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Employee Benefits - Funded Status (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | --- | ---
United Kingdom | ICON Development Solutions Limited pension plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Projected benefit obligation | $ (19,558) | $ (41,813) |
Fair value of plan assets | 26,050 | 36,198 | $ 34,612
Funded status | 6,492 | (5,615) |
Switzerland | Aptiv Solutions pension plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Projected benefit obligation | (5,806) | (7,643) |
Fair value of plan assets | 5,681 | 6,964 | 7,601
Funded status | (125) | (679) |
Switzerland | PRA Switzerland AG pension plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Projected benefit obligation | (5,345) | (4,990) |
Fair value of plan assets | 4,059 | 3,017 | $ 2,849
Funded status | $ (1,286) | $ (1,973) |

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