Loans and Allowance for Loan Losses (Average Impaired Loans) (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2011	Dec. 31, 2010
Non-accrual loans	$ 76,287	$ 78,239
Restructured loans	64,515	65,236
Total	140,802	143,475	173,000
Commercial [Member]
Non-accrual loans	68,554	70,962
Restructured loans	41,993	43,652
Total	110,547	114,614
Personal Banking [Member]
Non-accrual loans	7,733	7,277
Restructured loans	22,522	21,584
Total	$ 30,255	$ 28,861