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Stockholders' Equity and Regulatory Capital (Regulatory Capital Ratios) (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
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Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total Capital | $ 228,325 | $ 214,501
Total Capital to Risk-Weighted Assets |  | 11.98%
Total Capital, Minimum Required for Capital Adequacy Purposes |  | $ 143,219
Total Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes |  | 8.00%
Capital Required for Capital Adequacy Plus Capital Conservation Buffer |  | $ 165,597
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets |  | 9.25%
Tier 1 capital | 181,175 | $ 169,176
Tier 1 Capital to Risk-Weighted Assets |  | 9.45%
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes |  | $ 107,414
Tier 1 Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes |  | 6.00%
Tier One Risk Based Capital Required for Capital Adequacy Plus Capital Conservation Buffer |  | $ 129,792
Tier One Risk Based Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets |  | 7.25%
Common Equity Tier One Capital |  | $ 159,157
Common Equity Tier One Capital to Risk-Weighted Assets |  | 8.89%
Common Equity Tier One Capital Required for Capital Adequacy |  | $ 80,561
Common Equity Tier One Capital Required for Capital Adequacy to Risk-Weighted Assets |  | 4.50%
Common Equity Tier One Capital Required for Capital Adequacy Plus Capital Conservation Buffer |  | $ 102,939
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets |  | 5.75%
Tier 1 Capital |  | $ 169,176
Tier 1 Capital to Average Assets |  | 9.54%
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes |  | $ 70,920
Tier 1 Leverage Capital to Average Assets, Minimum Required for Capital Adequacy Purposes |  | 4.00%
Tier One Leverage Capital Required for Capital Adequacy Plus Capital Conservation Buffer |  | $ 70,920
Tier One Leverage Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets |  | 4.00%
Total capital (to risk-weighted assets) |  |
Compliance with Regulatory Capital Requirements under Banking Regulations |  |
Total Capital | $ 220,474 | $ 207,986
Total Capital to Risk-Weighted Assets | 11.49% | 11.66%
Total Capital, Minimum Required for Capital Adequacy Purposes | $ 153,456 | $ 142,736
Total Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes | 8.00% | 8.00%
Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 189,422 | $ 165,038
Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 9.875% | 9.25%
Total Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 191,820 | $ 178,420
Total Capital to Risk-Weighted Assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 10.00% | 10.00%
Tier 1 capital | $ 197,093 | $ 186,374
Tier 1 Capital to Risk-Weighted Assets | 10.27% | 10.45%
Tier 1 Capital, Minimum Required for Capital Adequacy Purposes | $ 115,092 | $ 107,052
Tier 1 Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes | 6.00% | 6.00%
Tier One Risk Based Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 151,058 | $ 129,354
Tier One Risk Based Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 7.88% | 7.25%
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 153,456 | $ 142,736
Tier 1 Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 8.00% | 8.00%
Common Equity Tier One Capital | $ 197,093 | $ 186,374
Common Equity Tier One Capital to Risk-Weighted Assets | 10.27% | 10.45%
Common Equity Tier One Capital Required for Capital Adequacy | $ 86,319 | $ 80,289
Common Equity Tier One Capital Required for Capital Adequacy to Risk-Weighted Assets | 4.50% | 4.50%
Common Equity Tier One Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 122,285 | $ 102,591
Common Equity Tier One Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 6.375% | 5.75%
Common Equity Tier One Capital to be Well Capitalized | $ 124,683 | $ 115,973
Common Equity Tier One Capital Required to be Well Capitalized to Risk-Weighted Assets | 6.50% | 6.50%
Tier 1 Capital | $ 197,093 | $ 186,374
Tier 1 Capital to Average Assets | 10.20% | 10.56%
Tier 1 Leverage Capital, Minimum Required for Capital Adequacy Purposes | $ 77,301 | $ 70,617
Tier 1 Leverage Capital to Average Assets, Minimum Required for Capital Adequacy Purposes | 4.00% | 4.00%
Tier One Leverage Capital Required for Capital Adequacy Plus Capital Conservation Buffer | $ 77,301 | $ 70,617
Tier One Leverage Capital Required for Capital Adequacy Plus Conservation Buffer to Risk Weighted Assets | 4.00% | 4.00%
Tier 1 Leverage Capital, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | $ 96,626 | $ 88,272
Tier 1 Leverage Capital to Average Assets, Minimum Required to be Well Capitalized Under Prompt Corrective Action Requirements | 5.00% | 5.00%

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