Loans Details Narrative (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual Non-reaffirmed Bankruptcies	$ 8,800,000		$ 8,800,000		$ 7,700,000
Provision for loan and lease losses - acquired loans	2,033,000	0	2,033,000	0
Consumer Loans Guaranteed by Government	2,900,000	3,100,000	2,900,000	3,100,000	3,400,000
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums	7,500,000	(5,800,000)	7,500,000	(5,800,000)	(6,500,000)
Loans Due Ninety Days or More or on Nonaccrual Status			90 days
Days past due for nonaccrual status credit card loans			120 days
Loans	14,269,166,000	9,491,349,000	14,269,166,000	9,491,349,000	9,750,784,000
Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	4,200,000,000		4,200,000,000
Covered Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Covered Loans Loss Share Receivable		131,900,000		131,900,000	113,700,000
Provision for Loan Losses Before Benefit Attributable to FDIC Loss Share Agreements	2,855,000	7,698,000	19,009,000	28,177,000
Provision for Loan Lease and Other Losses Covered	1,823,000	6,214,000	10,119,000	15,576,000
Covered Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Reclassifications from Nonaccretable Difference	12,745,000	6,008,000	28,726,000	30,814,000
Covered Loans | Covered Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Covered Loans Loss Share Receivable	69,986,000		69,986,000
Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 3,825,751,000		$ 3,825,751,000