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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
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Mar. 31, 2019 | Mar. 31, 2018
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |
Medical professional liability | $ 15 | $ 20
Other professional liability and management liability | (12) | (34)
Surety | (25) | (15)
Commercial auto | (5) | (1)
General liability | (20) | (8)
Workers' compensation | 2 | (6)
Property and other | 31 | 5
Total pretax (favorable) unfavorable development | $ (14) | $ (39)

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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, Property and Other. + 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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