Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Difference between income tax provision computed at the statutory Federal income tax rate and financial statement income tax related to continuing operations
Provision at Federal rate of 35%									$ 21,532	$ 27,028	$ 26,590
State income taxes, net of Federal impact									1,808	101	322
Research and experimentation credits									(16,683)	(3,651)	(3,036)
Tax uncertainties									4,878	1,333
Section 199 manufacturing deduction									(2,263)	(4,246)	(972)
Foreign rate differential									1,133	3,108	3,564
Valuation allowance for deferred tax assets									(3,312)	3,550	3,395
Other impact of foreign operations									2,088	672	3,470
Other									987	450	357
Total income tax provision	$ 3,401	$ 1,331	$ 6,790	$ (1,354)	$ 1,866	$ 7,701	$ 6,972	$ 11,806	$ 10,168	$ 28,345	$ 33,690