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Commitments and Contingencies (Details) | Mar. 31, 2018 Lawsuit
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Loss Contingencies [Line Items] |
Number of lawsuits filed | 7
Cases with SPTC as Defendant [Member] |
Loss Contingencies [Line Items] |
Number of lawsuits filed | 4
Claims for Violations of Louisiana Racketeering Act [Member] |
Loss Contingencies [Line Items] |
Number of lawsuits filed | 2
Cases Remaining in Parish Of East Baton Rouge Granted Indefinite Extensions to Respond [Member] |
Loss Contingencies [Line Items] |
Number of lawsuits filed | 2
Cases Filed in East Baton Rouge [Member] |
Loss Contingencies [Line Items] |
Number of lawsuits filed | 2

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