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Nature of Operations and Summary of Significant Accounting Policies (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) Segment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Interest-Bearing Time Deposits in Other Banks [Abstract]
Interest-bearing time deposits in other banks	$ 31,759	$ 30,168
Securities [Abstract]
Securities, available-for-sale	0	0
Securities, held to maturity	0	0
Long-Lived Asset Impairment [Abstract]
Asset impairment charges	$ 0	0	$ 0
Segments [Abstract]
Number of reportable segment \| Segment	1
Income Taxes Abstract]
Interest accrued and penalties related to unrecognized tax benefits	$ 0	$ 0	$ 0
Minimum [Member]
Interest-Bearing Time Deposits in Other Banks [Abstract]
Maturity period of interest bearing time deposits	1 year
Maximum [Member]
Interest-Bearing Time Deposits in Other Banks [Abstract]
Maturity period of interest bearing time deposits	5 years
Buildings and Improvements [Member] \| Minimum [Member]
Estimated Useful Lives of Premises and Equipment [Abstract]
Estimated useful life	15 years
Buildings and Improvements [Member] \| Maximum [Member]
Estimated Useful Lives of Premises and Equipment [Abstract]
Estimated useful life	30 years
Furniture and Equipment [Member] \| Minimum [Member]
Estimated Useful Lives of Premises and Equipment [Abstract]
Estimated useful life	5 years
Furniture and Equipment [Member] \| Maximum [Member]
Estimated Useful Lives of Premises and Equipment [Abstract]
Estimated useful life	10 years
Aircraft [Member] \| Minimum [Member]
Estimated Useful Lives of Premises and Equipment [Abstract]
Estimated useful life	5 years
Aircraft [Member] \| Maximum [Member]
Estimated Useful Lives of Premises and Equipment [Abstract]
Estimated useful life	7 years
Automobiles [Member] \| Minimum [Member]
Estimated Useful Lives of Premises and Equipment [Abstract]
Estimated useful life	3 years
Automobiles [Member] \| Maximum [Member]
Estimated Useful Lives of Premises and Equipment [Abstract]
Estimated useful life	5 years
Core Deposits [Member]
Goodwill and Intangible Assets [Abstract]
Estimated useful life	10 years