Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Plan Period

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- Definition

Expected Retirement period

+ References

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

+ References

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- Definition

Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

+ References

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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- Definition

Amount of cost for defined contribution plan.

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

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Employee Benefits - Narrative (Details) - USD ($)	12 Months Ended
Employee Benefits - Narrative (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	May 07, 2014
Other retirement plans
Defined Benefit Plan Disclosure [Line Items]
Non-current other liabilities (note 16)	$ 12,300,000	$ 11,600,000
ICON Development Solutions Limited pension plan
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	3.80%	3.80%
PRA Switzerland AG pension plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate	1.50%	2.30%
United States
Defined Benefit Plan Disclosure [Line Items]
Participant's contributions percentage of annual compensation (in percent)	4.50%
Defined contribution plan, cost	$ 40,400,000	$ 45,800,000	$ 23,700,000
United Kingdom \| ICON Development Solutions Limited pension plan
Defined Benefit Plan Disclosure [Line Items]
Non-current other liabilities (note 16)	20,999,000	$ 19,558,000	$ 41,813,000
Net loss that will be amortized	200,000
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%	3.80%	3.40%
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	4.80%	4.90%
Switzerland \| Aptiv Solutions pension plan
Defined Benefit Plan Disclosure [Line Items]
Non-current other liabilities (note 16)	$ 6,441,000	$ 5,806,000	$ 7,643,000
Discount rate	1.50%	2.30%
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)	$ 7,747,000	$ 5,345,000	$ 4,990,000