CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Revenues	$ 323,285	$ 334,813
Cost of revenues	268,863	246,386
Research and development expenses	6,865	32,133
Selling, general and administrative expenses	24,574	25,187
Income from operations	22,983	31,107
Interest income and other, net	(120)	566
Interest expense	(1,101)	(1,110)
Income before income taxes	21,762	30,563
Income tax provision	(7,950)	(10,961)
Net income	13,812	19,602
Basic income per share	$ 0.23	$ 0.33
Diluted income per share	$ 0.23	$ 0.33
Net income	13,812	19,602
Other comprehensive income (loss):
Defined benefit plans, net of tax of $(52) and $164, respectively	(83)	262
Unrealized gain (loss) on investments	0	300
Net gain (loss) on foreign exchange derivative instruments, net of tax of $206 and $474, respectively	326	756
Total other comprehensive income (loss)	243	1,318
Comprehensive Income	$ 14,055	$ 20,920