Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Adjustments to reconcile loss from continuing operations to net cash provided by operating activities:
Depreciation and amortization	$ 212	$ 225
Share-based compensation	14	11
Amortization of Debt Issuance Costs and Discounts	14	11
Deferred income taxes, net	(17)	3
Change in fair value of emergence date warrants	(3)	(21)
Unrealized loss on foreign currency transactions	8	12
Marketable Securities, Unrealized Gain (Loss)	(19)	0
Marketable Securities, Realized Gain (Loss)	(11)	0
Other non-cash credits, net	(6)	7
Increase (Decrease) in Receivables	41	74
Changes in operating assets and liabilities:
Inventory	6	(9)
Operating lease right-of-use assets	(12)	0
Contract assets	(53)	(68)
Contract costs	(13)	(30)
Accounts payable	(31)	5
Payroll and benefit obligations	(24)	(63)
Business restructuring reserve	(13)	(15)
Operating lease liabilities	(10)	0
Contract liabilities	(30)	50
Other assets and liabilities	47	(65)
NET CASH PROVIDED BY OPERATING ACTIVITIES	32	123
INVESTING ACTIVITIES:
Capital expenditures	(48)	(47)
Proceeds from Sale and Maturity of Marketable Securities	294	0
Other investing activities, net	0	(1)
NET CASH (USED FOR) PROVIDED BY INVESTING ACTIVITIES	246	(48)
Payments for Repurchase of Common Stock	(330)	0
Proceeds from Issuance of Preferred Stock and Preference Stock	121	0
FINANCING ACTIVITIES:
Repayment of long-term debt	(250)	(15)
Payment for Contingent Consideration Liability, Financing Activities	(5)	(9)
Payments related to sale-leaseback transactions	(5)	(8)
Other financing activities, net	(3)	(7)
NET CASH USED FOR FINANCING ACTIVITIES	(472)	(39)
Effect of exchange rate changes on cash and cash equivalents	(5)	(1)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(199)	35
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	557	739
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	10	0
Net income (loss)	$ (726)	$ (4)