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Debt - Schedule of Weighted Average Interest Rates (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Debt Instrument |  |
Interest expense | $ 13.1 | $ 6.0
Specialty Insurance Distribution (NSM) |  |
Debt Instrument |  |
Weighted Average | 277.4 | 221.0
Interest expense | $ 5.9 | $ 4.2
Weighted Average Interest rate | 8.50% | 7.60%
Specialty Insurance Distribution (NSM) | Term loan - hedged |  |
Debt Instrument |  |
Weighted Average | $ 147.6 | $ 148.4
Interest expense | $ 3.4 | $ 3.0
Weighted Average Interest rate | 9.20% | 8.10%
Specialty Insurance Distribution (NSM) | Term loan - unhedged |  |
Debt Instrument |  |
Weighted Average | $ 129.8 | $ 72.6
Interest expense | $ 2.5 | $ 1.2
Weighted Average Interest rate | 7.70% | 6.60%

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- Definition Amount of the cost of borrowed funds accounted for as interest expense for debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6036836-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 + Details
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