Reporting unit carrying value of goodwill.

No definition available.

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- Definition

Reporting unit estimate fair value of goodwill.

+ References

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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Goodwill and Intangible Assets - Goodwill - Additional Information (Details) - USD ($)	6 Months Ended	12 Months Ended
	Mar. 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Goodwill [Line Items]
Reporting unit percentage of fair value in excess of carrying value	2.00%
Reporting unit, estimate fair value of goodwill	$ 951,000,000
Reporting unit, amount of fair value in excess of carrying amount	936,000,000
Goodwill impairment	0	$ 0	$ 0	$ 0
Technology-Based Intangible Assets \| Cost of Revenues
Goodwill [Line Items]
Amortization expense		8,300,000	8,500,000	6,600,000
Patent \| Cost of Revenues
Goodwill [Line Items]
Amortization expense			22,000,000	1,200,000
Customer Relationships \| Operating Expenses
Goodwill [Line Items]
Amortization expense		$ 12,600,000	$ 12,500,000	$ 8,800,000
Minimum
Goodwill [Line Items]
Reporting unit percentage of fair value in excess of carrying value		50.00%
Reporting unit, amount of fair value in excess of carrying amount	$ 15,000,000