Restructuring and Related Activities (Details) $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($) ft²	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Severance and termination costs	$ 0.4	$ (0.1)	$ 0.4
Lease Restructuring Cost	(1.2)	85.4	6.3
Other Restructuring Costs	0.9	17.1	3.9
Restructuring Charges	$ 0.1	102.4	10.6
Area of Real Estate Property \| ft²	500,000
Non-cash Items [Member]
Restructuring Cost and Reserve [Line Items]
Severance and termination costs	$ 0.0	0.0	0.3
Cash Payments [Member]
Restructuring Cost and Reserve [Line Items]
Severance and termination costs	2.1	7.0	65.3
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	0.6	2.3	$ 9.4	$ 74.6
Lease impairment costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 0.0	$ 0.0

Lease Restructuring Cost

No definition available.

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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

+ Details

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 45
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=109237686&loc=d3e17752-110868

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 230
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-Section 45
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-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
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-URI https://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section S99
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-URI https://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

+ Details

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- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

+ References

+ Details

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