Allowance for Loan and Lease Losses Allowance for Loan and Lease Losses (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for acquired loan losses	$ 6,800,000
Provision for Loan Lease and Other Losses Covered		20,722,000	20,353,000
Minimum Non Performing Substandard Loans Outstanding for Allowance for Credit Losses	300,000
Minimum Non Performing Substandard Doubtful Loans Outstanding for Allowance for Credit Losses	100,000
Loan Commitments	5,546,635,000	4,151,541,000
Total impaired loans with no related allowance
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Commitments	200,000
Acquired Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Allowance for Credit Losses	741,000
Covered Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for Loan Losses Before Benefit Attributable to FDIC Loss Share Agreements	23,892,000	35,450,000
Allowance for Loan and Lease Losses, Write-offs	23,120,000	28,612,000
Benefit Attributable to FDIC Loss Share Agreements	10,790,000	14,728,000
Provision for Loan Lease and Other Losses Covered	$ 13,102,000	$ 20,722,000