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Claims, Lawsuits And Other Contingencies (Details) - Jardine Lloyd Thompson Group plc case in Thousands, £ in Millions, $ in Millions | 48 Months Ended |  |  |
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Dec. 31, 2018 case | Jun. 30, 2021 GBP (£) | Jun. 30, 2021 USD ($) | Dec. 31, 2020 GBP (£) | Dec. 31, 2020 USD ($) | Feb. 28, 2019 GBP (£) | Feb. 28, 2019 USD ($)
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Individual cases analyzed | 14 |  |  |  |  |  |
Loss contingency accrual |  | £ 99 | $ 137 | £ 155 | $ 210 | £ 59 | $ 77

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