Equity Investment - Additional Information (Detail) (Exego Group [Member], USD $)	12 Months Ended
Dec. 31, 2012 Store
Exego Group [Member]
Schedule of Equity Method Investments [Line Items]
Cash paid for acquisition	$ 165,600,000
Percentage of investment acquired	30.00%
Annual revenue	$ 1,000,000,000
Company-owned stores across Australia and New-Zealand	430
Percentage available for option to acquire remaining part	70.00%

Percentage of voting equity interests acquired in the business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7659399&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Balance Type:	na
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