Employee Benefit Plans (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2007	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Stock-based compensation expense		$ 128,000	$ 113,000
Weighted average exercise price		$ 17.78	$ 17.78		$ 17.76
Cash received from option exercises		$ 364,000
Employer's safe harbor contribution rate		3.00%
Employer's safe harbor contribution payable		$ 249,000
Prior year contribution payable credited in current year			$ 250,000
Defined contribution plan, cost recognized		247,000	248,000
Employer's matching contribution		214,000	212,000
Deferred compensation liability		1,584,000	1,603,000
Deferred compensation, compensation expense		20,000	42,000
Salary continuation liability		1,194,000	1,209,000
Salary continuation period expense		94,000	57,000
Supplemental Employee Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Present value of future plan liability		135,000	166,000
Supplemental retirement plans, cost recognized during period		$ 11,000	$ 16,000
Employee Stock Option [Member]
Defined Benefit Plan Disclosure [Line Items]
Shares authorized under share-based payment awards		300,000	161,090
Restricted Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Number of shares awarded		9,530	7,500
Award vesting period		3 years
Unrecognized compensation cost related to non-vested awards		$ 178,000
Employee Stock Purchase Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Shares authorized under share-based payment awards		250,000
Stock options awarded		0
Award expiration period		10 years
Award expiration date		Feb. 17, 2025
Number of share per year in addition to prior unissued shares		5,000
Shares issued during period under employee stock purchase plans		4,459	1,880
Shares reserved for future issuance		166,620
Employee Stock Purchase Plan [Member] | Employee Stock Option [Member]
Defined Benefit Plan Disclosure [Line Items]
Exercise price, lower range limit		$ 17.65
Exercise price, upper range limit		18.00
Weighted average exercise price		$ 17.78
Weighted average remaining contractual life		2 years 9 months 10 days
Compensation costs not yet recognized		$ 0
JVB Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of vested benefit				100.00%
Defined benefit plan, pre-tax settlement charge	$ 1,221,000
Excess funds transferred to 401(k) plan			$ 431,000
Maximum [Member] | Employee Stock Option [Member]
Defined Benefit Plan Disclosure [Line Items]
Award vesting period		5 years
Maximum [Member] | Employee Stock Purchase Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Option price as a percentage of fair value		100.00%
Minimum [Member] | Employee Stock Purchase Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Award vesting period		3 years
Option price as a percentage of fair value		95.00%