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v3.20.1

Subsequent Events (Details) | Mar. 09, 2020 $ / shares | Dec. 31, 2019 $ / shares | Dec. 31, 2018 $ / shares
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Subsequent Events [Line Items] |  |  |
Ordinary shares, nominal value (in dollars per share) |  | $ 0.01 | $ 0.01
Subsequent Event | Class A Ordinary Shares, $0.01 nominal value [Member] | Willis Towers Watson Public Limited Company [Member] |  |  |
Subsequent Events [Line Items] |  |  |
Stock conversion ratio | 1.08 |  |
Ordinary shares, nominal value (in dollars per share) | $ 0.01 |  |

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