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Claim and Claim Adjustment Expense Reserves - Net Prior Year Development in CNA's Property and Casualty Operations (Detail) - CNA Financial [Member] - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |  |
Medical professional liability | $ 15 | $ 3 | $ 30 | $ 23
Other professional liability and management liability | (7) | (34) | (19) | (68)
Surety | (15) | (15) | (40) | (30)
Commercial auto | (3) |  | (8) | (1)
General liability | 13 | 26 | (7) | 18
Workers' compensation | (7) | (6) | (5) | (12)
Other | (27) | (33) | 4 | (28)
Total pretax (favorable) unfavorable development | $ (31) | $ (59) | $ (45) | $ (98)

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- Definition Net prior year claim and allocated claim adjustment. + References No definition available. + Details
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- Definition Net Prior Year Claim and Allocated Claim Adjustment Expense, Medical Professional Liability + References No definition available. + Details
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- Definition Net Prior Year Claim And Allocated Claim Adjustment Expense Other Professional Liability And Management Liability + References No definition available. + Details
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- Definition Net prior year claim and allocated claim adjustment expense, surety. + References No definition available. + Details
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- Definition Net Prior Year Claim and Allocated Claim Adjustment, General Liability + References No definition available. + Details
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- Definition Net Prior Year Claim and Allocated Claim Adjustment, Workers Compensation + References No definition available. + Details
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- Definition Pretax favorable unfavorable net prior year claim and allocated claim adjustment expense reserve development excluding life group. + References No definition available. + Details
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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. + References No definition available. + Details
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- Details
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