Quarterly Operating Results (Unaudited) (Tables)	12 Months Ended
Dec. 31, 2012
Quarterly Operating Results (Unaudited) [Abstract]
Summary of operating results by quarter	Summary of operating results by quarter

Tabular disclosure of the quarterly financial data in the annual financial statements. The disclosure includes financial information for each fiscal quarter for the current and previous year, including revenues, gross profit, income (loss) before extraordinary items and cumulative effect of a change in accounting principle and earnings per share data.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 270

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)-(j)

-URI http://asc.fasb.org/extlink&oid=20225539&loc=d3e1280-108306

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Balance Type:	na
Period Type:	duration