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Commitments and Contingencies (Narrative) (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) lawsuit | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Loss Contingencies [Line Items] |  |  |
Rent expense | $ | $ 9,711 | $ 10,159 |
Number of lawsuits filed | 7 |  |
Cases with SPTC as Defendant |  |  |
Loss Contingencies [Line Items] |  |  |
Number of lawsuits filed | 4 |  |
Claims for Violations of Louisiana Racketeering Act |  |  |
Loss Contingencies [Line Items] |  |  |
Number of lawsuits filed | 2 |  |
Cases Remaining in Parish of East Baton Rouge Granted Indefinite Extensions to Respond |  |  |
Loss Contingencies [Line Items] |  |  |
Number of lawsuits filed | 2 |  |
Cases Filed in East Baton Rouge |  |  |
Loss Contingencies [Line Items] |  |  |
Number of lawsuits filed | 2 |  |
User licenses for software |  |  |
Loss Contingencies [Line Items] |  |  |
Rent expense | $ | $ 41,091 | $ 33,600 |
Rent expense | $ |  |  | $ 34,679

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