Postretirement Benefit Plans (Narrative) (Details) - USD ($)		12 Months Ended
	Jan. 01, 2008	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Settlement gains recognized		$ 3,000	$ 34,000
Postretirement Life Insurance [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, minimum service period requirement		20 years			10 years
Defined benefit plan, minimum retirement age		55 years
Defined benefit plan, benefit description, until age 65		The insurance amount will be $50,000 until age 65.
Life insurance coverage amount until age 65		$ 50,000
Defined benefit plan, benefit description, after age 65		After age 65, the insurance amount will decrease by $5,000 per year until age 74.
Decrease in coverage amount after age 65		$ 5,000
Life insurance coverage amount		$ 5,000
Defined Benefit Postretirement Health and Life Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, minimum service period requirement	10 years	20 years
Defined benefit plan, minimum retirement age		55 years
Percentage increase in postretirement benefit health insurance reimbursable premium		36.79%
Defined benefit plan, coverage period		5 years
Defined Benefit Postretirement Health and Life Benefit Plan [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Postretirement benefit health insurance reimbursable premium		$ 5,000
Post-Retirement Health Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, minimum service period requirement		20 years
Defined benefit plan, coverage period		5 years
Defined benefit plan, minimum retirement age		Employees who had achieved ten years of service as of January 1, 2008 and subsequently retire after at least 20 years of service are eligible for reimbursement of major medical insurance premiums up to $5,000, if the employee has not yet reached age 65.
Post-Retirement Health Benefit Plan [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Postretirement benefit health insurance reimbursable premium		$ 5,000
Defined Benefit Postretirement Health And Life Coverage [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, accumulated benefit obligation		342,000	404,000
Defined benefit plan, amount to be amortized from accumulated other comprehensive income (loss) next fiscal year		25,000
Director's Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, accumulated benefit obligation		1,142,000	1,077,000
Defined benefit plan, amount to be amortized from accumulated other comprehensive income (loss) next fiscal year		0
Unrecognized prior service cost credit generated by adoption of plan					$ 274,000
Recognized prior service cost credit and fully amortized				$ 22,000
Cash surrender value of bank owned life insurance		3,987,000	3,921,000
Scottdale Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, accumulated benefit obligation		5,401,000	5,587,000
Settlement gains recognized		(85,000)	(91,000)
Scottdale Defined Benefit Pension Plan [Member] | Scottdale Bank and Trust Company [Member] | Other Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Settlement gains recognized		$ 3,000	$ 34,000
Scottdale Defined Benefit Pension Plan [Member] | Maximum [Member] | Scottdale Bank and Trust Company [Member] | Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of target portfolio allocation		20.00%
Scottdale Defined Benefit Pension Plan [Member] | Maximum [Member] | Scottdale Bank and Trust Company [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of target portfolio allocation		50.00%
Scottdale Defined Benefit Pension Plan [Member] | Maximum [Member] | Scottdale Bank and Trust Company [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of target portfolio allocation		60.00%
Scottdale Defined Benefit Pension Plan [Member] | Minimum [Member] | Scottdale Bank and Trust Company [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of target portfolio allocation		30.00%
Scottdale Defined Benefit Pension Plan [Member] | Minimum [Member] | Scottdale Bank and Trust Company [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of target portfolio allocation		40.00%