Electric Distribution [Member] | ||||||||||||
Subsequent Event [Member] | Subsequent Event [Member] | Subsequent Event [Member] | |||||||||||||
Rate And Regulatory Matters [Line Items] | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Regulatory Assets | $59,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Revenue requirement | ' | 765,000,000 | ' | ' | 798,000,000 | ' | 789,000,000 | ' | ' | ' | ' | ' | ' | ' | ' |
Requested rate decrease, amount | ' | ' | 11,000,000 | ' | -22,000,000 | 47,000,000 | -42,000,000 | 28,000,000 | 33,000,000 | 24,000,000 | ' | ' | -55,000,000 | -66,000,000 | ' |
Rate Of Return On Common Equity | ' | ' | ' | ' | ' | 10.40% | ' | 8.80% | ' | ' | ' | ' | ' | ' | ' |
Percent Of Capital Structure Composed Of Equity | ' | ' | ' | ' | ' | 51.80% | ' | 50.40% | ' | ' | ' | ' | ' | ' | ' |
Rate Base | ' | ' | ' | ' | ' | 1,100,000,000 | ' | 1,100,000,000 | ' | ' | ' | ' | ' | ' | ' |
Regulatory liability | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 59,000,000 | 55,000,000 | ' | ' | ' |
Amount of Regulatory Costs Not yet Approved | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 63,000,000 |
Investments in Power and Distribution Projects | ' | ' | ' | $1,100,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Rate_And_Regulatory_Matters_Na2
Rate And Regulatory Matters (Narrative-Federal) (Detail) (USD $) | 1 Months Ended | 9 Months Ended | 12 Months Ended | 1 Months Ended | |||||||||||||
Nov. 30, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Dec. 31, 2012 | Jan. 31, 2011 | Sep. 30, 2013 | |
design | design | Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company | Union Electric Company | Union Electric Company | Union Electric Company | Union Electric Company | Union Electric Company | Union Electric Company | Wholesale Distribution Rate Case [Member] | Wholesale Distribution Rate Case [Member] | Wholesale Distribution Rate Case [Member] | Wholesale Distribution Rate Case [Member] | ||
Pending Ferc Case [Member] | Pending Ferc Case [Member] | New Nuclear Energy Center COL [Member] | New Nuclear Energy Center COL [Member] | New Nuclear Energy Center COL [Member] | New Nuclear Energy Center COL [Member] | Ameren Illinois Company | Ameren Illinois Company | ||||||||||
Minimum | Maximum | Minimum | Minimum | Maximum | appraiser | ||||||||||||
Rate And Regulatory Matters [Line Items] | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Number of Customers, Reached Agreements | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 4 | ' |
Number of Wholesale Customers | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 9 | ' |
Number of Customers, Remaining on Agreements | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 5 | ' |
Current regulatory liabilities | ' | $149,000,000 | $100,000,000 | $88,000,000 | $82,000,000 | ' | ' | $61,000,000 | $18,000,000 | ' | ' | ' | ' | $12,000,000 | $8,000,000 | ' | $9,000,000 |
Range of possible loss, minimum | ' | ' | ' | ' | ' | 10,000,000 | 15,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Department of Energy, Investing Funding Support, Number of Small Modular Reactor Designs | ' | 2 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Department of Energy, Investing Funding Support, Period | ' | '5 years | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Department of Energy, Investing Funding Support, Number of Small Modular Reactor Designs Awarded | 1 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Number of years an COL is valid for | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | '40 years | ' | ' | ' | ' | ' | ' |
Investments in Power and Distribution Projects | ' | ' | ' | ' | ' | ' | ' | ' | ' | $69,000,000 | ' | $80,000,000 | $100,000,000 | ' | ' | ' | ' |
ShortTerm_Debt_And_Liquidity_N
Short-Term Debt And Liquidity (Narrative) (Detail) (USD $) | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | ||||||||||
Sep. 30, 2013 | Sep. 30, 2012 | Dec. 31, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | |
Commercial Paper [Member] | Commercial Paper [Member] | Commercial Paper [Member] | Utilities [Member] | Utilities [Member] | Utilities [Member] | Utilities [Member] | Non State Regulated Subsidiaries [Member] | Non State Regulated Subsidiaries [Member] | Non State Regulated Subsidiaries [Member] | Non State Regulated Subsidiaries [Member] | Credit Agreements 2012 [Member] | Credit Agreements 2012 [Member] | Credit Agreements 2012 [Member] | Credit Agreements 2012 [Member] | |
Maximum | Union Electric Company | Ameren Illinois Company | |||||||||||||
Line of Credit Facility [Line Items] | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Line of credit facility, maximum borrowing capacity | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | $2,090,000,000 | ' | ' | ' |
Commercial paper outstanding | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Average daily commercial paper borrowings outstanding | 26,000,000 | 58,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Weighted average interest rate | 0.52% | 0.93% | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Peak short-term borrowings | $92,000,000 | $229,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Peak short-term borrowings interest rate | 0.85% | 1.25% | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Actual debt-to-capital ratio percentage | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 0.51 | 0.65 | 0.48 | 0.42 |
Minimum ratio of consolidated funds from operations plus interest expense to consolidated interest expense as of balance sheet date | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | '2.0 to 1 | ' | ' | ' |
Current ratio of consolidated funds from operations plus interest expense to consolidated interest expense as of balance sheet date | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | '5.1 to 1.0 | ' | ' | ' |
Short Term Debt, Weighted Average Interest Rate During Period | ' | ' | ' | 0.05% | 0.14% | 0.08% | 0.13% | 0.36% | 0.52% | 0.29% | 0.64% | ' | ' | ' | ' |
Line of Credit Facility, Covenant Terms, Ratio of Consolidated Operational Funds to Consolidated Interest Expense, Minimum | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 2 | ' | ' | ' |
Line of Credit Facility, Covenant Compliance, Ratio of Consolidated Operational Funds to Consolidated Interest Expense | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 5.1 | ' | ' | ' |
LongTerm_Debt_And_Equity_Finan2
Long-Term Debt And Equity Financings (Narrative) (Detail) (USD $) | 9 Months Ended | 6 Months Ended | 9 Months Ended | 1 Months Ended | |||||||
Sep. 30, 2013 | Sep. 30, 2012 | Jun. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2013 | Oct. 31, 2013 | Oct. 31, 2013 | |
Union Electric Company [Member] | Union Electric Company [Member] | Ameren Missouri And Ameren Illinois [Member] | Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company | Subsequent Event [Member] | Subsequent Event [Member] | |||
Federal Energy Regulatory Commission Restriction [Member] | Minimum | Environmental Improvement And Pollution Control Revenue Bonds [Member] | Secured Debt [Member] | ||||||||
Actual Ratio [Member] | Federal Energy Regulatory Commission Restriction [Member] | Series1993 Due2028 [Member] | Senior Secured Notes465 Due2013 [Member] | ||||||||
Union Electric Company [Member] | Union Electric Company [Member] | ||||||||||
Long-Term Debt And Equity Financings [Line Items] | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Repayments of Long-term Debt | ' | $754,000,000 | $0 | $422,000,000 | ' | ' | $332,000,000 | ' | ' | $44,000,000 | $200,000,000 |
Debt Instrument, Interest Rate, Stated Percentage | ' | ' | ' | ' | ' | ' | ' | ' | ' | 5.45% | 4.65% |
Assumed interest rate | ' | ' | ' | ' | 6.00% | ' | ' | ' | ' | ' | ' |
Dividend rate | ' | ' | ' | ' | 7.00% | ' | ' | ' | ' | ' | ' |
Excess in indebtedness upon default of maturity | $25,000,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Common stock equity to total capitalization | ' | ' | ' | ' | ' | ' | ' | 58.00% | 30.00% | ' | ' |
LongTerm_Debt_And_Equity_Finan3
Long-Term Debt And Equity Financings (Schedule Of Covered Ratio) (Detail) (USD $) | 9 Months Ended | |
In Millions, unless otherwise specified | Sep. 30, 2013 | |
Actual Ratio [Member] | ' | |
Debt Instrument [Line Items] | ' | |
Restricted payment interest coverage ratio, Actual | 1.05 | [1] |
Union Electric Company | ' | |
Debt Instrument [Line Items] | ' | |
Bonds Issuable | 3,564 | [2] |
Preferred Stock Issuable | 2,130 | |
Retired bond capacity | 485 | |
Union Electric Company | Actual Ratio [Member] | ' | |
Debt Instrument [Line Items] | ' | |
Restricted payment interest coverage ratio, Actual | 4.3 | |
Dividend Coverage Ratio | 111.5 | |
Ameren Illinois Company | ' | |
Debt Instrument [Line Items] | ' | |
Bonds Issuable | 3,536 | [2],[3] |
Preferred Stock Issuable | 203 | |
Retired bond capacity | 645 | |
Ameren Illinois Company | Actual Ratio [Member] | ' | |
Debt Instrument [Line Items] | ' | |
Restricted payment interest coverage ratio, Actual | 7.4 | |
Dividend Coverage Ratio | 2.7 | |
Minimum | Union Electric Company | Minimum Required Ratio [Member] | ' | |
Debt Instrument [Line Items] | ' | |
Restricted payment interest coverage ratio, Actual | 2 | [4] |
Dividend Coverage Ratio | 2.5 | [5] |
Minimum | Ameren Illinois Company | Minimum Required Ratio [Member] | ' | |
Debt Instrument [Line Items] | ' | |
Restricted payment interest coverage ratio, Actual | 2 | [4] |
Dividend Coverage Ratio | 1.5 | [5] |
[1] | Ratios must be computed on a pro forma basis considering the additional indebtedness to be incurred and the related interest expense. Non-state-regulated subsidiary money pool borrowings are defined as permitted indebtedness and are not subject to these incurrence tests. Other borrowings from third-party external sources are included in the definition of indebtedness and are subject to these incurrence tests. | |
[2] | Amount of bonds issuable based either on required coverage ratios or unfunded property additions, whichever is more restrictive. The amounts shown also include bonds issuable based on retired bond capacity of $485 million and $645 million at Ameren Missouri and Ameren Illinois, respectively. | |
[3] | Amount of bonds issuable by Ameren Illinois based on unfunded property additions and retired bonds solely under the former IP mortgage indenture. | |
[4] | Coverage required on the annual interest charges on first mortgage bonds outstanding and to be issued. Coverage is not required in certain cases when additional first mortgage bonds are issued on the basis of retired bonds. | |
[5] | Coverage required on the annual dividend on preferred stock outstanding and to be issued, as required in the respective company’s articles of incorporation. |
Other_Income_and_Expenses_Deta
Other Income and Expenses (Detail) (USD $) | 3 Months Ended | 9 Months Ended | ||||||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | ||||
Other Nonoperating Income (Expense) [Line Items] | ' | ' | ' | ' | ||||
Allowance for equity funds used during construction | $10 | [1] | $9 | [1] | $26 | [1] | $26 | [1] |
Interest income on industrial development revenue bonds | 7 | [1] | 7 | [1] | 21 | [1] | 21 | [1] |
Interest and dividend income | 2 | [1] | 0 | [1] | 3 | [1] | 4 | [1] |
Other | 1 | [1] | 1 | [1] | 1 | [1] | 2 | [1] |
Total miscellaneous income | 20 | [1] | 17 | [1] | 51 | [1] | 53 | [1] |
Donations | 2 | [1] | 3 | [1] | 7 | [1] | 18 | [1],[2] |
Other | 3 | [1] | 3 | [1] | 11 | [1] | 10 | [1] |
Total miscellaneous expense | 5 | [1] | 6 | [1] | 18 | [1] | 28 | [1] |
Union Electric Company | ' | ' | ' | ' | ||||
Other Nonoperating Income (Expense) [Line Items] | ' | ' | ' | ' | ||||
Allowance for equity funds used during construction | 8 | 8 | 22 | 23 | ||||
Interest income on industrial development revenue bonds | 7 | 7 | 21 | 21 | ||||
Interest and dividend income | 1 | 0 | 1 | 4 | ||||
Total miscellaneous income | 16 | 15 | 44 | 48 | ||||
Donations | 0 | 2 | 3 | 7 | ||||
Other | 2 | 2 | 7 | 4 | ||||
Total miscellaneous expense | 2 | 4 | 10 | 11 | ||||
Ameren Illinois Company | ' | ' | ' | ' | ||||
Other Nonoperating Income (Expense) [Line Items] | ' | ' | ' | ' | ||||
Allowance for equity funds used during construction | 2 | 1 | 4 | 3 | ||||
Interest and dividend income | 1 | 0 | 2 | 0 | ||||
Other | 1 | 1 | 1 | 2 | ||||
Total miscellaneous income | 4 | 2 | 7 | 5 | ||||
Donations | 0 | 1 | 3 | 11 | [2] | |||
Other | 3 | 1 | 4 | 4 | ||||
Total miscellaneous expense | 3 | 2 | 7 | 15 | ||||
Ameren Illinois Company | One-Time Donation [Member] | Illinois Science And Energy Innovation Trust [Member] | ' | ' | ' | ' | ||||
Other Nonoperating Income (Expense) [Line Items] | ' | ' | ' | ' | ||||
Donations | ' | ' | ' | $7.50 | ||||
[1] | Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations. | |||||||
[2] | Includes Ameren Illinois’ one-time $7.5 million contribution to the Illinois Science and Energy Innovation Trust pursuant to the IEIMA as a result of Ameren Illinois’ 2012 election to participate in the formula ratemaking process. |
Derivative_Financial_Instrumen3
Derivative Financial Instruments (Open Gross Derivative Volumes By Commodity Type) (Detail) | Sep. 30, 2013 | Dec. 31, 2012 | ||
gal | gal | |||
Derivative That Qualify for Regulatory Deferral | Fuel Oils | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 60,000,000 | [1],[2] | 70,000,000 | [1],[2] |
Derivative That Qualify for Regulatory Deferral | Natural Gas | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 144,000,000 | [1] | 147,000,000 | [1] |
Derivative That Qualify for Regulatory Deferral | Power | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 16,000,000 | [1] | 23,000,000 | [1] |
