Allowance for Loan Losses, Loans Modified or Renewed (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Financing Receivable, Modifications [Line Items]
Number of loans	47	5
Outstanding recorded balance	$ 48,115	$ 1,599
Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of loans	13	0
Outstanding recorded balance	8,111	0
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of loans	34	5
Outstanding recorded balance	$ 40,004	$ 1,599