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Insurance Premiums (Unearned Premium Revenue Balance And Future Expected Earnings) (Detail) $ in Millions | Dec. 31, 2022 USD ($)
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Insurance Premiums [Line Items] |
Total Expected Future Premium Earnings | $ 310
March Thirty One Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2023, Total Expected Future Premium Earnings | 9
June Thirty Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, June 30, 2023, Total Expected Future Premium Earnings | 9
September Thirty Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, September 30, 2023, Total Expected Future Premium Earnings | 9
December Thirty One Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, December 31, 2023, Total Expected Future Premium Earnings | 9
December Thirty One Two Thousand Twenty Four [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2024, Total Expected Future Premium Earnings | 33
December Thirty One Two Thousand Twenty Five [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2025, Total Expected Future Premium Earnings | 29
December Thirty One Two Thousand Twenty Six [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2026, Total Expected Future Premium Earnings | 25
December Thirty One Two Thousand Twenty Seven [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2027, Total Expected Future Premium Earnings | 22
December Thirty One Two Thousand Twenty Thirty Two [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2032, Total Expected Future Premium Earnings | 79
December Thirty One Two Thousand Twenty Thirty Seven [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2037, Total Expected Future Premium Earnings | 46
December Thirty One Two Thousand Fourty Two And Thereafter [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2042 and thereafter, Total Expected Future Premium Earnings | 40
Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 266
Unearned Premium Revenue [Member] | March Thirty One Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2023, Total Expected Future Premium Earnings | 258
Unearned Premium Revenue [Member] | June Thirty Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, June 30, 2023, Total Expected Future Premium Earnings | 250
Unearned Premium Revenue [Member] | September Thirty Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, September 30, 2023, Total Expected Future Premium Earnings | 242
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, December 31, 2023, Total Expected Future Premium Earnings | 234
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Twenty Four [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2024, Total Expected Future Premium Earnings | 205
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Twenty Five [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2025, Total Expected Future Premium Earnings | 180
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Twenty Six [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2026, Total Expected Future Premium Earnings | 158
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Twenty Seven [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2027, Total Expected Future Premium Earnings | 139
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Twenty Thirty Two [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2032, Total Expected Future Premium Earnings | 73
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Twenty Thirty Seven [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2037, Total Expected Future Premium Earnings | 35
Unearned Premium Revenue [Member] | December Thirty One Two Thousand Fourty Two And Thereafter [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2042 and thereafter, Total Expected Future Premium Earnings | 0
Upfront [Member] |
Insurance Premiums [Line Items] |
Total Expected Future Premium Earnings | 119
Upfront [Member] | March Thirty One Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2023, Total Expected Future Premium Earnings | 4
Upfront [Member] | June Thirty Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, June 30, 2023, Total Expected Future Premium Earnings | 4
Upfront [Member] | September Thirty Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, September 30, 2023, Total Expected Future Premium Earnings | 4
Upfront [Member] | December Thirty One Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, December 31, 2023, Total Expected Future Premium Earnings | 4
Upfront [Member] | December Thirty One Two Thousand Twenty Four [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2024, Total Expected Future Premium Earnings | 14
Upfront [Member] | December Thirty One Two Thousand Twenty Five [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2025, Total Expected Future Premium Earnings | 13
Upfront [Member] | December Thirty One Two Thousand Twenty Six [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2026, Total Expected Future Premium Earnings | 11
Upfront [Member] | December Thirty One Two Thousand Twenty Seven [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2027, Total Expected Future Premium Earnings | 10
Upfront [Member] | December Thirty One Two Thousand Twenty Thirty Two [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2032, Total Expected Future Premium Earnings | 31
Upfront [Member] | December Thirty One Two Thousand Twenty Thirty Seven [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2037, Total Expected Future Premium Earnings | 14
Upfront [Member] | December Thirty One Two Thousand Fourty Two And Thereafter [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2042 and thereafter, Total Expected Future Premium Earnings | 10
Installments [Member] |
Insurance Premiums [Line Items] |
Total Expected Future Premium Earnings | 147
Installments [Member] | March Thirty One Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2023, Total Expected Future Premium Earnings | 4
Installments [Member] | June Thirty Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, June 30, 2023, Total Expected Future Premium Earnings | 4
Installments [Member] | September Thirty Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, September 30, 2023, Total Expected Future Premium Earnings | 4
Installments [Member] | December Thirty One Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, December 31, 2023, Total Expected Future Premium Earnings | 4
Installments [Member] | December Thirty One Two Thousand Twenty Four [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2024, Total Expected Future Premium Earnings | 15
Installments [Member] | December Thirty One Two Thousand Twenty Five [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2025, Total Expected Future Premium Earnings | 12
Installments [Member] | December Thirty One Two Thousand Twenty Six [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2026, Total Expected Future Premium Earnings | 11
Installments [Member] | December Thirty One Two Thousand Twenty Seven [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2027, Total Expected Future Premium Earnings | 9
Installments [Member] | December Thirty One Two Thousand Twenty Thirty Two [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2032, Total Expected Future Premium Earnings | 35
Installments [Member] | December Thirty One Two Thousand Twenty Thirty Seven [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2037, Total Expected Future Premium Earnings | 24
Installments [Member] | December Thirty One Two Thousand Fourty Two And Thereafter [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2042 and thereafter, Total Expected Future Premium Earnings | 25
Accretion [Member] |
Insurance Premiums [Line Items] |
Total Expected Future Premium Earnings | 44
Accretion [Member] | March Thirty One Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2023, Total Expected Future Premium Earnings | 1
Accretion [Member] | June Thirty Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, June 30, 2023, Total Expected Future Premium Earnings | 1
Accretion [Member] | September Thirty Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, September 30, 2023, Total Expected Future Premium Earnings | 1
Accretion [Member] | December Thirty One Two Thousand Twenty Three [Member] |
Insurance Premiums [Line Items] |
Three months ending, December 31, 2023, Total Expected Future Premium Earnings | 1
Accretion [Member] | December Thirty One Two Thousand Twenty Four [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2024, Total Expected Future Premium Earnings | 4
Accretion [Member] | December Thirty One Two Thousand Twenty Five [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2025, Total Expected Future Premium Earnings | 4
Accretion [Member] | December Thirty One Two Thousand Twenty Six [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2026, Total Expected Future Premium Earnings | 3
Accretion [Member] | December Thirty One Two Thousand Twenty Seven [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2027, Total Expected Future Premium Earnings | 3
Accretion [Member] | December Thirty One Two Thousand Twenty Thirty Two [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2032, Total Expected Future Premium Earnings | 13
Accretion [Member] | December Thirty One Two Thousand Twenty Thirty Seven [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2037, Total Expected Future Premium Earnings | 8
Accretion [Member] | December Thirty One Two Thousand Fourty Two And Thereafter [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2042 and thereafter, Total Expected Future Premium Earnings | $ 5

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- Definition Financial guarantee insurance contracts, the amount of premium revenue expected to be recognized during the eleventh through fifteenth year 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 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 contract to be recognized in next fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in fourth fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in second fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in third fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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