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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Pooled Subscriber Assets And Related Deferred Revenue, Useful Life

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Standard chargeback period from dealer for monitoring service cancellations

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- Definition

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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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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- 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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The current cash, cash equivalents and investments that are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes current cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal.

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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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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, 2022 USD ($) country	Sep. 30, 2021 USD ($)	Sep. 30, 2020 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%
Restricted cash	$ 35	$ 6
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	$ 295	275	$ 274
Foreign currency transaction gains (losses)	$ 49	$ 56	$ (32)
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