Contractual interest rate for funds borrowed, under the debt agreement.

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Debt (Nonrecourse Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Debt Instrument [Line Items]
Long term debt	$ 2,629,010	$ 2,561,881
Restricted cash and cash equivalents - current	30,201		$ 27,229
Non Recourse Debt 2011 Revenue Bonds
Debt Instrument [Line Items]
Long term debt	$ 54,400
Stated interest rate	5.25%
Non Recourse Debt 2011 Revenue Bonds \| Northwest Detention Center
Debt Instrument [Line Items]
Non-recourse debt	$ 8,100
Non Recourse Debt Northwest Detention Center \| Northwest Detention Center
Debt Instrument [Line Items]
Restricted cash and cash equivalents - current	$ 8,600