Debt Outstanding (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Term loan	$ 294,750geo_TermLoans	$ 295,500geo_TermLoans
Revolver	403,000us-gaap_LineOfCredit	70,000us-gaap_LineOfCredit
Total Senior Credit Facility	697,750geo_SeniorCreditFacility	365,500geo_SeniorCreditFacility
Capital Lease Obligations	10,665us-gaap_CapitalLeaseObligations	10,924us-gaap_CapitalLeaseObligations
Other debt	667us-gaap_OtherLongTermDebt	421us-gaap_OtherLongTermDebt
Total debt	1,979,549	1,621,395
Current portion of capital lease obligations, long-term debt and non-recourse debt	(16,648)	(16,752)
Capital Lease Obligations, long-term portion	(9,574)	(9,856)
Non-Recourse Debt, long-term portion	(158,060)geo_NoncurrentPortionOfNonRecourseDebt	(131,968)geo_NoncurrentPortionOfNonRecourseDebt
Long-Term Debt	1,795,267us-gaap_LongTermDebtNoncurrent	1,462,819us-gaap_LongTermDebtNoncurrent
Non-Recourse Debt
Debt Instrument [Line Items]
Non-Recourse Debt	171,138	145,262
Unamortized discount on non-recourse debt	(671)	(712)
Total Non-Recourse Debt	170,467	144,550
5.875% Senior Notes, Due 2024 \| Senior Notes
Debt Instrument [Line Items]
Senior Notes	250,000	250,000
Interest rate	5.875%	5.875%
5.125% Senior Notes, Due 2023 \| Senior Notes
Debt Instrument [Line Items]
Senior Notes	300,000	300,000
Interest rate	5.125%	5.125%
5.875% Senior Notes, Due 2022 \| Senior Notes
Debt Instrument [Line Items]
Senior Notes	250,000	250,000
Interest rate	5.875%	5.875%
6.625% Senior Notes, Due 2021 \| Senior Notes
Debt Instrument [Line Items]
Senior Notes	$ 300,000	$ 300,000
Interest rate	6.625%	6.625%

Long term debt, nonrecourse debt and capital lease obligation including current portion, net of discount.

No definition available.

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- Definition

Noncurrent portion of non-recourse debt .

+ References

No definition available.

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- Definition

Non-recourse debt, excluding premium discount.

+ References

No definition available.

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- Definition

Total senior credit facility.

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No definition available.

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- Definition

Term loans.

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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- Definition

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

+ References

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Amount of debt for which creditor does not have general recourse to the debtor but rather has recourse only to the property used for collateral in the transaction or other specific property.

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No definition available.

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- Definition

Including both current and noncurrent portions, carrying amount as of the balance sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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