Consolidated Statements of Changes in Stockholders' Equity Parenthetical (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Consolidated Statements of Changes in Stockholders' Equity [Abstract]
Currency translation adjustments, tax	$ 866	$ 153	$ 5,257

Tax effect of the adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into functional currency of the reporting entity.

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph c(3)

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 25

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