Loans and Credit Quality - Nonaccrual Loans By Segment (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	$ 13,893	$ 3,686
Government guarantees on nonaccrual loans	(1,413)	(1,561)
Net nonaccrual loans	12,480	2,125
Commercial
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	13,500	3,013
Real estate term owner occupied
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	29	38
Real estate term non-owner occupied
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	197	359
Consumer secured by 1st deeds of trust
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	167	256
Consumer other
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	0	20
30-59 Days Past Due
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	8,750	0
Government guarantees on nonaccrual loans	0	0
Net nonaccrual loans	8,750	0
30-59 Days Past Due | Commercial
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	8,750	0
30-59 Days Past Due | Real estate term owner occupied
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	0	0
30-59 Days Past Due | Real estate term non-owner occupied
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	0	0
30-59 Days Past Due | Consumer secured by 1st deeds of trust
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	0	0
30-59 Days Past Due | Consumer other
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans		0
60-89 Days Past Due
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	0	82
Government guarantees on nonaccrual loans	0	0
Net nonaccrual loans	0	82
60-89 Days Past Due | Commercial
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	0	82
60-89 Days Past Due | Real estate term owner occupied
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	0	0
60-89 Days Past Due | Real estate term non-owner occupied
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	0	0
60-89 Days Past Due | Consumer secured by 1st deeds of trust
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	0	0
60-89 Days Past Due | Consumer other
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans		0
Greater Than 90 Days Past Due
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	4,375	418
Government guarantees on nonaccrual loans	(1,413)	0
Net nonaccrual loans	2,962	418
Greater Than 90 Days Past Due | Commercial
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	4,208	290
Greater Than 90 Days Past Due | Real estate term owner occupied
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	0	0
Greater Than 90 Days Past Due | Real estate term non-owner occupied
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	0	108
Greater Than 90 Days Past Due | Consumer secured by 1st deeds of trust
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	167	0
Greater Than 90 Days Past Due | Consumer other
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans		20
Current
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	768	3,186
Government guarantees on nonaccrual loans	0	(1,561)
Net nonaccrual loans	768	1,625
Current | Commercial
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	542	2,641
Current | Real estate term owner occupied
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	29	38
Current | Real estate term non-owner occupied
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	197	251
Current | Consumer secured by 1st deeds of trust
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans	$ 0	256
Current | Consumer other
Nonaccrual Loans By Major Loan Type [Line Items]
Total nonaccrual loans		$ 0