Derivative That Qualify for Regulatory Deferral | Uranium | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 996,000 | [1] | 446,000 | [1] |
Derivative That Qualify for Regulatory Deferral | Union Electric Company | Natural Gas | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 29,000,000 | [1] | 19,000,000 | [1] |
Derivative That Qualify for Regulatory Deferral | Union Electric Company | Power | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 5,000,000 | [1] | 9,000,000 | [1] |
Derivative That Qualify for Regulatory Deferral | Ameren Illinois Company | Natural Gas | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 115,000,000 | [1] | 128,000,000 | [1] |
Derivative That Qualify for Regulatory Deferral | Ameren Illinois Company | Power | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 11,000,000 | [1] | 14,000,000 | [1] |
Other Contract | Natural Gas | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | ' | ' | ||
Other Contract | Power | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 1,000,000 | [3] | 2,000,000 | [3] |
Other Contract | Union Electric Company | Natural Gas | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | ' | ' | ||
Other Contract | Union Electric Company | Power | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 1,000,000 | [3] | 2,000,000 | [3] |
Accrual and Normal Purchases and Normal Sales Contracts | Coal | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 81,000,000 | [4] | 96,000,000 | [4] |
Accrual and Normal Purchases and Normal Sales Contracts | Natural Gas | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 8,000,000 | [4] | 20,000,000 | [4] |
Accrual and Normal Purchases and Normal Sales Contracts | Power | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 18,000,000 | [4] | 24,000,000 | [4] |
Accrual and Normal Purchases and Normal Sales Contracts | Renewable Energy Credits [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 14,000,000 | [4],[5] | 15,000,000 | [4],[5] |
Accrual and Normal Purchases and Normal Sales Contracts | Uranium | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 4,516,000 | [4] | 5,142,000 | [4] |
Accrual and Normal Purchases and Normal Sales Contracts | Union Electric Company | Natural Gas | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 2,000,000 | [4] | 4,000,000 | [4] |
Accrual and Normal Purchases and Normal Sales Contracts | Union Electric Company | Power | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 3,000,000 | [4] | 3,000,000 | [4] |
Accrual and Normal Purchases and Normal Sales Contracts | Union Electric Company | Renewable Energy Credits [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 3,000,000 | [4],[5] | 3,000,000 | [4],[5] |
Accrual and Normal Purchases and Normal Sales Contracts | Ameren Illinois Company | Natural Gas | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 6,000,000 | [4] | 16,000,000 | [4] |
Accrual and Normal Purchases and Normal Sales Contracts | Ameren Illinois Company | Power | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 15,000,000 | [4] | 21,000,000 | [4] |
Accrual and Normal Purchases and Normal Sales Contracts | Ameren Illinois Company | Renewable Energy Credits [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Accrual & NPNS Contracts | 11,000,000 | [4],[5] | 12,000,000 | [4],[5] |
[1] | As of September 30, 2013, these contracts ran through October 2015, October 2019, May 2032, and October 2016 for fuel oils, natural gas, power, and uranium, respectively. | |||
[2] | Fuel oils consist of heating oil, ultra-low sulfur diesel, and crude oil. | |||
[3] | As of September 30, 2013, these contracts ran through December 2014 for power. | |||
[4] | Accrual contracts include commodity contracts that do not qualify as derivatives. As of September 30, 2013, these contracts ran through December 2017, March 2015, September 2024, May 2032, and October 2024 for coal, natural gas, power, renewable energy credits, and uranium, respectively. | |||
[5] | A renewable energy credit is created for every one megawatthour of renewable energy generated. The Ameren Companies’ contracts include renewable energy credits from solar and wind-generated power. |
Derivative_Financial_Instrumen4
Derivative Financial Instruments (Derivative Instruments Carrying Value) (Detail) (Not Designated As Hedging Instrument [Member], USD $) | Sep. 30, 2013 | Dec. 31, 2012 | ||
In Millions, unless otherwise specified | ||||
Derivative [Line Items] | ' | ' | ||
Derivative assets | $41 | [1] | $29 | [1] |
Derivative liabilities | 182 | [1] | 230 | [1] |
Fuel Oils | Other Current Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 6 | [1] | 8 | [1] |
Fuel Oils | Other Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 2 | [1] | 4 | [1] |
Fuel Oils | Mark To Market Derivative Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 3 | [1] | 2 | [1] |
Fuel Oils | Other Deferred Credits And Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 1 | [1] | 2 | [1] |
Natural Gas | Other Current Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 1 | [1] | 1 | [1] |
Natural Gas | Other Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | ' | 1 | [1] | |
Natural Gas | Mark To Market Derivative Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 45 | [1] | 64 | [1] |
Natural Gas | Other Deferred Credits And Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 30 | [1] | 45 | [1] |
Power | Other Current Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 30 | [1] | 14 | [1] |
Power | Other Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 1 | [1] | 1 | [1] |
Power | Mark To Market Derivative Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 13 | [1] | 25 | [1] |
Power | Other Deferred Credits And Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 84 | [1] | 90 | [1] |
Uranium | Other Current Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 1 | [1] | ' | |
Uranium | Mark To Market Derivative Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 4 | [1] | 1 | [1] |
Uranium | Other Deferred Credits And Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 2 | 1 | [1] | |
Union Electric Company | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 41 | [1] | 28 | [1] |
Derivative liabilities | 26 | [1] | 25 | [1] |
Union Electric Company | Fuel Oils | Other Current Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 6 | [1] | 8 | [1] |
Union Electric Company | Fuel Oils | Other Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 2 | [1] | 4 | [1] |
Union Electric Company | Fuel Oils | Other Current Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 3 | [1] | 2 | [1] |
Union Electric Company | Fuel Oils | Other Deferred Credits And Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 1 | [1] | 2 | [1] |
Union Electric Company | Natural Gas | Other Current Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 1 | [1] | ' | |
Union Electric Company | Natural Gas | Other Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | ' | 1 | [1] | |
Union Electric Company | Natural Gas | Other Current Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 7 | [1] | 8 | [1] |
Union Electric Company | Natural Gas | Other Deferred Credits And Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 6 | [1] | 7 | [1] |
Union Electric Company | Power | Other Current Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 30 | [1] | 14 | [1] |
Union Electric Company | Power | Other Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 1 | [1] | 1 | [1] |
Union Electric Company | Power | Other Current Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 3 | [1] | 4 | [1] |
Union Electric Company | Uranium | Other Current Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | 1 | [1] | ' | |
Union Electric Company | Uranium | Other Current Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 4 | [1] | 1 | [1] |
Union Electric Company | Uranium | Other Deferred Credits And Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 2 | 1 | [1] | |
Ameren Illinois Company | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | ' | 1 | [1] | |
Derivative liabilities | 156 | [1] | 205 | [1] |
Ameren Illinois Company | Natural Gas | Other Current Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative assets | ' | 1 | [1] | |
Ameren Illinois Company | Natural Gas | Mark To Market Derivative Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 38 | [1] | 56 | [1] |
Ameren Illinois Company | Natural Gas | Other Deferred Credits And Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 24 | [1] | 38 | [1] |
Ameren Illinois Company | Power | Mark To Market Derivative Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | 10 | [1] | 21 | [1] |
Ameren Illinois Company | Power | Other Deferred Credits And Liabilities [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Derivative liabilities | $84 | [1] | $90 | [1] |
[1] | Includes derivatives subject to regulatory deferral. |
Derivative_Financial_Instrumen5
Derivative Financial Instruments (Cumulative Amount Of Pretax Net Gains (Losses) On All Derivative Instruments In OCI) (Detail) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 | ||
In Millions, unless otherwise specified | ||||
Derivative [Line Items] | ' | ' | ||
Current gains deferred as regulatory liabilities | $149 | $100 | ||
Current losses deferred as regulatory assets | 173 | 247 | ||
Fuel Oils | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Current gains deferred as regulatory liabilities | 3 | ' | ||
Current losses deferred as regulatory assets | 1 | ' | ||
Fuel Oils | Regulatory Liabilities Or Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Cumulative deferred pretax gains (losses) | 1 | [1] | 4 | [1] |
Natural Gas | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Current gains deferred as regulatory liabilities | 1 | ' | ||
Current losses deferred as regulatory assets | 45 | ' | ||
Natural Gas | Regulatory Liabilities Or Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Cumulative deferred pretax gains (losses) | -74 | [2] | -107 | [2] |
Power | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Current gains deferred as regulatory liabilities | 29 | ' | ||
Current losses deferred as regulatory assets | 13 | ' | ||
Power | Regulatory Liabilities Or Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Cumulative deferred pretax gains (losses) | -67 | [3] | -99 | [3] |
Uranium | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Current gains deferred as regulatory liabilities | 1 | ' | ||
Current losses deferred as regulatory assets | 4 | ' | ||
Uranium | Regulatory Liabilities Or Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Cumulative deferred pretax gains (losses) | -5 | [4] | -2 | [4] |
Union Electric Company | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Current gains deferred as regulatory liabilities | 61 | 18 | ||
Current losses deferred as regulatory assets | 124 | 163 | ||
Union Electric Company | Fuel Oils | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Current gains deferred as regulatory liabilities | 3 | ' | ||
Current losses deferred as regulatory assets | 1 | ' | ||
Union Electric Company | Fuel Oils | Regulatory Liabilities Or Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Cumulative deferred pretax gains (losses) | 1 | [1] | 4 | [1] |
Union Electric Company | Natural Gas | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Current gains deferred as regulatory liabilities | 1 | ' | ||
Current losses deferred as regulatory assets | 7 | ' | ||
Union Electric Company | Natural Gas | Regulatory Liabilities Or Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Cumulative deferred pretax gains (losses) | -12 | [2] | -14 | [2] |
Union Electric Company | Power | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Current gains deferred as regulatory liabilities | 29 | ' | ||
Current losses deferred as regulatory assets | 3 | ' | ||
Union Electric Company | Power | Regulatory Liabilities Or Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Cumulative deferred pretax gains (losses) | 27 | [3] | 12 | [3] |
Union Electric Company | Uranium | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Current gains deferred as regulatory liabilities | 1 | ' | ||
Current losses deferred as regulatory assets | 4 | ' | ||
Union Electric Company | Uranium | Regulatory Liabilities Or Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Cumulative deferred pretax gains (losses) | -5 | [4] | -2 | [4] |
Ameren Illinois Company | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Current gains deferred as regulatory liabilities | 88 | 82 | ||
Current losses deferred as regulatory assets | 49 | 84 | ||
Ameren Illinois Company | Natural Gas | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Current losses deferred as regulatory assets | 38 | ' | ||
Ameren Illinois Company | Natural Gas | Regulatory Liabilities Or Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Cumulative deferred pretax gains (losses) | -62 | [2] | -93 | [2] |
Ameren Illinois Company | Power | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Current losses deferred as regulatory assets | 10 | ' | ||
Ameren Illinois Company | Power | Regulatory Liabilities Or Assets [Member] | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Cumulative deferred pretax gains (losses) | ($94) | [3] | ($111) | [3] |
[1] | Represents net gains (losses) on fuel oils derivative contracts at Ameren Missouri. These contracts are a partial hedge of Ameren Missouri’s transportation costs for coal through October 2015 as of September 30, 2013. Current gains deferred as regulatory liabilities include $3 million and $3 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. Current losses deferred as regulatory assets include $1 million and $1 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013 | |||
