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Maximum shares authorized under ESPP for sale offer to eligible employees

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

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

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

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Share based compensation arrangement by share based payment award options granted in period total fair value.

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Share Based Compensation Arrangement by Share Based Payment Award Other Than Options Granted in Period Fair Value

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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.

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

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

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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

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Number of shares that have been repurchased and retired during the period.

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Equity Incentive Plans (Details Textual) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended		9 Months Ended		9 Months Ended		12 Months Ended	9 Months Ended			9 Months Ended
	Sep. 30, 2012	Jul. 20, 2012 performance_metrics	Sep. 30, 2012 Senior Employee and Director [Member]	Sep. 30, 2012 Share based compensation awards other than option [Member]	Sep. 30, 2012 Restricted Stock [Member]	Oct. 02, 2011 Restricted Stock [Member]	Jan. 01, 2012 Restricted Stock [Member]	Sep. 30, 2012 Restricted Stock [Member] Minimum [Member]	Sep. 30, 2012 Restricted Stock [Member] Maximum [Member]	Jul. 20, 2012 Restricted Stock [Member] Maximum [Member]	Sep. 30, 2012 Employee Stock Purchase Plan [Member]	Sep. 30, 2012 Stock Options [Member]	Oct. 02, 2011 Stock Options [Member]	Sep. 30, 2012 Performance Based Share [Member]	Sep. 30, 2012 Stock Incentive Plan [Member]
Equity Incentive Plans (Additional Textual) [Abstract]
Common stock available for the issuance of awards				651,804											1,396,954
Retirement of common stock, shares	57,457
Share-based compensation arrangement by share based payment award options granted aggregate fair value	$ 0.7
Share based compensation expense					3.2	2.6						1.9	2.2
Unrecognized compensation costs related to non vested stock option awards					9.6							3.2
Expected weighted average period to recognize expense					2 years 6 months							2 years 4 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years							3 years	4 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	315,000		315,000											205,000
Number of annual performance metrics		2
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%
Grant Date Fair Value of Equity Awards Issued During Period					$ 5.8		$ 9.3
Discount on purchase of Common Stock for employee from the current market price											5.00%
Stock Issued During Period, Shares, Employee Stock Purchase Plans	19,487
Maximum Shares Authorized Under ESPP for Sale Offer to Eligible Employees											500,000