Fair Value Disclosures - Financial Assets and Liabilities Not Recorded at Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Financial assets:
HTM securities	$ 53,905	$ 1,495
Loans and leases HFI, net of ALLL	299,475	285,078
Financial liabilities:
Long-term debt	30,319	35,913
Carrying Amount
Financial assets:
HTM securities	60,081	1,494
Loans and leases HFI, net of ALLL	299,455	285,055
Financial liabilities:
Time deposits	13,562	15,886
Long-term debt	30,319	35,913
Fair Value | Level 2
Financial assets:
HTM securities	53,905	1,495
Financial liabilities:
Time deposits	13,660	16,017
Long-term debt	29,020	36,251
Fair Value | Level 3
Financial assets:
Loans and leases HFI, net of ALLL	$ 292,846	$ 284,914