[2] | Represents net losses associated with natural gas derivative contracts. These contracts are a partial hedge of natural gas requirements through October 2019 at Ameren and Ameren Missouri and through March 2017 at Ameren Illinois as of September 30, 2013. Current gains deferred as regulatory liabilities include $1 million, and $1 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. Current losses deferred as regulatory assets include $45 million, $7 million, and $38 million at Ameren, Ameren Missouri and Ameren Illinois, respectively, as of September 30, 2013. | |||
[3] | Represents net gains (losses) associated with power derivative contracts. These contracts are a partial hedge of power price requirements through May 2032 at Ameren and Ameren Illinois and through December 2015 at Ameren Missouri as of September 30, 2013. Current gains deferred as regulatory liabilities include $29 million and $29 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. Current losses deferred as regulatory assets include $13 million, $3 million, and $10 million at Ameren, Ameren Missouri and Ameren Illinois, respectively, as of September 30, 2013. | |||
[4] | Represents net losses on uranium derivative contracts at Ameren Missouri. These contracts are a partial hedge of Ameren Missouri’s uranium requirements through October 2016 as of September 30, 2013. Current gains deferred as regulatory liabilities included $1 million and $1 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. Current losses deferred as regulatory assets include $4 million and $4 million at Ameren and Ameren Missouri, respectively, as of September 30, 2013. |
Derivative_Financial_Instrumen6
Derivative Financial Instruments (Offsetting Derivative Assets and Liabilities) (Details) (Commodity Contract, USD $) | Sep. 30, 2013 | Dec. 31, 2012 | ||
In Millions, unless otherwise specified | ||||
Offsetting Assets and Liabilities [Line Items] | ' | ' | ||
Gross Amounts Recognized in the Balance Sheet | $41 | [1] | $29 | [1] |
Derivative Instruments | 11 | 10 | ||
Cash Collateral Received/Posted | ' | [2] | ' | [2] |
Net Amount | 30 | 19 | ||
Gross Amounts Recognized in the Balance Sheet | 182 | [1] | 230 | [1] |
Derivative Instruments | 11 | 10 | ||
Cash Collateral Received/Posted | 32 | [2] | 65 | [2] |
Net Amount | 139 | 155 | ||
Union Electric Company | ' | ' | ||
Offsetting Assets and Liabilities [Line Items] | ' | ' | ||
Gross Amounts Recognized in the Balance Sheet | 41 | [1] | 28 | [1] |
Derivative Instruments | 11 | 9 | ||
Cash Collateral Received/Posted | ' | [2] | ' | [2] |
Net Amount | 30 | 19 | ||
Gross Amounts Recognized in the Balance Sheet | 26 | [1] | 25 | [1] |
Derivative Instruments | 11 | 9 | ||
Cash Collateral Received/Posted | 8 | [2] | 7 | [2] |
Net Amount | 7 | 9 | ||
Ameren Illinois Company | ' | ' | ||
Offsetting Assets and Liabilities [Line Items] | ' | ' | ||
Gross Amounts Recognized in the Balance Sheet | ' | 1 | ||
Derivative Instruments | ' | 1 | ||
Cash Collateral Received/Posted | ' | [2] | ' | [2] |
Net Amount | ' | ' | ||
Gross Amounts Recognized in the Balance Sheet | 156 | [1] | 205 | [1] |
Derivative Instruments | ' | 1 | ||
Cash Collateral Received/Posted | 24 | [2] | 58 | [2] |
Net Amount | $132 | $146 | ||
[1] | The derivative asset and liability balances are presented net of counterparty credit considerations. | |||
[2] | Cash collateral received reduces gross asset balances and is included in “Other current liabilities†and “Other deferred credits and liabilities†on the balance sheet. Cash collateral posted reduces gross liability balances and is included in “Other current assets†and “Other assets†on the balance sheet. |
Derivative_Financial_Instrumen7
Derivative Financial Instruments (Maximum Exposure If Counterparties Fail To Perform On Contracts) (Detail) (USD $) | 9 Months Ended | 12 Months Ended |
In Millions, unless otherwise specified | Sep. 30, 2013 | Dec. 31, 2012 |
Derivative [Line Items] | ' | ' |
Maximum exposure to counterparties related to derivative contracts | $11 | $23 |
Union Electric Company | ' | ' |
Derivative [Line Items] | ' | ' |
Maximum exposure to counterparties related to derivative contracts | 11 | 22 |
Ameren Illinois Company | ' | ' |
Derivative [Line Items] | ' | ' |
Maximum exposure to counterparties related to derivative contracts | ' | 1 |
Commodity Marketing Companies [Member] | ' | ' |
Derivative [Line Items] | ' | ' |
Maximum exposure to counterparties related to derivative contracts | 1 | 2 |
Commodity Marketing Companies [Member] | Union Electric Company | ' | ' |
Derivative [Line Items] | ' | ' |
Maximum exposure to counterparties related to derivative contracts | 1 | 2 |
Electric Utilities [Member] | ' | ' |
Derivative [Line Items] | ' | ' |
Maximum exposure to counterparties related to derivative contracts | 1 | 3 |
Electric Utilities [Member] | Union Electric Company | ' | ' |
Derivative [Line Items] | ' | ' |
Maximum exposure to counterparties related to derivative contracts | 1 | 3 |
Financial Companies [Member] | ' | ' |
Derivative [Line Items] | ' | ' |
Maximum exposure to counterparties related to derivative contracts | 7 | 15 |
Financial Companies [Member] | Union Electric Company | ' | ' |
Derivative [Line Items] | ' | ' |
Maximum exposure to counterparties related to derivative contracts | 7 | 14 |
Financial Companies [Member] | Ameren Illinois Company | ' | ' |
Derivative [Line Items] | ' | ' |
Maximum exposure to counterparties related to derivative contracts | ' | 1 |
Municipalities/Cooperatives [Member] | ' | ' |
Derivative [Line Items] | ' | ' |
Maximum exposure to counterparties related to derivative contracts | 2 | 3 |
Municipalities/Cooperatives [Member] | Union Electric Company | ' | ' |
Derivative [Line Items] | ' | ' |
Maximum exposure to counterparties related to derivative contracts | $2 | $3 |
Derivative_Financial_Instrumen8
Derivative Financial Instruments (Narrative) (Detail) (Union Electric Company, USD $) | Dec. 31, 2012 |
In Millions, unless otherwise specified | |
Union Electric Company | ' |
Derivative [Line Items] | ' |
Counterparty letters of credit held as collateral | $1 |
Derivative_Financial_Instrumen9
Derivative Financial Instruments (Potential Loss On Counterparty Exposures) (Detail) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 |
In Millions, unless otherwise specified | ||
Concentration Risk [Line Items] | ' | ' |
Potential loss on counterparty exposures related to derivative contracts | $5 | $15 |
Union Electric Company | ' | ' |
Concentration Risk [Line Items] | ' | ' |
Potential loss on counterparty exposures related to derivative contracts | 5 | 15 |
Commodity Marketing Companies [Member] | ' | ' |
Concentration Risk [Line Items] | ' | ' |
Potential loss on counterparty exposures related to derivative contracts | 1 | 1 |
Commodity Marketing Companies [Member] | Union Electric Company | ' | ' |
Concentration Risk [Line Items] | ' | ' |
Potential loss on counterparty exposures related to derivative contracts | 1 | 1 |
Electric Utilities [Member] | ' | ' |
Concentration Risk [Line Items] | ' | ' |
Potential loss on counterparty exposures related to derivative contracts | ' | 1 |
Electric Utilities [Member] | Union Electric Company | ' | ' |
Concentration Risk [Line Items] | ' | ' |
Potential loss on counterparty exposures related to derivative contracts | ' | 1 |
Financial Companies [Member] | ' | ' |
Concentration Risk [Line Items] | ' | ' |
Potential loss on counterparty exposures related to derivative contracts | 2 | 10 |
Financial Companies [Member] | Union Electric Company | ' | ' |
Concentration Risk [Line Items] | ' | ' |
Potential loss on counterparty exposures related to derivative contracts | 2 | 10 |
Municipalities/Cooperatives [Member] | ' | ' |
Concentration Risk [Line Items] | ' | ' |
Potential loss on counterparty exposures related to derivative contracts | 2 | 3 |
Municipalities/Cooperatives [Member] | Union Electric Company | ' | ' |
Concentration Risk [Line Items] | ' | ' |
Potential loss on counterparty exposures related to derivative contracts | $2 | $3 |
Recovered_Sheet1
Derivative Financial Instruments (Derivative Instruments With Credit Risk-Related Contingent Features) (Detail) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 | ||
In Millions, unless otherwise specified | ||||
Derivative [Line Items] | ' | ' | ||
Aggregate Fair Value of Derivative Liabilities | $170 | [1] | $226 | [1] |
Cash Collateral Posted | 25 | 61 | ||
Potential Aggregate Amount of Additional Collateral Required | 133 | [2] | 155 | [2] |
Union Electric Company | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Aggregate Fair Value of Derivative Liabilities | 69 | [1] | 78 | [1] |
Cash Collateral Posted | 1 | 3 | ||
Potential Aggregate Amount of Additional Collateral Required | 63 | [2] | 71 | [2] |
Ameren Illinois Company | ' | ' | ||
Derivative [Line Items] | ' | ' | ||
Aggregate Fair Value of Derivative Liabilities | 101 | [1] | 148 | [1] |
Cash Collateral Posted | 24 | 58 | ||
Potential Aggregate Amount of Additional Collateral Required | $70 | [2] | $84 | [2] |
[1] | Prior to consideration of master trading and netting agreements and including NPNS contract exposures. | |||
[2] | As collateral requirements with certain counterparties are based on master trading and netting agreements, the aggregate amount of additional collateral required to be posted is determined after consideration of the netting effects of such agreements. |
Recovered_Sheet2
Derivative Financial Instruments (Derivatives That Qualify For Regulatory Deferral) (Detail) (USD $) | 3 Months Ended | 9 Months Ended | ||||||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | ($16) | $44 | $59 | ($105) | ||||
Union Electric Company | ' | ' | ' | ' | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | -11 | 4 | 11 | -4 | ||||
Ameren Illinois Company | ' | ' | ' | ' | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | -5 | 96 | 48 | 40 | ||||
Fuel Oils | ' | ' | ' | ' | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | 1 | 5 | -3 | -9 | ||||
Fuel Oils | Union Electric Company | ' | ' | ' | ' | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | 1 | 5 | -3 | -9 | ||||
Natural Gas | ' | ' | ' | ' | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | 9 | 46 | 33 | 74 | ||||
Natural Gas | Union Electric Company | ' | ' | ' | ' | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | ' | 6 | 2 | 9 | ||||
Natural Gas | Ameren Illinois Company | ' | ' | ' | ' | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | 9 | 40 | 31 | 65 | ||||
Power | ' | ' | ' | ' | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | -24 | [1] | -6 | [1] | 32 | [1] | -169 | [1] |
Power | Union Electric Company | ' | ' | ' | ' | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | -10 | -6 | 15 | -3 | ||||
Power | Ameren Illinois Company | ' | ' | ' | ' | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | -14 | 56 | 17 | -25 | ||||
Uranium | ' | ' | ' | ' | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | -2 | -1 | -3 | -1 | ||||
Uranium | Union Electric Company | ' | ' | ' | ' | ||||
Derivative [Line Items] | ' | ' | ' | ' | ||||
Net change in market value of derivatives that qualify for regulatory deferral | ($2) | ($1) | ($3) | ($1) | ||||
[1] | Amounts include intercompany eliminations. |
Fair_Value_Measurements_Schedu
Fair Value Measurements (Schedule Of Valuation Process And Unobservable Inputs) (Detail) (USD $) | 9 Months Ended | 12 Months Ended | ||
In Millions, unless otherwise specified | Sep. 30, 2013 | Dec. 31, 2012 | ||
Natural Gas | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative assets | 1 | [1] | ' | |
Natural Gas | Discounted Cash Flow | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Counterparty credit risk | 0.64% | [2],[3] | ' | |
Nodal basis | -0.1 | [3] | ' | |
Credit risk | 2.00% | [2],[3] | ' | |
Natural Gas | Discounted Cash Flow | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Counterparty credit risk | 0.83% | [2],[3] | ' | |
Credit risk | 3.00% | [2],[3] | ' | |
Natural Gas | Discounted Cash Flow | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Counterparty credit risk | 0.77% | [2],[3] | ' | |
Credit risk | 2.00% | [2],[3] | ' | |
Natural Gas | Option Model | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Volatilities | 5.00% | [4] | ' | |
Nodal basis | -0.4 | [3] | ' | |
Natural Gas | Option Model | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Volatilities | 29.00% | [4] | ' | |
Nodal basis | -0.2 | [3] | ' | |
Natural Gas | Option Model | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Volatilities | 24.00% | [4] | ' | |
Nodal basis | -0.4 | [3] | ' | |
Natural Gas | Union Electric Company | Discounted Cash Flow | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Counterparty credit risk | 0.64% | [2],[3] | ' | |
Nodal basis | -0.1 | [3] | ' | |
Credit risk | 2.00% | [2],[3] | ' | |
Natural Gas | Union Electric Company | Discounted Cash Flow | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Counterparty credit risk | 0.83% | [2],[3] | ' | |
Credit risk | 3.00% | [2],[3] | ' | |
Natural Gas | Union Electric Company | Discounted Cash Flow | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Counterparty credit risk | 0.77% | [2],[3] | ' | |
Credit risk | 2.00% | [2],[3] | ' | |
Natural Gas | Union Electric Company | Option Model | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | ' | ' | ||
Volatilities | 5.00% | [4] | ' | |
Nodal basis | -0.4 | [3] | ' | |
Natural Gas | Union Electric Company | Option Model | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | ' | ' | ||
Volatilities | 29.00% | [4] | ' | |
Nodal basis | -0.2 | [3] | ' | |
Natural Gas | Union Electric Company | Option Model | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | ' | ' | ||
