Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Debt, Weighted Average Interest Rate Excluding Amortization Of Debt Issuance Costs

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Debt - Summary of Debt Outstanding (Details) € in Millions, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Mar. 31, 2022 EUR (€)
Debt Instrument
Total debt	$ 690.9	$ 693.0
Weighted average interest rate	6.10%	6.50%
Ark Subordinated Debt
Debt Instrument
Unamortized issuance cost	$ (5.1)	$ (5.3)
Ark 2007 Subordinated Notes, carrying value \| Ark Subordinated Debt
Debt Instrument
Amount borrowed	30.0	30.0
Ark 2021 Notes Tranche 1
Debt Instrument
Amount borrowed \| €			€ 39.1
Ark 2021 Notes Tranche 1 \| Ark Subordinated Debt
Debt Instrument
Amount borrowed	42.9	44.2
Ark 2021 Notes Tranche 2 \| Ark Subordinated Debt
Debt Instrument
Amount borrowed	47.0	47.0
Ark 2021 Notes Tranche 3 \| Ark Subordinated Debt
Debt Instrument
Amount borrowed	70.0	70.0
Ark 2021 Notes \| Ark Subordinated Debt
Debt Instrument
Total debt	$ 154.8	$ 155.9
Ark
Debt Instrument
Effective percentage	6.60%	6.90%	6.60%
Ark \| Ark Subordinated Debt
Debt Instrument
Total debt	$ 184.8	$ 185.9
NSM Bank Facility
Debt Instrument
Effective percentage	2.90%	8.20%	2.90%
Other NSM debt
Debt Instrument
Total debt	$ 0.6	$ 0.9
Kudu Credit Facility
Debt Instrument
Total debt	218.2	218.2
Other
Debt Instrument
Total debt	17.3
Term Loan \| NSM Bank Facility
Debt Instrument
Amount borrowed	275.9	277.6
Unamortized issuance cost	(5.9)	(6.4)
Total debt	$ 270.0	$ 271.2
Effective percentage	7.00%	7.30%	7.00%
Term Loan \| Other NSM debt
Debt Instrument
Effective percentage	5.80%	2.90%	5.80%
Term Loan \| Kudu Credit Facility
Debt Instrument
Amount borrowed	$ 225.4	$ 225.4
Unamortized issuance cost	$ (7.2)	$ (7.2)
Effective percentage	5.00%	4.30%	5.00%
Term Loan \| Other Operations
Debt Instrument
Amount borrowed	$ 17.8	$ 17.1
Unamortized issuance cost	$ (0.5)	$ (0.3)
Effective percentage	7.30%	7.50%	7.30%
Term Loan \| Other
Debt Instrument
Total debt		$ 16.8