v3.19.1

Derivative Financial Instruments (Schedule Of NYMEX Contracts And Butane Price Swap Purchase Agreements) (Details) bbl in Millions	Mar. 31, 2019 bbl
Economic Hedges [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	3.3
Economic Hedges Futures [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0.6

X

- Definition

Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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Period Type:	instant

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

X

- Details

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Namespace Prefix:
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X

- Details

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