Condensed Consolidated Income Statements (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Net sales	$ 893,357	$ 895,637	$ 2,912,278	$ 2,852,408
Cost of goods sold	783,342	791,749	2,569,570	2,529,632
Gross profit	110,015	103,888	342,708	322,776
Selling, general and administrative expenses	77,688	72,691	236,569	220,642
Depreciation expense	3,417	3,352	9,954	10,059
Intangible amortization expense	5,005	5,103	14,708	15,600
Change in fair value of contingent consideration	5,101	4,801	11,535	28,595
Operating income	18,804	17,941	69,942	47,880
Interest expense	3,670	2,784	9,415	6,655
Interest income	(682)	(887)	(1,397)	(2,349)
Other expense, net	21	252	254	691
Income before income taxes	15,795	15,792	61,670	42,883
Provision for income taxes	4,080	5,143	15,651	20,118
Net income	$ 11,715	$ 10,649	$ 46,019	$ 22,765
Per share data:
Net income per common share, basic (in dollars per share)	$ 0.46	$ 0.42	$ 1.79	$ 0.89
Weighted-average shares outstanding, basic (in shares)	25,704	25,572	25,647	25,503
Net income per common share, diluted (in dollars per share)	$ 0.45	$ 0.42	$ 1.79	$ 0.89
Weighted-average shares outstanding, diluted (in shares)	25,762	25,606	25,755	25,607