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v3.20.4

Shareholders' Equity (Details) $ / shares in Units, $ in Thousands | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Dec. 31, 2020 USD ($) $ / shares shares | Dec. 31, 2019 USD ($) $ / shares | Feb. 28, 2021 shares | Jan. 31, 2020 shares | Jan. 31, 2019 shares | Dec. 31, 2015 USD ($) | Oct. 08, 2015 USD ($)
Total risk-based capital: |  |  |  |  |  |  |
Actual Regulatory Capital - Amount | $ 498,290 | $ 455,702 |  |  |  |  |
Capital To Risk Weighted Assets | 0.1540 | 0.1444 |  |  |  |  |
Minimum Requirement for capital Adequacy Including Capital Buffer Total Risk-Based Capital Ratio | 10.50% |  |  |  |  |  |
Minimum Regulatory Capital Required - Ratio |  | 0.1050 |  |  |  |  |
Minimum Regulatory Provision To Be Well Capitalized - Ratio | 0.1000 | 0.1000 |  |  |  |  |
Tier 1 capital: |  |  |  |  |  |  |
Actual Regulatory Capital - Amount | $ 445,858 | $ 415,511 |  |  |  |  |
Actual Regulatory Capital - Ratio | 0.1378 | 0.1316 |  |  |  |  |
Minimum Requirement for capital Adequacy Including Capital Buffer Tier I Risk-Based Capital Ratio | 8.50% |  |  |  |  |  |
Minimum Regulatory Capital Required - Ratio |  | 0.0850 |  |  |  |  |
Minimum Regulatory Provision To Be Well Capitalized - Ratio | 0.0600 | 0.0600 |  |  |  |  |
Common equity tier I capital | $ 402,858 | $ 372,511 |  |  |  |  |
Tier 1 leverage capital ratio: |  |  |  |  |  |  |
Actual Regulatory Capital - Amount | $ 445,858 | $ 415,511 |  |  |  |  |
Actual Regulatory Capital - Ratio | 0.0913 | 0.0955 |  |  |  |  |
Minimum Regulatory Capital Required - Ratio | 0.0400 | 0.0400 |  |  |  |  |
Common Equity Tier I Risk Based Capital Ratio | 12.45% | 11.80% |  |  |  |  |
Minimum Requirement for capital Adequacy Including Capital Buffer Common Equity Tier I Risk-Based Capital Ratio | 7.00% |  |  |  |  |  |
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets |  | 7.00% |  |  |  |  |
Value Of Trust Preferred Securities Included In Tier 1 Capital | $ 43,000 | $ 43,000 |  |  |  | $ 43,000 |
Subordinated Debt | $ 59,331 | $ 59,080 |  |  |  | 15,000 | $ 15,000
Subordinated Debt, Phase-Out Period, Annual, Percentage | 0.20 |  |  |  |  |  |
Share Repurchase Program Three [Member] |  |  |  |  |  |  |
Tier 1 leverage capital ratio: |  |  |  |  |  |  |
Stock Repurchased During Period, Shares | shares | 488,052 |  |  |  |  |  |
Shares repurchased, average cost per share | $ / shares | $ 42.61 |  |  |  |  |  |
Stock repurchase program, shares of common stock approved for repurchase | shares |  |  |  |  | 775,000 |  |
Share Repurchase Program Four [Member] |  |  |  |  |  |  |
Tier 1 leverage capital ratio: |  |  |  |  |  |  |
Stock Repurchased During Period, Shares | shares | 274,354 |  |  |  |  |  |
Shares repurchased, average cost per share | $ / shares |  | $ 35.36 |  |  |  |  |
Stock repurchase program, shares of common stock approved for repurchase | shares |  |  |  | 750,000 |  |  |
Stock Repurchase Program, Period in Force |  | 12 months |  |  |  |  |
Share Repurchase Program Five |  |  |  |  |  |  |
Tier 1 leverage capital ratio: |  |  |  |  |  |  |
Stock Repurchase Program, Period in Force | 12 months |  |  |  |  |  |
Share Repurchase Program Five | Subsequent Event [Member] |  |  |  |  |  |  |
Tier 1 leverage capital ratio: |  |  |  |  |  |  |
Stock repurchase program, shares of common stock approved for repurchase | shares |  |  | 750,000 |  |  |  |
Subsidiaries [Member] |  |  |  |  |  |  |
Total risk-based capital: |  |  |  |  |  |  |
Actual Regulatory Capital - Amount | $ 460,611 | $ 423,540 |  |  |  |  |
Capital To Risk Weighted Assets | 0.1428 | 0.1345 |  |  |  |  |
Minimum Requirement for capital Adequacy Including Capital Buffer Total Risk-Based Capital Ratio | 10.50% |  |  |  |  |  |
Minimum Regulatory Capital Required - Ratio |  | 0.1050 |  |  |  |  |
Minimum Regulatory Provision To Be Well Capitalized - Ratio | 0.1000 | 0.1000 |  |  |  |  |
Tier 1 capital: |  |  |  |  |  |  |
Actual Regulatory Capital - Amount | $ 420,294 | $ 398,349 |  |  |  |  |
Actual Regulatory Capital - Ratio | 0.1303 | 0.1265 |  |  |  |  |
Minimum Requirement for capital Adequacy Including Capital Buffer Tier I Risk-Based Capital Ratio | 8.50% |  |  |  |  |  |
Minimum Regulatory Capital Required - Ratio |  | 0.0850 |  |  |  |  |
Minimum Regulatory Provision To Be Well Capitalized - Ratio | 0.0800 | 0.0800 |  |  |  |  |
Common equity tier I capital | $ 420,294 | $ 398,349 |  |  |  |  |
Tier 1 leverage capital ratio: |  |  |  |  |  |  |
Actual Regulatory Capital - Amount | $ 420,294 | $ 398,349 |  |  |  |  |
Actual Regulatory Capital - Ratio | 0.0864 | 0.0919 |  |  |  |  |
Minimum Regulatory Capital Required - Ratio | 0.0400 | 0.0400 |  |  |  |  |
Minimum Regulatory Provision To Be Well Capitalized - Ratio | 0.0500 | 0.0500 |  |  |  |  |
Common Equity Tier I Risk Based Capital Ratio | 13.03% | 12.65% |  |  |  |  |
Minimum Requirement for capital Adequacy Including Capital Buffer Common Equity Tier I Risk-Based Capital Ratio | 7.00% |  |  |  |  |  |
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets |  | 7.00% |  |  |  |  |
Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets | 6.50% | 6.50% |  |  |  |  |
Tier II Capital [Member] |  |  |  |  |  |  |
Tier 1 leverage capital ratio: |  |  |  |  |  |  |
Subordinated Debt | $ 12,000 | $ 15,000 |  |  |  | $ 15,000 |

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