Property, Plant and Equipment (Tables)

12 Months Ended

Sep. 30, 2024

Property, Plant and Equipment [Abstract]

Schedule of Property, Plant and Equipment

The estimated useful lives of property, plant and equipment categories are as follows:

Category	Estimated Useful Life
Land and improvements	Land, unlimited; improvements, 15-25 years
Mineral reserves	Based on depletion
Buildings	5 - 39 years
Plants	3 - 20 years
Construction equipment	3 - 10 years
Furniture and fixtures	5 - 10 years
Leasehold improvements	The shorter of 15 years or the remaining lease term

Property, plant and equipment at September 30, 2024 and 2023 consisted of the following (in thousands):

	September 30,
	2024		2023
Construction equipment	$	570,044	$	447,467
Plants	255,214		208,708
Land and improvements	94,182		76,396
Mineral reserves	69,334		69,405
Buildings	39,838		36,885
Furniture and fixtures	8,616		7,538
Leasehold improvements	1,268		1,268
Total property, plant and equipment, gross	1,038,496		847,667
Accumulated depreciation, depletion and amortization	(426,842)		(358,462)
Construction in progress	18,270		15,890
Total property, plant and equipment, net	$	629,924	$	505,095