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Leases - Schedule of Right-of-Use Assets and Lease Liabilities (Details) - USD ($) $ in Millions | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Lessee, Lease, Description [Line Items] |  |
ROU lease asset | $ 34.0 | $ 22.6
Lease liability | $ 34.2 | $ 22.8
Operating lease, weighted average incremental borrowing rate, percent | 4.80% | 4.60%
HG/BAM |  |
Lessee, Lease, Description [Line Items] |  |
ROU lease asset | $ 9.8 | $ 10.4
Lease liability | 9.8 | 10.4
NSM Holding Co LLC |  |
Lessee, Lease, Description [Line Items] |  |
ROU lease asset | 16.8 | 4.8
Lease liability | 16.8 | 4.8
Kudu investments |  |
Lessee, Lease, Description [Line Items] |  |
ROU lease asset | 2.2 | 2.3
Lease liability | 2.2 | 2.3
Other |  |
Lessee, Lease, Description [Line Items] |  |
ROU lease asset | 5.2 | 5.1
Lease liability | $ 5.4 | $ 5.3

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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=77888419&loc=SL77918627-209977 + Details
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