Consolidated Statements of Shareholders' Equity (Parenthetical) (Parentheticals) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Consoldiated Statement of Shareholders' Equity (Parenthetical)
Dividends paid per Commons Share (in dollars per share)	$ 0.69	$ 0.68	$ 0.59
Common Stock, authorized (in shares)	60,000,000	60,000,000	60,000,000