Inventories (Summary Of Inventory) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Finished products - FIFO basis	$ 188,771	$ 159,774
Less LIFO reserve - finished products	(131,505)	(102,849)
Finished products - LIFO basis	57,266	56,925
Store merchandise for resale	90,673	94,925
Materials and supplies	4,603	4,056
Total inventories	$ 152,542	$ 155,906

The amount of FIFO (first in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766

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Period Type:	instant

- References

No definition available.

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- Definition

Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

+ References

+ Details

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Balance Type:	credit
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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=68049868&loc=d3e3927-108312

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765

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- Definition

Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

+ References

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- Definition

The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

+ References

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- Definition

Carrying amount as of the balance sheet date of merchandise inventory purchased by a retailer, wholesaler or distributor and held for future sale.

+ References

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