Condensed Consolidated Statement Of Stockholders' Equity (Parenthetical) (USD $)	6 Months Ended
Jun. 30, 2011
Condensed Consolidated Statement Of Stockholders' Equity
Dividends to common stockholders, per share	$ 1.23

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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Data Type:	us-types:perShareItemType
Balance Type:	na
Period Type:	duration