XML 132 R118.htm IDEA: XBRL DOCUMENT v3.22.4

Employee Benefit Plans - Schedule of amounts contributed to defined contribution plans in various jurisdictions (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	$ 132,228	$ 119,382	$ 96,447
India
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	43,805	37,508	30,396
Foreign Plan | U.S.
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	23,084	21,496	19,491
Foreign Plan | U.K.
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	20,763	19,874	18,643
Foreign Plan | China
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	26,514	24,988	16,436
Foreign Plan | Other regions
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plans, contributed amount	$ 18,062	$ 15,516	$ 11,481

X

- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

Name:	us-gaap_DefinedContributionPlanCostRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- 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.

+ Details

Name:	us-gaap_DefinedContributionPlanDisclosureLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_RetirementPlanSponsorLocationAxis=country_IN
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RetirementPlanSponsorLocationAxis=us-gaap_ForeignPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	g_LocationOfForeignPlanAxis=country_US
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	g_LocationOfForeignPlanAxis=country_GB
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	g_LocationOfForeignPlanAxis=country_CN
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	g_LocationOfForeignPlanAxis=g_OtherRegionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: