Income Taxes, Continued (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income tax reconciliation [Abstract]
Income (loss) before taxes, domestic	$ 84,760,000	$ (8,914,000)	$ 24,178,000
Income (loss) before taxes, foreign	43,196,000	37,285,000	(23,761,000)
Income before taxes, total	127,956,000	28,371,000	417,000
Provision for income taxes at federal statutory rate (35%)	44,785,000	9,930,000	146,000
State income taxes, net of federal benefit	3,302,000	(8,148,000)	(3,572,000)
Non deductible items	752,000	146,000	242,000
Worthless stock deduction	0	0	(410,000)
Foreign tax provision (credits)	1,517,000	2,385,000	(1,059,000)
Manufacturing deduction	(2,022,000)	0	0
State apportionment refund claim	(37,000)	2,900,000	0
Foreign earnings not taxed at federal rate	(4,549,000)	(6,872,000)	(2,031,000)
Contingency reserve	816,000	(484,000)	(3,697,000)
SemEquip NOL adjustment	0	0	(392,000)
Valuation allowance	(205,000)	(346,000)	2,675,000
Other	(291,000)	(416,000)	0
Provision (benefit) for income taxes	44,068,000	(905,000)	(8,098,000)
Tax settlement - California		5,400,000
Tax benefit due to exercise of stock options	740,000	(472,000)	149,000
Undistributed earnings of foreign subsidiaries	51,300,000
Income tax holiday [Abstract]
Income Tax Holiday, Description	The Company was granted an income tax holiday for a manufacturing facility in China. The tax holiday allows for tax-free operations through December 31, 2009, followed by operations at a reduced income tax rate of 12.5% on the profits generated in 2010 through 2012, with a return to the full statutory rate of 25% for periods thereafter
Income Tax Holiday, Aggregate Dollar Amount	1,700,000	2,700,000	2,300,000
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1,	806,000	1,817,000	7,227,000
Additions based on tax positions related to the current year	793,000	603,000	777,000
Additions for tax positions of prior years	129,000	0	0
Reclassification of deferred tax assets	132,000	0	0
Reductions for settlements with taxing authorities	0	(416,000)	(1,675,000)
Reductions of tax positions of prior years	(69,000)	(1,198,000)	(4,512,000)
Balance at December 31,	1,791,000	806,000	1,817,000
Income Tax Penalties and Interest [Abstract]
Income tax examination, interest expense	10,000	(75,000)
Income tax examination, interest accrued	80,000	144,000
Unrecognized tax benefits expected to be released within next twelve months	0
Federal [Member]
Income tax reconciliation [Abstract]
Tax settlement - California		(2,900,000)
Federal [Member] | Research and Development Tax Credit Carryforward [Member]
Tax credit carryforwards [Abstract]
Tax credit carryforward	1,200,000
State and Local [Member]
Tax credit carryforwards [Abstract]
NOL and tax credit valuation allowance	4,800,000
Decrease in valuation allowance	200,000
Income tax reconciliation [Abstract]
Tax settlement - California		8,300,000
State and Local [Member] | Research and Development Tax Credit Carryforward [Member]
Tax credit carryforwards [Abstract]
Tax credit carryforward	$ 1,900,000