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Goodwill and Other Intangible Assets (Details Textuals) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
	Feb. 14, 2020	Mar. 31, 2020	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill, Impairment Loss		$ 0	$ 0
Goodwill [Line Items]
Goodwill		1,191,388	1,176,230
Other Intangibles
Goodwill [Line Items]
Finite-Lived Intangible Assets, Net		19,211	20,027
First Staunton Bancshares [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	$ 15,158
Insurance Operations [Member]
Goodwill [Line Items]
Goodwill		82,000
Insurance Operations [Member] \| Other Intangibles
Goodwill [Line Items]
Finite-Lived Intangible Assets, Net		$ 18,000	$ 18,000