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v3.21.1

Investments (Details) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 USD ($) security | Mar. 31, 2020 USD ($) | Dec. 31, 2020 USD ($) security
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | $ 6,586,020 |  | $ 6,317,164
Fair Value | 6,811,318 |  | 6,661,596
Assets held by insurance regulatory requirements | 13,900 |  | 14,100
Assets held in trust for the benefit of contractual counterparties | $ 167,700 |  | 160,300
Collateral, market value to principal balance of FHLB (as a percent) | 102.00% |  |
FHLB advance, collateral pledged | $ 164,100 |  | $ 163,900
Number of securities in unrealized loss position (in securities) | security | 403 |  | 109
Total fixed income securities |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | $ 6,586,020 |  | $ 6,317,164
Allowance for Expected Credit Loss | (31) | $ 0 | (49)
Gross Unrealized Gains | 259,132 |  | 349,140
Gross Unrealized Losses | (33,803) |  | (4,659)
Fair Value | 6,811,318 |  | 6,661,596
Proceeds from sales of fixed income securities | 56,800 | 212,800 |
Gross realized gains, fixed income securities | 3,000 | 5,100 |
Gross realized losses, fixed income securities | 400 | 1,300 |
Impairment charges recognized on securities with the intent to sell | 0 | $ 300 |
Increase (decrease) in credit allowance for the period | (18) |  |
U.S. Treasury securities and obligations of U.S. government corporations and agencies |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 252,806 |  | 264,531
Allowance for Expected Credit Loss | 0 |  | 0
Gross Unrealized Gains | 873 |  | 1,164
Gross Unrealized Losses | (222) |  | (2)
Fair Value | 253,457 |  | 265,693
Obligations of U.S. states and political subdivisions |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 2,249,876 |  | 2,083,568
Allowance for Expected Credit Loss | 0 |  | 0
Gross Unrealized Gains | 132,869 |  | 166,557
Gross Unrealized Losses | (14,727) |  | (256)
Fair Value | 2,368,018 |  | 2,249,869
Corporate debt securities |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 2,771,839 |  | 2,690,860
Allowance for Expected Credit Loss | 0 |  | 0
Gross Unrealized Gains | 104,279 |  | 155,156
Gross Unrealized Losses | (14,990) |  | (1,728)
Fair Value | 2,861,128 |  | 2,844,288
ABS |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 185,394 |  | 203,807
Allowance for Expected Credit Loss | (31) |  | (49)
Gross Unrealized Gains | 2,000 |  | 2,946
Gross Unrealized Losses | (222) |  | (18)
Fair Value | 187,141 |  | 206,686
RMBS |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 432,148 |  | 425,532
Allowance for Expected Credit Loss | 0 |  | 0
Gross Unrealized Gains | 5,270 |  | 6,472
Gross Unrealized Losses | (1,410) |  | (838)
Fair Value | 436,008 |  | 431,166
CMBS |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 317,055 |  | 312,572
Allowance for Expected Credit Loss | 0 |  | 0
Gross Unrealized Gains | 12,875 |  | 16,055
Gross Unrealized Losses | (2,080) |  | (1,125)
Fair Value | 327,850 |  | 327,502
CLOs |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 372,417 |  | 310,616
Allowance for Expected Credit Loss | 0 |  | 0
Gross Unrealized Gains | 966 |  | 566
Gross Unrealized Losses | (56) |  | (692)
Fair Value | 373,327 |  | 310,490
Foreign government debt |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 4,485 |  | 4,485
Allowance for Expected Credit Loss | 0 |  | 0
Gross Unrealized Gains | 0 |  | 224
Gross Unrealized Losses | (96) |  | 0
Fair Value | $ 4,389 |  | 4,709
Commercial paper |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost |  |  | 21,193
Allowance for Expected Credit Loss |  |  | 0
Gross Unrealized Gains |  |  | 0
Gross Unrealized Losses |  |  | 0
Fair Value |  |  | $ 21,193

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