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Summary of Significant Accounting Policies Summary of Significant Accounting Policies - General (Details) People in Millions, $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2018 USD ($) People Customers | Sep. 30, 2017 USD ($)
Population of Service Area |  |
Total possible amount of BLEU payments | $ 166 |
Loans and other long-term receivables, net (including current portion) | $ 123 | $ 107
Population of TVA's service area (number of people) | People | 10 |
Maximum original maturity | 3 months |
Allowance for uncollectible accounts - loans |  | 1
Number of customers for whom unbilled revenues are estimated | Customers | 5 |
Revenue Capitalized During Pre-Commercial Operations | $ 11 | 22
Fuel Cost Capitalized During Pre-Commercial Operations | 19 | 14
Recorded cost for emission allowances granted by the Environmental Protection Agency | 0 |
Payments attributable to blended low-enriched uranium fuel currently in use | 165 |
BLEU fuel obligation | 1 |
Total |  |
Population of Service Area |  |
Discounts reducing electricity sales | 46 | 46
MLGW |  |
Population of Service Area |  |
Deferred revenue, revenue recognized | $ 10 | $ 100

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- Definition The liability established for payments due that are attributable to blended low-enriched uranium fuel that has been used. + References No definition available. + Details
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- Definition Fuel costs incurred during pre-commercial generation capitalized to project costs. + References No definition available. + Details
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- Definition Payments attributable to blended low-enriched uranium fuel program + References No definition available. + Details
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- Definition The population of the company's service area. + References No definition available. + Details
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- Definition Recorded cost for emission allowances granted by the Environmental Protection Agency + References No definition available. + Details
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X
- Definition Estimates of revenue realized from pre-commercial generation based on the guidance provided by FERC regulations. The calculated revenue is capitalized to offset project costs and is included in revenue as a contra-revenue amount + References No definition available. + Details
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- Definition Total of past and projected future payments that TVA may make to the DOE over the duration of the BLEU fuel program, from inception to termination. It includes the amounts paid out, plus an estimated amount related to possible future payments that may be payable to the DOE until the time that the BLEU fuel program ceases to be in effect. + References No definition available. + Details
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- Definition A valuation allowance relating to a written agreement to receive money (at a specified future date(s) more than one year from the reporting date, consisting of principal as well as any accrued interest) for the portion that is expected to be uncollectible. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.4) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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