Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
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%																	$ 21,533	$ 21,532	$ 27,028
State income taxes, net of Federal impact																	2,070	1,808	101
Research and experimentation credits																	(2,045)	(16,683)	(3,651)
Tax uncertainties																	596	4,878	1,333
Section 199 manufacturing deduction																	(1,936)	(2,263)	(4,246)
Foreign rate differential																	2,847	1,133	3,108
Valuation allowance for deferred tax assets																	3,602	(3,312)	3,550
Other impact of foreign operations																	(3,555)	2,088	672
Other																	1,451	987	450
Total income tax provision	$ 4,083	[1]	$ 4,831	[1]	$ 8,338	[1]	$ 7,311	[1]	$ 3,401	[1]	$ 1,331	[1]	$ 6,790	[1]	$ (1,354)	[1]	$ 24,563	$ 10,168	$ 28,345

[1] Fluctuations in our effective income tax rate between quarters generally relates to the accounting for discrete income tax items in any given quarter, and revisions of estimates for certain income tax components during the year. •For 2014: Our effective income tax rates for the first, second, third, and fourth quarters were 43%, 47%, 48%, and 24%, respectively. The low fourth quarter rate can be mainly attributed to full year impact of the 2014 R&D tax credits, as the legislation was not passed until December 2014.•For 2013: Our effective income tax rates for the first, second, third, and fourth quarters of 2013 were (10)%, 36%, 8%, and 27%, respectively. The negative rate in the first quarter of 2013 reflects the benefit of approximately $6 million of R&D tax credits that we generated in 2012, but were unable to include in the determination of our 2012 effective tax rate as the legislation was not signed into law until 2013. The lower income tax rates for the third and fourth quarter were mainly driven by incremental R&D income tax credits claimed for development activities from previous years and by the reduction of certain tax allowances related mainly to foreign operations, offset by increases in tax reserves for uncertainties, which provided a benefit of approximately $6 million and $2 million, respectively.