Consolidated Statements of Changes in Equity (Parenthetical) (USD $)	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Consolidated Statements of Changes in Equity
Cash dividends paid, per share	$ 0.46	$ 0.448

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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