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Parent Company Financial Statements - Condensed Statement of Cash Flows (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Cash flows from operating activities |  |  |
Net income | $ 2,588 | $ 2,741 | $ 1,992
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Provision for deferred income taxes | (27) | (97) | (30)
Net change in other accrued income and expense | 282 | 561 | (70)
Net cash provided by operating activities | 3,610 | 3,905 | 4,574
Cash flows from investing activities |  |  |
Acquisition, net of cash consideration | 0 | 0 | 394
Other, net | (538) | (440) | (620)
Cash flows from financing activities |  |  |
Proceeds from long-term borrowings | 5,497 | 5,035 | 999
Payments on long-term borrowings | (1,009) | (824) | (907)
Proceeds from issuance of Series J preferred stock | 733 | 0 | 0
Redemption of Series E preferred stock | (350) | 0 | 0
Purchases of treasury stock | (396) | (594) | (1,800)
Dividends paid — common | (895) | (868) | (784)
Dividends paid — preferred | (138) | (100) | (97)
Other, net | 114 | 18 | (14)
Net increase in cash and cash equivalents | 178 | 211 | 182
Supplemental disclosure of cash flow information |  |  |
Interest received during the year | 11,077 | 10,092 | 6,135
Income taxes received during the year | 236 | 452 | 488
Parent Company |  |  |
Cash flows from operating activities |  |  |
Net income | 2,588 | 2,741 | 1,992
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Equity in undistributed income of subsidiaries | (1,438) | (847) | 448
Provision for deferred income taxes | (8) | (5) | 7
Net change in other accrued income and expense | (5) | 32 | 8
Net cash provided by operating activities | 1,137 | 1,921 | 2,455
Cash flows from investing activities |  |  |
Net investment in consolidated subsidiaries | (30) | (1) | 54
Advances to consolidated subsidiaries | (2,000) | 0 | 0
Acquisition, net of cash consideration | 0 | 0 | 538
Other, net | (64) | (41) | 24
Net cash provided (used) by investing activities | (2,094) | (42) | 616
Cash flows from financing activities |  |  |
Repayment of short-term borrowings assumed in acquisition | 0 | 0 | (500)
Proceeds from long-term borrowings | 2,341 | 1,998 | 499
Payments on long-term borrowings | (205) | (750) | 0
Purchases of treasury stock | (396) | (594) | (1,800)
Dividends paid — common | (895) | (868) | (784)
Dividends paid — preferred | (138) | (100) | (97)
Other, net | 111 | 14 | 2
Net cash provided (used) by financing activities | 1,201 | (300) | (2,680)
Net increase in cash and cash equivalents | 244 | 1,579 | 391
Cash and cash equivalents at beginning of year | 3,399 | 1,820 | 1,429
Cash and cash equivalents at end of year | 3,643 | 3,399 | 1,820
Supplemental disclosure of cash flow information |  |  |
Interest received during the year | 76 | 6 | 1
Interest paid during the year | 257 | 135 | 49
Income taxes received during the year | 51 | 43 | 28
Parent Company | Series J Preferred Stock |  |  |
Cash flows from financing activities |  |  |
Proceeds from issuance of Series J preferred stock | 733 | 0 | 0
Parent Company | Series E Preferred Stock |  |  |
Cash flows from financing activities |  |  |
Redemption of Series E preferred stock | $ (350) | $ 0 | $ 0

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- Definition The cash outflow for reacquisition of callable preferred stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 15 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-15 + Details
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- Definition Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 15 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-15 + Details
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- Definition Amount of cash outflow in the form of ordinary dividends to preferred shareholders of the parent entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 15 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-15 + Details
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- Definition The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-13 + Details
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- Definition The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-13 + Details
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- Definition Interest received on loans and other debt instruments during the current period. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 16 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-16 + Details
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