XML 54 R38.htm IDEA: XBRL DOCUMENT
v3.22.0.1

Significant accounting policies (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2021
Accounting Policies [Abstract] |
Adjustments Resulting From Foreign Currency Translations | Amounts charged or credited to the Consolidated Statements of Operations for the years ended December 31, 2021, December 31, 2020 and December 31, 2019 were as follows:
| Year ended December 31,
| 2021 | 2020 | 2019
| (in thousands)
Amounts (credited)/charged | $ | (14,316) |  | $ | 5,979 |  | $ | 590 |
Estimated Useful Lives of Assets | Depreciation of property, plant and equipment is computed using the straight line method based on the estimated useful lives of the assets as listed below:
| Years
Building | 40
Computer equipment and software | 2-8
Office furniture and fixtures | 8
Laboratory equipment | 5
Motor vehicles | 5

X
- Definition Foreign Currency Disclosure + References No definition available. + Details
Name: | iclr_ForeignCurrencyDisclosureTableTextBlock
Namespace Prefix: | iclr_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule Of Useful Lives For Property Plant Equipment + References No definition available. + Details
Name: | iclr_ScheduleOfUsefulLivesForPropertyPlantEquipmentTextBlock
Namespace Prefix: | iclr_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_AccountingPoliciesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration