Revenue - disaggregation of sales - Schedule of Disaggregates of Net Sales of our Component Products and Real Estate Management and Development Segments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Disaggregation Of Revenue [Line Items]
Net sales	$ 540.4	$ 559.7	$ 1,079.0	$ 1,090.3
Component products
Disaggregation Of Revenue [Line Items]
Net sales	40.3	35.9	80.6	73.9
Component products | Security Products
Disaggregation Of Revenue [Line Items]
Net sales	30.7	28.2	60.9	58.1
Component products | Marine Components
Disaggregation Of Revenue [Line Items]
Net sales	$ 9.6	$ 7.7	$ 19.7	$ 15.8