Unaudited Condensed Consolidated Statements of Changes in Equity (Parenthetical) (USD $)	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Cash dividends on Class A and Class B common stock:	$ 1.0550	$ 1.0400

Aggregate dividends declared 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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Balance Type:	na
Period Type:	duration