Condensed Consolidated Statements of Changes in Equity (Unaudited) (Parenthetical) (Retained earnings, USD $)	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Retained earnings
Dividends per share	$ 0.11	$ 0.11

Aggregate dividends paid during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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