Subsequent Events - Additional Information (Detail) - Subsequent Event [Member]	Jul. 12, 2022 USD ($)
3.875% Notes [Member]
Subsequent Event [Line Items]
Debt instrument, offering date	Jul. 12, 2022
Aggregate principal amount issued	$ 300,000,000
Stated interest rate	3.875%
Debt instrument maturity date	Jul. 12, 2024
Debt instrument, maturity year	2024
5.00% Notes [Member]
Subsequent Event [Line Items]
Debt instrument, offering date	Jul. 12, 2022
Aggregate principal amount issued	$ 300,000,000
Stated interest rate	5.00%
Debt instrument maturity date	Jul. 15, 2052
Debt instrument, maturity year	2052

Debt instrument maturity date year.

No definition available.

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Namespace Prefix:	ck0000096271_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the debt instrument was offered for sale, in YYYY-MM-DD format.

+ References

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-Name Accounting Standards Codification
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
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