Summary of Business Organization, Operations and Significant Accounting Policies (Variable Interest Entities) (Details)	0 Months Ended	1 Months Ended		12 Months Ended							9 Months Ended							9 Months Ended	12 Months Ended		12 Months Ended			12 Months Ended
	Aug. 31, 2012 USD ($)	Feb. 28, 2011 USD ($) director	Aug. 31, 2010	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Jan. 03, 2010 Bed	Aug. 31, 2012	Aug. 30, 2012	Jan. 01, 2012 USD ($)	Sep. 30, 2014 GEO Amey USD ($)	Sep. 30, 2014 GEO Amey GBP (£)	Dec. 31, 2014 GEO Amey USD ($)	Dec. 31, 2014 GEO Amey GBP (£)	May 29, 2011 GEO Amey USD ($)	May 29, 2011 GEO Amey GBP (£)	Feb. 28, 2011 GEO Amey	Sep. 30, 2014 STLDC USD ($)	Dec. 31, 2013 STLDC	Sep. 30, 2013 STLDC USD ($)	Dec. 31, 2014 SACS	Dec. 31, 2014 GEO UK	Feb. 28, 2011 GEO UK	Dec. 31, 2014 Kensani Corrections	Dec. 31, 2013 Frio County, Texas STLDC Bed	Dec. 31, 2014 LIBOR GEO Amey	Dec. 31, 2014 Base Rate, Bank of England GEO Amey	Dec. 31, 2014 Other Noncurrent Assets GEO Amey USD ($)	Dec. 31, 2014 Other Noncurrent Assets GEO Amey GBP (£)
Variable Interest Entity [Line Items]
Number of beds							1,030																		1,904
Taxable revenue bond																				$ 49,500,000
Term of bonds																			10 years
Loss on early extinguishment of debt				0	(20,657,000)	(8,462,000)												(1,500,000)
Property and equipment, net				1,772,166,000	1,727,798,000					1,687,159,000
Stated interest rate			8.47%
Company lease assets term			20 years
Maximum period to lease renewal			25 years
Ownership percentage								100.00%	0.00%
Acquisition of ownership interests	35,154,000			0	0	35,154,000
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	8,100,000
Deferred tax assets recorded	10,015,000			0	0	10,015,000
Professional fees						1,600,000
Variable interest entity ownership percentage in joint venture				50.00%																		50.00%		50.00%
Life term of contract																					25 years
Reduction of Government Guarantee in Case of Default																					80.00%
Partnership Interest Share Amount		100
Units of Partnership Interest, Amount		100															50						50
Value Per Partnership Interest Shares		$ 1
Directors appointed to board by each party		3
Debt instrument basis spread on variable rate																										3.00%	0.50%
Line of Credit, amount outstanding				70,000,000	340,000,000								18,600,000	12,000,000	18,600,000	12,000,000
Accrued interest included under line of credit											1,500,000	900,000
Due from joint venture, current																												$ 16,300,000	£ 10,500,000