Borrowings - Expected Maturities of Long-term Borrowings (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
2024	$ 4,500
2025	6,000
2026	4,700
2027	4,700
2028	4,400
2029-2048	29,800
Total	53,402	$ 61,026
Long-Term Borrowings [Member]
Debt Instrument [Line Items]
2024	4,528
2025	5,920
2026	4,638
2027	4,668
2028	4,380
2029-2048	29,546
Total before hedge accounting adjustments	53,680
Hedge accounting adjustments	(278)
Total	53,402
Long-Term Borrowings [Member] \| Senior Unsecured Debt [Member]
Debt Instrument [Line Items]
2024	0
2025	552
2026	523
2027	694
2028	513
2029-2048	3,069
Total before hedge accounting adjustments	5,351
Hedge accounting adjustments	(157)
Total	5,194
Long-Term Borrowings [Member] \| Secured Borrowings [Member]
Debt Instrument [Line Items]
2024	4,528
2025	5,368
2026	4,115
2027	3,974
2028	3,867
2029-2048	26,477
Total before hedge accounting adjustments	48,329
Hedge accounting adjustments	(121)
Total	$ 48,208

ASC 815 - Derivatives and Hedging fair value adjustments.

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