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Securities - Narrative (Details) | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2022 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2022 USD ($) | Jun. 30, 2021 USD ($) | Dec. 31, 2021 USD ($)
Schedule of Investments [Line Items] |  |  |  |  |
Debt Securities, Available-for-sale, Allowance for Credit Loss | $ 0 |  | $ 0 |  | $ 0
Transferred Securities, Unrealized Loss, Before Tax | 91,500,000 |  | 91,500,000 |  | 1,500,000
Securities transferred, Unrealized Loss, Net of Tax | 72,300,000 |  | 72,300,000 |  | 1,200,000
Fair value of securities transferred from AFS to HTM |  |  | 998,500,000 |  | 0
Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract] |  |  |  |  |
Net gain (loss) on sale of securities AFS | (2,177,000) | $ 15,000 | (3,720,000) | $ 2,018,000 |
Gross realized gains on AFS securities |  |  | 290,000 | 2,100,000 |
Gross realized losses on AFS securities |  |  | 4,000,000 | 52,000 |
Equity investments | 11,282,000 |  | 11,282,000 |  | 11,841,000
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract] |  |  |  |  |
Sale of HTM portfolio |  |  | 0 | 0 |
Interest receivable | 41,539,000 |  | 41,539,000 |  | 39,145,000
Debt Securities, Held-to-maturity, Nonaccrual | 0 |  | 0 |  | 0
FHLB stock with other-than-temporary impairment | 0 |  | 0 |  |
Other-than-temporarily impaired equity investments | $ 0 |  | $ 0 |  |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | 644 |  | 644 |  |
State and political subdivisions |  |  |  |  |
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract] |  |  |  |  |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, Credit Loss Expense (Reversal) | $ 0 | 0 | $ 0 | 0 |
Corporate bonds and other |  |  |  |  |
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract] |  |  |  |  |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, Credit Loss Expense (Reversal) | 0 | $ 0 | 0 | $ 0 |
Asset Pledged as Collateral |  |  |  |  |
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract] |  |  |  |  |
Debt Securities | 1,410,000,000 |  | 1,410,000,000 |  | 1,610,000,000
Financial Asset, Past Due |  |  |  |  |
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract] |  |  |  |  |
Securities held to maturity (estimated fair value of $138,879) | 0 |  | 0 |  | 0
Available-for-sale Securities |  |  |  |  |
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract] |  |  |  |  |
Interest receivable | 16,100,000 |  | 16,100,000 |  | 25,600,000
Held-to-maturity Securities |  |  |  |  |
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract] |  |  |  |  |
Interest receivable | $ 10,900,000 |  | $ 10,900,000 |  | $ 244,000

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