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Income taxes: - Loss carry-forwards (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2025 USD ($)
Income taxes |
Net operating loss carry-forwards | $ 1,200.0
UNITED STATES |
Income taxes |
Net operating loss carry-forwards | 131.7
Europe |
Income taxes |
Net operating loss carry-forwards | 1,000.0
Carry-forwards not limited for use | 883.6
Carry-forwards limited for use | 156.7
Other than Europe |
Income taxes |
Net operating loss carry-forwards | $ 32.7

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- Definition Amount of operating loss carryforwards not available for use in the future. + References No definition available. + Details
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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-3 + Details
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