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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- Definition

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

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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.

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No definition available.

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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.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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- Definition

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

+ References

No definition available.

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Debt - Summary of Debt Outstanding (Details) € in Millions, $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2021 EUR (€)
Debt Instrument
Total debt	$ 710.4	$ 376.4
Weighted average interest rate	6.70%	7.00%
Ark Subordinated Debt
Debt Instrument
Unamortized issuance cost	$ (5.5)
Ark 2007 Notes Tranche 1 \| Ark Subordinated Debt
Debt Instrument
Amount borrowed	30.0
Ark 2007 Notes Tranche 2 \| Ark Subordinated Debt
Debt Instrument
Amount borrowed	13.9
Ark 2007 Notes \| Ark Subordinated Debt
Debt Instrument
Total debt	43.9
Ark 2021 Notes Tranche 1
Debt Instrument
Amount borrowed \| €			€ 39.1
Ark 2021 Notes Tranche 1 \| Ark Subordinated Debt
Debt Instrument
Amount borrowed	45.3
Ark 2021 Notes Tranche 2 \| Ark Subordinated Debt
Debt Instrument
Amount borrowed	47.0
Ark 2021 Notes Tranche 3 \| Ark Subordinated Debt
Debt Instrument
Amount borrowed	70.0
Ark 2021 Notes \| Ark Subordinated Debt
Debt Instrument
Total debt	$ 156.8
Ark
Debt Instrument
Effective percentage	5.10%		5.10%
Ark \| Ark Subordinated Debt
Debt Instrument
Total debt	$ 200.7
NSM Bank Facility
Debt Instrument
Effective percentage	8.30%	8.40%	8.30%
Other NSM debt
Debt Instrument
Total debt	$ 1.3	$ 1.3
Kudu Credit Facility
Debt Instrument
Total debt	195.6
Other
Debt Instrument
Total debt	19.1
Term Loan \| NSM Bank Facility
Debt Instrument
Amount borrowed	300.4	277.4
Unamortized issuance cost	(6.7)	(6.1)
Total debt	$ 293.7	$ 271.3
Effective percentage	7.40%	7.50%	7.40%
Term Loan \| Other NSM debt
Debt Instrument
Effective percentage	3.30%	2.50%	3.30%
Term Loan \| Kudu Credit Facility
Debt Instrument
Amount borrowed	$ 203.0
Unamortized issuance cost	$ (7.4)
Effective percentage	4.10%		4.10%
Term Loan \| Kudu Bank Facility
Debt Instrument
Amount borrowed		$ 89.2
Unamortized issuance cost		(2.9)
Total debt		$ 86.3
Effective percentage		8.30%
Term Loan \| Other Operations
Debt Instrument
Amount borrowed	$ 19.5	$ 18.0
Unamortized issuance cost	$ (0.4)	$ (0.5)
Effective percentage	7.40%	7.40%	7.40%
Term Loan \| Other
Debt Instrument
Total debt		$ 17.5