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Employee Benefits - Narrative (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | May 07, 2014
Other retirement plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Non-current other liabilities (note 16) | $ 11,600,000 | $ 8,000,000 |  |
ICON Development Solutions Limited pension plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Expected rate of return on plan assets | 3.80% | 3.80% |  |
Aptiv Solutions pension plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Discount rate | 2.30% | 0.40% |  |
PRA Switzerland AG pension plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Discount rate | 2.30% | 0.40% |  |
United States |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Participant's contributions percentage of annual compensation (in percent) | 4.50% |  |  |
Defined contribution plan, cost | $ 30,200,000 | $ 23,700,000 | $ 17,000,000 |
United Kingdom | ICON Development Solutions Limited pension plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Non-current other liabilities (note 16) | 19,558,000 | $ 41,813,000 | $ 43,988,000 |
Net loss that will be amortized | 300,000 |  |  |
Net prior service cost for defined benefit pension plan that will be amortized | $ 0 |  |  |
Pension plan period | 19 years |  |  |
Expected rate of return on plan assets | 3.80% | 3.40% | 4.00% |
Contribution to pension fund in the year ending December 31, 2021 | $ 100,000 |  |  |
Retirement period used as a basis to estimate expected cash flows | 10 years |  |  |
Discount rate | 4.90% | 1.80% |  |
Switzerland | Aptiv Solutions pension plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Non-current other liabilities (note 16) | $ 5,806,000 | $ 7,643,000 | $ 8,620,000 |
Switzerland | Aptiv Solutions pension plan | Aptiv Solutions |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of share capital acquired (in percent) |  |  |  | 100.00%
Switzerland | PRA Switzerland AG pension plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Non-current other liabilities (note 16) | $ 5,345,000 | $ 4,990,000 | $ 4,890,000 |

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