Short-term borrowings (Tables)

12 Months Ended

Dec. 31, 2020

Debt Disclosure [Abstract]

Schedule of Short-term Debt

A summary of short-term borrowings for the years 2020, 2019 and 2018 is presented in the following table:

(Dollars in millions)	Trading Liabilities			Federal Funds Purchased			Securities Sold Under Agreements to Repurchase			Other Short-term Borrowings
2020
Average balance	$	457		$	862		$	1,109		$	626
Year-end balance	353			845			1,187			166
Maximum month-end outstanding	983			1,487			1,661			4,061
Average rate for the year	1.24		%	0.34		%	0.46		%	0.92		%
Average rate at year-end	0.77			0.10			0.26			0.09
2019
Average balance	$	503		$	738		$	701		$	538
Year-end balance	506			548			717			2,253
Maximum month-end outstanding	754			1,282			772			2,276
Average rate for the year	2.48		%	2.08		%	1.89		%	2.34		%
Average rate at year-end	2.07			1.55			1.72			2.14
2018
Average balance	$	683		$	405		$	714		$	1,047
Year-end balance	335			257			763			115
Maximum month-end outstanding	891			503			891			2,229
Average rate for the year	2.83		%	1.89		%	1.40		%	1.82		%
Average rate at year-end	3.21			2.50			1.66			2.48