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

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- Definition

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

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- Definition

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

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Vesting Percentage of Target

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- Definition

Stock option vest immediately for the Chief Executive Officer.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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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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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

Discount rate from fair value on purchase date that participants pay for shares.

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-Publisher FASB
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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
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Equity Incentive Plans (Details Textual) $ in Millions	3 Months Ended	12 Months Ended
Equity Incentive Plans (Details Textual) $ in Millions	Dec. 31, 2017 USD ($) metrics shares	Dec. 31, 2017 USD ($) metrics shares	Dec. 31, 2016 shares	Dec. 31, 2015 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding, number outstanding (in shares)	1,230,000	1,230,000
Vesting period		4 years
Stock option vest immediately for the chief executive officer		100.00%
Expiration period		10 years
Restricted Stock Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested awards other than options	1,770,000	1,770,000	1,345,000
Unrecognized compensation costs related to awards \| $	$ 33.4	$ 33.4
Expected weighted average period to recognize expense		2 years 6 months
Granted shares		933,000
Restricted Stock Award \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Restricted Stock Award \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Restricted Stock Award \| Certain Employees and Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted shares		933,000	524,000	635,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to awards \| $	$ 2.0	$ 2.0
Expected weighted average period to recognize expense		2 years 10 months 24 days
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Number of annual performance metrics \| metrics	2	2
Vesting rights, percentage weighted towards EPS performance	50.00%	50.00%	50.00%
Vesting rights, percentage weighted towards capital performance	50.00%	50.00%	50.00%
Performance Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of target		0.00%
Performance Shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of target		200.00%
Performance Shares \| Certain Employees and Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted shares		352,500	173,000	223,000
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount on purchase of Common Stock for employee from the current market price		5.00%
Capital shares reserved for future issuance	750,000	750,000
Shares issued for ESPP	20,009		23,037	19,808
2014 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized				4,625,030
Common stock available for the issuance of awards	3,000,000	3,000,000
2006 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for the issuance of awards	1,625,030	1,625,030