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Investments (Tables) | 9 Months Ended
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Sep. 30, 2021
Gross Unrecognized Gains and Losses and Cost or Amortized Cost, Allowance for Credit Losses, Carrying Amount and Fair Value of Investments Classified as Held-to-Maturity | The amortized cost, allowance for credit losses, carrying amount, gross unrecognized gains and losses, and the fair value of those investments classified as held-to-maturity at September 30, 2021 are summarized as follows:
|  | Amortized Cost |  |  | Allowance for Credit Losses |  |  | Carrying Amount |  |  | Gross Unrecognized Gains |  |  | Gross Unrecognized Losses |  |  | Fair Value |
|  | (in thousands) |
States and political subdivisions |  | $ | 469,445 |  |  | $ | (45 | ) |  | $ | 469,400 |  |  | $ | 25,849 |  |  | $ | (158 | ) |  | $ | 495,091 |
Corporate bonds |  |  | 51,974 |  |  |  | (123 | ) |  |  | 51,851 |  |  |  | 1,892 |  |  |  | (4 | ) |  |  | 53,739 |
U.S. agency-based mortgage-backed securities |  |  | 5,060 |  |  |  | — |  |  |  | 5,060 |  |  |  | 474 |  |  |  | — |  |  |  | 5,534 |
U.S. Treasury securities and obligations of U.S. government agencies |  |  | 14,801 |  |  |  | — |  |  |  | 14,801 |  |  |  | 167 |  |  |  | (4 | ) |  |  | 14,964 |
Asset-backed securities |  |  | 116 |  |  |  | (4 | ) |  |  | 112 |  |  |  | 5 |  |  |  | — |  |  |  | 117 |
Totals |  | $ | 541,396 |  |  | $ | (172 | ) |  | $ | 541,224 |  |  | $ | 28,387 |  |  | $ | (166 | ) |  | $ | 569,445 |
The amortized cost, allowance for credit losses, carrying amount, gross unrecognized gains and losses, and the fair value of those investments classified as held-to-maturity at December 31, 2020 are summarized as follows:
|  | Amortized Cost |  |  | Allowance for Credit Losses |  |  | Carrying Amount |  |  | Gross Unrecognized Gains |  |  | Gross Unrecognized Losses |  |  | Fair Value |
|  | (in thousands) |
States and political subdivisions |  | $ | 494,374 |  |  | $ | (42 | ) |  | $ | 494,332 |  |  | $ | 32,489 |  |  | $ | — |  |  | $ | 526,821 |
Corporate bonds |  |  | 69,981 |  |  |  | (225 | ) |  |  | 69,756 |  |  |  | 3,144 |  |  |  | — |  |  |  | 72,900 |
U.S. agency-based mortgage-backed securities |  |  | 7,261 |  |  |  | — |  |  |  | 7,261 |  |  |  | 645 |  |  |  | — |  |  |  | 7,906 |
U.S. Treasury securities and obligations of U.S. government agencies |  |  | 13,626 |  |  |  | — |  |  |  | 13,626 |  |  |  | 239 |  |  |  | — |  |  |  | 13,865 |
Asset-backed securities |  |  | 162 |  |  |  | (7 | ) |  |  | 155 |  |  |  | 7 |  |  |  | — |  |  |  | 162 |
Totals |  | $ | 585,404 |  |  | $ | (274 | ) |  | $ | 585,130 |  |  | $ | 36,524 |  |  | $ | — |  |  | $ | 621,654 |
Gross Unrealized Gains and Losses and Cost or Amortized Cost, Allowance for Credit Losses and Fair Value of Investments Classified as Available-for-sale | The amortized cost, gross unrealized gains and losses, fair value, and the allowance for credit losses of those investments classified as available-for-sale at September 30, 2021 are summarized as follows:
|  | Amortized Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |  |  | Allowance for Credit Losses |
|  | (in thousands) |
States and political subdivisions |  | $ | 209,354 |  |  | $ | 15,010 |  |  | $ | (105 | ) |  | $ | 224,259 |  |  | $ | — |
Corporate bonds |  |  | 79,336 |  |  |  | 3,500 |  |  |  | (99 | ) |  |  | 82,737 |  |  |  | — |
