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Leases - Schedule of Lease Assets and Lease Liabilities (Details) - USD ($) $ in Millions | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Leases [Abstract] |  |
Operating lease assets | $ 45.2 | $ 26.5
Finance lease assets | $ 8.6 | $ 8.1
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List] | us-gaap:OtherAssets | us-gaap:OtherAssets
Total lease assets | $ 53.8 | $ 34.6
Operating lease liabilities, current | $ 8.4 | $ 4.4
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List] | us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent | us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent
Finance lease liabilities, current | $ 2.1 | $ 1.9
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List] | us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent | us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent
Operating lease liabilities, noncurrent | $ 40.2 | $ 25.6
Finance lease liabilities, noncurrent | $ 6.5 | $ 6.2
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List] | Long-term liabilities | Long-term liabilities
Total lease liabilities | $ 57.2 | $ 38.1

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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
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- Definition Amount, after accumulated amortization, of right-of-use asset from finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
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