CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) (USD $)	1 Months Ended	12 Months Ended
Feb. 12, 2012	Feb. 09, 2011	Feb. 10, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN SHAREHOLDERS' EQUITY
Dividends per common share (in dollars per share)	$ 0.18	$ 0.165	$ 0.15	$ 0.165	$ 0.15	$ 0

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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Namespace Prefix:	us-gaap_
Data Type:	us-types:perShareItemType
Balance Type:	na
Period Type:	duration