U.S. agency-based mortgage-backed securities |  |  | 9,487 |  |  |  | 237 |  |  |  | (9 | ) |  |  | 9,715 |  |  |  | — |
U.S. Treasury securities and obligations of U.S. government agencies |  |  | 24,686 |  |  |  | 518 |  |  |  | (77 | ) |  |  | 25,127 |  |  |  | — |
Totals |  | $ | 322,863 |  |  | $ | 19,265 |  |  | $ | (290 | ) |  | $ | 341,838 |  |  | $ | — |
The amortized cost, gross unrealized gains and losses, fair value, and the allowance for credit losses of those investments classified as available-for-sale at December 31, 2020 are summarized as follows:
|  | Amortized Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |  |  | Allowance for Credit Losses |
|  | (in thousands) |
States and political subdivisions |  | $ | 256,492 |  |  | $ | 20,050 |  |  | $ | — |  |  | $ | 276,542 |  |  | $ | — |
Corporate bonds |  |  | 83,646 |  |  |  | 5,256 |  |  |  | (3 | ) |  |  | 88,899 |  |  |  | — |
U.S. agency-based mortgage-backed securities |  |  | 18,654 |  |  |  | 400 |  |  |  | (2 | ) |  |  | 19,052 |  |  |  | — |
U.S. Treasury securities and obligations of U.S. government agencies |  |  | 28,873 |  |  |  | 913 |  |  |  | — |  |  |  | 29,786 |  |  |  | — |
Totals |  | $ | 387,665 |  |  | $ | 26,619 |  |  | $ | (5 | ) |  | $ | 414,279 |  |  | $ | — |
Gross Unrealized Gains and Losses and Cost of Equity | The cost, gross unrealized gains and losses, and the fair value of equity securities at September 30, 2021 are summarized as follows:
|  | Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
|  | (in thousands) |
Equity securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Domestic common stock |  | $ | 40,674 |  |  | $ | 15,677 |  |  | $ | — |  |  | $ | 56,351 |
Total equity securities |  | $ | 40,674 |  |  | $ | 15,677 |  |  | $ | — |  |  | $ | 56,351 |
The cost, gross unrealized gains and losses, and the fair value of equity securities at December 31, 2020 are summarized as follows:
|  | Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
|  | (in thousands) |
Equity securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Domestic common stock |  | $ | 35,787 |  |  | $ | 7,650 |  |  | $ | — |  |  | $ | 43,437 |
Total equity securities |  | $ | 35,787 |  |  | $ | 7,650 |  |  | $ | — |  |  | $ | 43,437 |
Investment Securities Continuous Unrealized Loss Position | The following table summarizes the fair value and gross unrealized losses on securities classified as available-for-sale, aggregated by major investment category and length of time that the individual securities have been in a continuous unrealized loss position as of September 30, 2021:
|  | Less Than 12 Months |  |  | 12 Months or Greater |  |  | Total |
|  | Fair Value of Investments with Unrealized Losses |  |  | Gross Unrealized Losses |  |  | Fair Value of Investments with Unrealized Losses |  |  | Gross Unrealized Losses |  |  | Fair Value of Investments with Unrealized Losses |  |  | Gross Unrealized Losses |
|  | (in thousands) |
September 30, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Available-for-Sale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
States and political subdivisions |  | $ | 6,992 |  |  | $ | 105 |  |  | $ | — |  |  | $ | — |  |  | $ | 6,992 |  |  | $ | 105 |
Corporate bonds |  |  | 11,504 |  |  |  | 99 |  |  |  | — |  |  |  | — |  |  |  | 11,504 |  |  |  | 99 |
U.S. agency-based mortgage-backed securities |  |  | 1,337 |  |  |  | 9 |  |  |  | — |  |  |  | — |  |  |  | 1,337 |  |  |  | 9 |
