Securities - Pledged assets (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Pledged Assets [Line Items]
Assets	$ 452,621	$ 444,438
Securities	150,844	158,705
Loans	69,347	67,787
Trading assets	10,759	16,577
Interest-bearing deposits with banks	16,639	16,630
Pledged assets permitted to be sold or repledged	92,000	122,000
Market value of securities received as collateral that have been sold or repledged	57,000	78,000
Cash segregated under federal or other regulations	4,441	3,822
Securities segregated under federal or other regulations	5,000	4,000
Asset Pledged as Collateral
Pledged Assets [Line Items]
Assets	140,000	144,000
Securities	123,000	126,000
Loans	13,000	12,000
Trading assets	3,000	5,000
Interest-bearing deposits with banks	1,000	1,000
Financial instruments, owned, at fair value	21,000	24,000
Asset Pledged as Collateral | Federal Home Loan Bank Advances
Pledged Assets [Line Items]
Assets	8,000	7,000
Asset Pledged as Collateral | Federal Reserve Discount Window Borrowings
Pledged Assets [Line Items]
Assets	$ 111,000	$ 112,000