Power Integrations (POWI) 10-Q 5 May 14 2014 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information Document	3 Months Ended
	Mar. 31, 2014	Apr. 18, 2014
Entity Information [Line Items]	'	'
Entity Registrant Name	'POWER INTEGRATIONS INC	'
Entity Central Index Key	'0000833640	'
Trading Symbol	'POWI	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Large Accelerated Filer	'
Document Type	'10-Q	'
Document Period End Date	31-Mar-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q1	'
Amendment Flag	'false	'
Entity Common Stock, Shares Outstanding	'	30,419,313

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
CURRENT ASSETS:	'	'
Cash and cash equivalents	$83,967	$92,928
Short-term marketable securities	133,684	109,179
Accounts receivable, net of allowances of $105 and $120 in 2014 and 2013, respectively (Note 2)	16,421	12,389
Inventories	47,934	42,235
Deferred tax assets	2,059	2,059
Prepaid expenses and other current assets	17,027	18,632
Total current assets	301,092	277,422
PROPERTY AND EQUIPMENT, net	92,142	90,141
INTANGIBLE ASSETS, net	38,478	40,334
GOODWILL	80,599	80,599
DEFERRED TAX ASSETS	5,686	9,449
OTHER ASSETS	3,332	3,476
Total assets	521,329	501,421
CURRENT LIABILITIES:	'	'
Accounts payable	23,600	20,772
Accrued payroll and related expenses	8,046	8,900
Taxes payable	1,768	2,266
Deferred tax liabilities	1,325	943
Deferred income on sales to distributors	17,844	15,727
Other accrued liabilities	1,698	1,810
Total current liabilities	54,281	50,418
LONG-TERM INCOME TAXES PAYABLE	2,612	6,885
DEFERRED TAX LIABILITIES	4,991	5,273
OTHER LIABILITIES	2,267	2,159
Total liabilities	64,151	64,735
COMMITMENTS AND CONTINGENCIES (Notes 9, 11 and 12)	'	'
STOCKHOLDERS’ EQUITY:	'	'
Common stock	30	30
Additional paid-in capital	234,667	223,660
Accumulated other comprehensive loss	-315	-470
Retained earnings	222,796	213,466
Total stockholders’ equity	457,178	436,686
Total liabilities and stockholders’ equity	$521,329	$501,421

CONDENSED_CONSOLIDATED_BALANCE1

CONDENSED CONSOLIDATED BALANCE SHEETS (PARENTHETICAL) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Statement of Financial Position [Abstract]	'	'
Accounts receivable, allowance	($105)	($120)

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013
NET REVENUES	$83,073		$77,040
COST OF REVENUES	37,096		37,176
GROSS PROFIT	45,977		39,864
OPERATING EXPENSES:	'		'
Research and development	13,490		12,272
Sales and marketing	12,110		10,781
General and administrative	7,646		7,734
Total operating expenses	33,246		30,787
INCOME FROM OPERATIONS	12,731		9,077
OTHER INCOME	'		'
Other income, net	257		217
Total other income	257		217
INCOME BEFORE PROVISION FOR (BENEFIT FROM) INCOME TAXES	12,988		9,294
PROVISION FOR (BENEFIT FROM) INCOME TAXES	625		-1,609
NET INCOME	$12,363		$10,903
EARNINGS PER SHARE:	'		'
Basic	$0.41		$0.38
Diluted	$0.40	[1]	$0.37	[1]
SHARES USED IN PER SHARE CALCULATION:	'		'
Basic	30,239		28,754
Diluted	31,167	[1]	29,783	[1]
[1]	The Company includes the shares underlying performance-based awards in the calculation of diluted earnings per share if the performance conditions have been satisfied as of the end of the reporting period and excludes such shares when the necessary conditions have not been met. The Company has excluded the shares underlying the 2014 and 2013 awards in the 2014 and 2013 calculation, respectively, as those shares were not contingently issuable as of the end of the period.

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Net income	$12,363	$10,903
Other comprehensive income (loss), net of tax:	'	'
Foreign currency translation adjustments, net of $0 tax in the quarters ended March 31, 2014 and 2013 (Note 2)	-6	-151
Unrealized gain (loss) on marketable securities, net of $0 tax in the quarters ended March 31, 2014 and 2013 (Note 2)	147	-54
Amortization of defined benefit pension items, net of tax of $4 and $4 in the quarters ended March 31, 2014 and 2013, respectively (Note 2)	14	14
Total other comprehensive income (loss)	155	-191
Total comprehensive income	$12,518	$10,712

CONDENSED_CONSOLIDATED_STATEME2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (PARENTHETICAL) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Foreign currency translation adjustments, tax	$0	$0
Unrealized gain (loss) on marketable securities, tax	0	0
Amortization of defined benefit pension items, tax	$4	$4

