XML 31 R18.htm IDEA: XBRL DOCUMENT v3.23.3
Employee Retirement Plans
9 Months Ended
Sep. 30, 2023
Retirement Benefits [Abstract]  
Employee Retirement Plans Employee Retirement Plans
Total employee retirement plan expense, which includes related administrative expenses, is as follows:
Three Months Ended
September 30,
Nine Months Ended
September 30,
2023202220232022
(in millions)
Defined contribution plans$3.9 $3.4 $11.6 $10.2 
Multiemployer plan0.4 0.4 1.2 1.2 
$4.3 $3.8 $12.8 $11.4