Equity Incentive Plans (Details Textual) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Apr. 01, 2012
Equity Incentive Plans (Additional Textual) [Abstract]
Number of annual performance metrics	2
Share based compensation awards other than option [Member]
Equity Incentive Plans (Additional Textual) [Abstract]
Common stock available for the issuance of awards	656,804
Restricted Stock [Member]
Equity Incentive Plans (Additional Textual) [Abstract]
Share based compensation expense	$ 1.3	$ 1.0
Unrecognized compensation costs related to non vested stock option awards	7.1
Expected weighted average period to recognize expense	2 years 1 month 6 days
Restricted Stock [Member] \| Minimum
Equity Incentive Plans (Additional Textual) [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Restricted Stock [Member] \| Maximum
Equity Incentive Plans (Additional Textual) [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Weighted Towards Earnings Per Share Performance	75.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Weighted Towards Capital Performance Targets	25.00%
Employee Stock Purchase Plan [Member]
Equity Incentive Plans (Additional Textual) [Abstract]
Discount on purchase of Common Stock for employee from the current market price	5.00%
Maximum Shares Authorized Under ESPP for Sale Offer to Eligible Employees	500,000
Stock Issued During Period, Shares, Employee Stock Purchase Plans	2,004
Stock Options [Member]
Equity Incentive Plans (Additional Textual) [Abstract]
Share based compensation expense	0.4	0.5
Unrecognized compensation costs related to non vested stock option awards	$ 2.2
Expected weighted average period to recognize expense	2 years
Stock Incentive Plan [Member]
Equity Incentive Plans (Additional Textual) [Abstract]
Common stock available for the issuance of awards	1,292,787

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Maximum shares authorized under ESPP for sale offer to eligible employees

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- Definition

Number of annual performance metrics for the performance-based equity grants under GEO's equity incentive plans.

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Weighted Towards Capital Performance Targets

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Weighted Towards Earnings Per Share Performance

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The discount rate from market value on purchase date that participants pay for shares.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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-Name Accounting Standards Codification

-Topic 505

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

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-Name Regulation S-X (SX)

-Number 210

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-Paragraph 29, 30

-Article 5

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