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v3.19.3.a.u2

Related party transaction (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ceded Premiums Written |  |  |  |  |  |  |  |  | $ 7,849 | $ 7,389 | $ 7,132
Losses and loss expenses | $ 4,865 | $ 5,052 | $ 4,715 | $ 4,098 | $ 4,610 | $ 4,868 | $ 4,487 | $ 4,102 | 18,730 | 18,067 | 18,454
Reinsurance recoverable on losses and loss expenses | 15,181 |  |  |  | 15,993 |  |  |  | 15,181 | 15,993 |
Insurance and reinsurance balances payable | 6,184 |  |  |  | 6,437 |  |  |  | 6,184 | 6,437 |
Net premiums written |  |  |  |  |  |  |  |  | 32,275 | 30,579 | 29,244
Starr Technical Risk Agency and Affiliates [Member] |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |
Premiums Written, Gross |  |  |  |  |  |  |  |  | 394 | 411 | 464
Ceded Premiums Written |  |  |  |  |  |  |  |  | 207 | 188 | 175
Paid commissions |  |  |  |  |  |  |  |  | 77 | 84 | 101
Commissions received |  |  |  |  |  |  |  |  | 46 | 42 | 37
Losses and loss expenses |  |  |  |  |  |  |  |  | 185 | 188 | 438
Reinsurance recoverable on losses and loss expenses | 440 |  |  |  | 514 |  |  |  | 440 | 514 |
Insurance and reinsurance balances payable | 56 |  |  |  | 75 |  |  |  | 56 | 75 |
Minimum Amount of Program Business to be Written to Earn Profit Sharing |  |  |  |  |  |  |  |  | 20 |  |
ABR Reinsurance Capital Holdings Ltd. [Member] |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ceded Premiums Written |  |  |  |  |  |  |  |  | 321 | 329 | 342
Commissions received |  |  |  |  |  |  |  |  | 92 | 96 | $ 94
Reinsurance recoverable on losses and loss expenses | 674 |  |  |  | 557 |  |  |  | 674 | 557 |
Insurance and reinsurance balances payable | $ 62 |  |  |  | $ 47 |  |  |  | $ 62 | $ 47 |
Ownership Percentage | 12.20% |  |  |  |  |  |  |  | 12.20% |  |
Warrants & Rights Outstanding | 0.50% |  |  |  |  |  |  |  | 0.50% |  |

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