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v3.20.2

Investments (Details) | 3 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2020 USD ($) security | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) security | Sep. 30, 2019 USD ($) | Dec. 31, 2019 USD ($) security | Jun. 30, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Amortized Cost | $ 6,037,701,000 |  | $ 6,037,701,000 |  | $ 5,562,550,000 |
Allowance for Expected Credit Loss | (362,000) |  | (362,000) |  |  |
Fair Value | 6,344,718,000 |  | 6,344,718,000 |  | 5,737,892,000 |
Other-than-temporary impairment losses recorded in other comprehensive income |  |  |  |  | 0 |
Assets held by insurance regulators | 14,100,000 |  | 14,100,000 |  | $ 13,900,000 |
Increase in credit allowance for the period | 400,000 |  | $ 400,000 |  |  |
Collateral, market value to principal balance of FHLB (as a percent) |  |  | 102.00% |  |  |
FHLB advance, collateral pledged | $ 165,700,000 |  | $ 165,700,000 |  |  |
Number of securities in unrealized loss position (in securities) | security | 197 |  | 197 |  | 217 |
Total fixed income securities |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Amortized Cost | $ 6,037,701,000 |  | $ 6,037,701,000 |  | $ 5,562,550,000 |
Allowance for Expected Credit Loss | (362,000) |  | (362,000) |  |  |
Gross Unrealized Gains | 316,146,000 |  | 316,146,000 |  | 185,244,000 |
Gross Unrealized Losses | (8,767,000) |  | (8,767,000) |  | (9,902,000) |
Fair Value | 6,344,718,000 |  | 6,344,718,000 |  | 5,737,892,000 |
Proceeds from sales of fixed income securities |  |  | 713,100,000 | $ 201,400,000 |  |
Gross realized gains, fixed income securities | 3,400,000 | $ 3,300,000 | 15,900,000 | 5,300,000 |  |
Gross realized losses, fixed income securities | 800,000 | $ 700,000 | 5,900,000 | 3,000,000.0 |  |
Impairment charges recognized on securities with the intent to sell | 400,000 |  | 700,000 |  |  |
Net impairment losses recognized in earnings |  |  |  | $ 100,000 |  |
U.S. Treasury securities and obligations of U.S. government corporations and agencies |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Amortized Cost | 347,249,000 |  | 347,249,000 |  | 195,176,000 |
Allowance for Expected Credit Loss | 0 |  | 0 |  |  |
Gross Unrealized Gains | 1,513,000 |  | 1,513,000 |  | 1,237,000 |
Gross Unrealized Losses | (15,000) |  | (15,000) |  | (210,000) |
Fair Value | 348,747,000 |  | 348,747,000 |  | 196,203,000 |
Obligations of U.S. states and political subdivisions |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Amortized Cost | 1,886,910,000 |  | 1,886,910,000 |  | 1,555,394,000 |
Allowance for Expected Credit Loss | 0 |  | 0 |  |  |
Gross Unrealized Gains | 146,562,000 |  | 146,562,000 |  | 99,328,000 |
Gross Unrealized Losses | (891,000) |  | (891,000) |  | (857,000) |
Fair Value | 2,032,581,000 |  | 2,032,581,000 |  | 1,653,865,000 |
Corporate debt securities |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Amortized Cost | 2,627,745,000 |  | 2,627,745,000 |  | 2,711,910,000 |
Allowance for Expected Credit Loss | 0 |  | 0 |  |  |
Gross Unrealized Gains | 144,646,000 |  | 144,646,000 |  | 76,220,000 |
Gross Unrealized Losses | (2,748,000) |  | (2,748,000) |  | (3,008,000) |
Fair Value | 2,769,643,000 |  | 2,769,643,000 |  | 2,785,122,000 |
Asset backed securities (“ABS”) |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Amortized Cost | 201,731,000 |  | 201,731,000 |  | 227,376,000 |
Allowance for Expected Credit Loss | (362,000) |  | (362,000) |  | 0 | $ 0
Gross Unrealized Gains | 3,472,000 |  | 3,472,000 |  | 2,466,000 |
Gross Unrealized Losses | (145,000) |  | (145,000) |  | (178,000) |
Fair Value | 204,696,000 |  | 204,696,000 |  | 229,664,000 |
Residential mortgage backed securities (“RMBS”) |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Amortized Cost | 398,934,000 |  | 398,934,000 |  | 271,384,000 |
Allowance for Expected Credit Loss | 0 |  | 0 |  |  |
Gross Unrealized Gains | 6,106,000 |  | 6,106,000 |  | 429,000 |
Gross Unrealized Losses | (1,147,000) |  | (1,147,000) |  | (3,227,000) |
Fair Value | 403,893,000 |  | 403,893,000 |  | 268,586,000 |
Commercial mortgage backed securities (“CMBS”) |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Amortized Cost | 258,579,000 |  | 258,579,000 |  | 274,234,000 |
Allowance for Expected Credit Loss | 0 |  | 0 |  |  |
Gross Unrealized Gains | 13,791,000 |  | 13,791,000 |  | 5,531,000 |
Gross Unrealized Losses | (846,000) |  | (846,000) |  | (779,000) |
Fair Value | 271,524,000 |  | 271,524,000 |  | 278,986,000 |
Collateralized loan obligations (“CLOs”) |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Amortized Cost | 312,068,000 |  | 312,068,000 |  | 327,076,000 |
Allowance for Expected Credit Loss | 0 |  | 0 |  |  |
Gross Unrealized Gains | 0 |  | 0 |  | 33,000 |
Gross Unrealized Losses | (2,975,000) |  | (2,975,000) |  | (1,643,000) |
Fair Value | 309,093,000 |  | 309,093,000 |  | $ 325,466,000 |
Debt securities issued by foreign sovereign governments |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Amortized Cost | 4,485,000 |  | 4,485,000 |  |  |
Allowance for Expected Credit Loss | 0 |  | 0 |  |  |
Gross Unrealized Gains | 56,000 |  | 56,000 |  |  |
Gross Unrealized Losses | 0 |  | 0 |  |  |
Fair Value | $ 4,541,000 |  | $ 4,541,000 |  |  |

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