| **Business Segments (Tables)**                                                                 | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        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| **Segment Reporting [Abstract]**                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         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| Significant components of the Company's continuing operations and selected balance sheet items | Three months ended June 30, 2013CNASpecialty CNACommercial Hardy Life &GroupNon-Core Corporate& OtherNon-Core    (In millions)     Eliminations TotalOperating revenues             Net earned premiums$746 $840 $76 $138 $— $— $1,800Net investment income151 211 1 207 8 — 578Other revenues63 65 (1) 1 2 (1) 129Total operating revenues960 1,116 76 346 10 (1) 2,507Claims, Benefits and Expenses             Net incurred claims and benefits452 644 41 380 (2) — 1,515Policyholders’ dividends1 2 — 3 — — 6Amortization of deferred acquisition costs156 153 20 6 — — 335Other insurance related expenses65 142 13 33 — — 253Other expenses60 2 6 2 39 (1) 108Total claims, benefits and expenses734 943 80 424 37 (1) 2,217Operating income (loss) before income tax226 173 (4) (78) (27) — 290Income tax (expense) benefit on operating income (loss)(78) (61) 2 42 9 — (86)Net operating income (loss)148 112 (2) (36) (18) — 204Net realized investment gains (losses), pre-tax(6) (12) 1 — 3 — (14)Income tax (expense) benefit on net realized investment gains (losses)2 4 (1) — (1) — 4Net realized investment gains (losses)(4) (8) — — 2 — (10)Net income (loss)$144 $104 $(2) $(36) $(16) $— $194Three months ended June 30, 2012CNASpecialty CNACommercial Hardy Life &GroupNon-Core Corporate& OtherNon-Core    (In millions)     Eliminations TotalOperating revenues             Net earned premiums$719 $809  $139 $2 $(1) $1,668Net investment income112 151  201 6 — 470Other revenues57 11  16 2 — 86Total operating revenues888 971  356 10 (1) 2,224Claims, Benefits and Expenses             Net incurred claims and benefits448 591  323 (20) — 1,342Policyholders’ dividends1 3  2 — — 6Amortization of deferred acquisition costs154 147  8 — — 309Other insurance related expenses77 135  36 1 (1) 248Other expenses50 10  4 47 — 111Total claims, benefits and expenses730 886  373 28 (1) 2,016Operating income (loss) before income tax158 85  (17) (18) — 208Income tax (expense) benefit on operating income (loss)(52) (28)  20 4 — (56)Net operating income (loss)106 57  3 (14) — 152Net realized investment gains (losses), pre-tax8 13  4 (3) — 22Income tax (expense) benefit on net realized investment gains (losses)(2) (5)  (1) — — (8)Net realized investment gains (losses)6 8  3 (3) — 14Net income (loss)$112 $65  $6 $(17) $— $166Six months ended June 30, 2013CNASpecialty CNACommercial Hardy Life &GroupNon-Core Corporate& OtherNon-Core    (In millions)     Eliminations TotalOperating revenues             Net earned premiums$1,469 $1,677 $140 $279 $— $(1) $3,564Net investment income321 461 2 411 16 — 1,211Other revenues123 75 — 5 5 (1) 207Total operating revenues1,913 2,213 142 695 21 (2) 4,982Claims, Benefits and Expenses             Net incurred claims and benefits917 1,244 72 705 2 — 2,940Policyholders’ dividends2 4 — 4 — — 10Amortization of deferred acquisition costs306 302 41 14 — — 663Other insurance related expenses136 285 29 66 — (1) 515Other expenses114 11 13 7 85 (1) 229Total claims, benefits and expenses1,475 1,846 155 796 87 (2) 4,357Operating income (loss) before income tax438 367 (13) (101) (66) — 625Income tax (expense) benefit on operating income (loss)(150) (130) 3 65 22 — (190)Net operating income (loss)288 237 (10) (36) (44) — 435Net realized investment gains (losses), pre-tax(3) (8) 2 14 9 — 14Income tax (expense) benefit on net realized