CONDENSED_CONSOLIDATED_STATEME3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
CASH FLOWS FROM OPERATING ACTIVITIES:	'	'
Net income	$12,363	$10,903
Adjustments to reconcile net income to net cash provided by operating activities:	'	'
Depreciation	3,971	3,975
Amortization of intangibles	1,856	1,842
Loss on sale of property and equipment	159	0
Stock-based compensation expense	3,915	3,636
Amortization of premium on marketable securities	394	104
Deferred income taxes	3,864	-3,236
Reduction in accounts receivable allowances	-15	-20
Change in operating assets and liabilities:	'	'
Accounts receivable	-4,017	-7,393
Inventories	-5,652	893
Prepaid expenses and other assets	1,825	3,928
Accounts payable	1,088	2,832
Taxes payable and accrued liabilities	-5,624	1,172
Deferred income on sales to distributors	2,116	2,936
Net cash provided by operating activities	16,243	21,572
CASH FLOWS FROM INVESTING ACTIVITIES:	'	'
Purchases of property and equipment	-4,465	-3,950
Purchases of marketable securities	-24,751	-19,422
Proceeds from maturities of marketable securities	0	1,500
Net cash used in investing activities	-29,216	-21,872
CASH FLOWS FROM FINANCING ACTIVITIES:	'	'
Issuance of common stock under employee stock plans	7,045	8,705
Payments of dividends to stockholders	-3,033	-2,310
Net cash provided by financing activities	4,012	6,395
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	-8,961	6,095
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	92,928	63,394
CASH AND CASH EQUIVALENTS AT END OF PERIOD	83,967	69,489
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES:	'	'
Unpaid property and equipment	4,602	1,469
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:	'	'
Cash refund for income taxes, net of payments	($1,942)	($3,698)

BASIS_OF_PRESENTATION

BASIS OF PRESENTATION	3 Months Ended
	Mar. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
BASIS OF PRESENTATION [Text Block]	'
	BASIS OF PRESENTATION:
	The condensed consolidated financial statements include the accounts of Power Integrations, Inc., a Delaware corporation (the “Company”), and its wholly owned subsidiaries. Significant intercompany accounts and transactions have been eliminated in consolidation.
	While the financial information furnished is unaudited, the condensed consolidated financial statements included in this report reflect all adjustments (consisting only of normal recurring adjustments) that the Company considers necessary for the fair presentation of the results of operations for the interim periods covered and the financial condition of the Company at the date of the interim balance sheet in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The results for interim periods are not necessarily indicative of the results for the entire year. The condensed consolidated financial statements should be read in conjunction with the Power Integrations, Inc. consolidated financial statements and the notes thereto for the year ended December 31, 2013, included in its Form 10-K filed on February 13, 2014, with the Securities and Exchange Commission.

