Earnings Per Share - Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share Basic And Diluted [Abstract]
Net income	$ 25,121	$ 40,649
Net loss attributable to noncontrolling interests	60	56
Net income attributable to The GEO Group, Inc.	$ 25,181	$ 40,705
Basic earnings per share attributable to The GEO Group, Inc.:
Weighted average shares outstanding (in shares)	119,394	118,774
Per share amount (in dollars per share)	$ 0.21	$ 0.34
Diluted earnings per share attributable to The GEO Group, Inc.:
Weighted average shares outstanding (in shares)	119,394	118,774
Dilutive effect of equity incentive plans (in shares)	539	722
Weighted average shares assuming dilution (in shares)	119,933	119,496
Per share amount (in dollars per share)	$ 0.21	$ 0.34