XML 62 R50.htm IDEA: XBRL DOCUMENT v3.21.2
Goodwill and Other Intangibles - Summary of Intangible Assets Acquired (Detail)
$ in Millions
9 Months Ended
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