Pension, Health Care and Other Postretirement Benefits - Summary of the Fair Value of the Defined Benefit Pension Plan Assets (Details) - Defined Benefit Pension - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Total investments in fair value hierarchy	$ 356.5	$ 232.1	$ 341.9
Total investments	381.8	343.0	483.6
NAV
Defined Benefit Plan Disclosure [Line Items]
Investments measured at NAV or its equivalent	25.3	110.9	141.7
Level 1
Defined Benefit Plan Disclosure [Line Items]
Total investments in fair value hierarchy	109.7	8.5	13.5
Level 2
Defined Benefit Plan Disclosure [Line Items]
Total investments in fair value hierarchy	246.8	223.6	328.4
Equity investments
Defined Benefit Plan Disclosure [Line Items]
Total investments in fair value hierarchy	133.0	80.1	133.1
Equity investments | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total investments in fair value hierarchy	72.9	8.5	13.5
Equity investments | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total investments in fair value hierarchy	60.1	71.6	119.6
Fixed income investments
Defined Benefit Plan Disclosure [Line Items]
Total investments in fair value hierarchy	188.9	117.6	172.1
Fixed income investments | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total investments in fair value hierarchy	36.8
Fixed income investments | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total investments in fair value hierarchy	152.1	117.6	172.1
Other assets
Defined Benefit Plan Disclosure [Line Items]
Total investments in fair value hierarchy	34.6	34.4	36.7
Other assets | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total investments in fair value hierarchy	$ 34.6	$ 34.4	$ 36.7