Employee Benefits - Change in Plan Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
United Kingdom \| ICON Development Solutions Limited pension plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	$ 26,050	$ 36,198
Expected return on plan assets	1,015	1,258	$ 1,171
Actuarial loss	(910)	(7,305)
Employer contributions	70	70
Plan participants' contributions	19	19
Benefits paid	(318)	(514)
Foreign currency exchange rate changes	1,394	(3,676)
Fair value of plan assets at end of year	27,320	26,050	36,198
Switzerland \| Aptiv Solutions pension plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	5,681	6,964
Expected return on plan assets	133	29
Actuarial loss	356	(987)
Scheme contributions	215	114
Plan participants' contributions	93	82
Benefits paid and transferred balances	134	182
Settlement	(645)	(218)
Foreign currency exchange rate changes	562	(121)
Fair value of plan assets at end of year	6,261	5,681	6,964
Switzerland \| PRA Switzerland AG pension plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	4,059	3,017
Expected return on plan assets	101	29
Actuarial loss	(52)	87
Scheme contributions	456	325
Plan participants' contributions	456	325
Benefits paid and transferred balances	795	1,125
Settlement	(753)	(844)
Foreign currency exchange rate changes	467	(5)
Fair value of plan assets at end of year	$ 5,529	$ 4,059	$ 3,017

Defined Benefit Plan, Plan Assets, Benefits Paid And Increase (Decrease) For Balance Transfers

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- Definition

Defined Benefit Plan, Scheme Contributions

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Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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- Definition

Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

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- Definition

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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- Definition

Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

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- Definition

Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

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