Basis of Presentation (Details) detainee in Thousands, bed in Thousands	1 Months Ended
	Mar. 31, 2017	Sep. 30, 2017 facility detainee bed	Dec. 31, 2016 detainee
Class of Stock [Line Items]
Number of beds | bed		96
Correctional, detention and residential treatment facilities including projects under development | facility		140
Provision of monitoring services tracking offenders (more than 185,000)		185
Provision of monitoring services tracking offenders using technology products (in detainees)			100
Common shares
Class of Stock [Line Items]
Stock split, conversion ratio	1.5