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v3.19.2

Investments (Details) | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2019 USD ($) security | Jun. 30, 2018 USD ($) | Jun. 30, 2019 USD ($) security | Jun. 30, 2018 USD ($) | Dec. 31, 2018 USD ($) security
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Amortized Cost | $ 5,357,436,000 |  | $ 5,357,436,000 |  | $ 5,196,784,000
Fair Value | 5,504,823,000 |  | 5,504,823,000 |  | 5,151,987,000
Other-than-temporary impairment losses |  |  | 0 |  | 0
Assets held by insurance regulators | 13,700,000 |  | 13,700,000 |  | $ 13,500,000
Proceeds from sales of fixed income securities |  |  | 183,600,000 | $ 25,100,000 |
Net impairment losses recognized in earnings |  | $ 1,300,000 | $ 100,000 | 1,300,000 |
Federal Home Loan Bank advances, collateral, value of principal, percent (as a percent) |  |  | 102.00% |  |
FHLB advance collateral | $ 163,000,000.0 |  | $ 163,000,000.0 |  |
Number of securities in unrealized loss position (in securities) | security | 243 |  | 243 |  | 721
Total fixed income securities |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Amortized Cost | $ 5,357,436,000 |  | $ 5,357,436,000 |  | $ 5,196,784,000
Gross Unrealized Gains | 158,787,000 |  | 158,787,000 |  | 33,107,000
Gross Unrealized Losses | (11,400,000) |  | (11,400,000) |  | (77,904,000)
Fair Value | 5,504,823,000 |  | 5,504,823,000 |  | 5,151,987,000
Gross realized gains, fixed income securities | 1,200,000 | 100,000 | 2,000,000.0 | 200,000 |
Gross realized losses, fixed income securities | 1,100,000 | $ 600,000 | 2,300,000 | $ 1,000,000.0 |
U.S. Treasury securities and obligations of U.S. government corporations and agencies |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Amortized Cost | 194,222,000 |  | 194,222,000 |  | 167,655,000
Gross Unrealized Gains | 1,474,000 |  | 1,474,000 |  | 597,000
Gross Unrealized Losses | (127,000) |  | (127,000) |  | (1,076,000)
Fair Value | 195,569,000 |  | 195,569,000 |  | 167,176,000
Obligations of U.S. states and political subdivisions |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Amortized Cost | 1,566,166,000 |  | 1,566,166,000 |  | 1,701,826,000
Gross Unrealized Gains | 88,379,000 |  | 88,379,000 |  | 29,259,000
Gross Unrealized Losses | (648,000) |  | (648,000) |  | (10,985,000)
Fair Value | 1,653,897,000 |  | 1,653,897,000 |  | 1,720,100,000
Corporate debt securities |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Amortized Cost | 2,570,289,000 |  | 2,570,289,000 |  | 2,439,173,000
Gross Unrealized Gains | 61,459,000 |  | 61,459,000 |  | 2,103,000
Gross Unrealized Losses | (3,134,000) |  | (3,134,000) |  | (40,514,000)
Fair Value | 2,628,614,000 |  | 2,628,614,000 |  | 2,400,762,000
Asset backed securities (“ABS”) |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Amortized Cost | 215,016,000 |  | 215,016,000 |  | 111,953,000
Gross Unrealized Gains | 2,787,000 |  | 2,787,000 |  | 226,000
Gross Unrealized Losses | (102,000) |  | (102,000) |  | (146,000)
Fair Value | 217,701,000 |  | 217,701,000 |  | 112,033,000
Residential mortgage backed securities (“RMBS”) |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Amortized Cost | 213,024,000 |  | 213,024,000 |  | 189,238,000
Gross Unrealized Gains | 183,000 |  | 183,000 |  | 32,000
Gross Unrealized Losses | (4,710,000) |  | (4,710,000) |  | (10,309,000)
Fair Value | 208,497,000 |  | 208,497,000 |  | 178,961,000
Commercial mortgage backed securities (“CMBS”) |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Amortized Cost | 268,189,000 |  | 268,189,000 |  | 276,352,000
Gross Unrealized Gains | 4,450,000 |  | 4,450,000 |  | 888,000
Gross Unrealized Losses | (750,000) |  | (750,000) |  | (9,580,000)
Fair Value | 271,889,000 |  | 271,889,000 |  | 267,660,000
Collateralized loan obligations (“CLO”) |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Amortized Cost | 330,530,000 |  | 330,530,000 |  | 310,587,000
Gross Unrealized Gains | 55,000 |  | 55,000 |  | 2,000
Gross Unrealized Losses | (1,929,000) |  | (1,929,000) |  | (5,294,000)
Fair Value | $ 328,656,000 |  | $ 328,656,000 |  | $ 305,295,000

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