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Insurance - Short-duration insurance contracts, historical claims duration (Details) - Property and casualty insurance | Dec. 31, 2017
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Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance [Line Items] |
Year 1 | 32.70%
Year 2 | 26.10%
Year 3 | 12.10%
Year 4 | 8.50%
Year 5 | 5.30%
Year 6 | 3.30%
Year 7 | 1.80%
Year 8 | 1.20%
Year 9 | 0.80%
Year 10 | 1.00%
Year 1, Cumulative | 32.70%
Year 2, Cumulative | 58.80%
Year 3, Cumulative | 70.90%
Year 4, Cumulative | 79.40%
Year 5, Cumulative | 84.70%
Year 6, Cumulative | 88.00%
Year 7, Cumulative | 89.80%
Year 8, Cumulative | 91.00%
Year 9, Cumulative | 91.80%
Year 10, Cumulative | 92.80%
Property and transportation |
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance [Line Items] |
Year 1 | 45.90%
Year 2 | 29.90%
Year 3 | 8.40%
Year 4 | 6.30%
Year 5 | 3.70%
Year 6 | 1.90%
Year 7 | 0.90%
Year 8 | 0.30%
Year 9 | 0.40%
Year 10 | 0.10%
Year 1, Cumulative | 45.90%
Year 2, Cumulative | 75.80%
Year 3, Cumulative | 84.20%
Year 4, Cumulative | 90.50%
Year 5, Cumulative | 94.20%
Year 6, Cumulative | 96.10%
Year 7, Cumulative | 97.00%
Year 8, Cumulative | 97.30%
Year 9, Cumulative | 97.70%
Year 10, Cumulative | 97.80%
Specialty casualty |
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance [Line Items] |
Year 1 | 18.60%
Year 2 | 23.40%
Year 3 | 16.20%
Year 4 | 11.00%
Year 5 | 6.90%
Year 6 | 4.60%
Year 7 | 2.80%
Year 8 | 2.10%
Year 9 | 1.60%
Year 10 | 1.60%
Year 1, Cumulative | 18.60%
Year 2, Cumulative | 42.00%
Year 3, Cumulative | 58.20%
Year 4, Cumulative | 69.20%
Year 5, Cumulative | 76.10%
Year 6, Cumulative | 80.70%
Year 7, Cumulative | 83.50%
Year 8, Cumulative | 85.60%
Year 9, Cumulative | 87.20%
Year 10, Cumulative | 88.80%
Specialty financial |
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance [Line Items] |
Year 1 | 49.80%
Year 2 | 26.30%
Year 3 | 8.30%
Year 4 | 5.70%
Year 5 | 3.60%
Year 6 | 2.00%
Year 7 | 0.20%
Year 8 | 0.10%
Year 9 | 0.00%
Year 10 | 1.50%
Year 1, Cumulative | 49.80%
Year 2, Cumulative | 76.10%
Year 3, Cumulative | 84.40%
Year 4, Cumulative | 90.10%
Year 5, Cumulative | 93.70%
Year 6, Cumulative | 95.70%
Year 7, Cumulative | 95.90%
Year 8, Cumulative | 96.00%
Year 9, Cumulative | 96.00%
Year 10, Cumulative | 97.50%
Other specialty |
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance [Line Items] |
Year 1 | 19.80%
Year 2 | 17.30%
Year 3 | 12.50%
Year 4 | 12.80%
Year 5 | 8.90%
Year 6 | 5.90%
Year 7 | 3.30%
Year 8 | 2.90%
Year 9 | (0.40%)
Year 10 | 2.30%
Year 1, Cumulative | 19.80%
Year 2, Cumulative | 37.10%
Year 3, Cumulative | 49.60%
Year 4, Cumulative | 62.40%
Year 5, Cumulative | 71.30%
Year 6, Cumulative | 77.20%
Year 7, Cumulative | 80.50%
Year 8, Cumulative | 83.40%
Year 9, Cumulative | 83.00%
Year 10, Cumulative | 85.30%

X
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- Definition Percentage on a cumulative basis of average payout, after reinsurance, in the fifth year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts. + References No definition available. + Details
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- Definition Percentage on a cumulative basis of average payout, after reinsurance, in the fourth year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts. + References No definition available. + Details
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- Definition Percentage on a cumulative basis of average payout, after reinsurance, in the ninth year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts. + References No definition available. + Details
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- Definition Percentage on a cumulative basis of average payout, after reinsurance, in the tenth year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts. + References No definition available. + Details
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- Definition Percentage of average annual payout, after reinsurance, in the first year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4G -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671329-158438 + Details
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