| **Business Segments (Tables)**                                                                 | 9 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 September 30, 2013CNASpecialty CNACommercial Hardy Life &GroupNon-Core Corporate& OtherNon-Core    (In millions)     Eliminations TotalOperating revenues             Net earned premiums$768 $832 $86 $140 $— $(1) $1,825Net investment income159 219 1 209 9 — 597Other revenues67 10 1 (3) 3 — 78Total operating revenues994 1,061 88 346 12 (1) 2,500Claims, Benefits and Expenses             Net incurred claims and benefits427 565 35 377 4 — 1,408Policyholders’ dividends3 1 — 2 — — 6Amortization of deferred acquisition costs161 148 25 7 — — 341Other insurance related expenses64 141 14 34 1 (1) 253Other expenses58 7 2 5 49 — 121Total claims, benefits and expenses713 862 76 425 54 (1) 2,129Operating income (loss) before income tax281 199 12 (79) (42) — 371Income tax (expense) benefit on operating income (loss)(94) (68) — 44 16 — (102)Net operating income (loss)187 131 12 (35) (26) — 269Net realized investment gains (losses), pre-tax2 1 — — 1 — 4Income tax (expense) benefit on net realized investment gains (losses)(1) — 1 — (1) — (1)Net realized investment gains (losses)1 1 1 — — — 3Net income (loss)$188 $132 $13 $(35) $(26) $— $272Three months ended September 30, 2012CNASpecialty CNACommercial Hardy Life &GroupNon-Core Corporate& OtherNon-Core    (In millions)     Eliminations TotalOperating revenues             Net earned premiums$738 $840 $64 $141 $(2) $— $1,781Net investment income159 230 2 201 9 — 601Other revenues58 11 — 1 7 (1) 76Total operating revenues955 1,081 66 343 14 (1) 2,458Claims, Benefits and Expenses             Net incurred claims and benefits460 591 21 350 8 — 1,430Policyholders’ dividends1 3 — 1 — — 5Amortization of deferred acquisition costs156 151 20 6 — — 333Other insurance related expenses73 146 13 35 1 — 268Other expenses53 7 7 8 42 (1) 116Total claims, benefits and expenses743 898 61 400 51 (1) 2,152Operating income (loss) before income tax212 183 5 (57) (37) — 306Income tax (expense) benefit on operating income (loss)(76) (58) (2) 35 11 — (90)Net operating income (loss)136 125 3 (22) (26) — 216Net realized investment gains (losses), pre-tax2 10 (1) (3) — — 8Income tax (expense) benefit on net realized investment gains (losses)(2) (3) — 1 1 — (3)Net realized investment gains (losses)— 7 (1) (2) 1 — 5Net income (loss)$136 $132 $2 $(24) $(25) $— $221Nine months ended September 30, 2013CNASpecialty CNACommercial Hardy Life &GroupNon-Core Corporate& OtherNon-Core    (In millions)     Eliminations TotalOperating revenues             Net earned premiums$2,237 $2,509 $226 $419 $— $(2) $5,389Net investment income480 680 3 620 25 — 1,808Other revenues190 85 1 2 8 (1) 285Total operating revenues2,907 3,274 230 1,041 33 (3) 7,482Claims, Benefits and Expenses             Net incurred claims and benefits1,344 1,809 107 1,082 6 — 4,348Policyholders’ dividends5 5 — 6 — — 16Amortization of deferred acquisition costs467 450 66 21 — — 1,004Other insurance related expenses200 426 43 100 1 (2) 768Other expenses172 18 15 12 134 (1) 350Total claims, benefits and expenses2,188 2,708 231 1,221 141 (3) 6,486Operating income (loss) before income tax719 566 (1) (180) (108) — 996Income tax (expense) benefit on operating income (loss)(244) (198) 3 109 38 — (292)Net operating income (loss)475 368 2 (71) (70) — 704Net realized investment gains (losses), pre-tax(1) (7) 2 14 10 — 18Income tax (expense) benefit on net realized investment gains (losses)— 3 — (5) (4) — (6)Net realized investment gains (losses)(1) (4) 2 9 6 — 12Net income (loss)$474 $364 $4 $(62) $(64) $— $716September 30, 2013             (In millions)             Reinsurance receivables$613 $1,107 $227 $1,229 $2,627 $— $5,803Insurance receivables$746 $1,112 $211 $10 $4 $— $2,083Deferred acquisition costs$320 $270 $52 $— $— $— $642Goodwill$117 $— $37 $— $— $— $154Insurance reserves             Claim and claim adjustment expenses$6,846 $10,763 $432 $3,050 $2,871 $— $23,962Unearned premiums1,811 1,604 274 132 — (1) 3,820Future policy benefits— — — 10,681 — — 10,681Policyholders’ funds10 15 — 102 — — 127Nine months ended September 30, 2012CNASpecialty CNACommercial Hardy (a) Life &GroupNon-Core Corporate& OtherNon-Core    (In millions)     Eliminations TotalOperating revenues             Net earned premiums$2,163 $2,452 $64 $421 $(1) $(1) $5,098Net investment income446 646 2 600 25 — 1,719Other revenues171 31 — 15 14 (1) 230Total operating revenues2,780 3,129 66 1,036 38 (2) 7,047Claims, Benefits and Expenses             Net incurred claims and benefits1,376 1,749 21 1,009 (5) — 4,150Policyholders’ dividends— 9 — 5 — — 14Amortization of deferred acquisition costs458 437 20 22 — — 937Other insurance related expenses222 425 13 106 1 (1) 766Other expenses153 24 7 18 137 (1) 338Total claims, benefits and expenses2,209 2,644 61 1,160 133 (2) 6,205Operating income (loss) before income tax571 485 5 (124) (95) — 842Income tax (expense) benefit on operating income (loss)(197) (164) (2) 86 29 — (248)Net operating income (loss)374 321 3 (38) (66) — 594Net realized investment gains (losses), pre-tax18 34 (1) 14 1 — 66Income tax (expense) benefit on net realized investment gains (losses)(6) (12) — (5) — — (23)Net realized investment gains (losses)12 22 (1) 9 1 — 43Net income (loss)$386 $343 $2 $(29) $(65) $— $637December 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_______________________________(a)Included from date of acquisition. |
| Revenues by line of business                                                                   | Revenues by Line of BusinessPeriods ended September 30Three Months Nine Months(In millions)2013 2012 2013 2012CNA Specialty       International$59 $53 $177 $163Professional & Management Liability720 700 2,107 2,039Surety126 124 365 364Warranty & Alternative Risks91 80 257 232CNA Specialty revenues996 957 2,906 2,798CNA Commercial       Commercial Insurance776 826 2,429 2,396International93 93 276 274Small Business193 172 562 493CNA Commercial revenues1,062 1,091 3,267 3,163Hardy revenues88 65 232 65Life & Group Non-Core       Health290 274 875 852Life & Annuity58 64 177 181Other(2) 2 3 17Life & Group Non-Core revenues346 340 1,055 1,050Corporate & Other Non-Core revenues13 14 43 39Eliminations(1) (1) (3) (2)Total revenues$2,504 $2,466 $7,500 $7,113                                                                                                                                                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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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