Long-Term Debt - Additional Information (Detail) - USD ($) $ in Millions	Jul. 12, 2022	Mar. 18, 2021
2.40% Notes [Member]
Debt Instrument [Line Items]
Debt instrument, maturity year		2031
Aggregate principal amount issued		$ 400
Stated interest rate		2.40%
Debt instrument maturity date		Mar. 15, 2031
Redeemable principal amount percentage		100.00%
Basis spread on federal funds rate		0.15%
Redeemable principal amount percentage		100.00%
Debt instrument, start date of redemption		Dec. 15, 2030
Debt instrument, offering date		Mar. 18, 2021
3.45% Notes [Member]
Debt Instrument [Line Items]
Debt instrument, maturity year		2051
Aggregate principal amount issued		$ 400
Stated interest rate		3.45%
Debt instrument maturity date		Mar. 15, 2051
Redeemable principal amount percentage		100.00%
Basis spread on federal funds rate		0.20%
Redeemable principal amount percentage		100.00%
Debt instrument, start date of redemption		Sep. 15, 2050
Debt instrument, offering date		Mar. 18, 2021
5.00% Notes [Member]
Debt Instrument [Line Items]
Debt instrument, maturity year	2052
Aggregate principal amount issued	$ 300
Stated interest rate	5.00%
Debt instrument maturity date	Jul. 15, 2052
Redeemable principal amount percentage	100.00%
Basis spread on federal funds rate	30.00%
Redeemable principal amount percentage	100.00%
Debt instrument, start date of redemption	Jan. 15, 2052
Debt instrument, offering date	Jul. 12, 2022
3.875% Notes [Member]
Debt Instrument [Line Items]
Debt instrument, maturity year	2024
Aggregate principal amount issued	$ 300
Stated interest rate	3.875%
Debt instrument maturity date	Jul. 12, 2024
Basis spread on federal funds rate	15.00%
Debt instrument, offering date	Jul. 12, 2022

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

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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-SubTopic 20
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+ Details

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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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Balance Type:	na
Period Type:	instant

- 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

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Period Type:	duration

- Definition

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

+ References

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-Publisher FASB
-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

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

+ References

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+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Start date of debt instrument redemption period, in YYYY-MM-DD format.

+ References

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Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

+ Details

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Period Type:	duration

- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

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Period Type:	duration

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- Details

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