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Fair Value of Financial Instruments (Details) - USD ($) $ in Millions | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | $ 690.9 | $ 693.0
Other NSM debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 0.6 | 0.9
Kudu Credit Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 218.2 | 218.2
Other Operations debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 17.3 |
Fair Value | Ark 2007 Notes |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Fair Value | 27.8 | 27.6
Fair Value | Ark 2021 Notes |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Fair Value | 163.4 | 162.8
Fair Value | NSM Bank Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Fair Value | 273.1 | 275.8
Fair Value | Other NSM debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Fair Value | 0.7 | 1.0
Fair Value | Kudu Credit Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Fair Value | 241.8 | 246.8
Fair Value | Other Operations debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Fair Value | 17.7 | 17.7
Carrying Value | Ark 2007 Notes |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 30.0 | 30.0
Carrying Value | Ark 2021 Notes |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 154.8 | 155.9
Carrying Value | NSM Bank Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 270.0 | 271.2
Carrying Value | Other NSM debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 0.6 | 0.9
Carrying Value | Kudu Credit Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 218.2 | 218.2
Carrying Value | Other Operations debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | $ 17.3 | $ 16.8

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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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