Stockholders' Equity - Changes in Each Component of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ (81.3)
Net current-period other comprehensive income (loss)	(2.8)	$ 0.6
Ending balance	(84.1)
Actuarial Losses
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(69.7)	(68.6)
Other comprehensive income (loss) before reclassifications	0.1	(0.4)
Amounts reclassified from accumulated other comprehensive loss	0.5	0.4
Net current-period other comprehensive income (loss)	0.6	0.0
Ending balance	(69.1)	(68.6)
Prior Service Costs
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(2.0)	(2.0)
Other comprehensive income (loss) before reclassifications	0.0	0.0
Amounts reclassified from accumulated other comprehensive loss	0.0	0.0
Net current-period other comprehensive income (loss)	0.0	0.0
Ending balance	(2.0)	(2.0)
Currency Translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(10.1)	(16.0)
Other comprehensive income (loss) before reclassifications	(3.9)	1.5
Amounts reclassified from accumulated other comprehensive loss	0.0	0.0
Net current-period other comprehensive income (loss)	(3.9)	1.5
Ending balance	(14.0)	(14.5)
Interest Rate Swaps
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0.5	2.6
Other comprehensive income (loss) before reclassifications	1.2	(0.4)
Amounts reclassified from accumulated other comprehensive loss	(0.7)	(0.5)
Net current-period other comprehensive income (loss)	0.5	(0.9)
Ending balance	1.0	1.7
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(81.3)	(84.0)
Other comprehensive income (loss) before reclassifications	(2.6)	0.7
Amounts reclassified from accumulated other comprehensive loss	(0.2)	(0.1)
Net current-period other comprehensive income (loss)	(2.8)	0.6
Ending balance	$ (84.1)	$ (83.4)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

Name:	us-gaap_AOCIAttributableToParentNetOfTaxRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-14A

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-11

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (g)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (h)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(30)(a)(4))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(a)(3))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-14

+ Details

Name:	us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

+ References

+ Details

Name:	us-gaap_OciBeforeReclassificationsNetOfTaxAttributableToParent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount after tax of other comprehensive income (loss) attributable to parent entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 810
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 19
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481231/810-10-45-19

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 20
-SubTopic 10
-Topic 810
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481231/810-10-45-20

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (c)(3)
-SubTopic 10
-Topic 810
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481203/810-10-50-1A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-1B

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-1A

+ Details

Name:	us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

+ References

+ Details

Name:	us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedDefinedBenefitPlansAdjustmentNetPriorServiceCostCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedTranslationAdjustmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedOtherComprehensiveIncomeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: