Consolidated Statements of Shareholders' Equity (unaudited) (Parenthetical) (USD $)	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Consolidated Statements of Shareholders' Equity (unaudited) [Abstract]
Cash Dividends per share (in dollars per share)	$ 0.36	$ 0.36

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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Period Type:	duration