U.S. Treasury securities and obligations of U.S. government agencies |  |  | 6,821 |  |  |  | 77 |  |  |  | — |  |  |  | — |  |  |  | 6,821 |  |  |  | 77 |
Total available-for-sale securities |  | $ | 26,654 |  |  | $ | 290 |  |  | $ | — |  |  | $ | — |  |  | $ | 26,654 |  |  | $ | 290 |
The following table summarizes the fair value and gross unrealized losses on securities classified as available-for-sale, aggregated by major investment category and length of time that the individual securities have been in a continuous unrealized loss position as of December 31, 2020:
|  | Less Than 12 Months |  |  | 12 Months or Greater |  |  | Total |
|  | Fair Value of Investments with Unrealized Losses |  |  | Gross Unrealized Losses |  |  | Fair Value of Investments with Unrealized Losses |  |  | Gross Unrealized Losses |  |  | Fair Value of Investments with Unrealized Losses |  |  | Gross Unrealized Losses |
|  | (in thousands) |
December 31, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Available-for-Sale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate bonds |  | $ | 2,515 |  |  | $ | 3 |  |  | $ | — |  |  | $ | — |  |  | $ | 2,515 |  |  | $ | 3 |
U.S. agency-based mortgage-backed securities |  |  | 2,133 |  |  |  | 2 |  |  |  | — |  |  |  | — |  |  |  | 2,133 |  |  |  | 2 |
Total available-for-sale securities |  | $ | 4,648 |  |  | $ | 5 |  |  | $ | — |  |  | $ | — |  |  | $ | 4,648 |  |  | $ | 5 |
Changes in Allowance for Credit Losses by Major Security Type of Investments Classified as Held-to-Maturity | The following table illustrates the changes in the allowance for credit losses by major security type of the investments classified as held-to-maturity for the quarter ended September 30, 2021.
|  | States and Political Subdivisions |  |  | Corporate Bonds |  |  | U.S. Agency-Based Mortgage-Backed Securities |  |  | U.S. Treasury Securities and Obligations of U.S. Government Agencies |  |  | Asset-Backed Securities |  |  | Totals |
|  | (in thousands) |
Balance at June 30, 2021 |  | $ | 41 |  |  | $ | 111 |  |  | $ | — |  |  | $ | — |  |  | $ | 5 |  |  | $ | 157 |
Provision for credit loss expense (benefit) |  |  | 4 |  |  |  | 12 |  |  |  | — |  |  |  | — |  |  |  | (1 | ) |  |  | 15 |
Balance at September 30, 2021 |  | $ | 45 |  |  | $ | 123 |  |  | $ | — |  |  | $ | — |  |  | $ | 4 |  |  | $ | 172 |
The following table illustrates the changes in the allowance for credit losses by major security type of the investments classified as held-to-maturity for the nine months ended September 30, 2021.
|  | States and Political Subdivisions |  |  | Corporate Bonds |  |  | U.S. Agency-Based Mortgage-Backed Securities |  |  | U.S. Treasury Securities and Obligations of U.S. Government Agencies |  |  | Asset-Backed Securities |  |  | Totals |
|  | (in thousands) |
Balance at December 31, 2020 |  | $ | 42 |  |  | $ | 225 |  |  | $ | — |  |  | $ | — |  |  | $ | 7 |  |  | $ | 274 |
Provision for credit loss expense (benefit) |  |  | 3 |  |  |  | (102 | ) |  |  | — |  |  |  | — |  |  |  | (3 | ) |  |  | (102 | )
Balance at September 30, 2021 |  | $ | 45 |  |  | $ | 123 |  |  | $ | — |  |  | $ | — |  |  | $ | 4 |  |  | $ | 172 |
Schedule of Amortized Cost Held-to-Maturity Securities Aggregated By Credit Quality Indicator | The table below presents the amortized cost of held-to-maturity securities aggregated by credit quality indicator as of September 30, 2021.
