Loans, Troubled Debt Restructuring (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($) Loan	Sep. 30, 2016 USD ($) Loan	Sep. 30, 2017 USD ($) Loan	Sep. 30, 2016 USD ($) Loan
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans | Loan	0	3	2	8
Pre-Modification Recorded Balance	$ 0	$ 342,000	$ 32,000	$ 713,000
Post-Modification Recorded Balance	0	$ 342,000	$ 23,000	786,000
Troubled debt restructurings that subsequently defaulted within 12 months of the restructuring date	$ 1,236,000			$ 0
Commercial and industrial [Member]
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans | Loan	0	0	0	0
Pre-Modification Recorded Balance	$ 0	$ 0	$ 0	$ 0
Post-Modification Recorded Balance	$ 0	$ 0	$ 0	$ 0
Commercial, secured by real estate [Member]
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans | Loan	0	1	0	2
Pre-Modification Recorded Balance	$ 0	$ 304,000	$ 0	$ 603,000
Post-Modification Recorded Balance	$ 0	$ 304,000	$ 0	$ 676,000
Residential real estate [Member]
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans | Loan	0	1	1	3
Pre-Modification Recorded Balance	$ 0	$ 27,000	$ 18,000	$ 72,000
Post-Modification Recorded Balance	$ 0	$ 27,000	$ 9,000	$ 72,000
Consumer [Member]
Loan modifications classified as troubled debt restructurings [Abstract]
Number of Loans | Loan	0	1	1	3
Pre-Modification Recorded Balance	$ 0	$ 11,000	$ 14,000	$ 38,000
Post-Modification Recorded Balance	$ 0	$ 11,000	$ 14,000	$ 38,000