Shareholders' Equity - Changes in Shareholders' Equity (Parenthetical) (Details) - USD ($)	Feb. 26, 2020	Jul. 01, 2021
George C. Zoley \| Amended and Restated Executive Retirement Agreement
Class of Stock [Line Items]
Deferred compensation arrangement with individual, cash payment		$ 3,600,000
Deferred compensation arrangement with individual reclassification from equity to other non-current liabilities		$ 3,600,000
Common shares
Class of Stock [Line Items]
Deferred compensation arrangement with individual, value of shares issued	$ 8,925,065
Deferred compensation arrangement with individual, shares issued	553,665

Deferred compensation arrangement with individual reclassification from equity to other non-current liabilities.

No definition available.

Name:	geo_DeferredCompensationArrangementWithIndividualReclassificationFromEquityToOtherNonCurrentLiabilities
Namespace Prefix:	geo_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

- Definition

Amount of commitment made to pay deferred cash remuneration.

+ References

No definition available.

+ Details

Name:	us-gaap_DeferredCompensationArrangementWithIndividualCashAwardGrantedAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The total fair value of shares issued during the period under a deferred compensation arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

Name:	us-gaap_DeferredCompensationArrangementWithIndividualFairValueOfSharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of shares issued pursuant to the terms of a deferred compensation arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

Name:	us-gaap_DeferredCompensationArrangementWithIndividualSharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_TitleOfIndividualAxis=geo_GeorgeCZoleyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TypeOfArrangementAxis=geo_AmendedAndRestatedExecutiveRetirementAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: