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Other Real Estate Owned (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Repossessed Assets [Abstract] |  |  |
Real Estate Acquired Through Foreclosure, Valuation Adjustments | $ 0.0 | $ 0.1 |
Real Estate Acquired Through Foreclosure [Roll Forward] |  |  |
Balance at beginning of year | 2.5 | 8.5 | $ 14.4
OREO acquired through acquisitions | 0.0 | 0.0 | 2.4
Additions | 0.9 | 3.3 | 14.1
Valuation adjustments | 0.0 | (0.1) | (0.9)
Dispositions | (1.4) | (9.2) | (21.8)
Balance at end of year | 2.0 | 2.5 | 8.5
Real Estate Acquired Through Foreclosure, Improvements | 0.0 | 0.0 | 0.3
Write-downs of OREO | 0.0 | (0.1) | $ (0.9)
Mortgage Loans in Process of Foreclosure, Amount | 0.2 | 0.2 |
Carrying value of foreclosed OREO | $ 0.2 | $ 0.0 |

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- Definition The charge against earnings in the period to reduce the carrying amount of real property to fair value. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230 + Details
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