Commitments, Contingencies and Other (Details) bed in Thousands, $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($) facility bed	Dec. 19, 2017 claim
Commitments and Contingencies [Line Items]
Estimate of possible loss	$ 19.6
Estimated construction capital project cost	218.0
Cost already spent on existing capital projects	195.0
Remaining capital required for capital projects	$ 23.0
Number of vacant beds at idle facilities marketed to potential customers \| bed	4
Number of marketed idle facilities \| facility	4
Property and Equipment
Commitments and Contingencies [Line Items]
Carrying values of idle facilities marketed to potential customers	$ 110.0
Pending Litigation \| Immigration Detainees Against Company
Commitments and Contingencies [Line Items]
New claims filed, number \| claim		3
WASHINGTON \| Pending Litigation \| Immigration Detainees Against Company
Commitments and Contingencies [Line Items]
New claims filed, number \| claim		2
CALIFORNIA \| Pending Litigation \| Immigration Detainees Against Company
Commitments and Contingencies [Line Items]
New claims filed, number \| claim		1

Carrying Values of Idle Facilities Marketed to Potential Customers

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Commitments and Contingencies.

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Number of Marketed Idle Facilities

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Number of Vacant Beds at Idle Facilities Marketed to Potential Customers

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Estimated amount of loss resulting from an adverse tax position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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The total number of new claims filed pertaining to a loss contingency during the period.

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-Publisher FASB
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