Inventories (Tables)	3 Months Ended
Mar. 31, 2013
Inventories [Abstract]
Summary of inventories	Summary of inventories

Tabular disclosure of the carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 2

-Paragraph 6

-Subparagraph a,b,c

-Article 5

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