Volatilities | 24.00% | [4] | ' | |
Nodal basis | -0.4 | [3] | ' | |
Natural Gas | Union Electric Company | Derivative Assets | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative assets | 1 | [1] | ' | |
Natural Gas | Ameren Illinois Company | Derivative Assets | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative assets | ' | [1] | ' | |
Natural Gas | Derivative Liabilities | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative liabilities | -1 | [1] | ' | |
Natural Gas | Derivative Liabilities | Union Electric Company | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative liabilities | -1 | [1] | ' | |
Natural Gas | Derivative Liabilities | Ameren Illinois Company | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative liabilities | ' | [1] | ' | |
Fuel Oils | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative assets | 7 | [1] | 8 | [1] |
Fuel Oils | Discounted Cash Flow | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Credit risk | ' | 2.00% | [2],[3] | |
Fuel Oils | Discounted Cash Flow | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | ' | 0.21% | [4] | |
Counterparty credit risk | 0.26% | [2],[3] | 0.12% | [2],[3] |
Fuel Oils | Discounted Cash Flow | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | ' | 0.60% | [4] | |
Counterparty credit risk | 3.00% | [2],[3] | 1.00% | [2],[3] |
Fuel Oils | Discounted Cash Flow | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | ' | 0.44% | [4] | |
Counterparty credit risk | 2.00% | [2],[3] | 1.00% | [2],[3] |
Fuel Oils | Option Model | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Volatilities | 9.00% | [4] | 7.00% | [4] |
Fuel Oils | Option Model | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Volatilities | 20.00% | [4] | 27.00% | [4] |
Fuel Oils | Option Model | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Volatilities | 17.00% | [4] | 24.00% | [4] |
Fuel Oils | Union Electric Company | Discounted Cash Flow | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Credit risk | ' | 2.00% | [2],[3] | |
Fuel Oils | Union Electric Company | Discounted Cash Flow | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | ' | 0.21% | [4] | |
Counterparty credit risk | 0.26% | [2],[3] | 0.12% | [2],[3] |
Fuel Oils | Union Electric Company | Discounted Cash Flow | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | ' | 0.60% | [4] | |
Counterparty credit risk | 3.00% | [2],[3] | 1.00% | [2],[3] |
Fuel Oils | Union Electric Company | Discounted Cash Flow | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | ' | 0.44% | [4] | |
Counterparty credit risk | 2.00% | [2],[3] | 1.00% | [2],[3] |
Fuel Oils | Union Electric Company | Option Model | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Volatilities | 9.00% | [4] | 7.00% | [4] |
Fuel Oils | Union Electric Company | Option Model | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Volatilities | 20.00% | [4] | 27.00% | [4] |
Fuel Oils | Union Electric Company | Option Model | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Volatilities | 17.00% | [4] | 24.00% | [4] |
Fuel Oils | Union Electric Company | Derivative Assets | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative assets | 7 | [1] | 8 | [1] |
Fuel Oils | Derivative Liabilities | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative liabilities | -4 | [1] | -3 | [1] |
Fuel Oils | Derivative Liabilities | Union Electric Company | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative liabilities | -4 | [1] | -3 | [1] |
Power | Discounted Cash Flow | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Credit risk | 3.00% | [2],[3] | ' | |
Power | Discounted Cash Flow | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Counterparty credit risk | 0.22% | [2],[3] | 0.22% | [2],[3] |
Nodal basis | -5 | [3] | -5 | [3] |
Credit risk | ' | 2.00% | [2],[3] | |
Average bid/ask consensus peak and offpeak pricing | 27 | [3] | 22 | [3] |
Estimated auction price | -103 | [4] | -281 | [4] |
Power | Discounted Cash Flow | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Counterparty credit risk | 3.00% | [2],[3] | 1.00% | [2],[3] |
Nodal basis | -1 | [3] | -1 | [3] |
Credit risk | ' | 5.00% | [2],[3] | |
Average bid/ask consensus peak and offpeak pricing | 43 | [3] | 47 | [3] |
Estimated auction price | 1,790 | [4] | 1,851 | [4] |
Power | Discounted Cash Flow | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Counterparty credit risk | 0.73% | [2],[3] | 1.00% | [2],[3] |
Nodal basis | -3 | [3] | -3 | [3] |
Credit risk | ' | 5.00% | [2],[3] | |
Average bid/ask consensus peak and offpeak pricing | 30 | [3] | 31 | [3] |
Estimated auction price | 660 | [4] | 178 | [4] |
Power | Fundamental Energy Production Model | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | 4.00% | [4],[5] | ' | |
Estimated future gas prices | 4 | [4] | 4 | [4] |
Power | Fundamental Energy Production Model | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | 5.00% | [4],[5] | ' | |
Estimated future gas prices | 7 | [4] | 8 | [4] |
Power | Fundamental Energy Production Model | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | 4.00% | [4],[5] | ' | |
Estimated future gas prices | 5 | [4] | 6 | [4] |
Power | Contract Price Allocation | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Estimated renewable energy credit costs | 5 | [4] | 5 | [4] |
Power | Contract Price Allocation | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Estimated renewable energy credit costs | 7 | [4] | 7 | [4] |
Power | Contract Price Allocation | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Estimated renewable energy credit costs | 6 | [4] | 6 | [4] |
Power | Derivative Assets | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative assets | 29 | [1],[6] | 14 | [1],[6] |
Power | Union Electric Company | Discounted Cash Flow | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Credit risk | 3.00% | [2],[3] | 2.00% | [2],[3] |
Power | Union Electric Company | Discounted Cash Flow | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Counterparty credit risk | 0.22% | [2],[3] | 0.22% | [2],[3] |
Nodal basis | -4 | [3] | -5 | [3] |
Average bid/ask consensus peak and offpeak pricing | 27 | [3] | 24 | [3] |
Estimated auction price | -103 | [4] | -281 | [4] |
Power | Union Electric Company | Discounted Cash Flow | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Counterparty credit risk | 3.00% | [2],[3] | 1.00% | [2],[3] |
Nodal basis | -1 | [3] | -1 | [3] |
Average bid/ask consensus peak and offpeak pricing | 43 | [3] | 56 | [3] |
Estimated auction price | 1,790 | [4] | 1,851 | [4] |
Power | Union Electric Company | Discounted Cash Flow | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Counterparty credit risk | 0.73% | [2],[3] | 1.00% | [2],[3] |
Nodal basis | -4 | [3] | -2 | [3] |
Average bid/ask consensus peak and offpeak pricing | 33 | [3] | 36 | [3] |
Estimated auction price | 660 | [4] | 178 | [4] |
Power | Union Electric Company | Derivative Assets | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative assets | 29 | [1],[6] | 14 | [1],[6] |
Power | Ameren Illinois Company | Discounted Cash Flow | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Credit risk | 3.00% | [2],[3] | 5.00% | [2],[3] |
Power | Ameren Illinois Company | Discounted Cash Flow | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Nodal basis | -5 | [4] | -5 | [4] |
Average bid/ask consensus peak and offpeak pricing | 27 | [4] | 22 | [4] |
Power | Ameren Illinois Company | Discounted Cash Flow | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Nodal basis | -1 | [4] | -1 | [4] |
Average bid/ask consensus peak and offpeak pricing | 37 | [4] | 47 | [4] |
Power | Ameren Illinois Company | Discounted Cash Flow | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Nodal basis | -3 | [4] | -3 | [4] |
Average bid/ask consensus peak and offpeak pricing | 30 | [4] | 30 | [4] |
Power | Ameren Illinois Company | Fundamental Energy Production Model | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | 4.00% | [4],[5] | ' | |
Estimated future gas prices | 4 | [4] | 4 | [4] |
Power | Ameren Illinois Company | Fundamental Energy Production Model | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | 5.00% | [4],[5] | ' | |
Estimated future gas prices | 7 | [4] | 8 | [4] |
Power | Ameren Illinois Company | Fundamental Energy Production Model | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Escalation rate | 4.00% | [4],[5] | ' | |
Estimated future gas prices | 5 | [4] | 6 | [4] |
Power | Ameren Illinois Company | Contract Price Allocation | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Estimated renewable energy credit costs | 5 | [4] | 5 | [4] |
Power | Ameren Illinois Company | Contract Price Allocation | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Estimated renewable energy credit costs | 7 | [4] | 7 | [4] |
Power | Ameren Illinois Company | Contract Price Allocation | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Estimated renewable energy credit costs | 6 | [4] | 6 | [4] |
Power | Ameren Illinois Company | Derivative Assets | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative assets | ' | [1],[6] | ' | [1],[6] |
Power | Derivative Liabilities | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative liabilities | -95 | [1],[6] | -114 | [1],[6] |
Power | Derivative Liabilities | Union Electric Company | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative liabilities | -1 | [1],[6] | -3 | [1],[6] |
Power | Derivative Liabilities | Ameren Illinois Company | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative liabilities | -94 | [1],[6] | -111 | [1],[6] |
Uranium | Discounted Cash Flow | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Average bid/ask consensus pricing | 35 | [4] | 43 | [4] |
Uranium | Discounted Cash Flow | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Average bid/ask consensus pricing | 43 | [4] | 46 | [4] |
Uranium | Discounted Cash Flow | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Average bid/ask consensus pricing | 36 | [4] | 44 | [4] |
Uranium | Derivative Assets | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative assets | 1 | [1] | ' | [1] |
Uranium | Union Electric Company | Discounted Cash Flow | Minimum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Average bid/ask consensus pricing | 35 | [4] | 43 | [4] |
Uranium | Union Electric Company | Discounted Cash Flow | Maximum | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Average bid/ask consensus pricing | 43 | [4] | 46 | [4] |
Uranium | Union Electric Company | Discounted Cash Flow | Weighted Average | ' | ' | ||
Fair Value Inputs [Abstract] | ' | ' | ||
Average bid/ask consensus pricing | 36 | [4] | 44 | [4] |
Uranium | Union Electric Company | Derivative Assets | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative assets | 1 | [1] | ' | [1] |
Uranium | Derivative Liabilities | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative liabilities | -6 | [1] | -2 | [1] |
Uranium | Derivative Liabilities | Union Electric Company | ' | ' | ||
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] | ' | ' | ||
Derivative liabilities | -6 | [1] | -2 | [1] |
[1] | The derivative asset and liability balances are presented net of counterparty credit considerations. | |||
[2] | Counterparty credit risk is only applied to counterparties with derivative asset balances. Ameren, Ameren Missouri, and Ameren Illinois credit risk is only applied to counterparties with derivative liability balances. | |||
[3] | Generally, significant increases (decreases) in this input in isolation would result in a significantly lower (higher) fair value measurement. | |||
[4] | Generally, significant increases (decreases) in this input in isolation would result in a significantly higher (lower) fair value measurement. | |||
[5] | Escalation rate applies to power prices 2026 and beyond. | |||
[6] | Power valuations utilize visible third-party pricing evaluated by month for peak and off-peak demand through 2017. Valuations beyond 2017 utilize fundamentally modeled pricing by month for peak and off-peak demand. |
Fair_Value_Measurements_Narrat
Fair Value Measurements (Narrative) (Detail) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 |
In Millions, unless otherwise specified | ||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Valuation adjustments related to net derivative contracts, liabilities | $4 | $7 |
Union Electric Company | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Valuation adjustments related to net derivative contracts, liabilities | 1 | 1 |
Ameren Illinois Company | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Valuation adjustments related to net derivative contracts, liabilities | $4 | $7 |
Fair_Value_Measurements_Schedu1
Fair Value Measurements (Schedule Of Fair Value Hierarchy Of Assets And Liabilities Measured At Fair Value On Recurring Basis) (Detail) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 | ||
In Millions, unless otherwise specified | ||||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | $458 | [1] | $406 | [2] |
Assets fair value | 499 | 435 | ||
Excluded receivables, payables, and accrued income, net | 1 | 2 | ||
Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 458 | [1] | 406 | [2] |
Assets fair value | 499 | 434 | ||
Fuel Oils | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 7 | [3] | 8 | [3] |
Natural Gas | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 1 | [3] | ' | |
Commodity Contract | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 41 | [3] | 29 | [3] |
Derivative liabilities | 182 | [3] | 230 | [3] |
Commodity Contract | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 41 | [3] | 28 | [3] |
Derivative liabilities | 26 | [3] | 25 | [3] |
