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Commitments, Guarantees and Contingent Liabilities - Texas Associations (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Loss Contingencies |  |
Liability for claims | $ 26,325,000,000 | $ 25,250,000,000
Texas Windstorm Insurance Association |  |
Loss Contingencies |  |
Issuance of securities to participating insurers upon utilization of funds set aside | $ 1,000,000,000 |
Participation ratio | 13.60% |
Texas Fair Plan Association |  |
Loss Contingencies |  |
Liability for claims | $ 8,000,000 |

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- Definition Represents the value of securities to be issued to participating insurers upon utilization of funds set aside from periods in which premiums exceeded losses. + References No definition available. + Details
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- Definition Represents the participation ratio based upon the entity's proportion of the premiums written. + References No definition available. + Details
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- Definition The amount needed to reflect the estimated ultimate cost of settling claims relating to casualty insurance insured events that have occurred on or before a particular date (ordinarily, the balance sheet date) and the amount needed to provide for the estimated ultimate cost required to investigate and settle claims relating to insured events that have occurred on or before a particular date (ordinarily, the balance sheet date), whether or not reported to the insurer at that date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65670824&loc=d3e14764-158437 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (cc) -URI http://asc.fasb.org/extlink&oid=65670824&loc=d3e14764-158437 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18(Column C)) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + 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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