Discontinued Operations (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended	3 Months Ended					12 Months Ended		3 Months Ended
	Dec. 31, 2012	Apr. 01, 2012 RTS	Apr. 01, 2012 MDOC	Jul. 19, 2012 East Mississippi Correctional Facility bed	Aug. 13, 2012 Marshall County Correctional Facility bed	Jul. 01, 2012 Walnut Grove Youth Correctional Facility bed	Dec. 31, 2012 Services Agreement	Dec. 31, 2012 License Agreement	Mar. 31, 2013 Services and Licensing Agreement
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross Sale Price of RTS	$ 36.0
Proceeds from Divestiture of Businesses	33.6
Period of Working Capital Adjustment After Divestiture	0 years 0 months 105 days
Proceeds From Divestiture of Business, Final	32.3
Long-Term Purchase Commitment, Earn-Out	5.0
Sales Revenue, Services, Other							1.8
Licensing Agreement Contract Term								5 years
Services Agreement Contract Term								5 years
Licenses Revenue								0.4
Sales Service Revenue Other and License Revenue									0.6
Number of beds discontinued				1,500	1,000	1,450
Disposal Group, Including Discontinued Operation, Revenue		41.2	11.1
Disposal Group, Including Discontinued Operation, Operating Income (Loss)		$ 2.0	$ 0.1