Business Combination, Contingent Consideration Arrangements Term

No definition available.

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- Definition

Business combination recognized identifiable assets acquired and liabilities assumed other net assets.

+ References

No definition available.

+ Details

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Namespace Prefix:	alsn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

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-Publisher FASB
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-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
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+ Details

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- Definition

Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

+ References

+ Details

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The amount of inventory recognized as of the acquisition date.

+ References

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+ Details

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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

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+ Details

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Balance Type:	debit
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- Definition

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.

+ References

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-Publisher FASB
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+ Details

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Balance Type:	debit
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
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- Details

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- Details

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- Details

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Acquisitions - Additional Information (Details) - USD ($) $ in Millions				9 Months Ended
	Sep. 09, 2019	Apr. 16, 2019	Apr. 12, 2019	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Business Acquisition [Line Items]
Payments to acquire businesses				$ 232	$ 0
Goodwill				$ 2,040		$ 1,941
Walker Die Casting
Business Acquisition [Line Items]
Payments to acquire businesses	$ 103
Pre-existing accounts payable	4
Preliminary purchase price	99
Property, plant and equipment	53
Goodwill	21
Inventory	18
Intangible assets	4
Other net assets	3
Walker Die Casting \| Customer Relationships
Business Acquisition [Line Items]
Intangible assets	3
Walker Die Casting \| Trade name
Business Acquisition [Line Items]
Intangible assets	$ 1
AxleTech Electric Vehicle Systems Division
Business Acquisition [Line Items]
Payments to acquire businesses		$ 124
Property, plant and equipment		1
Goodwill		66
Inventory		1
Intangible assets		56
AxleTech Electric Vehicle Systems Division \| In Process Research and Development
Business Acquisition [Line Items]
Intangible assets		50
AxleTech Electric Vehicle Systems Division \| Customer Relationships
Business Acquisition [Line Items]
Intangible assets		3
AxleTech Electric Vehicle Systems Division \| Developed Technology
Business Acquisition [Line Items]
Intangible assets		$ 3
Vantage Power Limited
Business Acquisition [Line Items]
Payments to acquire businesses			$ 9
Additional payment amount			$ 8
Payment term			3 years