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Leases - Schedule of Right-of-Use Assets and Lease Liabilities (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Lessee, Lease, Description [Line Items] |  |
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List] | Other assets | Other assets
ROU lease asset | $ 42.2 | $ 37.6
Operating Lease, Liability, Statement of Financial Position [Extensible List] | Other liabilities | Other liabilities
Lease liability | $ 45.2 | $ 38.3
Weighted Average Incremental Borrowing Rate | 5.00% | 4.60%
HG/BAM |  |
Lessee, Lease, Description [Line Items] |  |
ROU lease asset | $ 7.6 | $ 10.1
Lease liability | 8.1 | 10.1
NSM |  |
Lessee, Lease, Description [Line Items] |  |
ROU lease asset | 14.0 | 17.1
Lease liability | 15.2 | 17.1
Kudu |  |
Lessee, Lease, Description [Line Items] |  |
ROU lease asset | 6.5 | 2.0
Lease liability | 7.1 | 2.0
Other |  |
Lessee, Lease, Description [Line Items] |  |
ROU lease asset | 7.1 | 8.4
Lease liability | 7.8 | $ 9.1
Ark |  |
Lessee, Lease, Description [Line Items] |  |
ROU lease asset | 7.0 |
Lease liability | $ 7.0 |

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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 Present value of lessee's discounted obligation for lease payments from operating 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 (b) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
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- Definition Amount of lessee's right to use underlying asset under operating 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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