Loans and Allowance for Credit Losses Loans Modified Under Troubled Debt Restructurings (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	$ 67,684		$ 68,111
Non-accrual TDRs	27,487	[1]	30,209	[1]
Total TDRs	95,171		98,320
Real-estate - residential mortgage [Member]
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	30,363		28,815
Real-estate commercial mortage [Member]
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	19,514		19,758
Commercial - Secured [Member]
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	6,674		7,933
Construction - Commercial Residential [Member]
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	8,430		10,117
Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	2,606		1,365
Commercial - unsecured [Member]
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	81		112
Consumer Other Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	$ 1		$ 0

[1] Included within non-accrual loans in the preceding table detailing non-performing assets.