Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Segment reporting information [Line Items]
Net Sales	$ 834,366	$ 540,344	$ 2,505,141	$ 1,615,687
Gross Profit	465,259	292,718	1,224,370	902,685
Semiconductor products
Segment reporting information [Line Items]
Net Sales	810,532	517,628	2,437,049	1,546,533
Gross Profit	441,425	270,002	1,156,278	833,531
Technology licensing
Segment reporting information [Line Items]
Net Sales	23,834	22,716	68,092	69,154
Gross Profit	$ 23,834	$ 22,716	$ 68,092	$ 69,154