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Reinsurance (List of direct, assumed and ceded Reinsurance Amounts) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Premiums Written: |  |  |
Direct premiums written | $ 3,656,537 | $ 3,204,512 | $ 3,084,451
Assumed | 22,664 | 24,288 | 24,339
Ceded premiums written | (489,488) | (455,708) | (429,366)
Net | 3,189,713 | 2,773,092 | 2,679,424
Direct premiums written | 3,656,537 | 3,204,512 | 3,084,451
Premiums Earned: |  |  |
Direct | 3,472,715 | 3,108,687 | 2,993,157
Assumed | 21,550 | 25,010 | 24,399
Ceded premiums earned | (477,012) | (451,883) | (420,385)
Total Net Premiums Earned | 3,017,253 | 2,681,814 | 2,597,171
Loss and loss expense incurred: |  |  |
Direct | 2,096,512 | 1,822,034 | 1,714,880
Assumed | 13,813 | 17,201 | 22,879
Ceded loss and loss expense | (296,341) | (203,412) | (186,268)
Net | $ 1,813,984 | $ 1,635,823 | $ 1,551,491
Increase in DPW from Prior Year | 14.00% | 4.00% |
Return audit and midterm endorsement premium [Member] | COVID-19 [Member] |  |  |
Premiums Written: |  |  |
Direct premiums written | $ 75,000 |  |
Direct premiums written | 75,000 |  |
Commercial & Personal Automobile [Member] | COVID-19 [Member] |  |  |
Premiums Written: |  |  |
Direct premiums written | 19,700 |  |
Direct premiums written | $ 19,700 |  |

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