Condensed Consolidating Financial Information - Statement of Cash Flows (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2015
Cash Flow from Operating Activities:
Net cash provided by operating activities	$ 57,828	$ (11,758)
Cash Flow from Investing Activities:
Acquisition of CEC, net of cash acquired	(353,555)	0
Proceeds from sale of property and equipment	856	68
Insurance proceeds - damaged property	86	4,733	$ 4,733
Change in restricted cash and investments	(4,820)	(97,716)
Capital expenditures	(104,130)	(68,015)
Net cash used in investing activities	(461,563)	(160,930)
Cash Flow from Financing Activities:
Proceeds from long-term debt	1,324,865	813,077
Payments on long-term debt	(1,093,088)	(775,256)
Payments on non-recourse debt	(68,887)	(1,878)
Proceeds from non-recourse debt	123,785	273,087
Taxes paid related to net share settlements of equity awards	(4,122)	(2,336)
Proceeds from issuance of common stock in connection with ESPP	382	338
Proceeds from issuance of common stock under prospectus supplement	275,867	0
Debt issuance costs	(9,470)	(20,490)
Income tax deficiency related to equity compensation	0	(844)
Proceeds from the exercise of stock options	6,786	2,367
Cash dividends paid	(169,152)	(145,991)
Net cash provided by financing activities	386,966	142,074
Effect of Exchange Rate Changes on Cash and Cash Equivalents	257	1,099
Net Decrease in Cash and Cash Equivalents	(16,512)	(29,515)
Cash and Cash Equivalents, beginning of period	68,038	59,638
Cash and Cash Equivalents, end of period	51,526	30,123	59,638
The GEO Group, Inc.
Cash Flow from Operating Activities:
Net cash provided by operating activities	15,473	99,124
Cash Flow from Investing Activities:
Acquisition of CEC, net of cash acquired	(353,555)
Proceeds from sale of property and equipment	845	68
Insurance proceeds - damaged property	86		4,733
Change in restricted cash and investments	0	(24)
Capital expenditures	(34,679)	(9,879)
Net cash used in investing activities	(387,303)	(5,102)
Cash Flow from Financing Activities:
Proceeds from long-term debt	1,324,865	813,077
Payments on long-term debt	(1,093,088)	(775,256)
Payments on non-recourse debt	0	0
Proceeds from non-recourse debt	0	0
Taxes paid related to net share settlements of equity awards	(4,122)	(2,336)
Proceeds from issuance of common stock in connection with ESPP	0
Proceeds from issuance of common stock under prospectus supplement	275,867
Debt issuance costs	(8,701)	(16,980)
Income tax deficiency related to equity compensation		(844)
Proceeds from the exercise of stock options	6,786	2,367
Cash dividends paid	(169,152)	(145,991)
Net cash provided by financing activities	332,455	(125,963)
Effect of Exchange Rate Changes on Cash and Cash Equivalents	0	0
Net Decrease in Cash and Cash Equivalents	(39,375)	(31,941)
Cash and Cash Equivalents, beginning of period	45,566	37,077
Cash and Cash Equivalents, end of period	6,191	5,136	37,077
Combined Subsidiary Guarantors
Cash Flow from Operating Activities:
Net cash provided by operating activities	79,088	57,187
Cash Flow from Investing Activities:
Acquisition of CEC, net of cash acquired	0
Proceeds from sale of property and equipment	0	0
Insurance proceeds - damaged property	0		0
Change in restricted cash and investments	(4,645)	(2,635)
Capital expenditures	(61,432)	(54,552)
Net cash used in investing activities	(66,077)	(57,187)
Cash Flow from Financing Activities:
Proceeds from long-term debt	0	0
Payments on long-term debt	0
Payments on non-recourse debt	0	0
Proceeds from non-recourse debt	0	0
Taxes paid related to net share settlements of equity awards	0	0
Proceeds from issuance of common stock in connection with ESPP	0	0
Proceeds from issuance of common stock under prospectus supplement	0
Debt issuance costs	0	0
Income tax deficiency related to equity compensation		0
Proceeds from the exercise of stock options	0	0
Cash dividends paid		0
Net cash provided by financing activities	0	0
Effect of Exchange Rate Changes on Cash and Cash Equivalents	0	0
Net Decrease in Cash and Cash Equivalents	13,011	0
Cash and Cash Equivalents, beginning of period	842	0
Cash and Cash Equivalents, end of period	13,853	0	0
Combined Non-Guarantor Subsidiaries
Cash Flow from Operating Activities:
Net cash provided by operating activities	(36,733)	(168,069)
Cash Flow from Investing Activities:
Acquisition of CEC, net of cash acquired	0
Proceeds from sale of property and equipment	11	0
Insurance proceeds - damaged property	0		0
Change in restricted cash and investments	(175)	(95,057)
Capital expenditures	(8,019)	(3,584)
Net cash used in investing activities	(8,183)	(98,641)
Cash Flow from Financing Activities:
Proceeds from long-term debt	0	0
Payments on long-term debt	0	0
Payments on non-recourse debt	(68,887)	(1,878)
Proceeds from non-recourse debt	123,785	273,087
Taxes paid related to net share settlements of equity awards	0	0
Proceeds from issuance of common stock in connection with ESPP	382	338
Proceeds from issuance of common stock under prospectus supplement
Debt issuance costs	(769)	(3,510)
Income tax deficiency related to equity compensation		0
Proceeds from the exercise of stock options	0	0
Cash dividends paid	0	0
Net cash provided by financing activities	54,511	268,037
Effect of Exchange Rate Changes on Cash and Cash Equivalents	257	1,099
Net Decrease in Cash and Cash Equivalents	9,852	2,426
Cash and Cash Equivalents, beginning of period	21,630	22,561
Cash and Cash Equivalents, end of period	$ 31,482	$ 24,987	$ 22,561