Business Segments and Geographic Information - Operating and Reporting Segments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenues:
Revenues	$ 583,530	$ 566,759	$ 1,731,956	$ 1,694,443
Operating Income:
Operating income	69,780	62,902	201,181	181,827
U.S. Corrections & Detention
Revenues:
Revenues			1,107,016	1,073,840
GEO Care
Revenues:
Revenues			431,819	377,740
International Services
Revenues:
Revenues			193,121	130,261
Operating Segments
Revenues:
Revenues	583,530	566,759	1,731,956	1,694,443
Operating Income:
Operating income	117,427	111,976	338,108	325,693
Operating Segments | U.S. Corrections & Detention
Revenues:
Revenues	379,351	365,071	1,107,016	1,073,840
Operating Income:
Operating income	77,885	77,551	224,386	224,838
Operating Segments | GEO Care
Revenues:
Revenues	141,808	134,610	431,819	377,740
Operating Income:
Operating income	35,959	31,293	102,795	94,062
Operating Segments | International Services
Revenues:
Revenues	62,371	45,641	193,121	130,261
Operating Income:
Operating income	3,583	3,410	10,927	8,413
Operating Segments | Facility Construction and Design
Revenues:
Revenues	0	21,437	0	112,602
Operating Income:
Operating income	$ 0	$ (278)	$ 0	$ (1,620)