Employee Benefit Plans (Narrative) (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($)
BancShares Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 0.0

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration