Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share, Basic and Diluted [Abstract]
Net income	$ 28,756	$ 27,996
Net income (loss) attributable to noncontrolling interests	21	(6)
Net income attributable to The GEO Group, Inc.	$ 28,777	$ 27,990
Basic earnings per share attributable to The GEO Group, Inc.:
Weighted average shares outstanding	73,549,000	71,449,000
Per share amount	$ 0.39	$ 0.39
Diluted earnings per share attributable to The GEO Group, Inc.:
Weighted average shares outstanding	73,549,000	71,449,000
Dilutive effect of equity incentive plans	335,000	446,000
Weighted average shares assuming dilution	73,884,000	71,895,000
Income from continuing operations (in dollars per share)	$ 0.39	$ 0.39
Restricted Stock
Basic and diluted earnings per share (Textual) [Abstract]
Antidilutive securities excluded from computation of earnings per share	0	0
Stock Options
Basic and diluted earnings per share (Textual) [Abstract]
Antidilutive securities excluded from computation of earnings per share	83,790	17,070

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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Amount of income (loss) from continuing operations attributable to the noncontrolling interest. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest.

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The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) derived from continuing operations during the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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