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Retirement and Postretirement Plans - Allocation of Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pension
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	$ 396.6	$ 525.6	$ 549.4
Pension | Level 1, 2 and 3
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	205.5	251.9
Pension | Level 1, 2 and 3 | Cash and cash equivalents
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	12.6	5.8
Pension | Level 1, 2 and 3 | U.S government and agency securities
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	36.3	59.8
Pension | Level 1, 2 and 3 | Corporate bonds
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets		39.8
Pension | Level 1, 2 and 3 | Mutual fund - equities
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	80.9	83.3
Pension | Level 1, 2 and 3 | Mutual fund - fixed income
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	12.5	12.2
Pension | Level 1, 2 and 3 | Mutual fund - tactical tilt
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	10.8	10.6
Pension | Level 1, 2 and 3 | Equity securities
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.5
Pension | Level 1, 2 and 3 | Real estate
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	29.7	14.1
Pension | Level 1, 2 and 3 | Private debt
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	22.2	25.7
Pension | Level 1, 2 and 3 | Other
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets		0.6
Pension | Level 1
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	144.3	156.8
Pension | Level 1 | Cash and cash equivalents
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	3.3	0.0
Pension | Level 1 | U.S government and agency securities
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	36.3	50.7
Pension | Level 1 | Corporate bonds
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets		0.0
Pension | Level 1 | Mutual fund - equities
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	80.9	83.3
Pension | Level 1 | Mutual fund - fixed income
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	12.5	12.2
Pension | Level 1 | Mutual fund - tactical tilt
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	10.8	10.6
Pension | Level 1 | Equity securities
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.5
Pension | Level 1 | Real estate
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.0	0.0
Pension | Level 1 | Private debt
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.0	0.0
Pension | Level 1 | Other
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets		0.0
Pension | Level 2
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	9.3	55.3
Pension | Level 2 | Cash and cash equivalents
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	9.3	5.8
Pension | Level 2 | U.S government and agency securities
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.0	9.1
Pension | Level 2 | Corporate bonds
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets		39.8
Pension | Level 2 | Equity securities
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.0
Pension | Level 2 | Real estate
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.0	0.0
Pension | Level 2 | Private debt
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.0	0.0
Pension | Level 2 | Other
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets		0.6
Pension | Level 3
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	51.9	39.8
Pension | Level 3 | Cash and cash equivalents
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.0
Pension | Level 3 | U.S government and agency securities
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.0
Pension | Level 3 | Equity securities
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.0
Pension | Level 3 | Real estate
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	29.7	14.1
Pension | Level 3 | Private debt
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	22.2	25.7
Pension | Assets measured at net asset value
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	$ 191.1	$ 273.7
Redemption period	90 days	90 days
Postretirement
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	$ 49.4	$ 53.8	$ 59.2
Postretirement | Level 1, 2 and 3
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	25.3	26.6
Postretirement | Level 1, 2 and 3 | Cash and cash equivalents
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	3.6	2.2
Postretirement | Level 1, 2 and 3 | Mutual fund - equities
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	11.9	13.5
Postretirement | Level 1, 2 and 3 | Mutual fund - fixed income
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	6.6	7.3
Postretirement | Level 1, 2 and 3 | Mutual fund - tactical tilt
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	2.3	2.5
Postretirement | Level 1, 2 and 3 | Real estate
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.9	1.1
Postretirement | Level 1
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	25.3	26.6
Postretirement | Level 1 | Cash and cash equivalents
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	3.6	2.2
Postretirement | Level 1 | Mutual fund - equities
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	11.9	13.5
Postretirement | Level 1 | Mutual fund - fixed income
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	6.6	7.3
Postretirement | Level 1 | Mutual fund - tactical tilt
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	2.3	2.5
Postretirement | Level 1 | Real estate
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	0.9	1.1
Postretirement | Assets measured at net asset value
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Total Assets	$ 24.1	$ 27.2

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