CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net income (loss)	$ 122,021,000	$ 52,226,000	$ (79,520,000)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	13,976,000	15,640,000	14,759,000
Stock-based compensation expense	12,167,000	10,036,000	10,526,000
Inventory impairments and abandonments	853,000	2,903,000	148,618,000
Deferred and other income tax expense (benefit)	21,501,000	17,664,000	(37,245,000)
Gain on sale of fixed assets	(392,000)	(335,000)	(232,000)
Change in allowance for doubtful accounts	(68,000)	54,000	(74,000)
Equity in income of unconsolidated entities	(594,000)	(347,000)	(403,000)
Cash distributions of income from unconsolidated entities	132,000	306,000	408,000
Loss on extinguishment of debt, net	2,025,000	0	24,920,000
Changes in operating assets and liabilities:
(Increase) decrease in accounts receivable	(5,800,000)	6,524,000	(1,674,000)
Decrease in income tax receivable	460,000	315,000	0
(Increase) decrease in inventory	(147,511,000)	154,865,000	42,927,000
(Increase) decrease in other assets	(1,922,000)	3,000	323,000
Increase in trade accounts payable	1,199,000	1,040,000	4,720,000
Increase (decrease) in other liabilities	13,609,000	28,201,000	(14,418,000)
Net cash provided by operating activities	31,656,000	289,095,000	113,635,000
Cash flows from investing activities:
Capital expenditures	(14,645,000)	(10,642,000)	(21,356,000)
Proceeds from sale of fixed assets	456,000	478,000	251,000
Acquisition, net of cash acquired	0	0	(4,088,000)
Return of capital from unconsolidated entities	0	0	68,000
Net cash used in investing activities	(14,189,000)	(10,164,000)	(25,125,000)
Cash flows from financing activities:
Repayment of debt	(82,476,000)	(51,150,000)	(576,548,000)
Proceeds from issuance of new debt	0	0	500,000,000
Repayment of borrowings from credit facility	0	(390,000,000)	(425,000,000)
Borrowings from credit facility	0	390,000,000	425,000,000
Debt issuance costs	(901,000)	(202,000)	(6,137,000)
Repurchase of common stock	0	(3,327,000)	(34,624,000)
Tax payments for stock-based compensation awards	(3,044,000)	(2,686,000)	(1,969,000)
Stock option exercises and other financing activities	569,000	(1,832,000)	314,000
Net cash used in financing activities	(85,852,000)	(59,197,000)	(118,964,000)
(Decrease) increase in cash, cash equivalents, and restricted cash	(68,385,000)	219,734,000	(30,454,000)
Cash, cash equivalents, and restricted cash at beginning of period	342,528,000	122,794,000	153,248,000
Cash, cash equivalents, and restricted cash at end of period	$ 274,143,000	$ 342,528,000	$ 122,794,000