Goodwill - Additional Information (Detail)	3 Months Ended			12 Months Ended
	Sep. 30, 2017 Facility	Mar. 31, 2017 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2017 USD ($) Facility	Dec. 31, 2016 USD ($)
Goodwill and Intangible Assets Disclosure [Line Items]
Establishment of goodwill				This goodwill was established in connection with multiple business combination transactions.
Goodwill				$ 40,927,000	$ 38,386,000
Goodwill impairment charges				0
State of Texas
Goodwill and Intangible Assets Disclosure [Line Items]
Goodwill				$ 0
Number of facilities scheduled to expire in August 2017 | Facility				4
Number of facilities for which TDCJ selected other operators | Facility	3
Bartlett State Jail
Goodwill and Intangible Assets Disclosure [Line Items]
Goodwill impairment charges		$ 300,000
Closing date of Bartlett facility				Jun. 24, 2017
Winn Correctional Center
Goodwill and Intangible Assets Disclosure [Line Items]
Goodwill impairment charges			$ 1,000,000