Supplemental Compensation Plans (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014 Participant	Dec. 31, 2013	Dec. 31, 2012
Salary Continuation Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Duration for benefit payment after retirement age	10 years
Retirement age	65 years
Reduced benefit age	55 years
Years of services for reduced benefit	10 years
Number of participants in SERP plan	3
Average years of salary used for benefit calculation	3 years
Average years of bonus used for benefit calculation	7 years
Percentage of average compensation for executive (in hundredths)	2.00%
Percentage of average compensation for CEO (in hundredths)	2.50%
Target service years for executive	25 years
Target service years for CEO	20 years
Target benefit of average compensation (in hundredths)	50.00%
Reduction made for social security benefit (in hundredths)	50.00%
Expected age of social security benefit	65 years
Number of years average yields of treasury securities	3 years
Treasury securities duration	10 years
Period of monthly retirement benefit payment	120 months
Additional months for retirement payment for full year of service	6 months
Number of full service years used to calculate additional retirement payment	10 years
Maximum period for monthly retirement payment	180 months
Reduction in benefit for retirement prior to retirement age (in hundredths)	5.00%
Benefit reduction for retirement at age 55 (in hundredths)	50.00%
Early retirement age	55 years
Benefit payable for voluntary terminations prior to age 55 (in hundredths)	0.00%
Change in benefit obligation [Roll Forward]
Benefit obligation at beginning of year	$ 3,515	$ 3,590	$ 3,132
Service cost	150	170	146
Interest cost	154	117	124
Plan loss (gain)	433	(186)	364
Benefits paid	(176)	(176)	(176)
Benefit obligation at end of year	4,076	3,515	3,590
Change in plan assets [Abstract]
Employer Contribution	176	176	176
Benefits paid	(176)	(176)	(176)
Fair value of plan assets at end of year	0	0	0
Reconciliation of funded status [Abstract]
Funded status	(4,076)	(3,515)	(3,590)
Unrecognized net plan loss	877	459	683
Unrecognized prior service cost	252	340	429
Net amount recognized	(2,947)	(2,716)	(2,478)
Amounts recognized in the consolidated balance sheets consist of [Abstract]
Accrued benefit liability	(4,076)	(3,515)	(3,590)
Accumulated other comprehensive income	1,129	799	1,112
Net amount recognized	(2,947)	(2,716)	(2,478)
Components of net periodic benefit cost [Abstract]
Service cost	150	170	146
Interest cost	154	117	124
Amortization of prior service cost	88	88	88
Recognized actuarial (gain)loss	14	38	0
Net periodic benefit cost	406	413	358
Additional amounts recognized	0	0	0
Total benefit cost	406	413	358
Additional Information [Abstract]
Minimum benefit obligation at year end	4,076	3,515	3,590
Increase (decrease) in minimum liability included in other comprehensive income (loss)	330	(313)	276
Assumptions used to determine benefit obligations [Abstract]
Discount rate used to determine net periodic benefit cost for years ended (in hundredths)	4.30%	3.20%	3.90%
Discount rate used to determine benefit obligations (in hundredths)	3.50%	4.30%	3.20%
Future salary increases (in hundredths)	4.00%	4.00%	4.00%
Expected future benefit payments [Abstract]
Benefit paid during fiscal year	176
2015	226
2016	281
2017	272
2018	272
2019	272
2020-2024	1,543
Salary Continuation Plan [Member] | Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined annual benefit plan amount	50
Salary Continuation Plan [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined annual benefit plan amount	125
Directors' Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Duration for benefit payment after retirement age	10 years
Retirement age	65 years
Reduced benefit age	55 years
Years of services for reduced benefit	10 years
Change in benefit obligation [Roll Forward]
Benefit obligation at beginning of year	715	743	701
Service cost	16	25	24
Interest cost	30	24	27
Plan loss (gain)	6	(62)	(1)
Benefits paid	(15)	(15)	(8)
Benefit obligation at end of year	752	715	743
Change in plan assets [Abstract]
Employer Contribution	15	15	8
Benefits paid	(15)	(15)	(8)
Fair value of plan assets at end of year	0	0	0
Reconciliation of funded status [Abstract]
Funded status	(752)	(715)	(743)
Unrecognized net plan loss	(67)	(75)	(12)
Net amount recognized	(819)	(790)	(755)
Amounts recognized in the consolidated balance sheets consist of [Abstract]
Accrued benefit liability	(752)	(715)	(743)
Accumulated other comprehensive income	(67)	(75)	(12)
Net amount recognized	(819)	(790)	(755)
Components of net periodic benefit cost [Abstract]
Service cost	16	25	24
Interest cost	30	24	27
Recognized actuarial (gain)loss	(2)	0	0
Net periodic benefit cost	44	49	51
Additional amounts recognized	0	0	0
Total benefit cost	44	49	51
Additional Information [Abstract]
Minimum benefit obligation at year end	752	715	743
Increase (decrease) in minimum liability included in other comprehensive income (loss)	8	(63)	(1)
Assumptions used to determine benefit obligations [Abstract]
Discount rate used to determine net periodic benefit cost for years ended (in hundredths)	4.10%	3.20%	3.80%
Discount rate used to determine benefit obligations (in hundredths)	4.00%	4.10%	3.20%
Expected future benefit payments [Abstract]
Benefit paid during fiscal year	15
2015	16
2016	30
2017	44
2018	55
2019	60
2020-2024	361
Directors' Retirement Plan [Member] | Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Directors' retirement benefit per year of service	1
Directors' Retirement Plan [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Directors' retirement benefit per year of service	15
Executive Deferral Plan [Member]
Expected future benefit payments [Abstract]
Single-premium payment on insurance purchased	1,125
Cash surrender value of life insurance	2,289	2,225
Increase in accrued liabilities	30	35
Expenses	30	35	45
Director Deferral Plan [Member]
Expected future benefit payments [Abstract]
Cash surrender value of life insurance	124	120
Increase in accrued liabilities	1	1
Expenses	$ 1	$ 1	$ 1