Employee Pension and Other Postretirement Benefits (Tables)

9 Months Ended

Sep. 30, 2020

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

The costs of the Company's defined benefit pension plans and other postretirement benefit plans for the three and nine months ended September 30, 2020 and 2019, were as follows:

	Three Months Ended September 30								Nine Months Ended September 30
	Pension Benefits				Other Benefits				Pension Benefits				Other Benefits
($ in millions)	2020		2019		2020		2019		2020		2019		2020		2019
Components of Net Periodic Benefit Cost
Service cost	$	45	$	36	$	2	$	2	$	135	$	108	$	7	$	5
Interest cost	64		69		4		5		193		208		12		15
Expected return on plan assets	(122)		(102)		—		—		(365)		(305)		—		—
Amortization of prior service cost (credit)	3		4		(5)		(5)		9		13		(16)		(16)
Amortization of net actuarial loss (gain)	28		29		(2)		(3)		82		85		(5)		(8)
Net periodic benefit cost	$	18	$	36	$	(1)	$	(1)	$	54	$	109	$	(2)	$	(4)

Schedule of Defined Benefit Plans Disclosures, Cash Contributions

The Company made the following contributions to its defined benefit pension plans and other postretirement benefit plans for the nine months ended September 30, 2020 and 2019:

	Nine Months Ended September 30
($ in millions)	2020		2019
Pension plans
Discretionary
Qualified	$	205	$	21
Non-qualified	6		5
Other benefit plans	25		23
Total contributions	$	236	$	49