Retirement Benefit Liabilities (Tables)

6 Months Ended

Mar. 31, 2021

Retirement Benefits [Abstract]

Schedule of Retirement Benefit Liabilities

Retirement benefit liabilities consisted of the following (in millions):

	March 31, 2021		September 30, 2020
Retiree medical liability	$	51	$	52
Pension liability	120		139
Other	17		17
Subtotal	188		208
Less: current portion (included in compensation and benefits, Note 11)	(12)		(12)
Retirement benefits	$	176	$	196

Schedule of Components of Net Periodic Pension and Retiree Medical Income

The components of net periodic pension and retiree medical income included in continuing operations for the three months ended March 31 are as follows (in millions):

	2021				2020
	Pension		Retiree Medical		Pension		Retiree Medical
Interest cost	$	(8)	$	(1)	$	(10)	$	(1)
Assumed return on plan assets	24		—		24		—
Amortization of prior service benefit	—		9		—		9
Recognized actuarial loss	(8)		(3)		(8)		(3)
Total income	$	8	$	5	$	6	$	5

The components of net periodic pension and retiree medical income included in continuing operations for the six months ended March 31 are as follows (in millions):

	2021				2020
	Pension		Retiree Medical		Pension		Retiree Medical
Interest cost	$	(17)	$	(1)	$	(21)	$	(1)
Assumed return on plan assets	48		—		48		—
Amortization of prior service benefit	—		18		—		18
Recognized actuarial loss	(16)		(6)		(16)		(7)
Total income	$	15	$	11	$	11	$	10