Summary of Business Organization, Operations and Significant Accounting Policies - Additional Information (Details Textual) detainee in Thousands, bed in Thousands, $ in Thousands, £ in Millions	1 Months Ended		12 Months Ended
	Jan. 31, 2018 USD ($)	Mar. 31, 2017	Dec. 31, 2017 USD ($) person facility detainee bed Bed	Dec. 31, 2017 GBP (£) person facility detainee bed Bed	Dec. 31, 2016 USD ($)	Dec. 31, 2016 GBP (£)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Summary of Business Organization
Number of beds | bed			96	96
Correctional, detention and residential treatment facilities including projects under development | facility			141	141
Provision of monitoring services tracking offenders (more than 139,000 offenders) | person			192,000	192,000
Provision of monitoring services tracking offenders using technology products | detainee			100	100
Cash and Cash Equivalents
Cash and cash equivalents			$ 81,377		$ 68,038		$ 59,638	$ 41,337
Accounts Receivable
Minimum period for payment receivable in arrears for services			30 days
Maximum period for payment receivable in arrears for services			60 days
Notes Receivable
Interest rate for subordinated loan extended to the former joint venture partner			13.00%
Line of Credit, amount outstanding			$ 270,559		515,000
Federal and state income tax overpayments			15,500		9,400
Property and Equipment
Assets held for sale			3,915		0
Asset Impairments
Property and equipment, net			$ 2,078,123		1,897,241		1,916,386
Number of vacant beds at its idle facilities | Bed			5,400	5,400
Number of marketed idle facilities | facility			5	5
Carrying values of idle facilities			$ 139,600
Other Intangible Assets
Amortization period			1 year
Debt Issuance Costs
Deferred debt issuance cost, accumulated amortization			$ 49,800		40,200
Debt issuance costs included in other non-current assets			$ 42,300		48,900
Revenue based on performance of certain targets			1.00%
Capitalized Computer Software, Net			$ 30,100		21,200
Facility management contracts
Other Intangible Assets
Amortization period			16 years 3 months
Foreign Subsidiaries
Cash and Cash Equivalents
Cash and cash equivalents			$ 28,200		21,600
GEO Amey
Summary of Business Organization
Ownership percentage			50.00%	50.00%
Notes Receivable
Line of Credit, amount outstanding			$ 16,200	£ 12.0
Minimum
Property and Equipment
Useful life			1 year
Minimum | Facility management contracts
Other Intangible Assets
Amortization period			3 years
Minimum | Technology
Other Intangible Assets
Amortization period			7 years
Maximum | Facility management contracts
Other Intangible Assets
Amortization period			21 years
Maximum | Technology
Other Intangible Assets
Amortization period			8 years
Building and Building Improvements | Minimum
Property and Equipment
Useful life			2 years
Building and Building Improvements | Maximum
Property and Equipment
Useful life			50 years
Equipment and Furniture and Fixtures | Minimum
Property and Equipment
Useful life			3 years
Equipment and Furniture and Fixtures | Maximum
Property and Equipment
Useful life			10 years
LIBOR | GEO Amey
Notes Receivable
Principal amount and accrued interest at LIBOR			0.50%
Cornell Companies, Inc.
Accounts Receivable
Accounts receivable one year past due and still accruing			1 year
Other Noncurrent Assets
Accounts Receivable
Trade receivables			$ 4,000		1,300
Other Noncurrent Assets | GEO Amey
Notes Receivable
Due from joint venture, current			$ 1,700	£ 1.3
Due from joint venture, non-current					4,300	£ 3.5
The GEO Group Australia | Ravenhall
Notes Receivable
Facility, number of beds | Bed			1,300	1,300
Common Stock
Summary of Business Organization
Stock split, conversion ratio		1.5
AUSTRALIA
Asset Impairments
Property and equipment, net			$ 16,281		$ 10,053		$ 5,871
AUSTRALIA | Foreign Tax Authority
Notes Receivable
Federal and state income tax overpayments			$ 13,000
Subsequent Event
Property and Equipment
Proceeds from sale of property held-for-sale	$ 4,000