XML 70 R75.htm IDEA: XBRL DOCUMENT
v3.19.3

Debt and Other Obligations Debt and Other Obligations - General (Details) - USD ($) $ in Millions | Sep. 30, 2019 | Sep. 30, 2013 | Aug. 09, 2013 | Sep. 30, 2012 | Jan. 17, 2012
--- | --- | --- | --- | --- | ---
Debt Instrument |  |  |  |  |
Interest rate |  |  |  |  | 7.10%
Debt ceiling | $ 30,000 |  |  |  |
Face Amount | 40 |  |  |  | $ 100
Holdco |  |  |  |  |
Debt Instrument |  |  |  |  |
Face Amount |  |  |  | $ 100 |
Holdco balloon payment upon maturity | $ 10 |  |  |  |
SCCG |  |  |  |  |
Debt Instrument |  |  |  |  |
Interest rate |  |  | 3.846% |  |
Face Amount |  | $ 360 | $ 360 |  |

X
- Definition The cap on the amount of bonds the company can have outstanding. + References No definition available. + Details
Name: | tve_DebtCeiling
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + 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 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentPeriodicPaymentTermsBalloonPaymentToBePaid
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=tve_HoldcoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=tve_SCCGMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |