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Goodwill and Intangible Assets - Summary Of Intangible Assets and Related Accumulated (Detail) - USD ($) $ in Millions | 12 Months Ended
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Jun. 30, 2021 | Jun. 30, 2020
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | $ 692.9 | $ 544.2
Accumulated Amortization | (366.6) | (295.9)
Net Book Value | 326.3 | 248.3
Customer relationships |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | 420.4 | 358.5
Accumulated Amortization | (205.6) | (170.5)
Net Book Value | $ 214.8 | $ 188.0
Customer relationships | Minimum [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Original Average Life in Years | 6 years | 6 years
Customer relationships | Maximum [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Original Average Life in Years | 17 years | 15 years
Developed technology |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | $ 184.5 | $ 130.0
Accumulated Amortization | (104.7) | (81.0)
Net Book Value | $ 79.8 | $ 49.0
Developed technology | Minimum [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Original Average Life in Years | 3 years | 3 years
Developed technology | Maximum [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Original Average Life in Years | 16 years | 16 years
Trade names |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | $ 47.4 | $ 32.9
Accumulated Amortization | (29.5) | (22.4)
Net Book Value | $ 17.9 | $ 10.5
Trade names | Minimum [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Original Average Life in Years | 5 years | 5 years
Trade names | Maximum [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Original Average Life in Years | 9 years | 9 years
Backlog and other |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | $ 40.6 | $ 22.8
Accumulated Amortization | (26.8) | (22.0)
Net Book Value | $ 13.8 | $ 0.8
Backlog and other | Minimum [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Original Average Life in Years | 1 year | 1 year
Backlog and other | Maximum [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Original Average Life in Years | 9 years | 9 years

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- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 928 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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