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v3.20.1

Regulatory Capital (Details) $ in Millions | Jan. 01, 2020 USD ($) | Mar. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Mar. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
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Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |
Income Tax Effects Allocated Directly to Equity, Cumulative Effect of Change in Accounting Principle | $ (24.1) |  |  |  |
Total risk-based capital: |  |  |  |  |
Actual, Amount |  | $ 1,460.3 | $ 1,495.3 |  |
Actual, Ratio |  | 0.1367 | 0.1410 |  |
Minimum Required for Capital Adequacy Purposes, Amount |  | $ 854.8 | $ 848.5 |  |
Minimum Required for Capital Adequacy Purposes, Ratio |  | 0.08000 | 0.0800 |  |
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Amount |  | $ 1,121.9 | $ 1,113.6 |  |
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Ratio |  | 10.50% | 10.50% |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount |  | $ 1,068.5 | $ 1,060.6 |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio |  | 0.1000 | 0.1000 |  |
Tier 1 risk-based capital: |  |  |  |  |
Actual, Amount |  | $ 1,367.7 | $ 1,422.3 |  |
Actual, Ratio |  | 0.1280 | 0.1341 |  |
Minimum Required for Capital Adequacy Purposes, Amount |  | $ 641.1 | $ 636.3 |  |
Minimum Required for Capital Adequacy Purposes, Ratio |  | 0.06000 | 0.0600 |  |
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Amount |  | $ 908.2 | $ 901.5 |  |
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Ratio |  | 8.50% | 8.50% |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount |  | $ 854.8 | $ 848.5 |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio |  | 0.0800 | 0.0800 |  |
Common equity tier 1 risk-based capital: |  |  |  |  |
Actual, Amount |  | $ 1,283.6 | $ 1,338.2 |  |
Actual, Ratio |  | 12.01% | 12.62% |  |
Minimum Required for Capital Adequacy Purposes, Amount |  | $ 480.8 | $ 477.3 |  |
Minimum Required for Capital Adequacy Purposes, Ratio |  | 4.50% | 4.50% |  |
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Amount |  | $ 747.9 | $ 742.4 |  |
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Ratio |  | 7.00% | 7.00% |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount |  | $ 694.5 | $ 689.4 |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio |  | 6.50% | 6.50% |  |
Leverage capital ratio: |  |  |  |  |
Actual, Amount |  | $ 1,367.7 | $ 1,422.3 |  |
Actual, Ratio |  | 0.0990 | 0.1013 |  |
Capital Adequacy Purposes and Conservation Buffer, Amount |  | $ 552.5 | $ 561.6 |  |
Capital Adequacy Purposes and Conservation Buffer, Ratio |  | 0.04000 | 0.0400 |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount |  | $ 690.6 | $ 702.0 |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio |  | 0.0500 | 0.0500 |  |
Accounts Receivable, Allowance for Credit Loss | 29.0 | $ 129.1 | $ 73.0 | $ 72.4 | $ 73.0
FIB |  |  |  |  |
Total risk-based capital: |  |  |  |  |
Actual, Amount |  | $ 1,339.7 | $ 1,321.4 |  |
Actual, Ratio |  | 0.1258 | 0.1250 |  |
Minimum Required for Capital Adequacy Purposes, Amount |  | $ 852.3 | $ 845.8 |  |
Minimum Required for Capital Adequacy Purposes, Ratio |  | 0.08000 | 0.0800 |  |
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Amount |  | $ 1,118.6 | $ 1,110.1 |  |
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Ratio |  | 10.50% | 10.50% |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount |  | $ 1,065.3 | $ 1,057.2 |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio |  | 0.1000 | 0.1000 |  |
Tier 1 risk-based capital: |  |  |  |  |
Actual, Amount |  | $ 1,247.1 | $ 1,248.4 |  |
Actual, Ratio |  | 0.1171 | 0.1181 |  |
Minimum Required for Capital Adequacy Purposes, Amount |  | $ 639.2 | $ 634.3 |  |
Minimum Required for Capital Adequacy Purposes, Ratio |  | 0.06000 | 0.0600 |  |
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Amount |  | $ 905.5 | $ 898.6 |  |
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Ratio |  | 8.50% | 8.50% |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount |  | $ 852.3 | $ 845.8 |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio |  | 0.0800 | 0.0800 |  |
Common equity tier 1 risk-based capital: |  |  |  |  |
Actual, Amount |  | $ 1,247.1 | $ 1,248.4 |  |
Actual, Ratio |  | 11.71% | 11.81% |  |
Minimum Required for Capital Adequacy Purposes, Amount |  | $ 479.4 | $ 475.7 |  |
Minimum Required for Capital Adequacy Purposes, Ratio |  | 4.50% | 4.50% |  |
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Amount |  | $ 745.7 | $ 740.0 |  |
For Capital Adequacy Purposes Plus Capital Conservation Buffer, Ratio |  | 7.00% | 7.00% |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount |  | $ 692.5 | $ 687.2 |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio |  | 6.50% | 6.50% |  |
Leverage capital ratio: |  |  |  |  |
Actual, Amount |  | $ 1,247.1 | $ 1,248.4 |  |
Actual, Ratio |  | 0.0905 | 0.0891 |  |
Capital Adequacy Purposes and Conservation Buffer, Amount |  | $ 551.2 | $ 560.4 |  |
Capital Adequacy Purposes and Conservation Buffer, Ratio |  | 0.0400 | 0.0400 |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Amount |  | $ 689.0 | $ 700.4 |  |
Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements, Ratio |  | 0.0500 | 0.0500 |  |
Retained Earnings [Member] |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |
Income Tax Effects Allocated Directly to Equity, Cumulative Effect of Change in Accounting Principle | (24.1) |  |  |  |
Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Leverage capital ratio: |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss | 30.0 |  | $ 30.0 |  |
Change in Accounting Principle, Indirect Effect [Member] |  |  |  |  |
Leverage capital ratio: |  |  |  |  |
Accounts Receivable, Allowance for Credit Loss | $ 6.5 |  |  |  |

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