Loans and leases and allowance for credit losses - Leases Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Guaranteed amount included in the estimated residual value of leased assets associated with financing leases	$ 89	$ 96
Lessor, asset under operating lease	204	200
Lease income	$ 44	$ 56	$ 43
Operating Lease, Lease Income, Statement of Income or Comprehensive Income [Extensible Enumeration]	Other revenues from operations	Other revenues from operations	Other revenues from operations
Direct financing lease, interest income	$ 158	$ 136	$ 94