investment gains (losses)1 3 (1) (5) (3) — (5)Net realized investment gains (losses)(2) (5) 1 9 6 — 9Net income (loss)$286 $232 $(9) $(27) $(38) $— $444June 30, 2013             (In millions)             Reinsurance receivables$698 $1,146 $235 $1,258 $2,704 $— $6,041Insurance receivables$786 $1,219 $208 $11 $3 $— $2,227Deferred acquisition costs$317 $277 $56 $— $— $— $650Goodwill$117 $— $35 $— $— $— $152Insurance reserves             Claim and claim adjustment expenses$6,877 $10,973 $447 $3,031 $3,011 $— $24,339Unearned premiums1,787 1,682 265 136 — (1) 3,869Future policy benefits— — — 10,787 — — 10,787Policyholders’ funds9 14 — 110 — — 133Six months ended June 30, 2012CNASpecialty CNACommercial Hardy Life &GroupNon-Core Corporate& OtherNon-Core    (In millions)     Eliminations TotalOperating revenues             Net earned premiums$1,425 $1,612  $280 $1 $(1) $3,317Net investment income287 416  399 16 — 1,118Other revenues113 20  14 7 — 154Total operating revenues1,825 2,048  693 24 (1) 4,589Claims, Benefits and Expenses             Net incurred claims and benefits916 1,158  659 (13) — 2,720Policyholders’ dividends(1) 6  4 — — 9Amortization of deferred acquisition costs302 286  16 — — 604Other insurance related expenses149 279  71 — (1) 498Other expenses100 17  10 95 — 222Total claims, benefits and expenses1,466 1,746   760 82 (1) 4,053Operating income (loss) before income tax359 302  (67) (58) — 536Income tax (expense) benefit on operating income (loss)(121) (106)  51 18 — (158)Net operating income (loss)238 196  (16) (40) — 378Net realized investment gains (losses), pre-tax16 24  17 1 — 58Income tax (expense) benefit on net realized investment gains (losses)(4) (9)  (6) (1) — (20)Net realized investment gains (losses)12 15  11 — — 38Net income (loss)$250 $211  $(5) $(40) $— $416December 31, 2012             (In millions)             Reinsurance receivables$665 $1,155 $294 $1,273 $2,844 $— $6,231Insurance receivables$673 $1,116 $181 $9 $4 $— $1,983Deferred acquisition costs$300 $269 $29 $— $— $— $598Goodwill$117 $— $37 $— $— $— $154Insurance reserves             Claim and claim adjustment expenses$6,748 $11,326 $521 $3,006 $3,162 $— $24,763Unearned premiums1,685 1,569 222 134 — — 3,610Future policy benefits— — — 11,475 — — 11,475Policyholders’ funds8 15 — 134 — — 157 |
| Revenues by line of business                                                                   | Revenues by Line of BusinessPeriods ended June 30Three Months Six Months(In millions)2013 2012 2013 2012CNA Specialty       International$59 $53 $118 $110Professional & Management Liability687 645 1,387 1,339Surety123 121 239 240Warranty & Alternative Risks85 77 166 152CNA Specialty revenues954 896 1,910 1,841CNA Commercial       Commercial Insurance827 736 1,653 1,571International90 90 183 181Small Business187 158 369 320CNA Commercial revenues1,104 984 2,205 2,072Hardy revenues77   144  Life & Group Non-Core       Health287 287 585 578Life & Annuity58 57 119 117Other1 16 5 15Life & Group Non-Core revenues346 360 709 710Corporate & Other Non-Core revenues13 7 30 25Eliminations(1) (1) (2) (1)Total revenues$2,493 $2,246 $4,996 $4,647                                                                                                                                                                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| - Definition
Tabular disclosure of all significant reconciling items in the reconciliation of total revenues from reportable segments to the entity's consolidated revenues.
+ References
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| - Definition
Tabular disclosure of the profit or loss and total assets for each reportable segment. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.
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