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Regulatory Capital (Details) - USD ($) $ in Millions | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Total risk-based capital: |  |
Actual, Amount | $ 1,460.2 | $ 1,285.0
Actual, Ratio | 13.71% | 12.99%
Minimum Required for Capital Adequacy Purposes, Amount | $ 851.9 | $ 791.2
Minimum Required for Capital Adequacy Purposes, Ratio | 8.00% | 8.00%
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Amount | $ 1,118.1 | $ 976.6
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Ratio | 10.50% | 9.875%
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount | $ 1,064.9 | $ 989.0
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio | 10.00% | 10.00%
Tier 1 risk-based capital: |  |
Actual, Amount | $ 1,385.2 | $ 1,212.0
Actual, Ratio | 13.01% | 12.26%
Minimum Required for Capital Adequacy Purposes, Amount | $ 638.9 | $ 593.4
Minimum Required for Capital Adequacy Purposes, Ratio | 6.00% | 6.00%
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Amount | $ 905.2 | $ 778.8
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Ratio | 8.50% | 7.875%
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount | $ 851.9 | $ 791.2
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio | 8.00% | 8.00%
Common equity tier 1 risk-based capital: |  |
Actual, Amount | $ 1,298.3 | $ 1,127.8
Actual, Ratio | 12.19% | 11.40%
Minimum Required for Capital Adequacy Purposes, Amount | $ 479.2 | $ 445.0
Minimum Required for Capital Adequacy Purposes, Ratio | 4.50% | 4.50%
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Amount | $ 745.4 | $ 630.5
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Ratio | 7.00% | 6.375%
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount | $ 692.2 | $ 642.8
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio | 6.50% | 6.50%
Leverage capital ratio: |  |
Actual, Amount | $ 1,385.2 | $ 1,212.0
Actual, Ratio | 9.96% | 9.47%
Capital Adequacy Purposes and Conservation Buffer, Amount | $ 556.2 | $ 511.9
Capital Adequacy Purposes and Conservation Buffer, Ratio | 4.00% | 4.00%
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount | $ 695.3 | $ 639.9
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio | 5.00% | 5.00%
FIB |  |
Total risk-based capital: |  |
Actual, Amount | $ 1,308.6 | $ 1,184.5
Actual, Ratio | 12.33% | 12.01%
Minimum Required for Capital Adequacy Purposes, Amount | $ 849.0 | $ 788.8
Minimum Required for Capital Adequacy Purposes, Ratio | 8.00% | 8.00%
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Amount | $ 1,114.3 | $ 973.7
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Ratio | 10.50% | 9.875%
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount | $ 1,061.3 | $ 986.0
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio | 10.00% | 10.00%
Tier 1 risk-based capital: |  |
Actual, Amount | $ 1,233.7 | $ 1,111.6
Actual, Ratio | 11.62% | 11.27%
Minimum Required for Capital Adequacy Purposes, Amount | $ 636.8 | $ 591.6
Minimum Required for Capital Adequacy Purposes, Ratio | 6.00% | 6.00%
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Amount | $ 902.1 | $ 776.5
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Ratio | 8.50% | 7.875%
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount | $ 849.0 | $ 788.8
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio | 8.00% | 8.00%
Common equity tier 1 risk-based capital: |  |
Actual, Amount | $ 1,233.7 | $ 1,111.6
Actual, Ratio | 11.62% | 11.27%
Minimum Required for Capital Adequacy Purposes, Amount | $ 477.6 | $ 443.7
Minimum Required for Capital Adequacy Purposes, Ratio | 4.50% | 4.50%
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Amount | $ 742.9 | $ 628.6
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Ratio | 7.00% | 6.375%
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount | $ 689.8 | $ 640.9
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio | 6.50% | 6.50%
Leverage capital ratio: |  |
Actual, Amount | $ 1,233.7 | $ 1,111.6
Actual, Ratio | 8.96% | 8.97%
Capital Adequacy Purposes and Conservation Buffer, Amount | $ 550.5 | $ 495.9
Capital Adequacy Purposes and Conservation Buffer, Ratio | 4.00% | 4.00%
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount | $ 688.1 | $ 619.8
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio | 5.00% | 5.00%

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- Definition The amount of Tier 1 Leverage Capital required to be categorized as well 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 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826 + Details
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- Definition The amount of Tier 1 Risk Based Capital required to be categorized as well 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 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826 + Details
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- Definition 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. + 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 + Details
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