Accounts receivable

No definition available.

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- Definition

Balance of appropriated funds advanced and property transferred to/from the reporting entity by the U.S. government as an investment in its power program.

+ References

No definition available.

+ Details

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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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Period Type:	instant

- 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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Balance Type:	credit
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- Definition

The population of the company's service area.

+ References

No definition available.

+ Details

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- Definition

Population of Service Area [Line Items]

+ 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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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Reimbursements from DOE

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Revenue reduction for energy prepayment

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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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Balance Type:	credit
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- Definition

Amount of allowance for credit loss on financing receivable, classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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- Definition

Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

+ References

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- Definition

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Amount of revenue recognized that was previously reported as deferred or unearned revenue.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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- Details

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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, 2019 USD ($) People	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2014 USD ($)
Population of Service Area
Cash	$ 299	$ 299
Total possible amount of BLEU payments	166
Loans and other long-term receivables, net (including current portion)	$ 120	123
Population of TVA's service area (number of people) \| People	10
Allowance for uncollectible accounts - loans		1
Revenue Capitalized During Pre-Commercial Operations	$ 0	11	$ (22)
Fuel Cost Capitalized During Pre-Commercial Operations		19
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
Reimbursements from DOE	23
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	322	322
Accounts receivable from DOE	6
Appropriation-investment power program	258	258		$ 1,000
Total
Population of Service Area
Discounts reducing electricity sales	$ 4	46
MLGW
Population of Service Area
Deferred revenue, revenue recognized		$ 100