Goodwill and Other Intangible Assets - Goodwill (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning of period	$ 778,951
Acquisition Adjustments	(2,549)
Foreign Currency Translation	(7)
Goodwill, end of period	776,395
U.S. Corrections & Detention
Goodwill [Roll Forward]
Goodwill, beginning of period	317,005
Acquisition Adjustments	(639)
Foreign Currency Translation	0
Goodwill, end of period	316,366
GEO Care
Goodwill [Roll Forward]
Goodwill, beginning of period	461,499
Acquisition Adjustments	(1,910)
Foreign Currency Translation	0
Goodwill, end of period	459,589
International Services
Goodwill [Roll Forward]
Goodwill, beginning of period	447
Acquisition Adjustments	0
Foreign Currency Translation	(7)
Goodwill, end of period	$ 440

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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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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