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Commitments and Contingencies (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) Lawsuit	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Rent expense | $	$ 34,679	$ 32,619	$ 28,016
Loss Contingencies [Line Items]
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

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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Number of pending claims pertaining to a loss contingency.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

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