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Fair Value of Financial Instruments (Details) - USD ($) $ in Millions | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying value | $ 429.7 | $ 376.4
Other NSM debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying value |  | 1.3
Fair Value | Ark Subordinated Debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Debt, fair value | 44.1 | 0.0
Fair Value | NSM Bank Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Debt, fair value | 275.6 | 279.3
Fair Value | Other NSM debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Debt, fair value | 1.3 | 1.3
Fair Value | Kudu Credit Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Debt, fair value | 102.0 | 0.0
Fair Value | Kudu Bank Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Debt, fair value | 0.0 | 89.3
Fair Value | Other Operations debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Debt, fair value | 18.3 | 18.8
Carrying Value | Ark Subordinated Debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying value | 44.1 | 0.0
Carrying Value | NSM Bank Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying value | 271.5 | 271.3
Carrying Value | Other NSM debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying value | 1.2 | 1.3
Carrying Value | Kudu Credit Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying value | 95.9 | 0.0
Carrying Value | Kudu Bank Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying value | 0.0 | 86.3
Carrying Value | Other Operations debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying value | $ 17.0 | $ 17.5

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- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611 + Details
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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 Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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