Federal Income Taxes (Schedule of Income Tax Expense) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Federal Income Taxes [Abstract]
Current tax expense: Federal									$ 2,035	$ 3,121
Current tax expense: State									8	6
Deferred income tax (benefit) expense: Federal									247	2,329
Income tax expense	$ 643	$ 629	$ 436	$ 582	$ 2,682	$ 1,001	$ 746	$ 1,027	$ 2,290	$ 5,456