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Concentrations of Credit Risk (Details) - Credit concentration risk - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
U.S. Government, its agencies and Government Sponsored Enterprises (GSEs)
Concentration Risk [Line Items]
Concentration risk amount	$ 389.1	$ 497.4
Concentration risk percentage	78.00%	87.00%
Non-Government Sponsored Enterprises
Concentration Risk [Line Items]
Concentration risk percentage	3.00%	1.00%
Loans portfolio
Concentration Risk [Line Items]
Concentration risk, threshold for major borrower, percentage	3.00%
Loans on real estate
Concentration Risk [Line Items]
Concentration risk percentage	76.00%	83.00%

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- Definition

Concentration Risk, Percentage, Threshold For Major Borrower

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Maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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.

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