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Securities (Tables) | 12 Months Ended
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Dec. 31, 2020
Debt Securities, Available-for-sale [Abstract] |
Debt Securities Available for Sale | The following table summarizes the amortized cost, gross unrealized gains and losses and the resulting fair value of debt securities available for sale:
|  | Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Allowance for Credit Losses |  | Fair Value
December 31, 2020 |  | (in thousands)
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations |  | $ | 3,640,351 |  |  | $ | 178,579 |  |  | $ | (4,543) |  |  | $ | — |  |  | $ | 3,814,387 |
Other asset-backed securities |  | 349,904 |  |  | 9,651 |  |  | (2,076) |  |  | — |  |  | 357,479 |
State and municipal securities |  | 729,066 |  |  | 25,098 |  |  | (592) |  |  | — |  |  | 753,572 |
U.S. government agency and government-sponsored enterprise securities |  | 278,208 |  |  | 6,545 |  |  | (57) |  |  | — |  |  | 284,696 |
Total |  | $ | 4,997,529 |  |  | $ | 219,873 |  |  | $ | (7,268) |  |  | $ | — |  |  | $ | 5,210,134 |
December 31, 2019 |  |  |  |  |  |  |  |  |  |
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations |  | $ | 2,864,949 |  |  | $ | 47,223 |  |  | $ | (19,222) |  |  | $ | — |  |  | $ | 2,892,950 |
Other asset-backed securities |  | 194,563 |  |  | 2,476 |  |  | (989) |  |  | — |  |  | 196,050 |
State and municipal securities |  | 478,366 |  |  | 10,660 |  |  | (224) |  |  | — |  |  | 488,802 |
U.S. government agency and government-sponsored enterprise securities |  | 165,218 |  |  | 3,127 |  |  | (5) |  |  | — |  |  | 168,340 |
Total |  | $ | 3,703,096 |  |  | $ | 63,486 |  |  | $ | (20,440) |  |  | $ | — |  |  | $ | 3,746,142 |
Schedule of gross realized gains and losses on sales and calls of securities available for sale | The following table provides the proceeds and both gross realized gains and losses on the sales and calls of debt securities available for sale as well as other securities gains and losses for the periods indicated:
|  | Years Ended December 31,
|  | 2020 |  | 2019 |  | 2018
|  | (in thousands)
Proceeds from sales and calls of debt securities available for sale |  | $ | 194,697 |  |  | $ | 259,554 |  |  | $ | 32,330 |
Gross realized gains from sales of debt securities available for sale |  | $ | 471 |  |  | $ | 3,357 |  |  | $ | 235 |
Gross realized losses from sales of debt securities available for sale |  | (186) |  |  | (1,225) |  |  | (129) |
Other securities gains (losses), net (1) |  | 16,425 |  |  | — |  |  | (195) |
Investment securities gains (losses), net |  | $ | 16,710 |  |  | $ | 2,132 |  |  | $ | (89) |
__________ (1) Other securities gains includes gain from sale of Visa Class B restricted stock and subsequent write up to fair value of remaining Visa Class B shares. See Note 20 “Fair Value Accounting and Measurement” for additional information.
Unrealized gains and losses on equity securities | The following table provides the unrealized gains and losses on equity securities at the reporting date:
|  | Years Ended December 31,
|  | 2020 |  | 2019 |  | 2018
|  | (in thousands)
Gains (losses) recognized during the period on equity securities |  | $ | 16,425 |  |  | $ | — |  |  | $ | (195) |
Less: Losses (gains) recognized during the period on equity securities sold during the period. |  | (3,000) |  |  | — |  |  | 195 |
Unrealized gains recognized during the reporting period on equity securities still held at the reporting date (1). |  | $ | 13,425 |  |  | $ | — |  |  | $ | — |
__________ (1) Visa Class B restricted stock owned by the Company was previously carried at a zero-cost basis due to existing transfer restrictions and uncertainty of covered litigation. The sale of shares by the Company of Visa Class B restricted shares during the year ended December 31, 2020 resulted in an observable market price. As a result, the Company adjusted the carrying value of its remaining shares of Visa Class B restricted shares upward to this observable market price.
