Regulatory Matters (Actual And Required Capital Ratios) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Parent Company [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage, Actual Amount	$ 322,680	$ 265,246
Tier 1 leverage, Actual Ratio	8.13%	7.36%
Tier 1 leverage, Well Capitalized, Amount	$ 198,387	$ 180,119
Tier 1 leverage, Well Capitalized, Ratio	5.00%	5.00%
CET1 capital, Actual Amount	$ 305,351	$ 247,906
CET1 capital, Actual Ratio	10.16%	9.59%
CET1 capital, Well Capitalized, Amount	$ 195,368	$ 167,970
CET1 capital, Well Capitalized, Ratio	6.50%	6.50%
Tier 1 capital, Actual Amount	$ 322,680	$ 265,246
Tier 1 capital, Actual Ratio	10.74%	10.26%
Tier 1 capital, Well Capitalized, Amount	$ 240,452	$ 206,733
Tier 1 capital, Well Capitalized, Ratio	8.00%	8.00%
Total risk-based capital, Actual Amount	$ 396,483	$ 335,241
Total risk-based capital, Actual Ratio	13.19%	12.97%
Total risk-based capital, Well Capitalized, Amount	$ 300,565	$ 258,416
Total risk-based capital, Well Capitalized, Ratio	10.00%	10.00%
Parent Company [Member] \| Phase-in Schedule [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage, For Capital Adequacy Purposes, Amount	$ 158,710	$ 144,095
Tier 1 leverage, For Capital Adequacy Purposes, Ratio	4.00%	4.00%
CET1 capital, For Capital Adequacy Purposes, Amount	$ 172,825	$ 132,438
CET1 capital, For Capital Adequacy Purposes, Ratio	5.75%	5.13%
Tier 1 capital, For Capital Adequacy Purposes, Amount	$ 217,910	$ 171,201
Tier 1 capital, For Capital Adequacy Purposes, Ratio	7.25%	6.63%
Total risk-based capital, For Capital Adequacy Purposes, Amount	$ 278,023	$ 222,884
Total risk-based capital, For Capital Adequacy Purposes, Ratio	9.25%	8.63%
Parent Company [Member] \| Fully Phased-in [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage, For Capital Adequacy Purposes, Amount	$ 158,710	$ 144,095
Tier 1 leverage, For Capital Adequacy Purposes, Ratio	4.00%	4.00%
CET1 capital, For Capital Adequacy Purposes, Amount	$ 210,396	$ 180,891
CET1 capital, For Capital Adequacy Purposes, Ratio	7.00%	7.00%
Tier 1 capital, For Capital Adequacy Purposes, Amount	$ 255,481	$ 219,654
Tier 1 capital, For Capital Adequacy Purposes, Ratio	8.50%	8.50%
Total risk-based capital, For Capital Adequacy Purposes, Amount	$ 315,594	$ 271,337
Total risk-based capital, For Capital Adequacy Purposes, Ratio	10.50%	10.50%
Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage, Actual Amount	$ 346,532	$ 284,765
Tier 1 leverage, Actual Ratio	8.75%	7.92%
Tier 1 leverage, Well Capitalized, Amount	$ 197,965	$ 179,828
Tier 1 leverage, Well Capitalized, Ratio	5.00%	5.00%
CET1 capital, Actual Amount	$ 346,532	$ 284,765
CET1 capital, Actual Ratio	11.57%	11.06%
CET1 capital, Well Capitalized, Amount	$ 194,688	$ 167,432
CET1 capital, Well Capitalized, Ratio	6.50%	6.50%
Tier 1 capital, Actual Amount	$ 346,532	$ 284,765
Tier 1 capital, Actual Ratio	11.57%	11.06%
Tier 1 capital, Well Capitalized, Amount	$ 239,616	$ 206,070
Tier 1 capital, Well Capitalized, Ratio	8.00%	8.00%
Total risk-based capital, Actual Amount	$ 381,204	$ 315,699
Total risk-based capital, Actual Ratio	12.73%	12.26%
Total risk-based capital, Well Capitalized, Amount	$ 299,520	$ 257,588
Total risk-based capital, Well Capitalized, Ratio	10.00%	10.00%
Bank [Member] \| Phase-in Schedule [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage, For Capital Adequacy Purposes, Amount	$ 158,372	$ 143,862
Tier 1 leverage, For Capital Adequacy Purposes, Ratio	4.00%	4.00%
CET1 capital, For Capital Adequacy Purposes, Amount	$ 172,224	$ 132,014
CET1 capital, For Capital Adequacy Purposes, Ratio	5.75%	5.13%
Tier 1 capital, For Capital Adequacy Purposes, Amount	$ 217,152	$ 170,652
Tier 1 capital, For Capital Adequacy Purposes, Ratio	7.25%	6.63%
Total risk-based capital, For Capital Adequacy Purposes, Amount	$ 277,056	$ 222,170
Total risk-based capital, For Capital Adequacy Purposes, Ratio	9.25%	8.63%
Bank [Member] \| Fully Phased-in [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage, For Capital Adequacy Purposes, Amount	$ 158,372	$ 143,862
Tier 1 leverage, For Capital Adequacy Purposes, Ratio	4.00%	4.00%
CET1 capital, For Capital Adequacy Purposes, Amount	$ 209,664	$ 180,312
CET1 capital, For Capital Adequacy Purposes, Ratio	7.00%	7.00%
Tier 1 capital, For Capital Adequacy Purposes, Amount	$ 254,592	$ 218,950
Tier 1 capital, For Capital Adequacy Purposes, Ratio	8.50%	8.50%
Total risk-based capital, For Capital Adequacy Purposes, Amount	$ 314,496	$ 270,467
Total risk-based capital, For Capital Adequacy Purposes, Ratio	10.50%	10.50%

Tangible Capital Required to be Well Capitalized

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Tangible Capital Required to be Well Capitalized, to Tangible Assets

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The amount of total capital as defined in the regulations.

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-Publisher FASB
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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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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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Tangible capital as defined in the regulations (generally includes outstanding stock plus retained earnings) for banking institutions subject to Office of Thrift Supervision (OTS) capital requirements.

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The minimum amount of tangible capital required under the regulatory framework for prompt corrective action.

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The minimum amount of Tangible Capital divided by tangible assets (Tangible Capital Ratio) as defined in the regulations.

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Tangible Capital divided by Tangible assets as defined in the regulations.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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