Commodity Contract | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | ' | 1 | ||
Derivative liabilities | 156 | [3] | 205 | [3] |
Commodity Contract | Fuel Oils | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 8 | [3] | 12 | [3] |
Derivative liabilities | 4 | [3] | 4 | [3] |
Commodity Contract | Fuel Oils | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 8 | [3] | 12 | [3] |
Derivative liabilities | 4 | [3] | 4 | [3] |
Commodity Contract | Natural Gas | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 1 | [3] | 2 | [3] |
Derivative liabilities | 75 | [3] | 109 | [3] |
Commodity Contract | Natural Gas | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 1 | [3] | 1 | [3] |
Derivative liabilities | 13 | [3] | 15 | [3] |
Commodity Contract | Natural Gas | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | ' | 1 | [3] | |
Derivative liabilities | 62 | [3] | 94 | [3] |
Commodity Contract | Power | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 31 | [3] | 15 | [3] |
Derivative liabilities | 97 | [3] | 115 | [3] |
Commodity Contract | Power | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 31 | [3] | 15 | [3] |
Derivative liabilities | 3 | [3] | 4 | [3] |
Commodity Contract | Power | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative liabilities | 94 | [3] | 111 | [3] |
Commodity Contract | Uranium | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 1 | [3] | ' | |
Derivative liabilities | 6 | [3] | 2 | [3] |
Commodity Contract | Uranium | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative liabilities | 6 | [3] | 2 | [3] |
Cash and cash equivalents | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 2 | [1] | 1 | [2] |
Cash and cash equivalents | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 2 | [1] | 1 | [2] |
Equity Securities | U.S. large capitalization | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 309 | [1] | 264 | [2] |
Equity Securities | U.S. large capitalization | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 309 | [1] | 264 | [2] |
Debt Securities | Corporate bonds | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 45 | [1] | 47 | [2] |
Debt Securities | Corporate bonds | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 45 | [1] | 47 | [2] |
Debt Securities | Municipal bonds | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 2 | [1] | 1 | [2] |
Debt Securities | Municipal bonds | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 2 | [1] | 1 | [2] |
Debt Securities | US treasury and government securities | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 90 | [1] | 81 | [2] |
Debt Securities | US treasury and government securities | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 90 | [1] | 81 | [2] |
Debt Securities | Asset-backed Securities | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 9 | [1] | 11 | [2] |
Debt Securities | Asset-backed Securities | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 9 | [1] | 11 | [2] |
Debt Securities | Other Debt Securities | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 1 | [1] | 1 | [2] |
Debt Securities | Other Debt Securities | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 1 | [1] | 1 | [2] |
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 311 | [1] | 265 | [2] |
Assets fair value | 312 | 269 | ||
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 311 | [1] | 265 | [2] |
Assets fair value | 312 | 269 | ||
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative liabilities | ' | ' | ||
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Commodity Contract | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 1 | [3] | 4 | [3] |
Derivative liabilities | 5 | [3] | 8 | [3] |
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Commodity Contract | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 1 | [3] | 4 | [3] |
Derivative liabilities | 5 | [3] | 8 | [3] |
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Commodity Contract | Fuel Oils | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 1 | [3] | 4 | [3] |
Derivative liabilities | ' | [3] | 1 | [3] |
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Commodity Contract | Fuel Oils | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 1 | [3] | 4 | [3] |
Derivative liabilities | ' | [3] | 1 | [3] |
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Commodity Contract | Natural Gas | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | ' | [3] | ' | [3] |
Derivative liabilities | 5 | [3] | 7 | [3] |
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Commodity Contract | Natural Gas | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | ' | [3] | ' | [3] |
Derivative liabilities | 5 | [3] | 7 | [3] |
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Commodity Contract | Natural Gas | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative liabilities | ' | ' | [3] | |
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Cash and cash equivalents | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 2 | [1] | 1 | [2] |
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Cash and cash equivalents | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 2 | [1] | 1 | [2] |
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Equity Securities | U.S. large capitalization | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 309 | [1] | 264 | [2] |
Quoted Prices In Active Markets For Identical Assets or Liabilities (Level 1) | Equity Securities | U.S. large capitalization | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 309 | [1] | 264 | [2] |
Significant Other Observable Inputs (Level 2) | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 147 | [1] | 141 | [2] |
Assets fair value | 149 | 144 | ||
Significant Other Observable Inputs (Level 2) | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 147 | [1] | 141 | [2] |
Assets fair value | 149 | 143 | ||
Significant Other Observable Inputs (Level 2) | Commodity Contract | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 2 | [3] | 3 | [3] |
Derivative liabilities | 71 | [3] | 103 | [3] |
Significant Other Observable Inputs (Level 2) | Commodity Contract | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 2 | [3] | 2 | [3] |
Derivative liabilities | 9 | [3] | 9 | [3] |
Significant Other Observable Inputs (Level 2) | Commodity Contract | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative liabilities | 62 | [3] | 94 | [3] |
Significant Other Observable Inputs (Level 2) | Commodity Contract | Natural Gas | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | ' | [3] | 2 | [3] |
Derivative liabilities | 69 | [3] | 102 | [3] |
Significant Other Observable Inputs (Level 2) | Commodity Contract | Natural Gas | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | ' | [3] | 1 | [3] |
Derivative liabilities | 7 | [3] | 8 | [3] |
Significant Other Observable Inputs (Level 2) | Commodity Contract | Natural Gas | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | ' | 1 | [3] | |
Derivative liabilities | 62 | [3] | 94 | [3] |
Significant Other Observable Inputs (Level 2) | Commodity Contract | Power | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 2 | [3] | 1 | [3] |
Derivative liabilities | 2 | [3] | 1 | [3] |
Significant Other Observable Inputs (Level 2) | Commodity Contract | Power | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 2 | [3] | 1 | [3] |
Derivative liabilities | 2 | [3] | 1 | [3] |
Significant Other Observable Inputs (Level 2) | Commodity Contract | Power | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative liabilities | ' | ' | [3] | |
Significant Other Observable Inputs (Level 2) | Debt Securities | Corporate bonds | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 45 | [1] | 47 | [2] |
Significant Other Observable Inputs (Level 2) | Debt Securities | Corporate bonds | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 45 | [1] | 47 | [2] |
Significant Other Observable Inputs (Level 2) | Debt Securities | Municipal bonds | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 2 | [1] | 1 | [2] |
Significant Other Observable Inputs (Level 2) | Debt Securities | Municipal bonds | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 2 | [1] | 1 | [2] |
Significant Other Observable Inputs (Level 2) | Debt Securities | US treasury and government securities | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 90 | [1] | 81 | [2] |
Significant Other Observable Inputs (Level 2) | Debt Securities | US treasury and government securities | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 90 | [1] | 81 | [2] |
Significant Other Observable Inputs (Level 2) | Debt Securities | Asset-backed Securities | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 9 | [1] | 11 | [2] |
Significant Other Observable Inputs (Level 2) | Debt Securities | Asset-backed Securities | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 9 | [1] | 11 | [2] |
Significant Other Observable Inputs (Level 2) | Debt Securities | Other Debt Securities | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 1 | [1] | 1 | [2] |
Significant Other Observable Inputs (Level 2) | Debt Securities | Other Debt Securities | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Nuclear Decommissioning Trust Fund | 1 | [1] | 1 | [2] |
Significant Other Unobservable Inputs (Level 3) | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Assets fair value | 38 | [3] | 22 | [3] |
Significant Other Unobservable Inputs (Level 3) | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Assets fair value | 38 | [3] | 22 | [3] |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 38 | [3] | 22 | [3] |
Derivative liabilities | 106 | [3] | 119 | [3] |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 38 | [3] | 22 | [3] |
Derivative liabilities | 12 | [3] | 8 | [3] |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative liabilities | 94 | [3] | 111 | [3] |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | Fuel Oils | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 7 | [3] | 8 | [3] |
Derivative liabilities | 4 | [3] | 3 | [3] |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | Fuel Oils | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 7 | [3] | 8 | [3] |
Derivative liabilities | 4 | [3] | 3 | [3] |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | Natural Gas | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 1 | [3] | ' | [3] |
Derivative liabilities | 1 | [3] | ' | [3] |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | Natural Gas | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 1 | [3] | ' | |
Derivative liabilities | 1 | [3] | ' | [3] |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | Natural Gas | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | ' | ' | [3] | |
Derivative liabilities | ' | ' | [3] | |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | Power | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 29 | [3] | 14 | [3] |
Derivative liabilities | 95 | [3] | 114 | [3] |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | Power | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 29 | [3] | 14 | [3] |
Derivative liabilities | 1 | [3] | 3 | [3] |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | Power | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative liabilities | 94 | [3] | 111 | [3] |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | Uranium | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 1 | [3] | ' | |
Derivative liabilities | 6 | [3] | 2 | [3] |
Significant Other Unobservable Inputs (Level 3) | Commodity Contract | Uranium | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Derivative assets | 1 | [3] | ' | |
Derivative liabilities | $6 | [3] | $2 | [3] |
[1] | Balance excludes $1 million of receivables, payables, and accrued income, net. | |||
[2] | Balance excludes $2 million of receivables, payables, and accrued income, net. | |||
[3] | The derivative asset and liability balances are presented net of counterparty credit considerations. |
Fair_Value_Measurements_Schedu2
Fair Value Measurements (Schedule Of Changes In The Fair Value Of Financial Assets And Liabilities Classified As Level Three In The Fair Value Hierarchy) (Detail) (USD $) | 3 Months Ended | 9 Months Ended | ||||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | ||
Fuel Oils | ' | ' | ' | ' | ||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ' | ' | ' | ' | ||
Beginning balance | $3 | $3 | $5 | $3 | ||
Included in regulatory assets/liabilities | 1 | 1 | -1 | -1 | ||
Total realized and unrealized gains (losses) | 1 | 1 | -1 | -1 | ||
Purchases | 1 | 2 | 2 | 4 | ||
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales | -1 | -1 | -1 | -2 | ||
Settlements | -1 | ' | -2 | -1 | ||
Transfers into Level 3 | ' | ' | ' | 2 | ||
Ending balance | 3 | 5 | 3 | 5 | ||
Change in unrealized gains (losses) related to assets/liabilities held at period end | 1 | 2 | 0 | -1 | ||
Uranium | ' | ' | ' | ' | ||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ' | ' | ' | ' | ||
Beginning balance | -3 | -1 | -2 | -1 | ||
Included in regulatory assets/liabilities | ' | -1 | -2 | -1 | ||
Total realized and unrealized gains (losses) | ' | -1 | -2 | -1 | ||
Purchases | ' | ' | -2 | ' | ||
Settlements | -2 | ' | 1 | ' | ||
Ending balance | -5 | -2 | -5 | -2 | ||
Change in unrealized gains (losses) related to assets/liabilities held at period end | -2 | -1 | -2 | -1 | ||
Natural Gas | ' | ' | ' | ' | ||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ' | ' | ' | ' | ||
Beginning balance | 1 | ' | 0 | -174 | ||
Included in regulatory assets/liabilities | -2 | ' | -1 | -28 | ||
Total realized and unrealized gains (losses) | -2 | ' | -1 | -28 | ||
Purchases | 1 | ' | 1 | ' | ||
Settlements | ' | ' | ' | 17 | ||
Transfer out of Level 3 | ' | ' | ' | 185 | ||
