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Acquisitions - Summary of Changes to Goodwill Balance (Detail) $ in Millions | 3 Months Ended
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Dec. 31, 2018 USD ($)
Goodwill [Line Items] |
Ending balance | $ 413.2
Counsyl Inc [Member] |
Goodwill [Line Items] |
Beginning balance | 94.9
Fair value adjustment to equipment | 0.7
Intangible adjustment | 0.9
Working capital adjustment | (1.1)
Change in deferred tax liability | (0.3)
Ending balance | $ 95.1

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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