Loans and Allowance for Credit Losses Troubled Debt Restructurings (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	$ 60,558	$ 67,621
Non-accrual TDRs	31,035	24,616
Total TDRs	91,593	92,237
Residential Mortgage
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	28,511	31,308
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	17,563	18,822
Construction - commercial residential
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	3,942	9,241
Commercial - secured
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	5,833	5,170
Real estate – home equity
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	4,556	2,975
Commercial - unsecured
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	120	67
Consumer - direct
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	19	19
Consumer - indirect:
Financing Receivable, Modifications [Line Items]
Total accruing TDRs	$ 14	$ 19