Employee benefit plans - Net annual benefit cost (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
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| Employee benefit plans | |||
| Expected contribution to pension plans | $ 0.4 | ||
| Net annual periodic pension cost | |||
| Service cost benefits earned | 0.3 | $ 0.3 | $ 0.5 |
| Interest cost on benefit obligation | 0.5 | 0.5 | 0.6 |
| Expected return on plan assets | (0.7) | (0.7) | (0.9) |
| Settlements | 0.3 | ||
| Net period benefit cost | $ 0.4 | $ 0.1 | $ 0.2 |
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- References No definition available.
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- Definition Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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