Mortgage Banking and Servicing Rights (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Mortgage Banking and Servicing Rights [Abstract]
Net gain on sale of loans held for sale		$ 1,831	$ 1,978	$ 1,468
Net loan servicing income (expense) [Abstract]
Servicing fees		1,239	1,197	1,129
Late fees		78	88	112
Ancillary fees		322	212	149
Fair value adjustments		(324)	(289)	(830)
Net loan servicing income		1,315	1,208	560
Mortgage banking income		3,146	3,186	2,028
Loan service for benefit of others		466,000	458,000	441,000
Custodial escrow balance		1,000	1,000	900
Activity for capitalized mortgage servicing rights using fair value method [Roll Forward]
Fair value of MSRs, beginning of period		3,236	2,968	3,424
New servicing assets created		521	557	374
Change in fair value during the period due to [Abstract]
Time decay	[1]	(175)	(168)	(162)
Payoffs	[2]	(313)	(247)	(202)
Changes in valuation inputs or assumptions	[3]	164	126	(466)
Fair value of MSRs, end of period		$ 3,433	$ 3,236	$ 2,968
Discount rate of servicing assets and servicing liabilities		10.10%	10.10%	10.10%
Weighted average default rates		3.02%	2.64%	3.61%
Prepayment speeds generated using Andrew Davidson Prepayment Model		9.50%	10.00%	11.30%

[1] Represents decrease in value due to regularly scheduled loan principal payments and partial loan paydowns.

[2] Represents decrease in value due to loans that paid off during the period.

[3] Represents change in value resulting from market-driven changes in interest rates.