Schedule of Contractual Maturities of Investment Securities Available for Sale | The scheduled contractual maturities of debt securities available for sale at December 31, 2020 are presented as follows:
|  | December 31, 2020
|  | Amortized Cost |  | Fair Value
|  | (in thousands)
Due within one year |  | $ | 69,317 |  |  | $ | 69,895 |
Due after one year through five years |  | 713,669 |  |  | 752,119 |
Due after five years through ten years |  | 2,295,998 |  |  | 2,431,876 |
Due after ten years |  | 1,918,545 |  |  | 1,956,244 |
Total debt securities available for sale |  | $ | 4,997,529 |  |  | $ | 5,210,134 |
Schedule of Securities pledged as collateral | The following table summarizes the carrying value of securities pledged as collateral to secure public deposits, borrowings and other purposes as permitted or required by law:
|  | December 31,
|  | 2020 |  | 2019
|  | (in thousands)
To secure public funds |  | $ | 488,119 |  |  | $ | 323,055 |
To secure borrowings |  | 111,695 |  |  | 111,488 |
Other securities pledged |  | 261,760 |  |  | 154,030 |
Total securities pledged as collateral |  | $ | 861,574 |  |  | $ | 588,573 |
Summary of Gross Unrealized Losses and Fair Value of the Investments with Unrealized Losses | The following tables show the gross unrealized losses and fair value of the Company’s debt securities available for sale for which an allowance for credit losses has not been recorded, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at December 31, 2020 and 2019:
|  | Less than 12 Months |  | 12 Months or More |  | Total
|  | Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses
December 31, 2020 |  | (in thousands)
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations |  | $ | 575,329 |  |  | $ | (3,728) |  |  | $ | 18,527 |  |  | $ | (815) |  |  | $ | 593,856 |  |  | $ | (4,543) |
Other asset-backed securities |  | 143,764 |  |  | (2,076) |  |  | 70 |  |  | — |  |  | 143,834 |  |  | (2,076) |
State and municipal securities |  | 86,471 |  |  | (592) |  |  | — |  |  | — |  |  | 86,471 |  |  | (592) |
U.S. government agency and government-sponsored enterprise securities |  | 74,943 |  |  | (57) |  |  | — |  |  | — |  |  | 74,943 |  |  | (57) |
Total |  | $ | 880,507 |  |  | $ | (6,453) |  |  | $ | 18,597 |  |  | $ | (815) |  |  | $ | 899,104 |  |  | $ | (7,268) |
December 31, 2019 |  |  |  |  |  |  |  |  |  |  |  |
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations |  | $ | 1,055,903 |  |  | $ | (12,424) |  |  | $ | 491,539 |  |  | $ | (6,798) |  |  | $ | 1,547,442 |  |  | $ | (19,222) |
Other asset-backed securities |  | 89,508 |  |  | (880) |  |  | 6,799 |  |  | (109) |  |  | 96,307 |  |  | (989) |
State and municipal securities |  | 12,363 |  |  | (142) |  |  | 12,587 |  |  | (82) |  |  | 24,950 |  |  | (224) |
U.S. government agency and government-sponsored enterprise securities |  | — |  |  | — |  |  | 10,495 |  |  | (5) |  |  | 10,495 |  |  | (5) |
Total |  | $ | 1,157,774 |  |  | $ | (13,446) |  |  | $ | 521,420 |  |  | $ | (6,994) |  |  | $ | 1,679,194 |  |  | $ | (20,440) |

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- Definition Schedule of amortized cost and fair value of the debt securities available for sale portfolio of the entity by contractual maturity. The table includes maturity categories of: due in one year or less; due after one year through five years; due after five years through ten years; and due after ten years. A single line item is provided for "total securities with no stated maturity" in order for the total line item of the table to match total available for sale securities. + References No definition available. + Details
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- Definition Schedule reflecting the gross unrealized losses and fair values of the entity's investments, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of the date presented. + References No definition available. + Details
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- Definition Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities. + References No definition available. + Details
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