CONSOLIDATED CONDENSED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Statement Of Operations [Abstract]
NET SALES	$ 166,617	$ 160,577	$ 470,519	$ 491,938
COST OF GOODS SOLD	123,012	115,383	352,180	333,736
Gross profit	43,605	45,194	118,339	158,202
OPERATING EXPENSES
Selling, general and administrative	25,796	23,404	72,702	67,389
Research and development	9,084	7,304	24,466	20,355
Other operating (income) expenses	1,203	1,120	(155)	3,408
Total operating expenses	36,083	31,828	97,013	91,152
Income from operations	7,522	13,366	21,326	67,050
OTHER INCOME (EXPENSES)	1,923	(2,300)	2,861	(7,444)
Income before income taxes and noncontrolling interest	9,445	11,066	24,187	59,606
INCOME TAX PROVISION	509	359	1,983	9,912
NET INCOME	8,936	10,707	22,204	49,694
Less: NET INCOME attributable to noncontrolling interest	(383)	(750)	(2,127)	(2,072)
NET INCOME attributable to common stockholders	$ 8,553	$ 9,957	$ 20,077	$ 47,622
EARNINGS PER SHARE attributable to common stockholders
Basic	$ 0.19	$ 0.22	$ 0.44	$ 1.05
Diluted	$ 0.18	$ 0.21	$ 0.43	$ 1.02
Number of shares used in computation
Basic	45,997	45,603	45,702	45,252
Diluted	46,995	47,093	46,901	46,875