CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
NET SALES	$ 224,810	$ 186,549	$ 427,844	$ 357,618
COST OF SALES	124,801	102,408	239,779	197,535
GROSS PROFIT	100,009	84,141	188,065	160,083
OPERATING EXPENSES:
Selling, general and administrative	69,095	57,409	134,007	115,180
Research and development	15,316	13,313	29,638	25,838
Contingent consideration expense (benefit)	178	(18)	219	19
Acquired in-process research and development	306	75	306	75
Total operating expenses	84,895	70,779	164,170	141,112
INCOME FROM OPERATIONS	15,114	13,362	23,895	18,971
OTHER INCOME (EXPENSE):
Interest income	342	89	487	172
Interest expense	(3,338)	(1,639)	(5,736)	(4,345)
Gain on bargain purchase	0	(669)	0	11,574
Other income (expense) - net	(553)	170	(721)	434
Other income (expense) — net	(3,549)	(2,049)	(5,970)	7,835
INCOME BEFORE INCOME TAXES	11,565	11,313	17,925	26,806
INCOME TAX EXPENSE	624	1,830	1,715	2,520
NET INCOME	$ 10,941	$ 9,483	$ 16,210	$ 24,286
EARNINGS PER COMMON SHARE:
Basic (in dollars per share)	$ 0.22	$ 0.19	$ 0.32	$ 0.51
Diluted (in dollars per share)	$ 0.21	$ 0.19	$ 0.31	$ 0.50
AVERAGE COMMON SHARES:
Basic (in shares)	50,473	49,957	50,376	47,406
Diluted (in shares)	52,154	51,188	52,033	48,516