Divestitures (Details) - Import Stores Divested [Member] $ in Millions	3 Months Ended
Mar. 31, 2016 USD ($) stores	Mar. 31, 2015 USD ($) stores
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of stores divested \| stores	2	2
Gain on disposal \| $	$ 6.2	$ 1.4

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=51824106&loc=d3e2443-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51719941&loc=d3e2941-110230

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration