Consolidated Statements of Operations - USD ($) $ in Thousands		12 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Net sales		$ 7,105,160	$ 6,418,311	$ 4,376,670
Cost of products sold		5,368,605	4,824,990	3,300,731
Gross profit		1,736,555	1,593,321	1,075,939
Operating expense:
Selling, general and administrative		1,311,043	1,187,192	743,376
Depreciation		70,695	60,318	34,002
Amortization		207,065	141,185	82,465
Total operating expense		1,588,803	1,388,695	859,843
Income (loss) from operations		147,752	204,626	216,096
Interest expense, financing costs, and other		158,534	136,544	52,751
Income (loss) before provision for income taxes		(10,782)	68,082	163,345
Provision for (benefit from) income taxes	[1]	(170)	(30,544)	62,481
Net income (loss)		(10,612)	98,626	100,864
Dividends on preferred shares	[2]	24,000	18,000	0
Net income (loss) attributable to common shareholders		$ (34,612)	$ 80,626	$ 100,864
Weighted-average common stock outstanding:
Basic		68,424,288	68,012,879	60,315,648
Diluted		68,424,288	69,191,039	61,344,263
Net income (loss) per share:
Basic	[3]	$ (0.51)	$ 1.07	$ 1.67
Diluted	[3]	$ (0.51)	$ 1.05	$ 1.64

[1] Year ended September 30, 2018 amounts include a net tax benefit $49.2 million resulting from recording the provisional impact of the enactment of the 2017 Tax Cuts and Jobs Act (“TCJA”).

[2] Year ended September 30, 2019 amount is composed of $5.0 million in undeclared cumulative Preferred Stock dividends, as well as an additional $19.0 million of Preferred Stock dividends that had been declared and paid as of period end. Year ended September 30, 2018 amount is composed of $5.0 million in undeclared cumulative Preferred Stock dividends, as well as an additional $13.0 million of Preferred Stock dividends that had been declared and paid as of period end. See Note 3 for further discussion.

[3] See Note 5 for detailed calculations and further discussion.