Quarterly Financial Information (Unaudited) - Summary of Quarterly Financial Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Selected Quarterly Financial Information [Abstract]
Net sales	$ 304,632	$ 394,991	$ 396,255	$ 259,708	$ 346,121	$ 327,454	$ 293,121	$ 212,278	$ 1,355,586	$ 1,178,974	$ 899,259
Gross profit	71,864	126,387	122,460	88,609	112,287	106,837	97,849	72,978	409,320	389,951	296,050
Net income (loss)	$ (4,776)	$ 27,476	$ 35,818	$ 16,707	$ 38,593	$ 21,769	$ 22,640	$ 10,148	$ 75,225	$ 93,150	$ (122,233)
Net income (loss) per common share:
Basic	$ (0.03)	$ 0.18	$ 0.23	$ 0.11	$ 0.25	$ 0.14	$ 0.15	$ 0.07	$ 0.49	$ 0.61	$ (1.01)
Diluted	$ (0.03)	$ 0.18	$ 0.23	$ 0.11	$ 0.25	$ 0.14	$ 0.14	$ 0.07	$ 0.49	$ 0.59	$ (1.01)