Goodwill and Other Intangible Assets - Goodwill (Details) $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning of period	$ 778,951
Acquisition Adjustments	(2,549)
Foreign Currency Translation	(34)
Goodwill, end of period	776,368
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	(34)
Goodwill, end of period	$ 413

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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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