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Loss And Loss Adjustment Expense Reserves - Average Annual Percentage Payout of Incurred Claims by Age (Details) | Dec. 31, 2018
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Property insurance product line, automobile [Member] |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Short-duration insurance contracts, historical claims duration, year one | 64.70%
Short-duration insurance contracts, historical claims duration, year two | 17.30%
Short-duration insurance contracts, historical claims duration, year three | 8.70%
Short-duration insurance contracts, historical claims duration, year four | 5.00%
Short-duration insurance contracts, historical claims duration, year five | 2.50%
Short-duration insurance contracts, historical claims duration, year six | 0.80%
Short-duration insurance contracts, historical claims duration, year seven | 0.60%
Short-duration insurance contracts, historical claims duration, year eight | 0.30%
Short-duration insurance contracts, historical claims duration, year nine | 0.10%
Short-duration insurance contracts, historical claims duration, year ten | 0.00%
Property insurance product line, homeowners' [Member] |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Short-duration insurance contracts, historical claims duration, year one | 67.30%
Short-duration insurance contracts, historical claims duration, year two | 23.00%
Short-duration insurance contracts, historical claims duration, year three | 4.70%
Short-duration insurance contracts, historical claims duration, year four | 2.60%
Short-duration insurance contracts, historical claims duration, year five | 1.10%
Short-duration insurance contracts, historical claims duration, year six | 0.70%
Short-duration insurance contracts, historical claims duration, year seven | 0.30%
Short-duration insurance contracts, historical claims duration, year eight | 0.20%
Short-duration insurance contracts, historical claims duration, year nine | 0.10%
Short-duration insurance contracts, historical claims duration, year ten | 0.00%

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- Definition Percentage of average annual payout, after reinsurance, in the eighth year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4G -URI http://asc.fasb.org/extlink&oid=99384497&loc=SL65671329-158438 + Details
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- Definition Percentage of average annual 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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4G -URI http://asc.fasb.org/extlink&oid=99384497&loc=SL65671329-158438 + Details
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- Definition Percentage of average annual 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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4G -URI http://asc.fasb.org/extlink&oid=99384497&loc=SL65671329-158438 + Details
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- Definition Percentage of average annual 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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4G -URI http://asc.fasb.org/extlink&oid=99384497&loc=SL65671329-158438 + 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4G -URI http://asc.fasb.org/extlink&oid=99384497&loc=SL65671329-158438 + Details
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- Definition Percentage of average annual payout, after reinsurance, in the seventh year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4G -URI http://asc.fasb.org/extlink&oid=99384497&loc=SL65671329-158438 + Details
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- Definition Percentage of average annual 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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4G -URI http://asc.fasb.org/extlink&oid=99384497&loc=SL65671329-158438 + Details
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