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v3.22.1

Allowance for Credit Losses (Held-to-Maturity Debt Securities by Credit Quality Indication) (Details) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021 | Mar. 31, 2021
--- | --- | --- | ---
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
Amortized Cost | $ 3,435,888 | $ 2,942,363 | $ 2,166,518
Less: Allowance for credit losses | (159) | (78) | (99)
Held-to-maturity securities, net of allowance for credit losses | 3,435,729 | 2,942,285 | 2,166,419
U.S. Government agencies |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 85,000 |  |
2021 | 147,795 |  |
2020 | 25,000 |  |
2019 | 4,032 |  |
2018 | 0 |  |
Prior | 2,834 |  |
Amortized Cost | 264,661 | 180,192 | 176,160
U.S. Government agencies | 1-4 internal grade |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 85,000 |  |
2021 | 147,795 |  |
2020 | 25,000 |  |
2019 | 4,032 |  |
2018 | 0 |  |
Prior | 2,834 |  |
Amortized Cost | 264,661 |  |
U.S. Government agencies | 5-7 internal grade |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
2019 | 0 |  |
2018 | 0 |  |
Prior | 0 |  |
Amortized Cost | 0 |  |
U.S. Government agencies | 8-10 internal grade |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
2019 | 0 |  |
2018 | 0 |  |
Prior | 0 |  |
Amortized Cost | 0 |  |
Municipal |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 0 |  |
2021 | 7,067 |  |
2020 | 300 |  |
2019 | 160 |  |
2018 | 7,465 |  |
Prior | 165,556 |  |
Amortized Cost | 180,548 | $ 187,486 | $ 197,865
Municipal | 1-4 internal grade |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 0 |  |
2021 | 7,067 |  |
2020 | 300 |  |
2019 | 160 |  |
2018 | 7,465 |  |
Prior | 165,556 |  |
Amortized Cost | 180,548 |  |
Municipal | 5-7 internal grade |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
2019 | 0 |  |
2018 | 0 |  |
Prior | 0 |  |
Amortized Cost | 0 |  |
Municipal | 8-10 internal grade |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
2019 | 0 |  |
2018 | 0 |  |
Prior | 0 |  |
Amortized Cost | 0 |  |
Mortgage-backed securities |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 379,444 |  |
2021 | 2,567,451 |  |
2020 | 0 |  |
2019 | 0 |  |
2018 | 0 |  |
Prior | 0 |  |
Amortized Cost | 2,946,895 |  |
Mortgage-backed securities | 1-4 internal grade |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 379,444 |  |
2021 | 2,567,451 |  |
2020 | 0 |  |
2019 | 0 |  |
2018 | 0 |  |
Prior | 0 |  |
Amortized Cost | 2,946,895 |  |
Mortgage-backed securities | 5-7 internal grade |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
2019 | 0 |  |
2018 | 0 |  |
Prior | 0 |  |
Amortized Cost | 0 |  |
Mortgage-backed securities | 8-10 internal grade |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
2019 | 0 |  |
2018 | 0 |  |
Prior | 0 |  |
Amortized Cost | 0 |  |
Corporate notes |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 6,012 |  |
2019 | 7,377 |  |
2018 | 3,244 |  |
Prior | 27,151 |  |
Amortized Cost | 43,784 |  |
Corporate notes | 1-4 internal grade |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 6,012 |  |
2019 | 7,377 |  |
2018 | 3,244 |  |
Prior | 27,151 |  |
Amortized Cost | 43,784 |  |
Corporate notes | 5-7 internal grade |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
2019 | 0 |  |
2018 | 0 |  |
Prior | 0 |  |
Amortized Cost | 0 |  |
Corporate notes | 8-10 internal grade |  |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
2019 | 0 |  |
2018 | 0 |  |
Prior | 0 |  |
Amortized Cost | $ 0 |  |

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