Consolidated Statements Of Income (Parenthetical)	12 Months Ended
Dec. 31, 2010	Dec. 31, 2009
Adjusted to reflect common stock dividend paid to shareholders	2.00%	2.00%
Adjusted to reflect common stock dividend paid to shareholders record date	Oct. 03, 2011	Sep. 30, 2010
Dividend Paid [Member]
Adjusted to reflect common stock dividend paid to shareholders record date		Oct. 03, 2011

The date as of when a holder must own the stock to be entitled to the dividend. The ex-dividend date is generally 3 days before the record date.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration