Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Statement of Cash Flows [Abstract]
Net income (loss)	$ 45,202	$ 27,073
Bad debt expense	37	1,668
Deferred financing cost amortization	145	314
Depreciation and amortization	15,910	8,797
Loss (gain) on sale of assets	(24)	(40)
Non-cash compensation expense	2,745	2,843
Deferred income taxes	6,841	5,031
Accounts receivable	(10,686)	(2,007)
Inventories	(33,761)	(3,275)
Costs and estimated earnings in excess of billings	(2,025)	4,551
Prepaid expenses and other current assets	(6,062)	(8,783)
Other non-current assets	(275)	520
Accounts payable and accrued expenses	3,964	156
Billings in excess of costs and estimated earnings	11,496	14,402
Other non-current liabilities	1,642	4,345
Net cash provided by operating activities	35,149	55,595
Purchases of property and equipment	(5,391)	(3,700)
Proceeds from sale of assets	166	60
Cash paid in conjunction with business combinations	(92,694)	(28,952)
Net cash used in investing activities	(97,919)	(32,592)
Borrowings of debt	947,057	592,648
Repayments of debt	(915,928)	(592,643)
Cash paid for finance leases	(423)	(132)
Payments for Repurchase of Redeemable Noncontrolling Interest	(1,188)
Distribution to noncontrolling interest	(311)	(577)
Purchase of treasury stock	(1,490)	(5,437)
Net cash used in financing activities	27,717	(6,107)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(35,053)	16,896
CASH, CASH EQUIVALENTS, beginning of period		18,934
CASH, CASH EQUIVALENTS, end of period	18,524	35,830
Cash paid for interest	460	668
Cash paid for income taxes (net)	3,473	718
Options exercised	$ 0	$ 34