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v3.20.1

Investments (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 USD ($) security | Mar. 31, 2019 USD ($) | Dec. 31, 2019 USD ($) security
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | $ 5,375,382,000 |  | $ 5,562,550,000
Fair Value | 5,458,846,000 |  | 5,737,892,000
Credit allowance on available for sale fixed income securities | 0 |  |
Other-than-temporary impairment losses recorded in other comprehensive income |  |  | 0
Assets held by insurance regulators | 14,200,000 |  | $ 13,900,000
Impairment charges recognized in net realized gains (losses) on securities with the intent to sell | $ (300,000) |  |
Net impairment losses recognized in earnings |  | $ (100,000) |
Collateral, market value to principal balance of FHLB (as a percent) | 102.00% |  |
FHLB advance, collateral pledged | $ 164,900,000 |  |
Number of securities in unrealized loss position (in securities) | security | 321 |  | 217
Total fixed income securities |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | $ 5,375,382,000 |  | $ 5,562,550,000
Gross Unrealized Gains | 157,550,000 |  | 185,244,000
Gross Unrealized Losses | (74,086,000) |  | (9,902,000)
Fair Value | 5,458,846,000 |  | 5,737,892,000
Proceeds from sales of fixed income securities | 212,800,000 | 106,000,000.0 |
Gross realized gains, fixed income securities | 5,100,000 | 700,000 |
Gross realized losses, fixed income securities | (1,300,000) | $ (1,300,000) |
U.S. Treasury securities and obligations of U.S. government corporations and agencies |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 197,330,000 |  | 195,176,000
Gross Unrealized Gains | 2,408,000 |  | 1,237,000
Gross Unrealized Losses | (21,000) |  | (210,000)
Fair Value | 199,717,000 |  | 196,203,000
Obligations of U.S. states and political subdivisions |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 1,614,562,000 |  | 1,555,394,000
Gross Unrealized Gains | 99,532,000 |  | 99,328,000
Gross Unrealized Losses | (3,258,000) |  | (857,000)
Fair Value | 1,710,836,000 |  | 1,653,865,000
Corporate debt securities |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 2,508,051,000 |  | 2,711,910,000
Gross Unrealized Gains | 44,386,000 |  | 76,220,000
Gross Unrealized Losses | (41,335,000) |  | (3,008,000)
Fair Value | 2,511,102,000 |  | 2,785,122,000
Asset backed securities (“ABS”) |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 210,930,000 |  | 227,376,000
Gross Unrealized Gains | 2,031,000 |  | 2,466,000
Gross Unrealized Losses | (6,311,000) |  | (178,000)
Fair Value | 206,650,000 |  | 229,664,000
Residential mortgage backed securities (“RMBS”) |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 259,641,000 |  | 271,384,000
Gross Unrealized Gains | 6,032,000 |  | 429,000
Gross Unrealized Losses | (758,000) |  | (3,227,000)
Fair Value | 264,915,000 |  | 268,586,000
Commercial mortgage backed securities (“CMBS”) |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 268,598,000 |  | 274,234,000
Gross Unrealized Gains | 3,161,000 |  | 5,531,000
Gross Unrealized Losses | (3,172,000) |  | (779,000)
Fair Value | 268,587,000 |  | 278,986,000
Collateralized loan obligations (“CLOs”) |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Amortized Cost | 316,270,000 |  | 327,076,000
Gross Unrealized Gains | 0 |  | 33,000
Gross Unrealized Losses | (19,231,000) |  | (1,643,000)
Fair Value | $ 297,039,000 |  | $ 325,466,000

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