Goodwill and Other Intangible Assets, Net (Goodwill) (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Nov. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Changes in the Company's goodwill balances
Beginning balance		$ 615,433	$ 615,438
Acquisitions (net of dispositions)		163,473	0
Foreign currency translation		45	(5)
Ending balance		778,951	615,433
U.S. Corrections & Detention
Changes in the Company's goodwill balances
Beginning balance		277,774	277,774
Acquisitions (net of dispositions)		39,231	0
Foreign currency translation		0	0
Ending balance		317,005	277,774
GEO Community Services
Changes in the Company's goodwill balances
Beginning balance		337,257	337,257
Acquisitions (net of dispositions)		124,242	0
Foreign currency translation		0	0
Ending balance		461,499	337,257
International Services
Changes in the Company's goodwill balances
Beginning balance		402	407
Acquisitions (net of dispositions)		0	0
Foreign currency translation		45	(5)
Ending balance		$ 447	$ 402
Assets Of One Of CEC Entities
Goodwill [Line Items]
Proceeds from sale of assets	$ 3,700
Goodwill decrease	$ 2,200

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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-Topic 350
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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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