Summary of Business Organization, Operations and Significant Accounting Policies - Additional Information (Details Textual) person in Thousands, detainee in Thousands, bed in Thousands, $ in Thousands, £ in Millions	1 Months Ended		9 Months Ended	12 Months Ended
	Jan. 31, 2018 USD ($)	Mar. 31, 2017	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($) person facility detainee bed property Bed	Dec. 31, 2017 USD ($) property	Dec. 31, 2016 USD ($)	Dec. 31, 2018 GBP (£) person facility detainee bed property Bed	Dec. 31, 2017 GBP (£) property
Summary of Business Organization
Number of beds | bed				96			96
Correctional, detention and residential treatment facilities including projects under development | facility				135			135
Provision of monitoring services tracking offenders (more than 139,000 offenders) | person				210			210
Provision of monitoring services tracking offenders using technology products | detainee				100			100
Stock split, conversion ratio				1.5
Cash and Cash Equivalents
Cash and cash equivalents				$ 31,255	$ 81,377	$ 68,038
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				$ 490,843	270,559
Federal and state income tax overpayments				$ 6,100	$ 15,500
Property and Equipment
Assets held for sale, number of properties | property				2	1		2	1
Assets held for sale				$ 2,634	$ 3,915
Proceeds from sale of assets held for sale	$ 4,000		$ 3,797	3,797	0	0
Asset Impairments
Property and equipment, net				$ 2,158,610	2,078,123	1,897,241
Number of vacant beds at its idle facilities | Bed				4,700			4,700
Number of marketed idle facilities | facility				4			4
Carrying values of idle facilities				$ 126,000
Debt Issuance Costs
Deferred debt issuance cost, accumulated amortization				65,700	49,800
Debt issuance costs included in other non-current assets				31,100	42,300
Capitalized Computer Software, Net				$ 29,600	30,100
Facility management contracts
Other Intangible Assets
Amortization period				16 years 3 months
Foreign Subsidiaries
Cash and Cash Equivalents
Cash and cash equivalents				$ 18,900	28,200
GEO Amey
Summary of Business Organization
Ownership percentage				50.00%			50.00%
Notes Receivable
Line of Credit, amount outstanding				$ 15,300			£ 12.0
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
Parcel Of Undeveloped Land
Property and Equipment
Assets held for sale				$ 700
Idle Reentry Facility
Property and Equipment
Assets held for sale				$ 1,900
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				$ 2,300	4,000
Other Noncurrent Assets | GEO Amey
Notes Receivable
Due from joint venture, current					1,700			£ 1.3
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				$ 13,006	$ 16,281	$ 10,053
AUSTRALIA | Foreign Tax Authority
Notes Receivable
Federal and state income tax overpayments				$ 13,000
GEO Care
Asset Impairments
Number of marketed idle facilities | facility				3			3
Carrying values of idle facilities				$ 23,400