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v3.19.3.a.u2

Reserve for Loss and Loss Expense (Reconciliation of Claims Development to Liability) (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Net outstanding liabilities | $ 1,551,491 | $ 1,498,134 | $ 1,345,074 |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 3,392,713 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 544,162 | 537,388 | 585,855 | $ 611,200
Short-duration Insurance Contracts, Liability for Unpaid Claims and Claims Adjustment Expense, Accumulated Unallocated Claim Adjustment Expense | 130,288 |  |  |
Liability for Claims and Claims Adjustment Expense | 4,067,163 | $ 3,893,868 | $ 3,771,240 | $ 3,691,719
General Liability [Member] | Standard Commercial Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 1,280,416 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 195,830 |  |  |
General Liability [Member] | E&S Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 365,943 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 14,319 |  |  |
Workers Compensation [Member] | Standard Commercial Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 850,505 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 206,414 |  |  |
Commercial Automobile [Member] | Standard Commercial Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 596,686 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 14,352 |  |  |
Business Owners' Policies [Member] | Standard Commercial Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 86,747 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 3,012 |  |  |
Commercial Property [Member] | Standard Commercial Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 52,071 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 26,526 |  |  |
Commercial Property [Member] | E&S Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 8,199 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 317 |  |  |
Other Commercial [Member] | Standard Commercial Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 9,399 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 9,113 |  |  |
Total Standard Commercial Lines [Member] | Standard Commercial Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 2,875,824 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 455,247 |  |  |
Personal Automobile [Member] | Standard Personal Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 100,331 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 44,104 |  |  |
Homeowners [Member] | Standard Personal Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 31,752 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 1,182 |  |  |
Other Personal [Member] | Standard Personal Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 10,664 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 28,993 |  |  |
Standard Personal Lines [Member] | Standard Personal Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 142,747 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 74,279 |  |  |
Total E&S Lines [Member] | E&S Lines [Member] |  |  |  |
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items] |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 374,142 |  |  |
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | $ 14,636 |  |  |

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