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Insurance Premiums (Unearned Premium Revenue Balance And Future Expected Earnings) (Detail) $ in Millions | Dec. 31, 2024 USD ($)
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Insurance Premiums [Line Items] |
Total Expected Future Premium Earnings | $ 234
Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Unearned Premiums | 199
Upfront [Member] |
Insurance Premiums [Line Items] |
Total Expected Future Premium Earnings | 83
Installments [Member] |
Insurance Premiums [Line Items] |
Total Expected Future Premium Earnings | 116
Accretion [Member] |
Insurance Premiums [Line Items] |
Total Expected Future Premium Earnings | 35
March Thirty One Two Thousand Twenty Five [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2025, Total Expected Future Premium Earnings | 7
March Thirty One Two Thousand Twenty Five [Member] | Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2025, Total Expected Future Premium Earnings | 193
March Thirty One Two Thousand Twenty Five [Member] | Upfront [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2025, Total Expected Future Premium Earnings | 3
March Thirty One Two Thousand Twenty Five [Member] | Installments [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2025, Total Expected Future Premium Earnings | 3
March Thirty One Two Thousand Twenty Five [Member] | Accretion [Member] |
Insurance Premiums [Line Items] |
Three months ending, March 31, 2025, Total Expected Future Premium Earnings | 1
June Thirty Two Thousand Twenty Five [Member] |
Insurance Premiums [Line Items] |
Three months ending, June 30, 2025, Total Expected Future Premium Earnings | 8
June Thirty Two Thousand Twenty Five [Member] | Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Three months ending, June 30, 2025, Total Expected Future Premium Earnings | 186
June Thirty Two Thousand Twenty Five [Member] | Upfront [Member] |
Insurance Premiums [Line Items] |
Three months ending, June 30, 2025, Total Expected Future Premium Earnings | 3
June Thirty Two Thousand Twenty Five [Member] | Installments [Member] |
Insurance Premiums [Line Items] |
Three months ending, June 30, 2025, Total Expected Future Premium Earnings | 4
June Thirty Two Thousand Twenty Five [Member] | Accretion [Member] |
Insurance Premiums [Line Items] |
Three months ending, June 30, 2025, Total Expected Future Premium Earnings | 1
September Thirty Two Thousand Twenty Five [Member] |
Insurance Premiums [Line Items] |
Three months ending, September 30, 2025, Total Expected Future Premium Earnings | 7
September Thirty Two Thousand Twenty Five [Member] | Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Three months ending, September 30, 2025, Total Expected Future Premium Earnings | 180
September Thirty Two Thousand Twenty Five [Member] | Upfront [Member] |
Insurance Premiums [Line Items] |
Three months ending, September 30, 2025, Total Expected Future Premium Earnings | 3
September Thirty Two Thousand Twenty Five [Member] | Installments [Member] |
Insurance Premiums [Line Items] |
Three months ending, September 30, 2025, Total Expected Future Premium Earnings | 3
September Thirty Two Thousand Twenty Five [Member] | Accretion [Member] |
Insurance Premiums [Line Items] |
Three months ending, September 30, 2025, Total Expected Future Premium Earnings | 1
December Thirty One Two Thousand Twenty Five [Member] |
Insurance Premiums [Line Items] |
Three months ending, December 31, 2025, Total Expected Future Premium Earnings | 7
December Thirty One Two Thousand Twenty Five [Member] | Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Three months ending, December 31, 2025, Total Expected Future Premium Earnings | 174
December Thirty One Two Thousand Twenty Five [Member] | Upfront [Member] |
Insurance Premiums [Line Items] |
Three months ending, December 31, 2025, Total Expected Future Premium Earnings | 3
December Thirty One Two Thousand Twenty Five [Member] | Installments [Member] |
Insurance Premiums [Line Items] |
Three months ending, December 31, 2025, Total Expected Future Premium Earnings | 3
December Thirty One Two Thousand Twenty Five [Member] | Accretion [Member] |
Insurance Premiums [Line Items] |
Three months ending, December 31, 2025, Total Expected Future Premium Earnings | 1
December Thirty One Two Thousand Twenty Six [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2026, Total Expected Future Premium Earnings | 24
December Thirty One Two Thousand Twenty Six [Member] | Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2026, Total Expected Future Premium Earnings | 153
December Thirty One Two Thousand Twenty Six [Member] | Upfront [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2026, Total Expected Future Premium Earnings | 10
December Thirty One Two Thousand Twenty Six [Member] | Installments [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2026, Total Expected Future Premium Earnings | 11
December Thirty One Two Thousand Twenty Six [Member] | Accretion [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2026, Total Expected Future Premium Earnings | 3
December Thirty One Two Thousand Twenty Seven [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2027, Total Expected Future Premium Earnings | 21
December Thirty One Two Thousand Twenty Seven [Member] | Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2027, Total Expected Future Premium Earnings | 135
December Thirty One Two Thousand Twenty Seven [Member] | Upfront [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2027, Total Expected Future Premium Earnings | 9
