Estimated Useful Life Of Dealer Intangible Assets

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Financial Statement Details [Line Items]

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Interest percentage minimum for investments in partially-owned affiliates to be accounted for by the equity method.

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- Definition

Non-Pooled Subscriber Assets And Related Deferred Revenue, Useful Life

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- Definition

Non-standard chargeback period from dealer for monitoring service cancellations

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- Definition

Pooled Subscriber Assets And Related Deferred Revenue, Useful Life

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- Definition

Standard chargeback period from dealer for monitoring service cancellations

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- Definition

Amount, before tax, of realized and unrealized gain (loss) from foreign currency transaction.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
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- Definition

The number of countries in which the entity operates as of balance sheet date.

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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No definition available.

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- Definition

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Summary of Significant Accounting Policies (Details) $ in Millions	12 Months Ended
	Sep. 30, 2023 USD ($) country	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Financial Statement Details [Line Items]
Number of countries in which entity operates \| country	150
Interest percentage minimum for investments in partially owned affiliates to be accounted for by equity method	20.00%
Pooled subscriber assets and related deferred revenue, useful life	12 years
Non-pooled subscriber assets and related deferred revenue, useful life	15 years
Standard chargeback period from dealer for monitoring service cancellations	6 months
Non-standard chargeback period from dealer for monitoring service cancellations	12 months
Research and development expense	$ 320	$ 295	$ 275
Foreign currency transaction gains (losses)	$ 28	$ 49	$ 56
Restricted Stock
Financial Statement Details [Line Items]
Vesting period	3 years
Employee Stock Option
Financial Statement Details [Line Items]
Expiration period for stock options	10 years
Minimum
Financial Statement Details [Line Items]
Estimated useful life of dealer intangible assets	12 years
Minimum \| Performance Shares
Financial Statement Details [Line Items]
Vesting period	1 year
Minimum \| Employee Stock Option
Financial Statement Details [Line Items]
Vesting period	2 years
Maximum
Financial Statement Details [Line Items]
Estimated useful life of dealer intangible assets	15 years
Maximum \| Performance Shares
Financial Statement Details [Line Items]
Vesting period	3 years
Maximum \| Employee Stock Option
Financial Statement Details [Line Items]
Vesting period	3 years
Building And Improvements \| Minimum
Financial Statement Details [Line Items]
Estimated useful lives	3 years
Building And Improvements \| Maximum
Financial Statement Details [Line Items]
Estimated useful lives	40 years
Subscriber Systems \| Maximum
Financial Statement Details [Line Items]
Estimated useful lives	15 years
Machinery and Equipment \| Minimum
Financial Statement Details [Line Items]
Estimated useful lives	3 years
Machinery and Equipment \| Maximum
Financial Statement Details [Line Items]
Estimated useful lives	15 years