Servicing Rights - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Off-balance Sheet Risks, Disclosure Information [Line Items]
Contractually specified servicing fees, late fees, and other ancillary fees	$ 4.4	$ 3.5
Mortgage servicing rights
Off-balance Sheet Risks, Disclosure Information [Line Items]
The unpaid principal balances of mortgage loans serviced	2,170.0	1,460.0
Fair market value of servicing rights' assets	$ 12.8	$ 13.3

Amount of contractually specified servicing fee, late fee, and ancillary fee recognized as income for servicing asset and servicing liability.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122596-111746

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- Definition

The fair value of financial assets, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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The face amount of financial assets, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

No definition available.

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- Definition

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+ References

No definition available.

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