Life term of contract.

No definition available.

Name:	geo_ContractAwardTerm
Namespace Prefix:	geo_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of profit share of noncontrolling in joint venture.

+ References

No definition available.

+ Details

Name:	geo_PercentageOfProfitShareOfNoncontrollingInJointVenture
Namespace Prefix:	geo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of profit share of parent in joint venture.

+ References

No definition available.

+ Details

Name:	geo_PercentageOfProfitShareOfParentInJointVenture
Namespace Prefix:	geo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

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

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of cash outflow in the form of ordinary dividends provided by the non-wholly owned subsidiary to noncontrolling interests.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

+ Details

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

- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=geo_MunicipalCorrectionsFinanceL.P.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=geo_SouthAfricanCustodialServicesPtyLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Shareholders' Equity (Noncontrolling Interests) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Aug. 31, 2012	Aug. 30, 2012	Aug. 12, 2010
Noncontrolling Interest [Line Items]
Ownership percentage				100.00%	0.00%
Distribution to noncontrolling interests	$ 0	$ 0	$ 5,758
MCF
Noncontrolling Interest [Line Items]
Non-controlling interest, as a percentage of equity						100.00%
Ownership percentage				100.00%
Distribution to noncontrolling interests			$ 5,800
SACS
Noncontrolling Interest [Line Items]
Life term of contract	25 years
Percentage of profit share of parent in joint venture	88.75%
Percentage of profit share of noncontrolling in joint venture	11.25%