Consolidated Statements of Cash Flows - USD ($) $ in Millions		6 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Operating Activities
Net income (loss)	[1]	$ (226.8)	$ (146.0)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	[1]	94.7	268.7
Stock-based compensation	[1]	12.2	9.8
Certain interest expense and other financing costs	[1]	5.6	5.7
Loss on debt extinguishment	[1]	9.5	14.7
Gain on sale of fixed assets and other	[1]	(1.4)	(0.9)
Deferred income taxes	[1]	(164.6)	(49.4)
Loss on sale of Interior Products	[1],[2]	357.8	0.0
338(h)(10) election refund	[1]	0.0	(5.3)
Changes in operating assets and liabilities:
Accounts receivable	[1]	137.7	199.1
Inventories	[1]	(227.0)	(21.8)
Prepaid expenses and other current assets	[1]	45.4	6.5
Accounts payable and accrued expenses	[1]	(167.6)	(434.9)
Other assets and liabilities	[1]	1.4	3.0
Net cash provided by (used in) operating activities	[1]	(123.1)	(150.8)
Investing Activities
Purchases of property and equipment	[1]	(32.1)	(25.0)
Proceeds from sale of Interior Products	[1],[2]	837.0	0.0
Proceeds from the sale of assets	[1]	1.5	1.1
Net cash provided by (used in) investing activities	[1]	806.4	(23.9)
Financing Activities
Borrowings under revolving lines of credit	[1]	2.3	2,029.3
Payments under revolving lines of credit	[1]	(259.3)	(1,109.9)
Payments under term loan	[1]	(428.8)	(4.9)
Borrowings under senior notes	[1]	0.0	300.0
Payment under senior notes	[1]	0.0	(309.6)
Payment of debt issuance costs	[1]	0.0	(3.7)
Payments under equipment financing facilities and finance leases	[1]	(3.4)	(4.4)
Payment of dividends on Preferred Stock	[1]	(12.0)	(12.0)
Proceeds from issuance of common stock related to equity awards	[1]	17.7	1.4
Payment of taxes related to net share settlement of equity awards	[1]	(4.3)	(2.8)
Net cash provided by (used in) financing activities	[1]	(687.8)	883.4
Effect of exchange rate changes on cash and cash equivalents	[1]	(0.8)	0.2
Net increase (decrease) in cash and cash equivalents	[1]	(5.3)	708.9
Cash and cash equivalents, beginning of period	[1]	624.6	72.3
Cash and cash equivalents, end of period	[1]	619.3	781.2
Supplemental Cash Flow Information
Operating cash flows provided by (used in) discontinued operations	[1]	(28.2)	19.2
Investing cash flows provided by (used in) discontinued operations	[1]	(2.5)	(6.7)
Cash paid during the period for:
Interest	[1]	56.5	63.7
Income taxes paid (received), net of refunds	[1]	17.9	(0.4)
Supplemental Disclosure of Non-Cash Investing and Financing Activities
Finance lease liabilities arising from obtaining right-of-use assets	[1]	$ 14.9	$ 0.0

[1] Unless otherwise noted, amounts include both continuing and discontinued operations.

[2] See Note 3 for additional information.