|  | States and Political Subdivisions |  |  | Corporate Bonds |  |  | U.S. Agency-Based Mortgage-Backed Securities |  |  | U.S. Treasury Securities and Obligations of U.S. Government Agencies |  |  | Asset-Backed Securities |  |  | Totals |
|  | Amortized cost |
|  | (in thousands) |
AAA/AA/A ratings |  | $ | 466,450 |  |  | $ | 22,647 |  |  | $ | 5,060 |  |  | $ | 14,801 |  |  | $ | 79 |  |  | $ | 509,037 |
Baa/BBB ratings |  |  | 2,995 |  |  |  | 29,327 |  |  |  | — |  |  |  | — |  |  |  | 16 |  |  |  | 32,338 |
B ratings |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 21 |  |  |  | 21 |
Total |  | $ | 469,445 |  |  | $ | 51,974 |  |  | $ | 5,060 |  |  | $ | 14,801 |  |  | $ | 116 |  |  | $ | 541,396 |
Held-to-Maturity Securities [Member] |
Summary of Carrying Amount, Amortized Cost and Fair Value of Investments in Fixed Maturity Securities, by Contractual Maturity | A summary of the carrying amounts and fair value of investments in fixed maturity securities classified as held-to-maturity, by contractual maturity, is as follows:
|  | September 30, 2021 |  |  | December 31, 2020 |
|  | Carrying Amount |  |  | Fair Value |  |  | Carrying Amount |  |  | Fair Value |
|  | (in thousands) |
Maturity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Within one year |  | $ | 57,626 |  |  | $ | 58,183 |  |  | $ | 54,316 |  |  | $ | 54,794 |
After one year through five years |  |  | 169,880 |  |  |  | 176,260 |  |  |  | 195,706 |  |  |  | 204,289 |
After five years through ten years |  |  | 105,046 |  |  |  | 110,513 |  |  |  | 107,347 |  |  |  | 113,643 |
After ten years |  |  | 203,500 |  |  |  | 218,838 |  |  |  | 220,345 |  |  |  | 240,860 |
U.S. agency-based mortgage-backed securities |  |  | 5,060 |  |  |  | 5,534 |  |  |  | 7,261 |  |  |  | 7,906 |
Asset-backed securities |  |  | 112 |  |  |  | 117 |  |  |  | 155 |  |  |  | 162 |
Totals |  | $ | 541,224 |  |  | $ | 569,445 |  |  | $ | 585,130 |  |  | $ | 621,654 |
Available-for-Sale Securities [Member] |
Summary of Carrying Amount, Amortized Cost and Fair Value of Investments in Fixed Maturity Securities, by Contractual Maturity | A summary of the amortized cost and fair value of investments in fixed maturity securities classified as available-for-sale, by contractual maturity, is as follows:
|  | September 30, 2021 |  |  | December 31, 2020 |
|  | Amortized Cost |  |  | Fair Value |  |  | Amortized Cost |  |  | Fair Value |
|  | (in thousands) |
Maturity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Within one year |  | $ | 32,152 |  |  | $ | 32,718 |  |  | $ | 69,177 |  |  | $ | 69,938 |
After one year through five years |  |  | 88,065 |  |  |  | 92,012 |  |  |  | 80,593 |  |  |  | 85,829 |
After five years through ten years |  |  | 56,405 |  |  |  | 58,625 |  |  |  | 53,835 |  |  |  | 57,829 |
After ten years |  |  | 136,754 |  |  |  | 148,768 |  |  |  | 165,406 |  |  |  | 181,631 |
U.S. agency-based mortgage-backed securities |  |  | 9,487 |  |  |  | 9,715 |  |  |  | 18,654 |  |  |  | 19,052 |
Totals |  | $ | 322,863 |  |  | $ | 341,838 |  |  | $ | 387,665 |  |  | $ | 414,279 |

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