Nature of Banking Activities and Significant Accounting Policies (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 20, 2018
Property, Plant and Equipment [Line Items]
Ownership percentage in subsidiaries	100.00%
Period interest on mortgage loans is discontinued	120 days
Period Interest on commercial loans discontinued	90 days
Credit card loans and other personal loans are charged off	180 days
Limit of the estimated appraised value of the furnished home	80.00%
Authorized issuance of shares of common stock	500,000
"More likely than not" threshold	50.00%
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0
Number of shares of common stock able to be repurchased				150,000
Treasury Stock, Shares, Retired	39,333	52,936	89,607
Stock Repurchased and Retired During Period, Value	$ 32.06	$ 29.54	$ 23.92
Maximum numbers of shares that may yet be purchased under plan	115,667
Building [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	39 years
Building [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	10 years
Furniture and equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	10 years
Furniture and equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years