Leases - Schedule of Operating Lease Liability Maturity (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Operating Leases
2023 (3 months remaining)	$ 4.5
2024	18.5
2025	17.0
2026	15.7
2027	16.0
Thereafter	54.4
Total operating lease payments (sublease income)	126.1
Less accreted interest	22.4
Total operating lease liabilities	103.7
Less current operating lease liabilities included in other current liabilities	17.8
Noncurrent operating lease liabilities	85.9	$ 93.5
Sublease Income
2023 (3 months remaining)	(0.4)
2024	(1.7)
2025	(1.7)
2026	(1.7)
2027	(1.7)
Thereafter	(6.0)
Total operating lease payments (sublease income)	(13.2)
Non-cancelable future minimum lease payments under operating leases not yet commenced for 2024	17.2
Non-cancelable future minimum lease payments under operating leases not yet commenced for 2025	33.3
Non-cancelable future minimum lease payments under operating leases not yet commenced for 2026	41.9
Non-cancelable future minimum lease payments under operating leases not yet commenced for 2027	43.2
Non-cancelable future minimum lease payments under operating leases not yet commenced for thereafter	$ 436.5

Lessee, Operating Lease, Liability, Payments, Due After Year Four

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Lessor, Operating Lease, Payment to be Received, after Year Four

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Non Cancelable Future Minimum Lease Payments For Operating Leases Not Yet Commenced, After Year Four

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Non Cancelable Future Minimum Lease Payments For Operating Leases Not Yet Commenced, Year Four

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Non Cancelable Future Minimum Lease Payments For Operating Leases Not Yet Commenced, Year One

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Non Cancelable Future Minimum Lease Payments For Operating Leases Not Yet Commenced, Year Three

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Non Cancelable Future Minimum Lease Payments For Operating Leases Not Yet Commenced, Year Two

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-6

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-6

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Amount of lease payments to be received by lessor for operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479773/842-30-50-12

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Amount of lease payment to be received by lessor for operating lease in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lease payment to be received by lessor for operating lease in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lease payment to be received by lessor for operating lease in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479773/842-30-50-12

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Amount of lease payment to be received by lessor for operating lease in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lease payment to be received by lessor for operating lease in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479041/842-20-45-1

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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