Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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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.

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- Definition

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

+ References

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Amount of fair value of reporting unit in excess of carrying amount.

+ References

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Goodwill and Other Intangible Assets—Net - Summary of Number of Reporting Units in Goodwill (Details) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2019 reporting_unit	Mar. 31, 2019 reporting_unit	Dec. 31, 2019 USD ($) reporting_unit	Dec. 31, 2018 USD ($)
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit			3
Goodwill \| $			$ 775	$ 869
Clean Air
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit			3,000,000
Goodwill \| $			$ 22	22
Powertrain
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit			2,000,000
Goodwill \| $			$ 325	388
Ride Performance
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit	1	2	2,000,000
Goodwill \| $			$ 47	67
Motorparts
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit			1,000,000
Goodwill \| $			$ 381	$ 392
Greater Than 10% \| Clean Air
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit			3
Reporting units of fair value exceeds carrying amount \| $			$ 22
Greater Than 10% \| Powertrain
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit			0
Reporting units of fair value exceeds carrying amount \| $			$ 0
Greater Than 10% \| Ride Performance
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit			1
Reporting units of fair value exceeds carrying amount \| $			$ 7
Greater Than 10% \| Motorparts
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit			1
Reporting units of fair value exceeds carrying amount \| $			$ 381
Less Than 10% \| Clean Air
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit			0
Reporting units of fair value exceeds carrying amount \| $			$ 0
Less Than 10% \| Powertrain
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit			2
Reporting units of fair value exceeds carrying amount \| $			$ 325
Less Than 10% \| Ride Performance
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit			1
Reporting units of fair value exceeds carrying amount \| $			$ 40
Less Than 10% \| Motorparts
Goodwill [Line Items]
Number of reporting units with goodwill \| reporting_unit			0
Reporting units of fair value exceeds carrying amount \| $			$ 0