Shareholders' Equity - Summary of Preferred Dividends Declared on Preferred Stock Issued (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Class of Stock [Line Items]
Total preferred stock dividends declared	$ 876	$ 717	$ 599
Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 1,347.66	$ 1,606.63	$ 1,484.27
Total preferred stock dividends declared	$ 40	$ 48	$ 44
Series C Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 1,347.66	$ 1,606.63	$ 1,484.27
Total preferred stock dividends declared	$ 11	$ 13	$ 12
Series D Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 1,327.49	$ 1,586.18	$ 1,463.99
Total preferred stock dividends declared	$ 72	$ 86	$ 79
Series E Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 5,418.79	$ 6,423.37	$ 6,074.57
Total preferred stock dividends declared	$ 41	$ 50	$ 46
Series F Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 5,421.32	$ 6,425.91	$ 6,077.09
Total preferred stock dividends declared	$ 9	$ 10	$ 10
Series J Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 0	$ 0	$ 1,261.02
Total preferred stock dividends declared	$ 0	$ 0	$ 51
Series K Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 0	$ 796.88	$ 1,593.76
Total preferred stock dividends declared	$ 0	$ 20	$ 44
Series O Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 1,325	$ 1,325	$ 1,325
Total preferred stock dividends declared	$ 34	$ 34	$ 34
Series P Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 0	$ 1,623.09	$ 2,022.64
Total preferred stock dividends declared	$ 0	$ 97	$ 121
Series Q Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 1,844.75	$ 1,375	$ 1,375
Total preferred stock dividends declared	$ 37	$ 28	$ 28
Series R Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 1,563.75	$ 1,237.5	$ 1,237.5
Total preferred stock dividends declared	$ 38	$ 30	$ 30
Series S Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 1,448.25	$ 1,100	$ 1,100
Total preferred stock dividends declared	$ 20	$ 15	$ 16
Series T Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 950.00	$ 950.00	$ 950.00
Total preferred stock dividends declared	$ 26	$ 26	$ 26
Series U Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 912.50	$ 912.50	$ 912.50
Total preferred stock dividends declared	$ 27	$ 27	$ 27
Series V Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 1,031.25	$ 1,031.25	$ 1,031.25
Total preferred stock dividends declared	$ 31	$ 31	$ 31
Series W Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 1,875	$ 1,833.33	$ 0
Total preferred stock dividends declared	$ 113	$ 110	$ 0
Series X Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 1,875	$ 1,026.04	$ 0
Total preferred stock dividends declared	$ 169	$ 92	$ 0
Series Y Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 1,718.4	$ 0	$ 0
Total preferred stock dividends declared	$ 137	$ 0	$ 0
Series Z Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends declared (in dollars per share)	$ 932.36	$ 0	$ 0
Total preferred stock dividends declared	$ 71	$ 0	$ 0