Income Tax Matters - Income Tax Provision by Region (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Domestic	$ (7.0)	$ (4.4)
Foreign	(0.5)	(0.5)
Total	$ (7.5)	$ (4.9)