Leases - Schedule of Operating Lease Liability Maturity (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Operating Leases
2024 (3 months remaining)	$ 9.0
2025	35.4
2026	34.9
2027	35.8
2028	36.6
Thereafter	220.4
Total operating lease payments (sublease income)	372.1
Less accreted interest	85.9
Total operating lease liabilities	$ 286.2
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities
Less current operating lease liabilities included in other current liabilities	$ 34.8
Noncurrent operating lease liabilities	251.4	$ 258.3
Sublease Income
2024 (3 months remaining)	(0.8)
2025	(3.5)
2026	(3.5)
2027	(3.5)
2028	(3.5)
Thereafter	(8.8)
Total operating lease payments (sublease income)	(23.6)
Non-cancelable future minimum lease payments under operating leases not yet commenced for 2025	5.6
Non-cancelable future minimum lease payments under operating leases not yet commenced for 2026	22.6
Non-cancelable future minimum lease payments under operating leases not yet commenced for 2027	23.3
Non-cancelable future minimum lease payments under operating leases not yet commenced for 2028	24.0
Non-cancelable future minimum lease payments under operating leases not yet commenced for thereafter	$ 214.4

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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Unrecorded Unconditional Purchase Obligation, To Be Paid, After Year Four

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

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-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.

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 440
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-Name Accounting Standards Codification
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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation 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). Includes, but is not limited to, lease not yet commenced.

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation 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). Includes, but is not limited to, lease not yet commenced.

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