Selected Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
Company's quarterly financial data
Revenues		$ 500,127	$ 469,866	$ 445,945	$ 427,369	$ 427,740	$ 457,900	$ 412,843	$ 393,137	$ 1,843,307		$ 1,691,620		$ 1,522,074
Operating Income		66,745	63,031	53,281	52,672	61,954	63,318	60,889	48,570	235,729		234,731		185,484
Income from continuing operations						37,981	38,965	38,898	27,996	139,315		143,840		117,462
income (loss) from discontinued operation, net of tax										0		0		(2,265)
Net Income		44,015	38,291	28,253	28,756	37,981	38,965	38,898	27,996	139,315		143,840		115,197
Net income attributable to The GEO Group, Inc.		$ 44,058	$ 38,312	$ 28,291	$ 28,777	$ 38,051	$ 38,991	$ 38,898	$ 27,990	$ 139,438		$ 143,930		$ 115,135
Basic earnings per share
Income from continuing operations (in dollars per share)	[1]									$ 1.89		$ 1.99		$ 1.65
Loss from discontinued operations (in dollars per share)	[1]									0.00		0.00		(0.03)
Net income per share (in dollars per share)		$ 0.60	$ 0.52	$ 0.38	$ 0.39	$ 0.52	$ 0.54	$ 0.54	$ 0.39	1.89	[1]	1.99	[1]	1.62	[1]
Diluted earnings per share
Income from continuing operations (in dollars per share)	[1]									1.88		1.98		1.64
Loss from discontinued operations (in dollars per share)	[1]									0.00		0.00		(0.03)
Net income per share (in dollars per share)		$ 0.59	$ 0.52	$ 0.38	$ 0.39	$ 0.52	$ 0.54	$ 0.54	$ 0.39	$ 1.88	[1]	$ 1.98	[1]	$ 1.61	[1]

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