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Employee Benefits - Plan Asset Fair Value Measurements (Details) - ICON Development Solutions Limited pension plan - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
High yield percentage of corporate bond investment	50.00%
Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 36,198	$ 34,612
Fair Value, Inputs, Level 1 | Cash
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	162	11
Fair Value, Inputs, Level 1 | L&G Life GPBF All World Equity Index Fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8,743	7,460
Fair Value, Inputs, Level 1 | L&G Life DC Active Corporate Bond
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6,409	6,797
Fair Value, Inputs, Level 1 | Stone Harbor High Yield Bond Fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6,965	6,861
Fair Value, Inputs, Level 1 | Ninety One Global Total Return Credit
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,435	3,472
Fair Value, Inputs, Level 1 | Stone Harbor Multi Asset Credit Portfolio
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,359	3,389
Fair Value, Inputs, Level 1 | Barings European Loan Fund Buy & Hold
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 7,125	$ 6,622

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Defined Benefit Plan, Plan Assets, Corporate Bonds Target Allocation, High Yield Percentage

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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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