Consolidated Balance Sheet (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Held to Maturity, Fair value	$ 2,943.3	$ 2,394.8
Total Loans and Leases, unearned income	$ 286.6	$ 297.9
Common Stock, Par Value	$ 1.6667	$ 1.6667
Common Stock, Authorized	560,000,000	560,000,000
Common Stock, Outstanding	239,239,836	238,914,988
Treasury Stock, shares	5,931,688	6,256,536