Condensed Unaudited Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||
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Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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Condensed Income Statements, Captions [Line Items] | |||||||||||
Income tax benefit related to 2017 Tax Act | $ (450) | $ 0 | $ 0 | ||||||||
Net premiums earned | $ 7,218 | $ 7,807 | $ 7,237 | $ 6,772 | $ 7,059 | $ 7,688 | $ 7,405 | $ 6,597 | 29,034 | 28,749 | 17,213 |
Net Investment Income | 797 | 813 | 770 | 745 | 744 | 739 | 708 | 674 | 3,125 | 2,865 | 2,194 |
Net realized gains (losses) including OTTI | 0 | (10) | 101 | (7) | 365 | 100 | (216) | (394) | 84 | (145) | (420) |
Total revenues | 8,015 | 8,610 | 8,108 | 7,510 | 8,168 | 8,527 | 7,897 | 6,877 | 32,243 | 31,469 | 18,987 |
Losses and loss expenses | 4,272 | 6,247 | 4,146 | 3,789 | 3,855 | 4,269 | 4,254 | 3,674 | 18,454 | 16,052 | 9,484 |
Policy benefits | 176 | 169 | 163 | 168 | 161 | 155 | 146 | 126 | 676 | 588 | 543 |
Net income | $ 1,533 | $ (70) | $ 1,305 | $ 1,093 | $ 1,610 | $ 1,360 | $ 726 | $ 439 | $ 3,861 | $ 4,135 | $ 2,834 |
Basic earnings per share | $ 3.29 | $ (0.15) | $ 2.79 | $ 2.33 | $ 3.44 | $ 2.90 | $ 1.55 | $ 0.98 | $ 8.26 | $ 8.94 | $ 8.71 |
Diluted earnings per share | $ 3.27 | $ (0.15) | $ 2.77 | $ 2.31 | $ 3.41 | $ 2.88 | $ 1.54 | $ 0.97 | $ 8.19 | $ 8.87 | $ 8.62 |
Loss from Catastrophes | $ 1,500 |
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- Definition Income tax benefit related to 2017 Tax Act No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of expense (income) recognized due to changes in the accrued obligation to policyholders that relates to insured events. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The charge against earnings in the period for the uninsured portion of a loss from a fire, explosion, or natural disaster (hurricane, earthquake). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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