Quarterly Summary of Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 374,910	$ 938,735	$ 542,205	$ 276,839	$ 394,130	$ 873,800	$ 501,913	$ 250,594	$ 2,132,689	$ 2,020,437	$ 1,903,339
Gross profit	192,998	507,632	273,024	130,019	203,305	470,093	251,887	114,965	1,103,673	1,040,250	931,642
(Loss) income from operations	16,655	255,766	97,131	(31,417)	31,604	244,718	90,412	(39,414)	338,135	327,320	222,584
Net income	$ 16,090	$ 201,593	$ 77,810	$ (19,351)	$ 23,969	$ 196,374	$ 74,372	$ (30,407)	$ 276,142	$ 264,308	$ 114,394
Net (loss) income per share
Basic (in dollars per share)	$ 0.57	$ 7.21	$ 2.73	$ (0.67)	$ 0.82	$ 6.74	$ 2.49	$ (1.00)	$ 9.73	$ 8.92	$ 3.60
Diluted (in dollars per share)	$ 0.57	$ 7.14	$ 2.71	$ (0.67)	$ 0.82	$ 6.68	$ 2.48	$ (1.00)	$ 9.62	$ 8.84	$ 3.58