Ending balance | 0 | 0 | 0 | 0 | ||
Change in unrealized gains (losses) related to assets/liabilities held at period end | -1 | ' | ' | 7 | ||
Power | ' | ' | ' | ' | ||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ' | ' | ' | ' | ||
Beginning balance | -43 | -81 | [1] | -100 | 81 | |
Included in regulatory assets/liabilities | -20 | -6 | [1] | 1 | -174 | [1] |
Total realized and unrealized gains (losses) | -20 | -6 | [1] | 1 | -174 | [1] |
Purchases | ' | ' | 40 | 22 | ||
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales | 1 | -1 | [1] | 1 | -1 | |
Settlements | -3 | -1 | [1] | -9 | -15 | [1] |
Transfers into Level 3 | 1 | ' | -3 | ' | ||
Transfer out of Level 3 | ' | -2 | [1] | 4 | 4 | |
Ending balance | -66 | -91 | [1] | -66 | -91 | [1] |
Change in unrealized gains (losses) related to assets/liabilities held at period end | -18 | -7 | [1] | -7 | -171 | |
Union Electric Company | Fuel Oils | ' | ' | ' | ' | ||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ' | ' | ' | ' | ||
Beginning balance | 3 | 3 | 5 | 3 | ||
Included in regulatory assets/liabilities | 1 | 1 | -1 | -1 | ||
Total realized and unrealized gains (losses) | 1 | 1 | -1 | -1 | ||
Purchases | 1 | 2 | 2 | 4 | ||
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales | -1 | -1 | -1 | -2 | ||
Settlements | -1 | ' | -2 | -1 | ||
Transfers into Level 3 | ' | ' | ' | 2 | ||
Ending balance | 3 | 5 | 3 | 5 | ||
Change in unrealized gains (losses) related to assets/liabilities held at period end | 1 | 2 | 0 | -1 | ||
Union Electric Company | Uranium | ' | ' | ' | ' | ||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ' | ' | ' | ' | ||
Beginning balance | -3 | -1 | -2 | -1 | ||
Included in regulatory assets/liabilities | ' | -1 | -2 | -1 | ||
Total realized and unrealized gains (losses) | ' | -1 | -2 | -1 | ||
Purchases | ' | ' | -2 | ' | ||
Settlements | -2 | ' | 1 | ' | ||
Ending balance | -5 | -2 | -5 | -2 | ||
Change in unrealized gains (losses) related to assets/liabilities held at period end | -2 | -1 | -2 | -1 | ||
Union Electric Company | Natural Gas | ' | ' | ' | ' | ||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ' | ' | ' | ' | ||
Beginning balance | -1 | ' | 0 | -14 | ||
Included in regulatory assets/liabilities | ' | ' | ' | -2 | ||
Total realized and unrealized gains (losses) | ' | ' | ' | -2 | ||
Purchases | 1 | ' | ' | ' | ||
Settlements | ' | ' | ' | -1 | ||
Transfer out of Level 3 | ' | ' | ' | 15 | ||
Ending balance | 0 | 0 | 0 | 0 | ||
Change in unrealized gains (losses) related to assets/liabilities held at period end | ' | ' | ' | 7 | ||
Union Electric Company | Power | ' | ' | ' | ' | ||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ' | ' | ' | ' | ||
Beginning balance | 37 | 26 | 11 | 21 | ||
Included in regulatory assets/liabilities | -3 | -4 | 3 | 5 | ||
Total realized and unrealized gains (losses) | -3 | -4 | 3 | 5 | ||
Purchases | ' | ' | 40 | 22 | ||
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales | 1 | -1 | 1 | -1 | ||
Settlements | -6 | -4 | -28 | 28 | ||
Transfers into Level 3 | 1 | ' | -3 | ' | ||
Transfer out of Level 3 | ' | -2 | 4 | -4 | ||
Ending balance | 28 | 15 | 28 | 15 | ||
Change in unrealized gains (losses) related to assets/liabilities held at period end | -2 | -5 | ' | -1 | ||
Ameren Illinois Company | Natural Gas | ' | ' | ' | ' | ||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ' | ' | ' | ' | ||
Beginning balance | 2 | ' | 0 | -160 | ||
Included in regulatory assets/liabilities | -2 | ' | -1 | -26 | ||
Total realized and unrealized gains (losses) | -2 | ' | -1 | -26 | ||
Purchases | ' | ' | 1 | ' | ||
Settlements | ' | ' | ' | -16 | ||
Transfer out of Level 3 | ' | ' | ' | 170 | ||
Ending balance | 0 | 0 | 0 | 0 | ||
Change in unrealized gains (losses) related to assets/liabilities held at period end | -1 | ' | ' | 0 | ||
Ameren Illinois Company | Power | ' | ' | ' | ' | ||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ' | ' | ' | ' | ||
Beginning balance | -80 | -221 | -111 | -140 | ||
Included in regulatory assets/liabilities | -17 | 2 | -2 | -219 | ||
Total realized and unrealized gains (losses) | -17 | 2 | -2 | -219 | ||
Purchases | ' | ' | ' | 0 | ||
Settlements | 3 | 54 | 19 | -194 | ||
Transfers into Level 3 | ' | ' | ' | ' | ||
Transfer out of Level 3 | ' | ' | 0 | ' | ||
Ending balance | -94 | -165 | -94 | -165 | ||
Change in unrealized gains (losses) related to assets/liabilities held at period end | ($16) | ($2) | ($7) | ($187) | [2] | |
[1] | Ameren amounts include the elimination of financial power contracts between Ameren Illinois and Marketing Company. | |||||
[2] | The change in unrealized losses was due to decreases in long-term power prices applied to 20-year Ameren Illinois’ swap contracts, which expire May 2032. |
Fair_Value_Measurements_Schedu3
Fair Value Measurements (Schedule Of Transfers Between Fair Value Hierarchy Levels) (Detail) (USD $) | 3 Months Ended | 9 Months Ended | |||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | |
Derivative [Line Items] | ' | ' | ' | ' | |
Net fair value of Level 3 transfers | ($1) | ($2) | $1 | $183 | |
Fuel Oils | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers into Level 3 | ' | ' | ' | -2 | |
Fuel Oils | Transfer Into/Out of Level 1 | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers into Level 3 | ' | ' | ' | 2 | |
Natural Gas | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers out of Level 3 | ' | ' | ' | 185 | |
Natural Gas | Transfer Into/Out of Level 2 | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers out of Level 3 | ' | ' | ' | 185 | |
Power | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers into Level 3 | -1 | ' | 3 | ' | |
Assets Transfers out of Level 3 | ' | -2 | [1] | 4 | 4 |
Power | Transfer Into/Out of Level 2 | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers into Level 3 | -1 | ' | -3 | ' | |
Assets Transfers out of Level 3 | ' | -2 | 4 | -4 | |
Union Electric Company | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Net fair value of Level 3 transfers | -1 | -2 | 1 | 13 | |
Union Electric Company | Fuel Oils | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers into Level 3 | ' | ' | ' | -2 | |
Union Electric Company | Fuel Oils | Transfer Into/Out of Level 1 | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers into Level 3 | ' | ' | ' | 2 | |
Union Electric Company | Natural Gas | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers out of Level 3 | ' | ' | ' | 15 | |
Union Electric Company | Natural Gas | Transfer Into/Out of Level 2 | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers out of Level 3 | ' | ' | ' | 15 | |
Union Electric Company | Power | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers into Level 3 | -1 | ' | 3 | ' | |
Assets Transfers out of Level 3 | ' | -2 | 4 | -4 | |
Union Electric Company | Power | Transfer Into/Out of Level 2 | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers into Level 3 | -1 | ' | -3 | ' | |
Assets Transfers out of Level 3 | ' | -2 | 4 | -4 | |
Ameren Illinois Company | Natural Gas | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers out of Level 3 | ' | ' | ' | 170 | |
Ameren Illinois Company | Natural Gas | Transfer Into/Out of Level 2 | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers out of Level 3 | ' | ' | ' | 170 | |
Ameren Illinois Company | Power | ' | ' | ' | ' | |
Derivative [Line Items] | ' | ' | ' | ' | |
Assets Transfers into Level 3 | ' | ' | ' | ' | |
Assets Transfers out of Level 3 | ' | ' | $0 | ' | |
[1] | Ameren amounts include the elimination of financial power contracts between Ameren Illinois and Marketing Company. |
Fair_Value_Measurements_Schedu4
Fair Value Measurements (Schedule Of Carrying Amounts And Estimated Fair Values Of Long-Term Debt And Preferred Stock) (Detail) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 | ||
In Millions, unless otherwise specified | ||||
Fair Value | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Long-term debt (including current portion) | $6,596 | [1],[2] | $7,110 | [1],[2] |
Preferred stock | 123 | [1],[2] | 123 | [1],[2] |
Fair Value | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Long-term debt (including current portion) | 4,227 | 4,625 | ||
Preferred stock | 74 | 74 | ||
Fair Value | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Long-term debt (including current portion) | 1,922 | 2,020 | ||
Preferred stock | 49 | 49 | ||
Carrying Amount | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Long-term debt (including current portion) | 6,158 | [1],[2] | 6,157 | [1],[2] |
Preferred stock | 142 | [1],[2] | 142 | [1],[2] |
Carrying Amount | Union Electric Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Long-term debt (including current portion) | 4,006 | 4,006 | ||
Preferred stock | 80 | 80 | ||
Carrying Amount | Ameren Illinois Company | ' | ' | ||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ||
Long-term debt (including current portion) | 1,727 | 1,727 | ||
Preferred stock | $62 | $62 | ||
[1] | Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations. | |||
[2] | Preferred stock along with the noncontrolling interest of EEI is recorded in “Noncontrolling Interests†on the balance sheet. |
Related_Party_Transactions_Nar
Related Party Transactions (Narrative) (Detail) (USD $) | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Mar. 14, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2012 |
In Millions, unless otherwise specified | Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company | Union Electric Company | Union Electric Company | Union Electric Company | Union Electric Company | Futures Commission Merchants | Ameren Energy Marketing Company | Ameren Energy Marketing Company | Related Party One | Related Party One | Related Party One | Related Party One | Related Party One | Related Party One | Related Party One | Related Party One | Guarantee Type, Other | New Ameren Energy Resources Company, LLC | Miscellaneous Support Services | Miscellaneous Support Services | Miscellaneous Support Services | Miscellaneous Support Services | |
Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company | Ameren Illinois Company | Union Electric Company | Union Electric Company | Union Electric Company | Union Electric Company | Related Party One | Related Party One | Related Party One | Related Party One | ||||||||||||||
Ameren Illinois Company | Union Electric Company | Union Electric Company | Union Electric Company | |||||||||||||||||||||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Accounts payable, related parties | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | $17 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Purchase of receivables from Marketing Company | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 115 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Related Party Transaction, Purchases of Financing Receivable, Discount | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 2 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Related Party Transaction, Guarantees Outstanding | 192 | ' | ' | ' | ' | ' | ' | ' | ' | 25 | 154 | ' | ' | ' | ' | ' | ' | ' | ' | ' | 13 | ' | ' | ' | ' | ' |
Related Party Transaction, Guarantees, Maximum Exposure | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 25 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Letters of Credit Outstanding, Amount | 14 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Obligation to provide credit support, period | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | '24 months | ' | ' | ' | ' |
Buyer's indemnification guarantee obligation | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 25 | ' | ' | ' | ' |
Buyer's indemnification guarantee obligation, period | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | '24 months | ' | ' | ' | ' |
Revenue from Related Parties | ' | ' | ' | $2 | ' | $1 | ' | $1 | $1 | ' | ' | ' | $11 | $5 | $25 | $12 | $4 | $5 | $17 | $15 | ' | ' | $2 | $1 | $1 | $1 |
Related_Party_Transactions_Sch
Related Party Transactions (Schedule of Related Party Transactions) (Detail) (USD $) | 3 Months Ended | 9 Months Ended | ||||||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | ||||
Union Electric Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Revenues | $1 | ' | $1 | $1 | ||||
Operating Expenses | 25 | 26 | 85 | 81 | ||||
Ameren Illinois Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Revenues | ' | ' | 2 | ' | ||||
Operating Expenses | 22 | 22 | 70 | 67 | ||||
Related Party One | Union Electric Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Revenues | 4 | 5 | 17 | 15 | ||||
Related Party One | Ameren Illinois Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Revenues | 11 | 5 | 25 | 12 | ||||
Ameren Missouri Power Supply Agreements with Ameren Illinois | Union Electric Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Revenues | 1 | [1] | 1 | [1] | 1 | 1 | [1] | |
Ameren Missouri and Ameren Illinois Rent and Facility Services | Union Electric Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Revenues | 4 | 5 | 15 | 14 | ||||
Ameren Missouri and Ameren Illinois Rent and Facility Services | Ameren Illinois Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Revenues | 1 | [1] | 1 | [1] | 1 | 1 | ||
Ameren Missouri and Genco Gas Transportation Agreement | Union Electric Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Revenues | 1 | [1] | 1 | [1] | 1 | 1 | ||
Ameren Illinois Transmission Services Agreement with Marketing Company | Ameren Illinois Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Revenues | 11 | 5 | 24 | 11 | ||||
Ameren Illinois Power Supply Agreements with Marketing Company | Ameren Illinois Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Expenses | 46 | 83 | 94 | 243 | ||||
