Debt and Other Financing Arrangements - Financing Arrangements (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Available	$ 1,500
Liquidity	2,100
Cash	631
Unamortized debt issuance costs	92	$ 82
Long-term Debt	5,111	5,171
Other assets
Debt Instrument [Line Items]
Unamortized debt issuance costs	15	$ 17
Tenneco Inc. revolving credit agreement
Debt Instrument [Line Items]
Available	1,500
Long-term Debt	0
Tenneco Inc. Term Loan A
Debt Instrument [Line Items]
Available	0
Tenneco Inc. Term Loan B
Debt Instrument [Line Items]
Available	0
Subsidiaries’ credit agreements
Debt Instrument [Line Items]
Available	$ 0

Liquidity

No definition available.

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
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- 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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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ 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
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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+ Details

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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-Name Accounting Standards Codification
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- Details

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