Derivative Financial Instruments Derivative Financial Instruments (Details 3) $ in Millions	Jun. 30, 2020 USD ($) instrument	Dec. 31, 2019 USD ($) instrument
Derivative [Line Items]
Cash collateral pledged for derivatives	$ 134.5	$ 56.6
Risk participation agreement - participant bank
Derivative [Line Items]
Instruments held \| instrument	8	12
Maximum exposure	$ 7.0	$ 3.6
Notional amount	$ 110.7	$ 146.7
Risk participation agreement - lead bank
Derivative [Line Items]
Instruments held \| instrument	16	12
Notional amount	$ 166.9	$ 145.9
Non-hedging \| Commercial loan/lease
Derivative [Line Items]
Credit risk exposure, net of collateral pledged, relating to derivatives	$ 143.1	$ 48.7
Non-hedging \| Interest rate cap \| Commercial loan/lease
Derivative [Line Items]
Weighted average fixed interest rate	3.38%	3.29%
Interest-bearing deposits
Derivative [Line Items]
Cash collateral pledged for derivatives	$ 128.9	$ 54.3
Other assets
Derivative [Line Items]
Cash collateral pledged for derivatives	$ 5.6	$ 2.3

The fair value of cash that serves as collateral for derivatives

No definition available.

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- Definition

Amount the entity is obligated to pay on the credit risk derivatives upon occurrence of a credit event.

+ References

No definition available.

+ Details

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

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- 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

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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12069-110248

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