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Insurance Premiums (Unearned Premium Revenue Balance And Future Expected Earnings) (Detail) $ in Millions | Dec. 31, 2017 USD ($)
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Insurance Premiums [Line Items] |
Three months ending, March 31, 2018, Total Expected Future Premium Earnings | $ 25
Three months ending, June 30, 2018, Total Expected Future Premium Earnings | 24
Three months ending, September 30, 2018, Total Expected Future Premium Earnings | 23
Three months ending, December 31, 2018, Total Expected Future Premium Earnings | 23
Twelve months ending, December 31, 2019, Total Expected Future Premium Earnings | 87
Twelve months ending, December 31, 2020, Total Expected Future Premium Earnings | 79
Twelve months ending, December 31, 2021, Total Expected Future Premium Earnings | 71
Twelve months ending, December 31, 2022, Total Expected Future Premium Earnings | 64
Five years ending, December 31, 2027, Total Expected Future Premium Earnings | 225
Five years ending, December 31, 2032, Total Expected Future Premium Earnings | 115
Five years ending, December 31, 2037 and thereafter, Total Expected Future Premium Earnings | 107
Total Expected Future Premium Earnings | 843
Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 752
Unearned Premium Revenue [Member] | March Thirty One Two Thousand Eighteen [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 729
Unearned Premium Revenue [Member] | June Thirty Two Thousand Eighteen [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 707
Unearned Premium Revenue [Member] | September Thirty Two Thousand Eighteen [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 686
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Eighteen [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 665
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Nineteen [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 587
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Twenty [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 516
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Twenty One [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 452
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Twenty Two [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 395
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Twenty Seven [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 195
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Thirty Two [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 94
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Thirty Seven And Thereafter [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 0
Upfront [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2018, Total Expected Future Premium Earnings | 12
Three months ending, June 30, 2018, Total Expected Future Premium Earnings | 12
Three months ending, September 30, 2018, Total Expected Future Premium Earnings | 11
Three months ending, December 31, 2018, Total Expected Future Premium Earnings | 11
Twelve months ending, December 31, 2019, Total Expected Future Premium Earnings | 41
Twelve months ending, December 31, 2020, Total Expected Future Premium Earnings | 37
Twelve months ending, December 31, 2021, Total Expected Future Premium Earnings | 33
Twelve months ending, December 31, 2022, Total Expected Future Premium Earnings | 30
Five years ending, December 31, 2027, Total Expected Future Premium Earnings | 105
Five years ending, December 31, 2032, Total Expected Future Premium Earnings | 54
Five years ending, December 31, 2037 and thereafter, Total Expected Future Premium Earnings | 40
Total Expected Future Premium Earnings | 386
Installments [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2018, Total Expected Future Premium Earnings | 11
Three months ending, June 30, 2018, Total Expected Future Premium Earnings | 10
Three months ending, September 30, 2018, Total Expected Future Premium Earnings | 10
Three months ending, December 31, 2018, Total Expected Future Premium Earnings | 10
Twelve months ending, December 31, 2019, Total Expected Future Premium Earnings | 37
Twelve months ending, December 31, 2020, Total Expected Future Premium Earnings | 34
Twelve months ending, December 31, 2021, Total Expected Future Premium Earnings | 31
Twelve months ending, December 31, 2022, Total Expected Future Premium Earnings | 27
Five years ending, December 31, 2027, Total Expected Future Premium Earnings | 95
Five years ending, December 31, 2032, Total Expected Future Premium Earnings | 47
Five years ending, December 31, 2037 and thereafter, Total Expected Future Premium Earnings | 54
Total Expected Future Premium Earnings | 366
Accretion [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2018, Total Expected Future Premium Earnings | 2
Three months ending, June 30, 2018, Total Expected Future Premium Earnings | 2
Three months ending, September 30, 2018, Total Expected Future Premium Earnings | 2
Three months ending, December 31, 2018, Total Expected Future Premium Earnings | 2
Twelve months ending, December 31, 2019, Total Expected Future Premium Earnings | 9
Twelve months ending, December 31, 2020, Total Expected Future Premium Earnings | 8
Twelve months ending, December 31, 2021, Total Expected Future Premium Earnings | 7
Twelve months ending, December 31, 2022, Total Expected Future Premium Earnings | 7
Five years ending, December 31, 2027, Total Expected Future Premium Earnings | 25
Five years ending, December 31, 2032, Total Expected Future Premium Earnings | 14
Five years ending, December 31, 2037 and thereafter, Total Expected Future Premium Earnings | 13
Total Expected Future Premium Earnings | $ 91

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- Definition Financial guarantee insurance contracts, the amount of premium revenue expected to be recognized during the sixteenth year and thereafter following the statement of financial position reporting date. + References No definition available. + Details
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- Definition Financial guarantee insurance contracts, the amount of premium revenue expected to be recognized during the sixth through tenth year following the statement of financial position reporting date + References No definition available. + Details
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- Definition Amount of unearned premium revenue under contracts issued by an insurance entity that provide protection to the holder of a financial obligation from a financial loss in the event of a default. + References No definition available. + Details
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- Definition Amount of premium revenue under financial guarantee insurance contracts expected to be recognized in the next fiscal quarter following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contracts expected to be recognized in the fourth fiscal quarter following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contracts expected to be recognized in the second fiscal quarter following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contracts expected to be recognized in the third fiscal quarter following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contracts expected to be recognized in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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