Additional Interest

No definition available.

Name:	geo_AdditionalInterest
Namespace Prefix:	geo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Notice Period Prior to Redemption

+ References

No definition available.

+ Details

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

- Definition

Debt Instrument, Redemption Period, Percentage of Principal Amount Redeemable

+ References

No definition available.

+ Details

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

- Definition

Debt Instrument, Redemption Price Calculation Contributor, Percentage

+ References

No definition available.

+ Details

Name:	geo_DebtInstrumentRedemptionPriceCalculationContributorPercentage
Namespace Prefix:	geo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer. [2013 New Element]

+ References

No definition available.

+ Details

Name:	geo_DebtInstrumentRedemptionPricePercentage
Namespace Prefix:	geo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Redemption Price, Percentage of Principal Remaining After Redemption

+ References

No definition available.

+ Details

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

- Definition

Declare Period After Closing of Offering

+ References

No definition available.

+ Details

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

- Definition

File Period After Closing of Offering

+ References

No definition available.

+ Details

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

- Definition

Redemption Period

+ References

No definition available.

+ Details

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

- Definition

Redemption Period After Closing of Offering

+ References

No definition available.

+ Details

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

- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

- Definition

Interest rate stated in the contractual debt agreement.

+ References

+ Details

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

- Details

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

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

Debt Senior Notes (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended	6 Months Ended
	Mar. 19, 2013	Jun. 30, 2013
Debt Instrument [Line Items]
Interest rate		7.75%
Senior Notes Due 2013 \| Senior Notes
Debt Instrument [Line Items]
Interest rate		7.75%
Senior Unsecured Notes Due April 2023
Debt Instrument [Line Items]
Redemption Period After Closing of Offering		0 years 0 months 90 days
Senior Unsecured Notes Due April 2023 \| Senior Notes
Debt Instrument [Line Items]
Face amount	$ 300,000
Debt Instrument, Maturity Date	Apr. 01, 2023
Interest rate	5.125%	5.125%
Debt Instrument, Redemption Price Calculation Contributor, Percentage	100.00%
Debt Instrument, Redemption Price, Percentage	105.125%
Redemption period beginning April 1, 2018		12 months
Registration Rights Agreement [Member]
Debt Instrument [Line Items]
File Period After Closing of Offering	0 years 0 months 75 days
Declare Period After Closing of Offering	0 years 0 months 180 days
Registration Rights Agreement [Member] \| Senior Notes
Debt Instrument [Line Items]
Additional Interest	0.25%
Senior Notes Due 2021 \| Senior Notes
Debt Instrument [Line Items]
Interest rate		6.625%
Maximum \| Senior Unsecured Notes Due April 2023
Debt Instrument [Line Items]
Notice Period Prior to Redemption		0 years 0 months 60 days
Maximum \| Senior Unsecured Notes Due April 2023 \| Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Redemption Period, Percentage of Principal Amount Redeemable	35.00%
Maximum \| Registration Rights Agreement [Member]
Debt Instrument [Line Items]
Additional Interest	1.00%
Minimum \| Senior Unsecured Notes Due April 2023
Debt Instrument [Line Items]
Notice Period Prior to Redemption		0 years 0 months 30 days
Minimum \| Senior Unsecured Notes Due April 2023 \| Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Remaining After Redemption	65.00%