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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
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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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