Loans, Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) loan	Dec. 31, 2015 USD ($) loan	Dec. 31, 2014 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	131	211	309
Recorded Investment	$ 9,270	$ 41,131	$ 38,870
Unpaid Principal Balance	$ 9,631	$ 42,765	$ 40,660
Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	8	12	15
Recorded Investment	$ 1,509	$ 2,219	$ 7,681
Unpaid Principal Balance	$ 1,526	$ 2,900	$ 7,711
Commercial real estate — owner occupied
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	1	5	4
Recorded Investment	$ 116	$ 3,694	$ 1,465
Unpaid Principal Balance	$ 122	$ 3,901	$ 1,625
Commercial real estate — investor
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	0	5	6
Recorded Investment	$ 0	$ 21,573	$ 6,097
Unpaid Principal Balance	$ 0	$ 21,640	$ 6,521
Real estate construction
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	1	4	2
Recorded Investment	$ 65	$ 78	$ 15
Unpaid Principal Balance	$ 91	$ 79	$ 15
Residential mortgage
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	63	97	163
Recorded Investment	$ 5,535	$ 10,464	$ 19,675
Unpaid Principal Balance	$ 5,792	$ 10,996	$ 20,454
Home equity
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	57	88	117
Recorded Investment	$ 2,030	$ 3,103	$ 3,913
Unpaid Principal Balance	$ 2,084	$ 3,249	$ 4,308
Other consumer
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	1	0	2
Recorded Investment	$ 15	$ 0	$ 24
Unpaid Principal Balance	$ 16	$ 0	$ 26