Selected Quarterly Financial Data (Unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Company's quarterly financial data
Revenues	$ 427,740	$ 457,900	$ 412,843	$ 393,137	$ 383,548	$ 379,842	$ 381,653	$ 377,031	$ 1,691,620	$ 1,522,074	$ 1,479,062
Operating Income	61,954	63,318	60,889	48,570	48,009	44,829	51,387	41,259	234,731	185,484	184,353
Income from continuing operations	37,981	38,965	38,898	27,996	27,631	32,174	34,219	23,438	143,840	117,462	144,558
income (loss) from discontinued operation, net of tax					0	(2,265)	0	0	0	(2,265)	(10,660)
Net Income	37,981	38,965	38,898	27,996	27,631	29,909	34,219	23,438	143,840	115,197	133,898
Net income attributable to The GEO Group, Inc.	$ 38,051	$ 38,991	$ 38,898	$ 27,990	$ 27,611	$ 29,897	$ 34,207	$ 23,420	$ 143,930	$ 115,135	$ 134,750
Basic earnings per share
Income from continuing operations (in dollars per share)	$ 0.52	$ 0.54	$ 0.54	$ 0.39	$ 0.39	$ 0.45	$ 0.48	$ 0.33	$ 1.99	$ 1.65	$ 2.39	[1]
Income (loss) from discontinued operations					$ 0.00	$ (0.03)	$ 0.00	$ 0.00	$ 0.00	$ (0.03)	$ (0.17)	[1]
Net income per share (in dollars per share)	$ 0.52	$ 0.54	$ 0.54	$ 0.39	$ 0.39	$ 0.42	$ 0.48	$ 0.33	$ 1.99	$ 1.62	$ 2.21	[1]
Diluted earnings per share
Income from continuing operations	$ 0.52	$ 0.54	$ 0.54	$ 0.39	$ 0.38	$ 0.45	$ 0.48	$ 0.33	$ 1.98	$ 1.64	$ 2.37	[1]
Income (loss) from discontinued operations					$ 0.00	$ (0.03)	$ 0.00	$ 0.00	$ 0.00	$ (0.03)	$ (0.17)	[1]
Net income per share	$ 0.52	$ 0.54	$ 0.54	$ 0.39	$ 0.38	$ 0.42	$ 0.48	$ 0.33	$ 1.98	$ 1.61	$ 2.20	[1]

[1] Note that earnings per share tables may contain summation differences due to rounding.