Commitments and contingencies - Guarantees and Contingencies (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|
Dec. 31, 2019 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2019 |
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| Contingencies | |||||
| Impairment | $ 5.8 | $ 101.1 | |||
| Insurance receivable | $ 13.5 | 13.5 | |||
| Insurance | 1.0 | ||||
| Capital expenditures | 7.3 | $ 1.8 | $ 5.5 | ||
| Insurance proceeds | $ 11.3 | ||||
| Cadillac Project | |||||
| Contingencies | |||||
| Business interruption loss period | 45 days | ||||
| Business interruption expected revenue loss | $ 1.4 | ||||
| Impairment | 25.0 | ||||
| Write-down of capital spares | 0.6 | 0.3 | |||
| Insurance receivable | $ 24.2 | ||||
| Insurance | 1.0 | ||||
| Capital expenditures | 5.1 | ||||
| Insurance Recoveries | 11.3 | 11.3 | |||
| Insurance Settlements Receivable | 13.5 | $ 13.5 | $ 24.2 | ||
| Gain on business interruption insurance recovery | $ 2.0 | ||||
| X | ||||||||||
- Definition The amount of expected business interruption loss of revenue. No definition available.
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| X | ||||||||||
- Definition The period of days business interruption loss covered. No definition available.
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition The net amount (to the extent disclosed within this portion of the income statement) by which an insurance settlement exceeds incremental costs incurred from the event causing an interruption of business, plus the insurance award for earnings lost from the event, such as a natural catastrophe, explosion or fire. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy. No definition available.
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| X | ||||||||||
- Definition Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount of excess (deficiency) of insurance recovery over the loss incurred from an insured event. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- 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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- Definition Amount of cash inflow for proceeds from settlement of insurance claim, classified as investing activities. Excludes insurance settlement classified as operating activities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. No definition available.
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- Details
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