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v3.20.1

Reinsurance (List of Direct, Assumed, and Ceded Reinsurance Amounts) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Premiums written: |  |
Direct | $ 746,431 | $ 766,394
Assumed | 6,043 | 6,555
Ceded | (105,147) | (100,002)
Net | 647,327 | 672,947
Premiums earned: |  |
Direct | 754,892 | 728,037
Assumed | 6,173 | 6,562
Ceded | (109,362) | (102,026)
Net | 651,703 | 632,573
Loss and loss expenses incurred: |  |
Direct | 425,795 | 424,657
Assumed | 4,898 | 5,265
Ceded | (30,369) | (43,343)
Net | 400,324 | $ 386,579
COVID-19 [Member] |  |
Effects of Reinsurance [Line Items] |  |
Premium audit accrual decrease | $ 75,000 |

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