Segment Reporting - Net Sales by Product Type (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016
Segment Reporting Information [Line Items]
Net sales	$ 631,124	$ 532,721	$ 1,812,046	$ 1,691,303
Product concentration risk | Net sales
Segment Reporting Information [Line Items]
Percent of Net Sales	100.00%	100.00%	100.00%	100.00%
Server systems
Segment Reporting Information [Line Items]
Net sales	$ 441,822	$ 372,404	$ 1,243,313	$ 1,182,362
Server systems | Product concentration risk | Net sales
Segment Reporting Information [Line Items]
Percent of Net Sales	70.00%	69.90%	68.60%	69.90%
Subsystems and accessories
Segment Reporting Information [Line Items]
Net sales	$ 189,302	$ 160,317	$ 568,733	$ 508,941
Subsystems and accessories | Product concentration risk | Net sales
Segment Reporting Information [Line Items]
Percent of Net Sales	30.00%	30.10%	31.40%	30.10%