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Comprehensive Income - Schedule of Changes in Balances of Each Component of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Changes In Accumulated Other Comprehensive Income [Roll Forward] |  |  |
Beginning Balance | $ (253) | $ 58 |
Other comprehensive income before reclassifications | (74) | 296 |
Amounts reclassified from accumulated other comprehensive income | 19 | (15) |
Income Tax Expense (Benefit) | (7) | (2) | $ (18)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent | 93 | (310) |
Ending Balance | (160) | (253) | 58
Unrealized Gains (Losses) on Available-for-Sale Securities [Member] |  |  |
Changes In Accumulated Other Comprehensive Income [Roll Forward] |  |  |
Beginning Balance | (71) | 154 |
Other comprehensive income before reclassifications | (31) | 211 |
Amounts reclassified from accumulated other comprehensive income | 21 | (14) |
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent | 51 | (225) |
Ending Balance | (20) | (71) | 154
Accumulated Translation Adjustment [Member] |  |  |
Changes In Accumulated Other Comprehensive Income [Roll Forward] |  |  |
Beginning Balance | (184) | (100) |
Other comprehensive income before reclassifications | (40) | 85 |
Amounts reclassified from accumulated other comprehensive income | 0 | 0 |
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent | 40 | (85) |
Ending Balance | (144) | (184) | (100)
Accumulated Gain (Loss), Financial Liability, Fair Value Option, Attributable to Parent [Member] |  |  |
Changes In Accumulated Other Comprehensive Income [Roll Forward] |  |  |
Beginning Balance | (1) | (1) |
Other comprehensive income before reclassifications | 0 | 0 |
Amounts reclassified from accumulated other comprehensive income | 0 | 0 |
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent | 0 | 0 |
Ending Balance | (1) | (1) | (1)
Other Postretirement Benefits Plan [Member] |  |  |
Changes In Accumulated Other Comprehensive Income [Roll Forward] |  |  |
Beginning Balance | 3 | 4 |
Other comprehensive income before reclassifications | (3) | 0 |
Amounts reclassified from accumulated other comprehensive income | (1) | (1) |
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent | 2 | (1) |
Ending Balance | $ 5 | $ 3 | $ 4

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- Definition Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-14A Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-11 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Subparagraph (g)(2)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480016/944-40-65-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Subparagraph (h)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480016/944-40-65-2 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(30)(a)(4)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(23)(a)(3)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-14 + Details
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