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v3.21.2

Securities (Narrative) (Details) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2021 USD ($) security | Sep. 30, 2020 USD ($) | Sep. 30, 2021 USD ($) security | Sep. 30, 2020 USD ($) | Dec. 31, 2020 USD ($) security
Unrealized Loss |  |  |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security | 359 |  | 359 |  | 104
Available-for-sale debt securities, in gross unrealized loss position |  |  | $ 0 |  | $ 0
Debt Securities, AFS, allowance for credit loss | $ 0 |  | 0 |  | $ 0
(Reversal of) provision for credit losses | (10,000,000) | $ 10,000,000 | (25,000,000) | $ 186,313,000 |
AFS debt securities |  |  |  |  |
Unrealized Loss |  |  |  |  |
(Reversal of) provision for credit losses | $ 0 | $ 0 | $ 0 | $ 0 |
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities |  |  |  |  |
Unrealized Loss |  |  |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security | 150 |  | 150 |  | 46
U.S. government-sponsored enterprises debt securities |  |  |  |  |
Unrealized Loss |  |  |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security | 48 |  | 48 |  |
Corporate debt securities |  |  |  |  |
Unrealized Loss |  |  |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security | 22 |  | 22 |  | 17
AFS debt securities |  |  |  |  |
Unrealized Loss |  |  |  |  |
Excluded accrued interest receivables | $ 27,000,000 |  | $ 27,000,000 |  | $ 22,300,000

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