Commitments and contingencies - Narrative (Details) $ in Millions  | 
 Dec. 31, 2021  
USD ($)  
disallowance 
 | 
|---|---|
| Loss Contingencies [Line Items] | |
| Number of disallowances | disallowance | 2 | 
| Settled Litigation | |
| Loss Contingencies [Line Items] | |
| Disallowance | $ 7.3 | 
| Pending Litigation | |
| Loss Contingencies [Line Items] | |
| Disallowance | $ 19.9 | 
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- Definition Loss Contingency, Disallowed Amount No definition available. 
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- Definition Loss Contingency, Number Of Disallowances No definition available. 
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- Definition 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. No definition available. 
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- Details 
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