XML 86 R62.htm IDEA: XBRL DOCUMENT v3.8.0.1

Risk Management Activities and Derivative Transactions Counterparty Credit Risk (Details) $ in Millions	Dec. 31, 2017 USD ($) merchants megawatts
Derivative
Number of active future commission merchants | merchants	2
Total derivatives not subject to master netting or similar arrangement | $	$ 16	[1]
Megawatts of Power Purchase Agreement
Derivative
Megawatts | megawatts	440
[1] There are no derivative contracts subject to a master netting arrangement or similar agreement that are not offset in the consolidated balance sheets.

X

- Definition

Megawatts of summer net capability

+ References

No definition available.

+ Details

Name:	tve_Megawatts
Namespace Prefix:	tve_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Number of active future commission merchants to clear commodity contracts.

+ References

No definition available.

+ Details

Name:	tve_NumberOfActiveFutureCommissionMerchants
Namespace Prefix:	tve_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226052-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

+ Details

Name:	us-gaap_DerivativeAssetNotSubjectToMasterNettingArrangement
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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_DerivativeLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_LongTermContractForPurchaseOfElectricPowerDomain
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: