CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Net sales	$ 2,545,641	$ 2,132,689	$ 2,020,437
Cost of sales	1,171,551	1,029,016	980,187
Gross profit	1,374,090	1,103,673	1,040,250
Selling, general, and administrative expenses	869,885	765,538	712,930
Income from operations	504,205	338,135	327,320
Interest income	(2,637)	(7,261)	(6,028)
Interest expense	6,028	5,046	4,661
Other income, net	(700)	(516)	(247)
Total other expense (income), net	2,691	(2,731)	(1,614)
Income before income taxes	501,514	340,866	328,934
Income tax expense	118,939	64,724	64,626
Net income	382,575	276,142	264,308
Other comprehensive income (loss)
Unrealized loss on cash flow hedges, net of tax	0	0
Unrealized loss on cash flow hedges, net of tax			(243)
Foreign currency translation gain (loss)	8,816	(2,905)	(9,428)
Total other comprehensive income (loss)	8,816	(2,905)	(9,671)
Comprehensive income	$ 391,391	$ 273,237	$ 254,637
Net income per share
Basic (in dollars per share)	$ 13.64	$ 9.73	$ 8.92
Diluted (in dollars per share)	$ 13.47	$ 9.62	$ 8.84
Weighted-average common shares outstanding
Basic (in shares)	28,055	28,385	29,641
Diluted (in shares)	28,406	28,694	29,903