Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2020

Retirement Benefits [Abstract]

Components of Net Periodic Benefit Cost

The components of net periodic benefit cost for defined benefit pension plans are summarized in the following table:

Three Months Ended March 31, (Dollars in millions)	Location	2020		2019
Service cost	Personnel expense	$	118	$	54
Interest cost	Other expense	78		57
Estimated return on plan assets	Other expense	(216)		(113)
Amortization and other	Other expense	19		25
Net periodic benefit cost		$	(1)	$	23