Selected Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended																12 Months Ended
	Dec. 31, 2020		Sep. 30, 2020		Jun. 30, 2020		Mar. 31, 2020		Dec. 31, 2019		Sep. 30, 2019		Jun. 30, 2019		Mar. 31, 2019		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Data [Abstract]
Revenues	$ 578,116		$ 579,136		$ 587,829		$ 605,017		$ 621,710		$ 631,579		$ 613,966		$ 610,667		$ 2,350,098	$ 2,477,922	$ 2,331,386
Operating Income	38,013		64,462		63,513		56,586		66,302		78,159		81,175		74,777		222,574	300,413	264,665
Net Income	11,884		39,172		36,654		25,121		38,042		45,885		41,836		40,649		112,831	166,412	144,827
Net income attributable to The GEO Group, Inc.	$ 11,911		$ 39,220		$ 36,720		$ 25,181		$ 38,052		$ 45,932		$ 41,914		$ 40,705		$ 113,032	$ 166,603	$ 145,089
Basic earnings per share:
Net income per share	$ 0.09		$ 0.33		$ 0.31		$ 0.21		$ 0.32		$ 0.39		$ 0.35		$ 0.34		$ 0.94	$ 1.40	$ 1.21
Diluted earnings per share:
Net income per share	$ 0.09	[1]	$ 0.33	[1]	$ 0.31	[1]	$ 0.21	[1]	$ 0.32	[1]	$ 0.39	[1]	$ 0.35	[1]	$ 0.34	[1]	$ 0.94	$ 1.40	$ 1.20

[1] Earnings per share table may contain slight summation differences due to rounding.