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Loss And Loss Adjustment Expense Reserves (Narrative) (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended | 7 Months Ended | 9 Months Ended
--- | --- | --- | --- | --- | ---
Jan. 31, 2018 | Jun. 30, 2019 | Dec. 31, 2018 | Jul. 31, 2018 | Sep. 30, 2020 | Sep. 30, 2019
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |
Prior year claims and claims adjustment expense |  |  |  |  | $ 25,511 | $ 10,323
Adjustments for prior year claims |  |  |  |  | 786,180 | 715,451
Loss from catastrophes |  |  |  |  | 43,000 | 17,000
Credit Agreement [Member] | LIBOR [Member] | FFL [Member] |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 1.28% |  | 1.05% | 1.20% |  |
Catastrophe [Member] |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |
Adjustments for prior year claims |  |  |  |  | 5,000 | 3,000
Liability for catastrophe claims, carrying amount |  |  |  |  | $ 48,000 |
Loss from catastrophes |  |  |  |  |  | $ 20,000
Fire [Member] |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |
Loss from catastrophes, net of reinsurance benefits |  | $ 40,000 |  |  |  |
Liability for catastrophe claims, carrying amount |  | 208,000 |  |  |  |
Benefit from sale of subrogation rights |  | $ 10,000 |  |  |  |

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- Definition The amount of estimated liability as of the balance sheet date for the specific conflagration, earthquake, windstorm, explosion, or similar event. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
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- Definition Amount, after effects of reinsurance, of payments to settle claims incurred in prior periods and related claims settlement costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
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- Definition The charge against earnings in the period for the uninsured portion of a loss from a fire, explosion, or natural disaster (hurricane, earthquake). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.9) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 + Details
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- Definition The estimated amount as of the balance sheet date to be received by an insurer from the sale of property (usually damaged) on which the insurer has paid a total claim to the insured and has obtained title to the property and the right of an insurer to pursue any course of recovery of damages, in its name or in the name of the policyholder, against a third party who is liable for costs relating to an insured event that have been paid by the insurer. Estimated salvage and subrogation is generally deducted from the liability for unpaid claims. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 30 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6482241&loc=d3e13783-158432 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 30 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6482241&loc=d3e13779-158432 + Details
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