Business Combination (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Business Combinations [Abstract]
Business Acquisition, Name of Acquired Entity	BCD Semiconductor Manufacturing Limited (“BCD”)
Business Acquisition, Effective Date of Acquisition	Mar. 05, 2013
Business Acquisition, Cost of Acquired Entity, Description of Purchase Price Components	the Company completed the acquisition of all the outstanding ordinary shares, par value $0.001 per share, of BCD (the “Shares”), including Shares represented by American Depository Shares (“ADSs”), which were cancelled in exchange for the right to receive $1.33-1/3 in cash per Share, without interest. Each ADS represented six Shares and was converted into the right to receive $8.00 in cash, without interest. The aggregate consideration was approximately $155 million, excluding acquisition costs, fees and expenses. In addition, a $5 million retention plan for employees of BCD, payable at the 12, 18 and 24 month anniversaries of the acquisition has been established.
Employee Retention Payable	$ 5,000,000
Business Acquisition, Period Results Included in Combined Entity	31 days
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual	15,000,000
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual	(1,000,000)
Business Combination, Reason for Business Combination	The Company’s purpose in making this acquisition is to further its strategy of expanding its market and growth opportunities through select strategic acquisitions. This acquisition is expected to enhance the Company’s analog product portfolio by expanding its standard linear and power management offerings, including AC/DC and DC/DC solutions for power adapters and chargers, as well as other electronic products. BCD’s established presence in Asia, with a particularly strong local market position in China, offers the Company even greater penetration of the consumer, computing and communications markets. Likewise, the Company believes it can achieve increased market penetration for BCD’s products by leveraging the Company’s own global customer base and sales channels. In addition, BCD has in-house manufacturing capabilities in China, as well as a cost-effective development team that can be deployed across multiple product families. The Company also believes it will be able to apply its packaging capabilities and expertise to BCD’s products in order to improve cost efficiencies, utilization and product mix.
Business Acquisition, Purchase Price Allocation, Status	A final determination of the allocation of the purchase price to the assets acquired and liabilities assumed has not been completed and the following table is considered preliminary. The final determination is subject to the completion of the valuation of the assets acquired and liabilities assumed, which is expected between the second and third quarter of 2013.
Business Acquisition, Purchase Price Allocation, Methodology	The fair value of the significant identified intangible assets was estimated by using the market approach, income approach and cost approach valuation methodologies. Inputs used in the methodologies primarily included projected future cash flows, discounted at a rate commensurate with the risk involved.
Acquired Finite-lived Intangible Asset, Amount	17,000,000
Acquired Finite-lived Intangible Asset, Residual Value	0
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	6 years
Business Acquisition, Purchase Price Allocation, Goodwill, Expected Tax Deductible Amount, Description	In addition, it is not anticipated that goodwill will be deductible for income tax purposes.
Acquired Inventory Reasonable Profit Allowance	The Company evaluated and adjusted its inventory for a reasonable profit allowance, which is intended to permit the Company to report only the profits normally associated with its activities following the acquisition as it relates to the work-in-progress and finished goods inventory. As such, the Company increased its inventory acquired from BCD by approximately $5 million, and will record that increase into cost of goods sold, of which approximately $2 million was recorded in the first quarter of 2013 and the remaining will be recorded in the second quarter of 2013 as all the acquired work-in-process and finished goods inventory will have been sold.
Acquired Inventory Adjustments	5,000,000
Acquired Inventory Expenses To Cost Of Goods Sold	2,000,000
BusinessAcquisitionCostOfAcquiredEntityPurchasePriceAbstract
Purchase price (cost of shares)	154,735,000
Acquisition related costs (included in selling, general and administrative expenses)	2,075,000
Total purchase price	156,810,000
BusinessAcquisitionProFormaInformationAbstract
Net revenues	198,065,000	175,691,000
Net income	(5,753,000)	2,194,000
Net income per common share-Basic	$ (0.13)	$ 0.05
Net income per common share-Diluted	$ (0.13)	$ 0.05
Business Acquisition, Pro Forma Information, Description	The following unaudited pro forma consolidated results of operations for the three months ended March 31, 2013 and 2012 have been prepared as if the acquisition of BCD had occurred at January 1, 2013 and January 1, 2012, respectively, for each year The unaudited pro forma consolidated results of operations do not purport to be indicative of the results that would have been obtained if the above acquisition had actually occurred as of the dates indicated or of those results that may be obtained in the future. The unaudited pro forma consolidated results of operations do not include the final adjustments to net income to give the final effects to depreciation of property, plant and equipment acquired and amortization of intangible assets acquired as the Company currently is working to complete its valuation of the assets and liabilities acquired and is unable to determine those final effects. Upon completion of the valuation, the Company intends to make adjustments for these items in future pro forma disclosures for BCD. These unaudited pro forma consolidated results of operations were derived, in part, from the historical consolidated financial statements of BCD and other available information and assumptions believed to be reasonable under the circumstances.
BusinessAcquisitionPurchasePriceAllocationAbstract
Cash and cash equivalents	29,819,000
Accounts receivable, net	20,862,000
Inventory	42,909,000
Prepaid expenses and other current assets	27,205,000
Property, plant and equipment, net	99,716,000
Deferred tax assets	1,612,000
Other long-term assets	5,497,000
Other intangible assets	17,200,000
Goodwill	2,192,000
Total assets acquired	247,012,000
Lines of credit	17,336,000
Accounts payable	34,758,000
Accrued liabilites and other	16,703,000
Deferred tax liability	5,055,000
Other liabilities	18,425,000
Total liabilities assumed	92,277,000
Total net assets acquired, net of cash acquired	$ 154,735,000