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Note 22 - Regulatory Matters - Capital and Leverage Ratios (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
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Common Equity Tier 1 to Risk-Weighted Assets, Actual amount | $ 1,959,832 | $ 1,904,820
Common Equity Tier 1 to Risk-Weighted Assets, Actual ratio | 12.97% | 13.66%
Common Equity Tier 1 to Risk-Weighted Assets, Minimum Capital Required | $ 1,057,880 | $ 889,287
Common Equity Tier 1 to Risk-Weighted Assets, Minimum Capital Required, Ratio | 7.00% | 6.375%
Common Equity Tier 1 to Risk-Weighted Assets, Required to be Considered Well Capitalized | $ 982,318 | $ 906,724
Common Equity Tier 1 to Risk-Weighted Assets, Required to be Considered Well Capitalized, Ratio | 6.50% | 6.50%
Tier 1 Capital to Risk-Weighted Assets, Actual amount | $ 1,959,832 | $ 1,904,820
Tier 1 Capital to Risk-Weighted Assets, Actual ratio | 12.97% | 13.66%
Tier 1 Capital to Risk-Weighted Assets, Minimum Capital Required | $ 1,284,569 | $ 1,098,531
Tier 1 Capital to Risk-Weighted Assets, Minimum Capital Required, Ratio | 8.50% | 7.875%
Tier 1 Capital to Risk-Weighted Assets, Required to be Considered Well Capitalized | $ 1,209,006 | $ 1,115,968
Tier 1 Capital to Risk-Weighted Assets, Required to be Considered Well Capitalized, Ratio | 8.00% | 8.00%
Total Capital to Risk-Weighted Assets, Actual amount | $ 2,086,911 | $ 2,029,462
Total Capital to Risk-Weighted Assets, Actual ratio | 13.81% | 14.55%
Total Capital to Risk-Weighted Assets, Minimum Capital Required | $ 1,586,821 | $ 1,377,523
Total Capital to Risk-Weighted Assets, Minimum Capital Required, Ratio | 10.50% | 9.875%
Total Capital to Risk-Weighted Assets, Required to be Considered Well Capitalized | $ 1,511,258 | $ 1,394,961
Total Capital to Risk-Weighted Assets, Required to be Considered Well Capitalized, Ratio | 10.00% | 10.00%
Leverage Ratio, Actual amount | $ 1,959,832 | $ 1,904,820
Leverage Ratio, Actual ratio | 11.23% | 11.89%
Leverage Ratio, Minimum Capital Required | $ 697,976 | $ 640,807
Leverage Ratio Minimum Capital Required, Ratio | 4.00% | 4.00%
Leverage Ratio, Required to be Considered Well Capitalized | $ 872,470 | $ 800,983
Leverage Ratio Required to be Considered Well Capitalized, Ratio | 5.00% | 5.00%
Bank [Member] |  |
Common Equity Tier 1 to Risk-Weighted Assets, Actual amount | $ 1,892,321 | $ 1,736,854
Common Equity Tier 1 to Risk-Weighted Assets, Actual ratio | 12.51% | 12.43%
Common Equity Tier 1 to Risk-Weighted Assets, Minimum Capital Required | $ 1,059,259 | $ 890,524
Common Equity Tier 1 to Risk-Weighted Assets, Minimum Capital Required, Ratio | 7.00% | 6.375%
Common Equity Tier 1 to Risk-Weighted Assets, Required to be Considered Well Capitalized | $ 983,597 | $ 907,985
Common Equity Tier 1 to Risk-Weighted Assets, Required to be Considered Well Capitalized, Ratio | 6.50% | 6.50%
Tier 1 Capital to Risk-Weighted Assets, Actual amount | $ 1,892,321 | $ 1,736,854
Tier 1 Capital to Risk-Weighted Assets, Actual ratio | 12.51% | 12.43%
Tier 1 Capital to Risk-Weighted Assets, Minimum Capital Required | $ 1,286,243 | $ 1,100,059
Tier 1 Capital to Risk-Weighted Assets, Minimum Capital Required, Ratio | 8.50% | 7.875%
Tier 1 Capital to Risk-Weighted Assets, Required to be Considered Well Capitalized | $ 1,210,581 | $ 1,117,520
Tier 1 Capital to Risk-Weighted Assets, Required to be Considered Well Capitalized, Ratio | 8.00% | 8.00%
Total Capital to Risk-Weighted Assets, Actual amount | $ 2,134,900 | $ 1,976,995
Total Capital to Risk-Weighted Assets, Actual ratio | 14.11% | 14.15%
Total Capital to Risk-Weighted Assets, Minimum Capital Required | $ 1,588,888 | $ 1,379,439
Total Capital to Risk-Weighted Assets, Minimum Capital Required, Ratio | 10.50% | 9.875%
Total Capital to Risk-Weighted Assets, Required to be Considered Well Capitalized | $ 1,513,227 | $ 1,396,900
Total Capital to Risk-Weighted Assets, Required to be Considered Well Capitalized, Ratio | 10.00% | 10.00%
Leverage Ratio, Actual amount | $ 1,892,321 | $ 1,736,854
Leverage Ratio, Actual ratio | 10.83% | 10.83%
Leverage Ratio, Minimum Capital Required | $ 699,173 | $ 641,755
Leverage Ratio Minimum Capital Required, Ratio | 4.00% | 4.00%
Leverage Ratio, Required to be Considered Well Capitalized | $ 873,966 | $ 802,146
Leverage Ratio Required to be Considered Well Capitalized, Ratio | 5.00% | 5.00%

X
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- Definition The minimum Common Equity Tier One Capital Ratio (Common Equity Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References No definition available. + Details
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- Definition The Common Equity Tier 1 capital ratio (Common EquityTier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action. + References No definition available. + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=117337116&loc=d3e65071-112826 + Details
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- Definition The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=117337116&loc=d3e65071-112826 + Details
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