Disaggregation of sales - Schedule of Disaggregates of Net Sales of our Component Products and Real Estate Management and Development Segments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation Of Revenue [Line Items]
Net sales	$ 2,104.8	$ 1,921.7	$ 2,222.5
Component products
Disaggregation Of Revenue [Line Items]
Net sales	145.9	161.3	166.6
Component products | Security Products
Disaggregation Of Revenue [Line Items]
Net sales	115.2	121.2	114.5
Component products | Marine Components
Disaggregation Of Revenue [Line Items]
Net sales	30.7	40.1	52.1
Real estate management and development
Disaggregation Of Revenue [Line Items]
Net sales	71.8	93.9	125.7
Real estate management and development | Land sales
Disaggregation Of Revenue [Line Items]
Net sales	71.5	92.6	120.9
Real estate management and development | Utility and other
Disaggregation Of Revenue [Line Items]
Net sales	$ 0.3	$ 1.3	1.2
Real estate management and development | Water delivery
Disaggregation Of Revenue [Line Items]
Net sales			$ 3.6