Number of non employee directors.

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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 estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Gross number of share options (or share units) granted during the period.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of 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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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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Share-Based Compensation (Narrative) (Details) $ / shares in Units, $ in Thousands			12 Months Ended
	May 22, 2019	Feb. 26, 2019	Dec. 31, 2021 USD ($) Director $ / shares shares	Dec. 31, 2020 Director $ / shares shares	Dec. 31, 2019 Director $ / shares shares	Jun. 30, 2021 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period			10 years
Stock options awarded			0	0	0
Unrecognized compensation expense \| $			$ 0
Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value \| $ / shares			$ 32.03	$ 19.54	$ 29.78
Shares issued in lieu of cash			5,972	8,439	4,192
Number of non-employee directors \| Director			7	4	3
TSR Performance Requirement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	2 years 7 months 9 days	2 years 10 months 2 days
Risk free interest rate	2.18%	2.43%
Expected dividend yield	3.60%	3.20%
Expected stock price volatility	22.00%	21.30%
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense \| $			$ 2,400
Expected recognition expense period, weighted average period in years			1 year 9 months 18 days
Restricted Stock Awards [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares of common stock awarded					8,226
2015 Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant			816,000			734,000
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	1 year
Restricted shares of common stock awarded			9,350	12,798
Grant date fair value \| $ / shares			$ 0.06	$ 17.57	$ 27.33
Non-employee Directors Stock Incentive Plan [Member] \| Restricted Stock Awards [Member] \| Vested Immediately [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation, vesting percentage			50.00%
Restricted shares of common stock awarded			4,670	6,399	4,113
Non-employee Directors Stock Incentive Plan [Member] \| Restricted Stock Awards [Member] \| Vested After Completion of One-Year Service Requirement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation, vesting percentage			50.00%
Restricted shares of common stock awarded			4,680	6,399	4,113
Management Stock Incentive Plan [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Required service period			3 years	3 years	3 years
Grant date fair value \| $ / shares			$ 27.55	$ 25.02	$ 25.60
Share-based vesting date					Feb. 26, 2022
Management Stock Incentive Plan [Member] \| Restricted Stock Awards [Member] \| TSR Performance Requirement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Required service period			3 years
Management Stock Incentive Plan [Member] \| PSUs [Member] \| ROAE Return on Average Equity [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation, vesting percentage			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] \| PSUs [Member] \| ROAA Performance Requirement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation, vesting percentage			50.00%		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. If earned at target level, members of management will receive up to 22,178 shares of our common stock in the aggregate.
Management Stock Incentive Plan [Member] \| PSUs [Member] \| TSR Performance Requirement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation, vesting percentage					50.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			5 years
Maximum [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			3 years
Maximum [Member] \| 2015 Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of grants authorized			438,076
Maximum [Member] \| Management Stock Incentive Plan [Member] \| Restricted Stock Awards [Member] \| ROAA Performance Requirement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares of common stock awarded			22,178
Maximum [Member] \| Management Stock Incentive Plan [Member] \| Restricted Stock Awards [Member] \| Vested After Completion of Three-Year Service Requirement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares of common stock awarded			63,998	58,806	54,476
Maximum [Member] \| Management Stock Incentive Plan [Member] \| Restricted Stock Awards [Member] \| TSR Performance Requirement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares of common stock awarded			23,302		21,970
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			3 years
Minimum [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			2 years