December Thirty One Two Thousand Twenty Seven [Member] | Installments [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2027, Total Expected Future Premium Earnings | 9
December Thirty One Two Thousand Twenty Seven [Member] | Accretion [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2027, Total Expected Future Premium Earnings | 3
December Thirty One Two Thousand Twenty Eight [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2028, Total Expected Future Premium Earnings | 19
December Thirty One Two Thousand Twenty Eight [Member] | Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2028, Total Expected Future Premium Earnings | 119
December Thirty One Two Thousand Twenty Eight [Member] | Upfront [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2028, Total Expected Future Premium Earnings | 8
December Thirty One Two Thousand Twenty Eight [Member] | Installments [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2028, Total Expected Future Premium Earnings | 8
December Thirty One Two Thousand Twenty Eight [Member] | Accretion [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2028, Total Expected Future Premium Earnings | 3
December Thirty One Two Thousand Twenty Nine [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2029, Total Expected Future Premium Earnings | 17
December Thirty One Two Thousand Twenty Nine [Member] | Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2029, Total Expected Future Premium Earnings | 105
December Thirty One Two Thousand Twenty Nine [Member] | Upfront [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2029, Total Expected Future Premium Earnings | 7
December Thirty One Two Thousand Twenty Nine [Member] | Installments [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2029, Total Expected Future Premium Earnings | 7
December Thirty One Two Thousand Twenty Nine [Member] | Accretion [Member] |
Insurance Premiums [Line Items] |
Twelve months ending, December 31, 2029, Total Expected Future Premium Earnings | 3
December Thirty One Two Thousand Thirty Four [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2039, Total Expected Future Premium Earnings | 61
December Thirty One Two Thousand Thirty Four [Member] | Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2039, Total Expected Future Premium Earnings | 54
December Thirty One Two Thousand Thirty Four [Member] | Upfront [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2039, Total Expected Future Premium Earnings | 21
December Thirty One Two Thousand Thirty Four [Member] | Installments [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2039, Total Expected Future Premium Earnings | 30
December Thirty One Two Thousand Thirty Four [Member] | Accretion [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2039, Total Expected Future Premium Earnings | 10
December Thirty One Two Thousand Thirty Nine [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2034, Total Expected Future Premium Earnings | 35
December Thirty One Two Thousand Thirty Nine [Member] | Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2034, Total Expected Future Premium Earnings | 25
December Thirty One Two Thousand Thirty Nine [Member] | Upfront [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2034, Total Expected Future Premium Earnings | 9
December Thirty One Two Thousand Thirty Nine [Member] | Installments [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2034, Total Expected Future Premium Earnings | 20
December Thirty One Two Thousand Thirty Nine [Member] | Accretion [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2034, Total Expected Future Premium Earnings | 6
December Thirty One Two Thousand Forty Four and Thereafter [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2044 and thereafter, Total Expected Future Premium Earnings | 28
December Thirty One Two Thousand Forty Four and Thereafter [Member] | Unearned Premium Revenue [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2044 and thereafter, Total Expected Future Premium Earnings | 0
December Thirty One Two Thousand Forty Four and Thereafter [Member] | Upfront [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2044 and thereafter, Total Expected Future Premium Earnings | 7
December Thirty One Two Thousand Forty Four and Thereafter [Member] | Installments [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2044 and thereafter, Total Expected Future Premium Earnings | 18
December Thirty One Two Thousand Forty Four and Thereafter [Member] | Accretion [Member] |
Insurance Premiums [Line Items] |
Five years ending, December 31, 2044 and thereafter, Total Expected Future Premium Earnings | $ 3

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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 -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-4 + 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 -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-4 + 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 -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-4 + 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 -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-4 + 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 -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-4 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in second 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 -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-4 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in fourth 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 -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-4 + Details
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