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v3.19.3.a.u2

Reinsurance (Consolidated Reinsurance) (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
Premiums written [Abstract] |  |  |  |  |  |  |  |  |  |  |
Direct |  |  |  |  |  |  |  |  | $ 36,848 | $ 34,782 | $ 33,137
Assumed |  |  |  |  |  |  |  |  | 3,276 | 3,186 | 3,239
Ceded |  |  |  |  |  |  |  |  | (7,849) | (7,389) | (7,132)
Net |  |  |  |  |  |  |  |  | 32,275 | 30,579 | 29,244
Premiums earned [Abstract] |  |  |  |  |  |  |  |  |  |  |
Direct |  |  |  |  |  |  |  |  | 35,876 | 34,108 | 32,782
Assumed |  |  |  |  |  |  |  |  | 3,107 | 3,175 | 3,332
Ceded |  |  |  |  |  |  |  |  | (7,693) | (7,219) | (7,080)
Net premiums earned | $ 7,935 | $ 8,327 | $ 7,891 | $ 7,137 | $ 7,465 | $ 7,908 | $ 7,664 | $ 7,027 | 31,290 | 30,064 | 29,034
Reinsurance recoveries on losses and loss expenses incurred |  |  |  |  |  |  |  |  | $ 4,900 | $ 5,600 | $ 5,500

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