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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

Weighted average interest rate of debt outstanding.

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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

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Long-Term Debt, Average Amount Outstanding

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