Stock-Based Compensation Plans (Summary of Activity Related to Share Based Awards) (Details) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($) $ / shares shares
Restricted Stock Units (RSUs) [Member]
Number of Shares
Nonvested, beginning \| shares	46,367
Granted \| shares	20,689
Vested \| shares	(12,818)
Forfeited \| shares	(4,653)
Nonvested, ending \| shares	49,585
Weighted Average Grant Date Fair Value
Nonvested, beginning \| $ / shares	$ 37.80
Granted \| $ / shares	48.05
Vested \| $ / shares	39.49
Forfeited \| $ / shares	42.10
Nonvested, ending \| $ / shares	$ 41.23
Weighted-Average Remaining Contractual Term (Years)
Nonvested, weighted average remaining contractual term	3 years 1 month 6 days
Aggregate Intrinsic Value
Nonvested, aggregate intrinsic value \| $	$ 2,388
Unrecognized Compensation
Nonvested, unrecognized compensation \| $	$ 1,529
Restricted Stock [Member]
Number of Shares
Nonvested, beginning \| shares	23,656
Granted \| shares	19,538
Vested \| shares	(21,706)
Forfeited \| shares	(2,517)
Nonvested, ending \| shares	18,971
Weighted Average Grant Date Fair Value
Nonvested, beginning \| $ / shares	$ 34.96
Granted \| $ / shares	47.29
Vested \| $ / shares	41.52
Forfeited \| $ / shares	37.64
Nonvested, ending \| $ / shares	$ 39.80
Weighted-Average Remaining Contractual Term (Years)
Nonvested, weighted average remaining contractual term	1 year 7 months 6 days
Aggregate Intrinsic Value
Nonvested, aggregate intrinsic value \| $	$ 914
Unrecognized Compensation
Nonvested, unrecognized compensation \| $	$ 459
Management Stock Purchase Plan [Member]
Number of Shares
Nonvested, beginning \| shares	17,024
Granted \| shares	9,619
Vested \| shares	(6,338)
Forfeited \| shares	(1,414)
Nonvested, ending \| shares	18,891
Weighted Average Grant Date Fair Value
Nonvested, beginning \| $ / shares	$ 8.74
Granted \| $ / shares	16.35
Vested \| $ / shares	11.02
Forfeited \| $ / shares	11.46
Nonvested, ending \| $ / shares	$ 11.64
Weighted-Average Remaining Contractual Term (Years)
Nonvested, weighted average remaining contractual term	8 months 12 days
Aggregate Intrinsic Value
Nonvested, aggregate intrinsic value \| $	$ 356
Unrecognized Compensation
Nonvested, unrecognized compensation \| $	$ 88
Performance Shares [Member]
Number of Shares
Nonvested, beginning \| shares	51,394
Granted \| shares	17,822
Vested \| shares	(10,157)
Forfeited \| shares	(7,479)
Nonvested, ending \| shares	51,580
Weighted Average Grant Date Fair Value
Nonvested, beginning \| $ / shares	$ 37.07
Granted \| $ / shares	46.95
Vested \| $ / shares	42.82
Forfeited \| $ / shares	38.32
Nonvested, ending \| $ / shares	$ 39.17
Weighted-Average Remaining Contractual Term (Years)
Nonvested, weighted average remaining contractual term	1 year 7 months 6 days
Aggregate Intrinsic Value
Nonvested, aggregate intrinsic value \| $	$ 2,020
Unrecognized Compensation
Nonvested, unrecognized compensation \| $	$ 434
DCRP Awards [Member]
Number of Shares
Nonvested, beginning \| shares	5,372
Granted \| shares	5,167
Vested \| shares	(2,933)
Forfeited \| shares	(600)
Nonvested, ending \| shares	7,006
Weighted Average Grant Date Fair Value
Nonvested, beginning \| $ / shares	$ 33.93
Granted \| $ / shares	47.75
Vested \| $ / shares	40.16
Forfeited \| $ / shares	47.75
Nonvested, ending \| $ / shares	$ 40.33
Weighted-Average Remaining Contractual Term (Years)
Nonvested, weighted average remaining contractual term	16 years
Aggregate Intrinsic Value
Nonvested, aggregate intrinsic value \| $	$ 337
Unrecognized Compensation
Nonvested, unrecognized compensation \| $	$ 234

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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