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SCHEDULE I - SUMMARY OF INVESTMENTS - OTHER THAN INVESTMENTS IN RELATED PARTIES (Details) $ in Thousands | Dec. 31, 2019 USD ($)
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SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |
Amortized Cost | $ 5,579,738
Fair Value | 5,755,220
Amount at which shown in the balance sheet | 5,755,220
Fixed income |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |
Amortized Cost | 5,562,550
Fair Value | 5,737,892
Amount at which shown in the balance sheet | 5,737,892
Fixed income | U.S. Treasury securities and obligations of U.S. government corporations and agencies |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |
Amortized Cost | 195,176
Fair Value | 196,203
Amount at which shown in the balance sheet | 196,203
Fixed income | Obligations of U.S. states and political subdivisions |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |
Amortized Cost | 1,555,394
Fair Value | 1,653,865
Amount at which shown in the balance sheet | 1,653,865
Fixed income | Public utilities |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |
Amortized Cost | 270,675
Fair Value | 278,991
Amount at which shown in the balance sheet | 278,991
Fixed income | ABS |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |
Amortized Cost | 227,376
Fair Value | 229,664
Amount at which shown in the balance sheet | 229,664
Fixed income | Collateralized loan obligations |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |
Amortized Cost | 327,076
Fair Value | 325,466
Amount at which shown in the balance sheet | 325,466
Fixed income | Mortgage-backed |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |
Amortized Cost | 545,618
Fair Value | 547,572
Amount at which shown in the balance sheet | 547,572
Fixed income | All other corporate bonds |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |
Amortized Cost | 2,441,235
Fair Value | 2,506,131
Amount at which shown in the balance sheet | 2,506,131
Equity Securities |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |
Amortized Cost | 17,188
Fair Value | 17,328
Amount at which shown in the balance sheet | 17,328
Equity Securities | Industrial, miscellaneous and all other |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |
Amortized Cost | 17,188
Fair Value | 17,328
Amount at which shown in the balance sheet | $ 17,328

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