Employee Benefit Plans US Pension Assets, Fair Value Measurement by Input Level (Details) - UNITED STATES - Pension Plan - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Equity Funds
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	$ 445.8	$ 463.1
Equity Funds | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	55.0	57.4
Equity Funds | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Equity Funds | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Equity Funds | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	390.8	405.7
U.S. Government and Agencies
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	256.7	215.7
U.S. Government and Agencies | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	215.9	194.0
U.S. Government and Agencies | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	40.8	21.7
U.S. Government and Agencies | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
U.S. Government and Agencies | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Corporate
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	130.0	129.6
Corporate | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Corporate | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Corporate | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Corporate | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	130.0	129.6
Foreign Emerging Market Fixed Income Securities
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	27.9	54.0
Foreign Emerging Market Fixed Income Securities | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Foreign Emerging Market Fixed Income Securities | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Foreign Emerging Market Fixed Income Securities | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Foreign Emerging Market Fixed Income Securities | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	27.9	54.0
Opportunistic Credits
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	150.6	132.3
Opportunistic Credits | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Opportunistic Credits | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Opportunistic Credits | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Opportunistic Credits | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	150.6	132.3
Real Estate
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	162.8	164.2
Real Estate | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Real Estate | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Real Estate | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Real Estate | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	162.8	164.2
Private Equity Direct Investments
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	68.5	74.5
Private Equity Direct Investments | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Private Equity Direct Investments | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Private Equity Direct Investments | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Private Equity Direct Investments | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	68.5	74.5
Private Equity Funds of Funds
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	40.7	47.6
Private Equity Funds of Funds | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Private Equity Funds of Funds | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Private Equity Funds of Funds | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Private Equity Funds of Funds | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	40.7	47.6
Cash Equivalents
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	16.0	20.5
Cash Equivalents | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	16.0	20.5
Cash Equivalents | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Cash Equivalents | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Cash Equivalents | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Total Invested Assets
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	1,299.0	1,301.5
Total Invested Assets | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	286.9	271.9
Total Invested Assets | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	40.8	21.7
Total Invested Assets | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Total Invested Assets | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	$ 971.3	$ 1,007.9