Share-Based Compensation Plans (Narrative) (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) shares
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options awarded granted	0
Unrecognized compensation expense \| $	$ 3.8
Expected recognition expense period, weighted average period in years	2 years 4 months 24 days
PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options awarded granted	22,178
Management Stock Incentive Plan [Member] \| ROAE Return on Average Equity [Member] \| PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage upon achievement of targets	50.00%
Required service period	3 years
Share-based vesting description	The shares earned based on the achievement of the ROAE performance requirement, if any, will vest on the third anniversary of the grant date assuming the recipient’s continuous service to the Company.
Management Stock Incentive Plan [Member] \| ROAA Performance Requirement [Member] \| PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage upon achievement of targets	50.00%
Required service period	3 years
Share-based vesting description	The shares earned based on the achievement of the ROAA performance requirement, if any, will vest on the third anniversary of the grant date assuming the recipient’s continuous service to the Company.

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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