Pensions and Postretirement Benefits Other Than Pensions (Schedule of Fair Values of Company's Pension Plan Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Defined benefit plan, fair value of pension plan assets	$ 2,145.7	$ 2,051.6
Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	4.7	3.3
Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	1,497.5	1,450.9
Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	120.9	109.8
Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	512.2	479.2
Registered mutual funds, fixed income specialty [Member]
Defined benefit plan, fair value of pension plan assets	96.1	105.0
Registered mutual funds, fixed income specialty [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Registered mutual funds, fixed income specialty [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Registered mutual funds, fixed income specialty [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
U.S. Government and Agency Obligations [Member]
Defined benefit plan, fair value of pension plan assets	355.7	323.6
U.S. Government and Agency Obligations [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
U.S. Government and Agency Obligations [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	355.7	323.6
U.S. Government and Agency Obligations [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Corporate and Non-U.S. Bonds [Member]
Defined benefit plan, fair value of pension plan assets	1,079.5	1,065.7
Corporate and Non-U.S. Bonds [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Corporate and Non-U.S. Bonds [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	1,079.5	1,065.7
Corporate and Non-U.S. Bonds [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Asset-Backed And Mortgage-Backed Securities [Member]
Defined benefit plan, fair value of pension plan assets	12.5	12.5
Asset-Backed And Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Asset-Backed And Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	12.5	12.5
Asset-Backed And Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Commingled Funds - Fixed Income Specialty [Member]
Defined benefit plan, fair value of pension plan assets	75.0	61.7
Commingled Funds - Fixed Income Specialty [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Commingled Funds - Fixed Income Specialty [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Commingled Funds - Fixed Income Specialty [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Other Fixed Income [Member]
Defined benefit plan, fair value of pension plan assets	31.2	29.3
Other Fixed Income [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Other Fixed Income [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Other Fixed Income [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	31.2	29.3
Derivative [Member]
Defined benefit plan, fair value of pension plan assets	5.9	(1.5)
Derivative [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Derivative [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	5.9	(1.5)
Derivative [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Derivative [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Real Estate Funds [Member]
Defined benefit plan, fair value of pension plan assets		0.9
Real Estate Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets		0.0
Real Estate Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets		0.0
Real Estate Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets		0.9
Real Estate Funds [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets		0.0
Other Defined Benefit [Member]
Defined benefit plan, fair value of pension plan assets	89.7	79.6
Other Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Other Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Other Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	89.7	79.6
Other Defined Benefit [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Cash and Cash Equivalents [Member]
Defined benefit plan, fair value of pension plan assets	48.6	53.9
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	4.7	3.3
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	43.9	50.6
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Cash and Cash Equivalents [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Registered mutual funds, equity specialty [Member]
Defined benefit plan, fair value of pension plan assets	78.7	68.0
Registered mutual funds, equity specialty [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Registered mutual funds, equity specialty [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Registered mutual funds, equity specialty [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Commingled funds, equity specialty [Member]
Defined benefit plan, fair value of pension plan assets	262.4	244.5
Commingled funds, equity specialty [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Commingled funds, equity specialty [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Commingled funds, equity specialty [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Receivables and Payables
Defined benefit plan, fair value of pension plan assets	10.4	8.4
Registered mutual funds, equity specialty [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	78.7	68.0
Equity Securities [Member]
Defined benefit plan, fair value of pension plan assets	341.1	312.5
Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Equity Securities [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	341.1	312.5
Commingled funds, equity specialty [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	262.4	244.5
Fixed Income Investments [Member]
Defined benefit plan, fair value of pension plan assets	1,650.0	1,597.8
Fixed Income Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Fixed Income Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Defined benefit plan, fair value of pension plan assets	1,447.7	1,401.8
Fixed Income Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Defined benefit plan, fair value of pension plan assets	31.2	29.3
Fixed Income Investments [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	171.1	166.7
Fixed Income Investments [Member] | Registered mutual funds, fixed income specialty [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	96.1	105.0
Fixed Income Investments [Member] | U.S. Government and Agency Obligations [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Fixed Income Investments [Member] | Corporate and Non-U.S. Bonds [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Fixed Income Investments [Member] | Asset-Backed And Mortgage-Backed Securities [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Fixed Income Investments [Member] | Commingled Funds - Fixed Income Specialty [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	75.0	61.7
Fixed Income Investments [Member] | Other Fixed Income [Member] | Net Assets, Segment [Member]
Defined benefit plan, fair value of pension plan assets	0.0	0.0
Defined Benefit Plan Fair Value of Plan Assets Measured Using Net Asset Value [Member]
Defined benefit plan, fair value of pension plan assets	$ 2,135.3	$ 2,043.2