Purchased Power | Ameren Illinois Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Expenses | 46 | 83 | 95 | 243 | ||||
Ameren Services Support Services Agreement | Union Electric Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Expenses | 25 | 26 | 85 | 81 | ||||
Ameren Services Support Services Agreement | Ameren Illinois Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Expenses | 22 | 22 | 70 | 67 | ||||
Ameren Illinois Power Supply Agreements with Ameren Missouri | Ameren Illinois Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Expenses | 1 | [1] | 1 | [1] | 1 | 1 | [1] | |
Related Party Money Pool Interest | Union Electric Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Interest Charges | 1 | [1] | 1 | [1] | 1 | 1 | [1] | |
Related Party Money Pool Interest | Ameren Illinois Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Interest Charges | 1 | [1] | 1 | [1] | 1 | [1] | 1 | [1] |
Insurance Premiums | Union Electric Company | ' | ' | ' | ' | ||||
Related Party Transaction [Line Items] | ' | ' | ' | ' | ||||
Operating Expenses | $1 | [1],[2] | $1 | [1],[2] | $1 | [1],[2] | $1 | [1],[2] |
[1] | Amount less than $1 million. | |||||||
[2] | Represents insurance premiums paid to Missouri Energy Risk Assurance Company, an affiliate, for replacement power. |
Commitments_And_Contingencies_1
Commitments And Contingencies (Callaway Energy Center) (Detail) (USD $) | 9 Months Ended | |
Sep. 30, 2013 | ||
Commitments And Contingencies [Line Items] | ' | |
Threshold for which a retrospective assessment for a covered loss is necessary | $375,000,000 | |
Annual payment in the event of an incident at any licensed commercial reactor | 19,000,000 | |
Aggregate maximum assessment per incident under Price-Anderson liability provisions of Atomic Energy Act | 128,000,000 | |
Maximum annual payment in calendar year per reactor incident under Price Andersen Liability Provisions of Atomic Energy Act | 19,000,000 | |
Amount of coverage in excess of primary property liability coverage | 2,250,000,000 | |
Sub-limit for non-nuclear events | 1,700,000,000 | |
Amount of weekly indemnity coverage commencing eight weeks after power outage | 4,500,000 | |
Number of weeks of coverage after the first eight weeks of an outage | '1 year | |
Amount of additional weekly indemnity coverage commencing after initial indemnity coverage | 3,600,000 | |
Number of additional weeks after initial indemnity coverage for power outage, minimum | '1 year 4 months 10 days | |
Amount of secondary weekly indemnity coverage for prolonged nuclear plant outage in excess of primary indemnity coverage | 900,000 | |
Inflationary adjustment prescribed by most recent Price-Anderson Act renewal, in years | '5 years | |
Aggregate nuclear power industry insurance policy limit for losses from terrorist attacks within twelve month period | 3,240,000,000 | |
Public Liability | ' | |
Commitments And Contingencies [Line Items] | ' | |
Maximum Coverages | 13,687,000,000 | [1] |
Maximum Assessments for Single Incidents | 128,000,000 | |
Public Liability And Nuclear Worker Liability - American Nuclear Insurers [Member] | ' | |
Commitments And Contingencies [Line Items] | ' | |
Maximum Coverages | 375,000,000 | |
Public Liability And Nuclear Worker Liability - Pool Participation [Member] | ' | |
Commitments And Contingencies [Line Items] | ' | |
Maximum Coverages | 13,312,000,000 | [2] |
Maximum Assessments for Single Incidents | 128,000,000 | [3] |
Property Damage | ' | |
Commitments And Contingencies [Line Items] | ' | |
Maximum Coverages | 2,750,000,000 | |
Maximum Assessments for Single Incidents | 23,000,000 | |
Property Damage - Nuclear Electric Insurance Ltd [Member] | ' | |
Commitments And Contingencies [Line Items] | ' | |
Maximum Coverages | 2,250,000,000 | [4] |
Maximum Assessments for Single Incidents | 23,000,000 | [5] |
Sub-limit for non-nuclear events | 200,000,000 | |
Property Damage European Mutual Association for Nuclear Insurance [Member] | ' | |
Commitments And Contingencies [Line Items] | ' | |
Maximum Coverages | 500,000,000 | [6] |
Amount of primary property liability coverage | 500,000,000 | |
Replacement Power - Nuclear Electric Insurance Ltd [Member] | ' | |
Commitments And Contingencies [Line Items] | ' | |
Maximum Coverages | 490,000,000 | [7] |
Maximum Assessments for Single Incidents | 9,000,000 | [5] |
Amount of weekly indemnity coverage thereafter not exceeding policy limit | 490,000,000 | |
Sub-limit of for non-nuclear events | 327,600,000 | |
Replacement Power - Energy Risk Assurance Company [Member] | ' | |
Commitments And Contingencies [Line Items] | ' | |
Maximum Coverages | 64,000,000 | [8] |
Amount of weekly indemnity coverage thereafter not exceeding policy limit | $3,600,000 | |
[1] | Limit of liability for each incident under the Price-Anderson liability provisions of the Atomic Energy Act of 1954, as amended. A company could be assessed up to $128 million per incident for each licensed reactor it operates with a maximum of $19 million per incident to be paid in a calendar year for each reactor. This limit is subject to change to account for the effects of inflation and changes in the number of licensed reactors. | |
[2] | Provided through mandatory participation in an industry-wide retrospective premium assessment program. | |
[3] | Retrospective premium under Price-Anderson. This is subject to retrospective assessment with respect to a covered loss in excess of $375 million in the event of an incident at any licensed United States commercial reactor, payable at $19 million per year. | |
[4] | Nuclear Electric Insurance Ltd. provides $2.25 billion in property damage, decontamination, and premature decommissioning insurance. There is a $1.7 billion sublimit for non-radiation events of which the top $200 million is a shared limit with other generators purchasing this coverage and includes one free reinstatement. | |
[5] | All Nuclear Electric Insurance Ltd. insured plants could be subject to assessments should losses exceed the accumulated funds from Nuclear Electric Insurance Ltd. | |
[6] | European Mutual Association for Nuclear Insurance provides $500 million in excess of the $2.25 billion property coverage and $1.7 billion non-radiation coverage. | |
[7] | Provides replacement power cost insurance in the event of a prolonged accidental outage at our nuclear energy center. Weekly indemnity up to $4.5 million for 52 weeks, which commences after the first eight weeks of an outage, plus up to $3.6 million per week for a minimum of 71 weeks thereafter for a total not exceeding the policy limit of $490 million. Effective April 1, 2013, non-radiation events are sub-limited to $327.6 million. | |
[8] | Provides replacement power cost insurance in the event of a prolonged accidental outage at our nuclear energy center. The coverage commences after the first 52 weeks of insurance coverage from Nuclear Electric Insurance Ltd. and is for a weekly indemnity up to $900,000 for 71 weeks in excess of the $3.6 million per week set forth above. Missouri Energy Risk Assurance Company LLC is an affiliate and has reinsured this coverage with third-party insurance companies. See Note 9 - Related Party Transactions for more information on this affiliate transaction. |
Commitments_And_Contingencies_2
Commitments And Contingencies (Schedule of Estimated Purchase Commitments) (Detail) (USD $) | 9 Months Ended | |
In Millions, unless otherwise specified | Sep. 30, 2013 | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | $981 | [1] |
2014 | 1,440 | [1] |
2015 | 1,130 | [1] |
2016 | 966 | [1] |
2017 | 893 | [1] |
Thereafter | 1,405 | [1] |
Total | 6,815 | [1] |
Union Electric Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 719 | |
2014 | 884 | |
2015 | 841 | |
2016 | 825 | |
2017 | 808 | |
Thereafter | 859 | |
Total | 4,936 | |
Ameren Illinois Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 250 | |
2014 | 547 | |
2015 | 284 | |
2016 | 141 | |
2017 | 85 | |
Thereafter | 546 | |
Total | 1,853 | |
Investment in Energy Efficiency Programs | Union Electric Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
Other Commitment | 147 | |
Other Commitments, Term | '3 years | |
Coal | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 605 | [1] |
2014 | 617 | [1] |
2015 | 640 | [1] |
2016 | 665 | [1] |
2017 | 683 | [1] |
Thereafter | 245 | [1] |
Total | 3,455 | [1] |
Coal | Union Electric Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 605 | |
2014 | 617 | |
2015 | 640 | |
2016 | 665 | |
2017 | 683 | |
Thereafter | 245 | |
Total | 3,455 | |
Coal | Ameren Illinois Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | ' | |
2014 | ' | |
2015 | ' | |
2016 | ' | |
2017 | ' | |
Thereafter | ' | |
Total | ' | |
Natural Gas | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 109 | [1] |
2014 | 292 | [1] |
2015 | 155 | [1] |
2016 | 85 | [1] |
2017 | 47 | [1] |
Thereafter | 100 | [1] |
Total | 788 | [1] |
Natural Gas | Union Electric Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 27 | |
2014 | 50 | |
2015 | 30 | |
2016 | 16 | |
2017 | 11 | |
Thereafter | 28 | |
Total | 162 | |
Natural Gas | Ameren Illinois Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 82 | |
2014 | 242 | |
2015 | 125 | |
2016 | 69 | |
2017 | 36 | |
Thereafter | 72 | |
Total | 626 | |
Nuclear Fuel | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 17 | [1] |
2014 | 68 | [1] |
2015 | 63 | [1] |
2016 | 81 | [1] |
2017 | 58 | [1] |
Thereafter | 216 | [1] |
Total | 503 | [1] |
Nuclear Fuel | Union Electric Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 17 | |
2014 | 68 | |
2015 | 63 | |
2016 | 81 | |
2017 | 58 | |
Thereafter | 216 | |
Total | 503 | |
Nuclear Fuel | Ameren Illinois Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | ' | |
2014 | ' | |
2015 | ' | |
2016 | ' | |
2017 | ' | |
Thereafter | ' | |
Total | ' | |
Purchased Power | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 162 | [1],[2] |
2014 | 302 | [1],[2] |
2015 | 154 | [1],[2] |
2016 | 67 | [1],[2] |
2017 | 44 | [1],[2] |
Thereafter | 501 | [1],[2] |
Total | 1,230 | [1],[2] |
Purchased Power | Union Electric Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 3 | [2] |
2014 | 19 | [2] |
2015 | 19 | [2] |
2016 | 19 | [2] |
2017 | 19 | [2] |
Thereafter | 129 | [2] |
Total | 208 | [2] |
Purchased Power | Ameren Illinois Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 159 | [2] |
2014 | 283 | [2] |
2015 | 135 | [2] |
2016 | 48 | [2] |
2017 | 25 | [2] |
Thereafter | 372 | [2] |
Total | 1,022 | [2] |
Renewable Energy Credits Agreements, Term | '20 years | |
Methane Gas | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 1 | [1] |
2014 | 3 | [1] |
2015 | 4 | [1] |
2016 | 4 | [1] |
2017 | 5 | [1] |
Thereafter | 97 | [1] |
Total | 114 | [1] |
Methane Gas | Union Electric Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 1 | |
2014 | 3 | |
2015 | 4 | |
2016 | 4 | |
2017 | 5 | |
Thereafter | 97 | |
Total | 114 | |
Methane Gas | Ameren Illinois Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | ' | |
2014 | ' | |
2015 | ' | |
2016 | ' | |
2017 | ' | |
Thereafter | ' | |
Total | ' | |
Other Purchased Fuel | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 87 | [1] |
2014 | 158 | [1] |
2015 | 114 | [1] |
2016 | 64 | [1] |
2017 | 56 | [1] |
Thereafter | 246 | [1] |
Total | 725 | [1] |
Other Purchased Fuel | Union Electric Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 66 | |
2014 | 127 | |
2015 | 85 | |
2016 | 40 | |
2017 | 32 | |
Thereafter | 144 | |
Total | 494 | |
Other Purchased Fuel | Ameren Illinois Company | ' | |
Long-term Purchase Commitment [Line Items] | ' | |
2013 | 9 | |
2014 | 22 | |
2015 | 24 | |
2016 | 24 | |
2017 | 24 | |
Thereafter | 102 | |
Total | $205 | |
[1] | Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations. | |
[2] | The purchased power amounts for Ameren and Ameren Illinois includes twenty-year agreements for renewable energy credits that were entered into in December 2010 with various renewable energy suppliers. The agreements contain a provision that allows Ameren Illinois to reduce the quantity purchased in the event that Ameren Illinois would not be able to recover the costs associated with the renewable energy credits. |
Commitments_And_Contingencies_3
Commitments And Contingencies (Environmental Matters) (Detail) (USD $) | 9 Months Ended | |
In Millions, unless otherwise specified | Sep. 30, 2013 | |
State | ||
Minimum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 395 | [1] |
Maximum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 480 | [1] |
Estimated Capital Costs 2013 | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 35 | [1] |
Estimated Capital Costs 2014 to 2017 | Minimum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 120 | [1] |
Estimated Capital Costs 2014 to 2017 | Maximum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 150 | [1] |
Estimated Capital Costs 2018 to 2022 | Minimum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 240 | [1] |
Estimated Capital Costs 2018 to 2022 | Maximum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 295 | [1] |
Ameren Energy Generating Company | Minimum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 350 | [2] |
Ameren Energy Generating Company | Maximum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 425 | [2] |
Ameren Energy Generating Company | Estimated Capital Costs 2013 | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 30 | [2] |
Ameren Energy Generating Company | Estimated Capital Costs 2014 to 2017 | Minimum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 100 | [2] |
Ameren Energy Generating Company | Estimated Capital Costs 2014 to 2017 | Maximum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 125 | [2] |
