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Acquisitions - Summary of Changes to Goodwill Balance (Detail) $ in Millions	12 Months Ended
	Sep. 30, 2019 USD ($)
Goodwill [Line Items]
Ending balance	$ 416.1
Counsyl Inc [Member]
Goodwill [Line Items]
Beginning balance	94.9
Fair value adjustment to equipment	0.7
Intangible adjustment	2.9
Working capital adjustment	(1.1)
Change in deferred tax liability	1.9
Ending balance	$ 99.3

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- Definition

Goodwill adjustment to deferred tax assets liabilities.

+ References

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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
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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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Amount of transfers into (out 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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