Commitments, Contingencies and Other (Details) $ in Millions	6 Months Ended
	Jun. 30, 2017 USD ($) facility bed	Feb. 08, 2017 USD ($)	Oct. 22, 2014 detainee
Commitments and Contingencies [Line Items]
Number of current and former civil immigration detainees | detainee			9
Estimate of possible loss	$ 19.6
Estimated construction capital project cost	196.3
Cost already spent on existing capital projects	46.8
Remaining capital required for capital projects	$ 149.5
Number of vacant beds at idle facilities marketed to potential customers | bed	6,600
Number of marketed idle facilities | facility	6
Property and Equipment
Commitments and Contingencies [Line Items]
Carrying values of idle facilities marketed to potential customers	$ 164.2
Pending Litigation | Attorney General of Mississippi vs Company, Cornell Companies, Inc., Christopher B Epps And Cecil McCrory
Commitments and Contingencies [Line Items]
Contracts disputed		$ 256.0