Employee benefit plans - Amounts recognized and significant components (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
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| Amount recognized in the balance sheet | |||
| Non-current liabilities | $ 1.2 | $ 1.2 | |
| Amounts recognized in accumulated OCL | |||
| Unrecognized loss | (1.7) | 1.4 | |
| Amortization of net loss for the pension plan from accumulated OCI to net periodic cost over the next fiscal year | 0.0 | ||
| Balances of significant components of the pension plan | |||
| Projected benefit obligation | 14.1 | 13.2 | $ 15.8 |
| Accumulated benefit obligation | 12.9 | 12.2 | |
| Fair value of plan assets | 12.9 | 12.0 | $ 13.9 |
| Amount invested in common collective trust | 12.9 | $ 12.0 | |
| Amount of investments categorized as Level 1 or Level 3 | $ 0.0 | ||
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- References No definition available.
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- Definition The amount of plan assets invested in a common collective trust. No definition available.
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- Definition The amount of investments in common collective trust that are categorized as Level 1 or Level 3. No definition available.
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- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as noncurrent. Excludes other postretirement benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount, after tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cost (credit) included in accumulated other comprehensive (income) loss expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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