Share-Based Compensation Plans (Narrative) (Details)	6 Months Ended
Jun. 30, 2020 USD ($) Director $ / shares shares	Jun. 30, 2019 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense \| $	$ 0
Stock options awarded	0	0
Stock options activity \| $	$ 0
Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued in lieu of cash	5,403
Grant date fair value \| Director	4
Granted, Weighted Average Market Price at Grant Date \| $ / shares	$ 17.57
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense \| $	$ 3,000,000.0
Expected recognition expense period, weighted average period in years	2 years 2 months 12 days
PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares of common stock awarded	23,302
Granted, Weighted Average Market Price at Grant Date \| $ / shares	$ 25.63
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.
Non-employee Directors Stock Incentive Plan [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Required service period	1 year
Restricted shares of common stock awarded	12,798
Non-employee Directors Stock Incentive Plan [Member] \| Vested Immediately [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares of common stock awarded	6,399
Non-employee Directors Stock Incentive Plan [Member] \| Vested After Completion of One-Year Service Requirement [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares of common stock awarded	6,399

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

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-Publisher FASB
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-Topic 718
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-Section 50
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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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Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition.

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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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The weighted average fair value at grant date for nonvested equity-based awards issued 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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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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Gross number of share options (or share units) granted during the period.

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Percentage of vesting of award under share-based payment arrangement.

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Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

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