Shareholders' Equity - Components of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Components of Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ 996,830
Current-period other comprehensive income (loss)	(13,164)	$ 2,252
Ending balance	958,346
Foreign currency translation adjustments, net of tax attributable to The GEO Group, Inc.
Components of Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(12,314)	(14,573)
Current-period other comprehensive income (loss)	(8,759)	1,736
Ending balance	(21,073)	(12,837)
Change in fair value of derivatives, net of tax
Components of Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(1,476)	(5,746)
Current-period other comprehensive income (loss)	(4,512)	1,164
Ending balance	(5,988)	(4,582)
Pension adjustments, net of tax
Components of Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(6,545)	(3,299)
Current-period other comprehensive income (loss)	107	(648)
Ending balance	(6,438)	(3,947)
Total
Components of Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(20,335)	(23,618)
Ending balance	$ (33,499)	$ (21,366)