Employee Benefits - Change in Plan Assets (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
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		$ 34,612	$ 32,016
Expected return on plan assets		1,171	1,214	$ 574
Actual return on plan assets		2,347	2,092
Employer contributions		91	109
Plan participants' contributions		23	22
Benefits paid		(489)	(724)
Foreign currency exchange rate changes		(386)	1,097
Fair value of plan assets at end of year	$ 36,198	36,198	34,612	32,016
United Kingdom \| 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	2,849
Actual return on plan assets	15
Employer contributions	135
Plan participants' contributions	135
Benefits paid	(113)
Foreign currency exchange rate changes	(4)
Fair value of plan assets at end of year	3,017	3,017
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		7,601	6,014
Expected return on plan assets		15	21
Actual return on plan assets		(238)	519
Scheme contributions		128	105
Plan participants' contributions		95	81
Transferred balances		76	245
Settlement		(483)	0
Foreign currency exchange rate changes		(230)	616
Fair value of plan assets at end of year	6,964	6,964	$ 7,601	$ 6,014
Switzerland \| PRA Switzerland AG pension plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at end of year	$ 3,017	$ 3,017

Defined Benefit Plan, Scheme Contributions

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- Definition

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

Amount of increase (decrease) in plan assets of defined benefit plan from assets transferred into (from) plan.

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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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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 contributions received by defined benefit plan from participant which increases plan assets.

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

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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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