XML 148 R62.htm IDEA: XBRL DOCUMENT v3.20.2

Summary of Significant Accounting Policies - Leases (Details) $ in Millions	Sep. 30, 2020 USD ($)
Leases
Finance lease under PPA	$ 500
Operating lease under PPA	$ 174

X

- Definition

Finance lease under PPA

+ References

No definition available.

+ Details

Name:	tve_FinanceLeaseUnderPPA
Namespace Prefix:	tve_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Leases [Line Items]

+ References

No definition available.

+ Details

Name:	tve_LeasesLineItems
Namespace Prefix:	tve_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Operating lease under PPA

+ References

No definition available.

+ Details

Name:	tve_OperatingLeaseUnderPPA
Namespace Prefix:	tve_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant