Debt (Guarantees) (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013 USD ($)	Dec. 31, 2013 ZAR	Dec. 31, 2014 GEO Amey USD ($)	Dec. 31, 2014 Ravenhall USD ($) guarantee	Dec. 31, 2014 SACS USD ($)	Dec. 31, 2014 SACS ZAR	Dec. 31, 2014 Canada Facility USD ($)	Dec. 31, 2014 Canada Facility CAD	Dec. 31, 2014 Revolver Letter of credit Ravenhall AUD	Sep. 30, 2014 Revolver Letter of credit Ravenhall USD ($)	Dec. 31, 2014 Other Noncurrent Assets GEO Amey USD ($)	Dec. 31, 2014 Other Noncurrent Assets GEO Amey GBP (£)
Debt Instrument [Line Items]
Maximum exposure, undiscounted				60,000,000			$ 2,300,000	26,700,000			214,000,000	$ 174,600,000
Number of letters of guarantee outstanding under separate international facilities relating to performance guarantees						9
Letters of guarantee outstanding relating to performance guarantees						12,400,000
Percentage of amount payable guaranteed by Company	60.00%	60.00%
Stand by letters of credit provided as security for guarantee				8,400,000
Maximum loan amount under stand by facility to SACS							1,723,800.0	20,000,000
Potential estimated exposure of tax obligations									2,200,000	2,500,000
Liability related to potential tax exposure			2,000,000						2,000,000
Variable interest entity ownership percentage in joint venture	50.00%	50.00%
Lines of credit					12,000,000
Due from joint venture, current													$ 16,300,000	£ 10,500,000