Financial Instruments (Realized Gains and Losses) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Proceeds from sales	$ 35.2	$ 43.3
Realized gross gains on sales	0.1	1.1
Realized gross losses on sales	$ 0.8	$ 0.4