For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Commitments and Contingencies (Narrative) (Details) $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 30, 2021 branches	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Financial guarantees in connection with standby letters of credit		$ 0.0	$ 0.0
Standby letters of credit expiring within one year		100.3
Standby letters of credit expiring thereafter		11.5
Residential mortgage loan repurchase reserve liability		$ 1.0
Subsequent Event
Commitments and Contingencies Disclosure [Abstract]
Number Of Stores Consolidated \| branches	12
Subsequent Event [Line Items]
Number Of Stores Consolidated \| branches	12
Real Estate Loans As Part Of Loan Portfolio
Concentration Risk [Line Items]
Concentration risk (as a percent)		71.00%		71.00%