Letters of credit outstanding relating to performance guarantees.

No definition available.

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

- Definition

Maximum loan amount under SACS shareholder's loan.

+ References

No definition available.

+ Details

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Namespace Prefix:	geo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of letters of guarantee outstanding under separate international facilities relating to performance guarantees.

+ References

No definition available.

+ Details

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Namespace Prefix:	geo_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Potential estimated exposure of tax obligations.

+ References

No definition available.

+ Details

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

- Definition

Remaining guarantee under letter of credit.

+ References

No definition available.

+ Details

Name:	geo_RemainingGuaranteeUnderLetterOfCredit
Namespace Prefix:	geo_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Working Capital Line of Credit Issue to GEO Amey

+ References

No definition available.

+ Details

Name:	geo_WorkingCapitalLineofCreditIssuedtoGEOAmey
Namespace Prefix:	geo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership, due after 1 year (or 1 business cycle).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
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-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.11)
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-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 3
-Subparagraph a
-Article 5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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

- Definition

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13476-108611

+ Details

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Namespace Prefix:	us-gaap_
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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

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

- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=52262685&loc=SL6759159-111685

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Balance Type:	na
Period Type:	duration

- Details

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- Details

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Balance Type:
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- Details

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- Details

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- Details

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Debt - Guarantees (Details) - 3 months ended Mar. 31, 2016 £ in Millions, CAD in Millions, AUD in Millions	ZAR	AUD guarantee	CAD guarantee	ZAR guarantee	USD ($) guarantee	GBP (£) guarantee
Geo Amey
Line of Credit Facility [Line Items]
Ownership percentage in South African Custodial Services Pty. Limited	50.00%
Working capital line of credit issued to GEOAmey \| £						£ 12.0
Note receivable for GEOAmey					$ 12,200,000	£ 8.5
Ravenhall
Line of Credit Facility [Line Items]
Number of letters of guarantee outstanding under separate international facilities relating to performance guarantees \| guarantee		11	11	11	11	11
Letters of credit outstanding relating to performance guarantees					$ 16,300,000
Ravenhall \| Letter of Credit \| Revolver
Line of Credit Facility [Line Items]
Guaranteed obligations		AUD 215.0			164,900,000
SACS
Line of Credit Facility [Line Items]
Guaranteed obligations				ZAR 15,000,000	1,000,000
Remaining guarantee under letter of credit \| ZAR	ZAR 15,000,000
Maximum loan amount under standby facility				ZAR 20,000,000	1,347,200.0000
Amount funded					0
Canada Facility
Line of Credit Facility [Line Items]
Potential estimated exposure of tax obligations			CAD 1.5		$ 1,200,000