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Goodwill and Other Intangibles - Summary of Intangible Assets Acquired (Detail) $ in Millions | 9 Months Ended
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Sep. 30, 2021 USD ($)
Acquired Finite And Indefinite Lived Intangible Assets [Line Items] |
Total subject to amortization | $ 294.9
Weighted-average amortization period | 27 years
Customer Relationships |
Acquired Finite And Indefinite Lived Intangible Assets [Line Items] |
Total subject to amortization | $ 221.4
Weighted-average amortization period | 24 years
Permits |
Acquired Finite And Indefinite Lived Intangible Assets [Line Items] |
Total subject to amortization | $ 63.0
Weighted-average amortization period | 40 years
Trade names |
Acquired Finite And Indefinite Lived Intangible Assets [Line Items] |
Total subject to amortization | $ 10.5
Weighted-average amortization period | 9 years

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- Definition Acquired finite and indefinite lived intangible assets. + References No definition available. + Details
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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 Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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