Loan Portfolio and Credit Quality Narrative (Details) $ in Millions	Mar. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged in blanket lien agreement	$ 2,300.0	$ 2,500.0
Loans pledged as collateral	386.2	395.3
TDRs	14.9	12.6
Deferred income	7.7	8.1
Performing Financial Instruments
Accounts, Notes, Loans and Financing Receivable [Line Items]
TDRs	$ 7.1	$ 7.1
Residential \| 90 Days or Greater Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans \| loan	0	0

Financing Receivable Number Of Contracts Past Due

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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.

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

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- Definition

The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of FHLB debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

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- Definition

The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of other debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

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