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Segment Information - Narrative (Details) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2022 USD ($) segment | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Revenue from External Customer [Line Items] |  |  |
Number of reportable segment | segment | 1 |  |
Other long-lived assets | $ 3,702.5 | $ 3,791.8 | $ 3,844.8
Solothurn, Switzerland |  |  |
Revenue from External Customer [Line Items] |  |  |
Other long-lived assets | $ 2,198.5 | $ 2,237.0 | $ 2,180.6

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- Definition Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 41 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9038-108599 + Details
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