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Employee Benefits - Funded Status (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
United Kingdom | ICON Development Solutions Limited pension plan
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ (20,999)	$ (19,558)
Fair value of plan assets	27,320	26,050	$ 36,198
Funded surplus	6,321	6,492
Switzerland | Aptiv Solutions pension plan
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	(6,441)	(5,806)
Fair value of plan assets	6,261	5,681	6,964
Funded surplus	(180)	(125)
Switzerland | PRA Switzerland AG pension plan
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	(7,747)	(5,345)
Fair value of plan assets	5,529	4,059	$ 3,017
Funded surplus	$ (2,218)	$ (1,286)

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

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