| **Variable Interest Entities (New Markets Tax Credit Entities) (Details) - Primary Beneficiary - USD ($) $ in Millions** |        |         |        | 12 Months Ended |         |
|--------------------------------------------------------------------------------------------------------------------------|--------|---------|--------|-----------------|---------|
||
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Tax credit percentage                                                                                                    |   |    |   | 39.00%          |    |
| Restricted cash                                                                                                          |   |    |   | $ 0.9           | $ 1.1   |
| Percentage of recapture                                                                                                  |   |    |   | 100.00%         |    |
| Recapture period                                                                                                         |   |    |   | 7 years         |    |
| Assets                                                                                                                   |   |    |   | $ 140.9         | 140.9   |
| Liabilities                                                                                                              |   |    |   | $ 104.2         | $ 104.2 |
| NMTC 1                                                                                                                   |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Financial support                                                                                                        |   |    | $ 58.3 |            |    |
| Interest rate percent on financial support                                                                               |   |    | 1.00%  |            |    |
| NMTC 1 | Minimum                                                                                                         |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Interest rate percent on financial support                                                                               |   |    | 1.00%  |            |    |
| NMTC 1 | Maximum                                                                                                         |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Interest rate percent on financial support                                                                               |   |    | 3.96%  |            |    |
| NMTC 2                                                                                                                   |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Financial support                                                                                                        |   | $ 37.7  |   |            |    |
| Interest rate percent on financial support                                                                               |   | 1.00%   |   |            |    |
| NMTC 2 | Minimum                                                                                                         |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Interest rate percent on financial support                                                                               |   | 0.7099% |   |            |    |
| NMTC 2 | Maximum                                                                                                         |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Interest rate percent on financial support                                                                               |   | 0.7693% |   |            |    |
| NMTC 3                                                                                                                   |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Financial support                                                                                                        | $ 8.2  |    |   |            |    |
| Interest rate percent on financial support                                                                               | 1.00%  |    |   |            |    |
| NMTC 3 | Maximum                                                                                                         |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Interest rate percent on financial support                                                                               | 1.35%  |    |   |            |    |
| US Bancorp [Member] | NMTC 1                                                                                             |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Financial support to other entity                                                                                        |   |    | $ 22.4 |            |    |
| US Bancorp [Member] | NMTC 2                                                                                             |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Financial support to other entity                                                                                        |   | $ 17.5  |   |            |    |
| US Bancorp [Member] | NMTC 3                                                                                             |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Financial support to other entity                                                                                        | $ 3.8  |    |   |            |    |
| CDE's | NMTC 1                                                                                                           |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Financial support to other entity                                                                                        |   |    | $ 76.8 |            |    |
| CDE's | NMTC 2                                                                                                           |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Financial support to other entity                                                                                        |   | $ 55.2  |   |            |    |
| CDE's | NMTC 3                                                                                                           |   |    |   |            |    |
| **Variable Interest Entity [Line Items]**                                                                                |   |    |   |            |    |
| Financial support to other entity                                                                                        | $ 12.0 |    |   |            |    |

| X                                                                                                                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Investment Tax Credit Percent
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Variable Interest Entity, Financial or Other Support, Amount To Other Entity
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Variable Interest Entity, Financial or Other Support, Interest Rate Percentage
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Variable Interest Entity, Percentage of Recapture
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Variable Interest Entity, Recapture Period
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5710-111685
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5710-111685
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of financial or other support the reporting entity has provided (explicitly or implicitly) to the Variable Interest Entity (VIE) that it was not previously contractually required to provide or that the reporting entity intends to provide, including, for example, situations in which the reporting entity assisted the VIE in obtaining another type of support.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 5A -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=64801991&loc=SL6759159-111685
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| X                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
+ Details**Name:**us-gaap_VariableInterestEntityLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                         |
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| X                                                                                                                               |
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| X                                                                                                                               |
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| X                                                                                                                                         |
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| X                                                                                                                                           |
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| X                                                                                                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------|
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