Interest rate swaps - Interest rate derivatives (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Interest Rate Swap Matured On 09/01/2035
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	$ 24.0
Asset (liability)	$ 0.7	$ (5.3)
Interest Rate Swap Matured On 09/01/2035 \| Minimum
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fixed interest rate	4.88%
Interest Rate Swap Matured On 09/01/2035 \| Maximum
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fixed interest rate	5.05%
Interest Rate Swap Matured On 10/01/2031
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	$ 13.0
Fixed interest rate	2.79%
Asset (liability)	$ 1.4	$ 0.3
Interest rate swap
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	100.0
Gain on derivative	$ 1.7

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Fixed interest rate related to the interest rate derivative.

+ References

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
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Nominal or face amount used to calculate payment on derivative.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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