Commitments and contingencies (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($) claim	Dec. 31, 2020 USD ($)
Loss Contingencies [Line Items]
Lease not yet commenced, amount	$ 16.2	$ 19.2
Alleged damages	25.0 million
Number of arbitrations \| claim	13
Private Equity Funds
Loss Contingencies [Line Items]
Contractual obligation	$ 4.3
Minimum
Loss Contingencies [Line Items]
Maximum estimated range of aggregate loss for legal proceedings	0.0
Maximum
Loss Contingencies [Line Items]
Maximum estimated range of aggregate loss for legal proceedings	$ 30.0

Lessee, Operating Lease, Lease Not Yet Commenced, Amount

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- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

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Describes the form and magnitude of the award the plaintiff seeks in the legal matter, which may include an unspecified amount of money.

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Number of pending claims pertaining to a loss contingency.

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The difference between the maximum amount of estimated loss and the amount recorded as of the balance sheet date.

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