CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Revenue	$ 392,975	$ 369,380	$ 737,492	$ 720,923
Cost of goods sold	203,360	186,662	371,980	369,673
Gross profit	189,615	182,718	365,512	351,250
Operating expenses:
Research and development	35,154	36,307	69,848	72,633
Selling, general and administrative	83,476	83,500	158,611	165,442
Restructuring expenses	454	3,547	768	11,361
Total operating expenses	119,084	123,354	229,227	249,436
Earnings from operations	70,531	59,364	136,285	101,814
Interest expense	3,358	3,629	7,019	7,337
Interest income	(295)	(272)	(542)	(536)
Other expense (income), net	1,020	(1,070)	320	(1,269)
Earnings before income taxes	66,448	57,077	129,488	96,282
Income tax provision	15,948	12,319	31,078	21,630
Net earnings	$ 50,500	$ 44,758	$ 98,410	$ 74,652
Earnings per share:
Basic	$ 0.36	$ 0.32	$ 0.70	$ 0.53
Diluted	$ 0.36	$ 0.31	$ 0.70	$ 0.52
Weighted average shares outstanding:
Basic	140,063	141,574	139,916	141,255
Diluted	141,491	144,120	141,484	143,964