Union Pension Plan (Tables)

12 Months Ended

Dec. 31, 2023

Retirement Benefits [Abstract]

Summary of Multiple Employer Pension Plans

Multiple Employer Pension Plans:

Pension Fund	EIN	Pension Protection Act Zone Status as of December 31,		FIP/RP Status	Contributions by Company for the year ended						Surcharge Imposed	Expiration Date of Collective Bargaining Agreement
		2023	2022		2023		2022		2021
Midwest Operating Engineers  Local Union No. 150 Pension Trust Fund	36-6140097	Green 3/31/2023	Green 3/31/2022	None	$	2.8	$	2.4	$	2.2	No	5/31/2024
Operating Engineers Local  Union No. 324 Pension Fund	38-1900637	Red 4/30/2023	Red 4/30/2022	Implemented		1.6		1.2		0.9	Yes	9/30/2024
All Other Multiemployer Pension Plans (1)						1.5		1.2		0.8		Various
Total					$	5.9	$	4.8	$	3.9

(1) All Other Multiemployer Pension Plans includes 12 plans, none of which are individually significant when considering contributions to the plan, severity of the underfunded status or other factors.