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Nature of Operations and Summary of Significant Accounting Policies Bank-Owned Life Insurance (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Bank owned life insurance death benefits	$ 136.1	$ 97.9
Borrowings against cash surrender value of bank owned life insurance	$ 0.0	$ 0.0

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- Definition

Bank Owned Life Insurance Death Benefits

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- Definition

Borrowings Against Cash Surrender Value of Bank Owned Life Insurance

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