Ameren Energy Generating Company | Estimated Capital Costs 2018 to 2022 | Minimum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 220 | [2] |
Ameren Energy Generating Company | Estimated Capital Costs 2018 to 2022 | Maximum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 270 | [2] |
Union Electric Company | Minimum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 1,115 | [3] |
Union Electric Company | Maximum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 1,340 | [3] |
Union Electric Company | Estimated Capital Costs 2013 | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 105 | [3] |
Union Electric Company | Estimated Capital Costs 2014 to 2017 | Minimum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 215 | [3] |
Union Electric Company | Estimated Capital Costs 2014 to 2017 | Maximum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 260 | [3] |
Union Electric Company | Estimated Capital Costs 2018 to 2022 | Minimum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 795 | [3] |
Union Electric Company | Estimated Capital Costs 2018 to 2022 | Maximum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 975 | [3] |
AERG | Minimum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 45 | |
AERG | Maximum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 55 | |
AERG | Estimated Capital Costs 2013 | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 5 | |
AERG | Estimated Capital Costs 2014 to 2017 | Minimum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 20 | |
AERG | Estimated Capital Costs 2014 to 2017 | Maximum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 25 | |
AERG | Estimated Capital Costs 2018 to 2022 | Minimum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 20 | |
AERG | Estimated Capital Costs 2018 to 2022 | Maximum | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state environmental regulations | 25 | |
CAIR | ' | |
Loss Contingencies [Line Items] | ' | |
Number of states participating in the cap-and-trade program | 28 | |
MATS | ' | |
Loss Contingencies [Line Items] | ' | |
Percent of top performing facilities | 12.00% | |
Former Coal Tar Distillery | Union Electric Company | ' | |
Loss Contingencies [Line Items] | ' | |
Range of possible loss, minimum | 2 | |
Range of possible loss maximum | 5 | |
Accrual for environmental loss contingencies | 2 | |
Former Coal Ash Landfill | Ameren Illinois Company | ' | |
Loss Contingencies [Line Items] | ' | |
Range of possible loss, minimum | 0.5 | |
Range of possible loss maximum | 6 | |
Accrual for environmental loss contingencies | 0.5 | |
Newton Energy Center Scrubbers | Ameren Energy Generating Company | Newton Energy Center Estimated Capital Costs 2013 to 2017 | ' | |
Loss Contingencies [Line Items] | ' | |
Estimated capital costs to comply with existing and known federal and state air emissions regulations | 20 | |
Manufactured Gas Plant | ' | |
Loss Contingencies [Line Items] | ' | |
Range of possible loss, minimum | 251 | |
Range of possible loss maximum | 337 | |
Accrual for environmental loss contingencies | 251 | [4] |
Manufactured Gas Plant | Union Electric Company | ' | |
Loss Contingencies [Line Items] | ' | |
Range of possible loss, minimum | 5 | |
Range of possible loss maximum | 6 | |
Accrual for environmental loss contingencies | 5 | [4] |
Manufactured Gas Plant | Ameren Illinois Company | ' | |
Loss Contingencies [Line Items] | ' | |
Number of remediation sites | 44 | |
Range of possible loss, minimum | 246 | |
Range of possible loss maximum | 331 | |
Accrual for environmental loss contingencies | 246 | [4] |
Other Environmental | Ameren Illinois Company | ' | |
Loss Contingencies [Line Items] | ' | |
Accrual for environmental loss contingencies | 0.8 | |
Sauget Area Two | Union Electric Company | ' | |
Loss Contingencies [Line Items] | ' | |
Range of possible loss, minimum | 0.3 | |
Range of possible loss maximum | 10 | |
Accrual for environmental loss contingencies | 0.3 | |
Substation in St Charles, Missouri | Union Electric Company | ' | |
Loss Contingencies [Line Items] | ' | |
Range of possible loss, minimum | 1.6 | |
Range of possible loss maximum | 4.5 | |
Accrual for environmental loss contingencies | 1.6 | |
[1] | Assumes the Merchant Generation facilities are owned by Ameren. | |
[2] | Includes estimated costs of approximately $20 million annually, excluding capitalized interest, from 2013 through 2017 for construction of two scrubbers at the Newton energy center. | |
[3] | Ameren Missouri’s expenditures are expected to be recoverable from ratepayers. | |
[4] | Recorded liability represents the estimated minimum probable obligations, as no other amount within the range was a better estimate. |
Commitments_And_Contingencies_4
Commitments And Contingencies (Pumped-Storage Hydroelectric Facility Breach) (Detail) (Union Electric Company, USD $) | Sep. 30, 2013 |
In Millions, unless otherwise specified | |
Union Electric Company | ' |
Loss Contingencies [Line Items] | ' |
Insurance settlements receivable | $68 |
Commitments_And_Contingencies_5
Commitments And Contingencies (Asbestos-Related Litigation And Tax Exemptions And Credits) (Detail) (USD $) | 9 Months Ended | 1 Months Ended | ||||||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Jul. 31, 2013 | |
Asbestos-Related | Asbestos-Related | Asbestos-Related | Asbestos-Related | Collectibility of Taxes | State and Local Jurisdiction [Member] | State and Local Jurisdiction [Member] | ||
defendant | Union Electric Company | Ameren Illinois Company | Ameren Corporation | Ameren Illinois Company | Collectibility of Taxes | Collectibility of Taxes | ||
lawsuit | lawsuit | lawsuit | lawsuit | customer | Ameren Illinois Company | Ameren Illinois Company | ||
Loss Contingencies [Line Items] | ' | ' | ' | ' | ' | ' | ' | |
Average number of total defendants named | 78 | ' | ' | ' | ' | ' | ' | |
Asbestos-related lawsuits were pending | 85 | [1] | 55 | 63 | 1 | ' | ' | ' |
Range of possible loss, minimum | $15 | $7 | $8 | ' | $1 | ' | ' | |
Range of possible loss maximum | ' | ' | ' | ' | 5 | ' | ' | |
Loss contingency accrual | ' | ' | ' | ' | 1 | ' | ' | |
Percent of allowed cash expenditures in excess of base rates to be recovered through charges assessed to customers | 90.00% | ' | ' | ' | ' | ' | ' | |
Asbestos trust fund balance | 23 | ' | ' | ' | ' | ' | ' | |
Percent of difference to be contributed to the asbestos trust fund if cash expenditures are less than amount included in base electric rates. | 90.00% | ' | ' | ' | ' | ' | ' | |
Public Utilities, Number of Customers | ' | ' | ' | ' | 2,400 | ' | ' | |
Loss Contingency, Damages Awarded, Value | ' | ' | ' | ' | ' | $1 | $4 | |
[1] | Total does not equal the sum of the subsidiary unit lawsuits because some of the lawsuits name multiple Ameren entities as defendants. |
Callaway_Energy_Center_Narrati
Callaway Energy Center (Narrative) (Detail) (Nuclear Plant [Member], USD $) | 9 Months Ended | 12 Months Ended | |
In Millions, unless otherwise specified | Sep. 30, 2013 | Dec. 31, 2012 | Dec. 31, 2011 |
mill | |||
Nuclear Plant [Member] | ' | ' | ' |
Nuclear Waste Matters [Line Items] | ' | ' | ' |
Number of mills charged for NWF fee | 1 | ' | ' |
Settlement payment | $6 | ' | ' |
Assumed life of plant, in years | '40 years | ' | ' |
Annual decommissioning costs included in costs of service | $7 | $7 | $7 |
Missouri Public Service Commission, Requirement to file updated cost study and funding analysis for decommissioning energy center, Period | '3 years | ' | ' |
Retirement_Benefits_Narrative_
Retirement Benefits (Narrative) (Detail) (USD $) | Sep. 30, 2013 |
In Millions, unless otherwise specified | |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' |
Defined benefit plan, estimated future employer contributions in each of the next five years | $475 |
Minimum | ' |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' |
Defined benefit plan, estimated future employer contributions in each of the next five years | 50 |
Maximum | ' |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' |
Defined benefit plan, estimated future employer contributions in each of the next five years | $150 |
Retirement_Benefits_Components
Retirement Benefits (Components Of Net Periodic Benefit Cost) (Detail) (USD $) | 3 Months Ended | 9 Months Ended | ||||||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | ||||
Pension Benefit [Member] | ' | ' | ' | ' | ||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' | ' | ' | ' | ||||
Service cost | $23 | $20 | $69 | $61 | ||||
Interest cost | 40 | 42 | 121 | 125 | ||||
Expected return on plan assets | -54 | -52 | -162 | -156 | ||||
Transition obligation | ' | ' | ' | ' | ||||
Prior service cost (benefit) | -1 | -1 | -3 | -3 | ||||
Actuarial loss | 23 | 19 | 69 | 56 | ||||
Net periodic benefit cost | 31 | [1] | 28 | [1] | 94 | [1] | 83 | [1] |
Postretirement Benefit Costs [Member] | ' | ' | ' | ' | ||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' | ' | ' | ' | ||||
Service cost | 6 | 5 | 17 | 16 | ||||
Interest cost | 11 | 12 | 34 | 36 | ||||
Expected return on plan assets | -16 | -14 | -47 | -42 | ||||
Transition obligation | ' | 1 | ' | 1 | ||||
Prior service cost (benefit) | -1 | -1 | -3 | -3 | ||||
Actuarial loss | 2 | 1 | 6 | 3 | ||||
Net periodic benefit cost | $2 | [1] | $4 | [1] | $7 | [1] | $11 | [1] |
[1] | Excludes the EEI plans as they are included in discontinued operations. |
Retirement_Benefits_Summary_Of
Retirement Benefits (Summary Of Benefit Plan Costs Incurred) (Detail) (USD $) | 3 Months Ended | 9 Months Ended | ||||||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | ||||
Pension Benefit [Member] | ' | ' | ' | ' | ||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' | ' | ' | ' | ||||
Net periodic benefit cost | $31 | [1] | $28 | [1] | $94 | [1] | $83 | [1] |
Pension Benefit [Member] | Union Electric Company | ' | ' | ' | ' | ||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' | ' | ' | ' | ||||
Net periodic benefit cost | 18 | 16 | 54 | 48 | ||||
Pension Benefit [Member] | Ameren Illinois Company | ' | ' | ' | ' | ||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' | ' | ' | ' | ||||
Net periodic benefit cost | 10 | 9 | 31 | 27 | ||||
Pension Benefit [Member] | Other | ' | ' | ' | ' | ||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' | ' | ' | ' | ||||
Net periodic benefit cost | 3 | 3 | 9 | 8 | ||||
Postretirement Benefits [Member] | ' | ' | ' | ' | ||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' | ' | ' | ' | ||||
Net periodic benefit cost | 2 | [1] | 4 | [1] | 7 | [1] | 11 | [1] |
Postretirement Benefits [Member] | Union Electric Company | ' | ' | ' | ' | ||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' | ' | ' | ' | ||||
Net periodic benefit cost | 2 | 2 | 7 | 7 | ||||
Postretirement Benefits [Member] | Ameren Illinois Company | ' | ' | ' | ' | ||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' | ' | ' | ' | ||||
Net periodic benefit cost | 1 | [2] | 1 | 1 | [2] | 3 | ||
Postretirement Benefits [Member] | Other | ' | ' | ' | ' | ||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ' | ' | ' | ' | ||||
Net periodic benefit cost | $1 | [2] | $1 | $1 | [2] | $1 | ||
[1] | Includes amounts for Ameren registrants and nonregistrant subsidiaries, but excludes the EEI plans as they are included in discontinued operations. | |||||||
[2] | Less than $1 million. |
Segment_Information_Narrative_
Segment Information (Narrative) (Detail) | 9 Months Ended |
Sep. 30, 2013 | |
Segment | |
Segment Reporting [Abstract] | ' |
Number of reportable segments | 3 |
Segment_Information_Schedule_O
Segment Information (Schedule Of Segment Reporting Information By Segment) (Detail) (USD $) | 3 Months Ended | 9 Months Ended | ||||||
In Millions, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Dec. 31, 2012 | |||
Segment Reporting Information [Line Items] | ' | ' | ' | ' | ' | |||
External revenues | $1,638 | $1,709 | $4,516 | $4,523 | ' | |||
Continuing Operations | 305 | 309 | 464 | 507 | ' | |||
Total assets | 22,385 | ' | 22,385 | ' | 22,219 | |||
Union Electric Company | ' | ' | ' | ' | ' | |||
Segment Reporting Information [Line Items] | ' | ' | ' | ' | ' | |||
External revenues | 1,088 | 1,059 | 2,760 | 2,583 | ' | |||
Intersegment revenues | 5 | 5 | 18 | 16 | ' | |||
Continuing Operations | 238 | 236 | 362 | 400 | ' | |||
Total assets | 13,231 | ' | 13,231 | ' | 13,043 | |||
Ameren Illinois Company | ' | ' | ' | ' | ' | |||
Segment Reporting Information [Line Items] | ' | ' | ' | ' | ' | |||
External revenues | 547 | 647 | 1,744 | 1,935 | ' | |||
Intersegment revenues | ' | 1 | 3 | 1 | ' | |||
Continuing Operations | 77 | 71 | 139 | 130 | ' | |||
Total assets | 7,439 | ' | 7,439 | ' | 7,282 | |||
Other Segment [Member] | ' | ' | ' | ' | ' | |||
Segment Reporting Information [Line Items] | ' | ' | ' | ' | ' | |||
External revenues | 3 | 3 | 12 | 5 | ' | |||
Intersegment revenues | 1 | ' | 2 | 2 | ' | |||
Continuing Operations | -10 | 2 | -37 | -23 | ' | |||
Total assets | 1,375 | ' | 1,375 | ' | 1,228 | |||
Intersegment Elimination [Member] | ' | ' | ' | ' | ' | |||
Segment Reporting Information [Line Items] | ' | ' | ' | ' | ' | |||
External revenues | ' | ' | ' | ' | ' | |||
Intersegment revenues | -6 | -6 | -23 | -19 | ' | |||
Continuing Operations | ' | ' | ' | ' | ' | |||
Total assets | -1,055 | ' | -1,055 | ' | -934 | |||
Segment, Continuing Operations [Member] | ' | ' | ' | ' | ' | |||
Segment Reporting Information [Line Items] | ' | ' | ' | ' | ' | |||
External revenues | 1,638 | 1,709 | 4,516 | 4,523 | ' | |||
Continuing Operations | 305 | 309 | 464 | 507 | ' | |||
Total assets | $20,990 | [1] | ' | $20,990 | [1] | ' | $20,619 | [1] |
[1] | Excludes “Assets of discontinued operations.†See Note 2 - Divestiture Transactions and Discontinued Operations for additional information. |