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Stock Option And Stock Award Plans (Summary Of Additional Information On Non-Vested Restricted Stock Outstanding) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of Shares, Forfeited	82,214
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of Shares, Outstanding, Beginning Balance	285,935	244,736	206,676
Number of Shares, Granted	155,138	185,422	119,915
Number of Shares, Vested	(148,709)	(117,834)	(64,702)
Number of Shares, Forfeited	(57,385)	(26,389)	(17,153)
Number of Shares, Outstanding, Ending Balance	234,979	285,935	244,736
Wgtd. Ave. Grant Date Fair Value/Sh., Beginning Balance	$ 18.27	$ 16.20	$ 16.15
Wgtd. Ave. Grant Date Fair Value/Sh., Granted	14.55	18.46	17.39
Wgtd. Ave. Grant Date Fair Value/Sh., Vested	17.39	14.76	18.31
Wgtd. Ave. Grant Date Fair Value/Sh., Forfeited	17.00	16.11	15.84
Wgtd. Ave. Grant Date Fair Value/Sh., Ending Balance	$ 16.68	$ 18.27	$ 16.20
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Grant Date Fair Value, Outstanding, Beginning Balance	$ 5,224	$ 3,965	$ 3,337
Grant Date Fair Value, Granted	2,257	3,423	2,085
Grant Date Fair Value, Vested	(2,586)	(1,739)	(1,185)
Grant Date Fair Value, Forfeited	(976)	(425)	(272)
Grant Date Fair Value, Outstanding, Ending Balance	$ 3,919	$ 5,224	$ 3,965
Maximum Non Vested Restricted Stock Units Issuable Upon Satisfaction Of Certain Performance Criteria [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of Shares, Outstanding, Beginning Balance	147,663	184,709	172,133
Number of Shares, Granted	34,275	57,442	61,227
Number of Shares, Vested	(37,370)	(69,926)	0
Number of Shares, Forfeited	(32,066)	(24,562)	(48,651)
Number of Shares, Outstanding, Ending Balance	112,502	147,663	184,709
Wgtd. Ave. Grant Date Fair Value/Sh., Beginning Balance	$ 21.25	$ 16.97	$ 15.78
Wgtd. Ave. Grant Date Fair Value/Sh., Granted	15.25	18.34	17.35
Wgtd. Ave. Grant Date Fair Value/Sh., Vested	17.38	10.96	0
Wgtd. Ave. Grant Date Fair Value/Sh., Forfeited	17.36	11.51	13.23
Wgtd. Ave. Grant Date Fair Value/Sh., Ending Balance	$ 21.82	$ 21.25	$ 16.97
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Grant Date Fair Value, Outstanding, Beginning Balance	$ 3,138	$ 3,134	$ 2,716
Grant Date Fair Value, Granted	523	1,053	1,062
Grant Date Fair Value, Vested	(649)	(766)	0
Grant Date Fair Value, Forfeited	(557)	(283)	(644)
Grant Date Fair Value, Outstanding, Ending Balance	$ 2,455	$ 3,138	$ 3,134

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Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period Total Fair Value

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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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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