SUMMARY_OF_SIGNIFICANT_ACCOUNT

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
SUMMARY OF SIGNIFICANT ACCOUTING POLICIES [Text Block]	'
	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES:
	No material changes have been made to the Company's significant accounting policies disclosed in Note 2, Summary of Significant Accounting Policies, in its Annual Report on Form 10-K, filed on February 13, 2014, for the year ended December 31, 2013. The accounting policy information below is to aid in the understanding of the financial information disclosed.
	Cash and Cash Equivalents
	The Company considers cash invested in highly liquid financial instruments with maturities of three months or less at the date of purchase to be cash equivalents.
	Marketable Securities
	The Company generally holds securities until maturity; however, they may be sold under certain circumstances including, but not limited to, when necessary for the funding of acquisitions and other strategic investments. As a result the Company classifies its investment portfolio as available-for-sale. The Company classifies all investments with an original maturity date greater than three months as short-term investments in its Condensed Consolidated Balance Sheet. As of March 31, 2014, and December 31, 2013, the Company's marketable securities consisted primarily of highly liquid corporate securities, commercial paper and other high-quality commercial securities.
	Amortized cost and estimated fair market value of investments classified as available-for-sale at March 31, 2014, are as follows (in thousands):
		Amortized			Gross Unrealized							Estimated Fair
		Cost			Gains			Losses				Market Value
	Investments due in less than 3 months:
	Commercial paper	$	3,722		$	1		$	—			$	3,723
	Total	$	3,722		$	1		$	—			$	3,723
	Investments due in 4-12 months:
	Corporate securities	$	16,502		$	63		$	—			$	16,565
	Total	$	16,502		$	63		$	—			$	16,565
	Investments due between 12 months and 5-years:
	Corporate securities	$	116,826		$	300		$	(7	)		$	117,119
	Total	$	116,826		$	300		$	(7	)		$	117,119
	Total investment securities	$	137,050		$	364		$	(7	)		$	137,407
	Amortized cost and estimated fair market value of investments classified as available-for-sale at December 31, 2013, are as follows (in thousands):
		Amortized			Gross Unrealized							Estimated Fair
		Cost			Gains			Losses				Market Value
	Investments due in less than 3 months:
	Commercial paper	$	3,098		$	1		$	—			$	3,099
	Total	$	3,098		$	1		$	—			$	3,099
	Investments due in 4-12 months:
	Corporate securities	$	6,007		$	33		$	—			$	6,040
	Total	$	6,007		$	33		$	—			$	6,040
	Investments due between 12 months and 5-years:
	Corporate securities	$	102,963		$	202		$	(26	)		$	103,139
	Total	$	102,963		$	202		$	(26	)		$	103,139
	Total investment securities	$	112,068		$	236		$	(26	)		$	112,278
	As of March 31, 2014 and December 31, 2013, the Company evaluated the nature of the investments with a loss position which were primarily high-quality corporate securities, and determined the unrealized losses were not other-than-temporary.
	Revenue Recognition
	Product revenues consist of sales to original equipment manufacturers (“OEMs”), merchant power supply manufacturers and distributors. Approximately 75% of the Company's net product sales were made to distributors in the three months ended March 31, 2014, and 75% in the twelve months ended December 31, 2013. The Company applies the provisions of Accounting Standard Codification (“ASC”) 605-10 (“ASC 605-10”) and all related appropriate guidance. Revenue is recognized when all of the following criteria have been met: (1) persuasive evidence of an arrangement exists, (2) delivery has occurred, (3) the price is fixed or determinable, and (4) collectability is reasonably assured. Customer purchase orders are generally used to determine the existence of an arrangement. Delivery is considered to have occurred when title and risk of loss have transferred to the Company's customer. The Company evaluates whether the price is fixed or determinable based on the payment terms associated with the transaction and whether the sales price is subject to refund or adjustment. With respect to collectability, the Company performs credit checks for new customers and performs ongoing evaluations of its existing customers' financial condition and requires letters of credit whenever deemed necessary.
	Sales to international OEM customers and merchant power supply manufacturers that are shipped from the Company's facility in California are pursuant to “delivered at frontier” (“DAF”) shipping terms. As such, title to the product passes to the customer when the shipment reaches the destination country and revenue is recognized upon the arrival of the product in that country. Sales to international OEMs and merchant power supply manufacturers for shipments from the Company's facility outside of the United States are pursuant to “EX Works” ("EXW") shipping terms, meaning that title to the product transfers to the customer upon shipment from the Company's foreign warehouse. Shipments to OEMs and merchant power supply manufacturers in the Americas are pursuant to “free on board” (“FOB”) point of origin shipping terms meaning that title is passed to the customer upon shipment. Revenue is recognized upon title transfer for sales to OEMs and merchant power supply manufacturers, assuming all other criteria for revenue recognition are met.
	Sales to most of the Company's distributors are made under terms allowing certain price adjustments and rights of return on the Company's products held by its distributors. As a result of these rights, the Company defers the recognition of revenue and the costs of revenues derived from sales to distributors until the Company's distributors report that they have sold the Company's products to their customers. The Company's recognition of such distributor revenue is based on point of sale reports received from the distributors, at which time the price is no longer subject to adjustment and is fixed, and the products are no longer subject to return to the Company except pursuant to warranty terms. The gross profit that is deferred as a result of this policy is reflected as “deferred income on sales to distributors” in the accompanying condensed consolidated balance sheets. The total deferred revenue as of March 31, 2014, and December 31, 2013, was approximately $29.2 million and $25.5 million, respectively. The total deferred cost as of March 31, 2014, and December 31, 2013, was approximately $11.3 million and $9.8 million, respectively.
	Frequently, distributors need to sell at a price lower than the standard distribution price in order to win business. At or soon after the distributor invoices its customer, the distributor submits a “ship and debit” price adjustment claim to the Company to adjust the distributor's cost from the standard price to the pre-approved lower price. After verification by the Company, a credit memo is issued to the distributor for the ship and debit claim. The Company maintains a reserve for unprocessed claims and future ship and debit price adjustments. The reserve appears as a reduction to accounts receivable in the Company's accompanying consolidated balance sheets. To the extent future ship and debit claims significantly exceed amounts estimated, there could be a material impact on the deferred revenue and deferred margin ultimately recognized. To evaluate the adequacy of its reserves, the Company analyzes historical ship and debit payments and levels of inventory in the distributor channels.
	Sales to certain distributors of the Company are made under terms that do not include rights of return or price concessions after the product is shipped to the distributor. Accordingly, product revenue is recognized upon shipment and title transfer assuming all other revenue recognition criteria are met.
	Common Stock Repurchases and Cash Dividend
	In October 2012, the Company's board of directors authorized the use of $50 million for the repurchase of the Company's common stock, with repurchases to be executed according to pre-defined price/volume guidelines set by the board of directors. As of March 31, 2014, the Company had $29.5 million available for future stock repurchases. The Company did not purchase shares in the three-month periods ended March 31, 2014 and 2013, as the price of the Company’s stock exceeded the maximum price set forth in the guidelines mentioned above. Authorization of future stock repurchase programs is at the discretion of the board of directors and will depend on the Company's financial condition, results of operations, capital requirements, business conditions and other factors.
	In January 2013, the Company's board of directors declared quarterly cash dividend payments in the amount of $0.08 per share to be paid to stockholders of record at the end of each quarter in 2013. Dividend payouts totaling approximately $2.3 million each were paid on March 29, 2013 and June 28, 2013, and approximately $2.4 million was paid on each of September 30, 2013 and December 31, 2013.
	In October 2013, the Company's board of directors declared four quarterly cash dividends in the amount of $0.10 per share to be paid to stockholders of record at the end of each quarter in 2014. In April 2014, the board of directors declared that the payouts for the third and fourth quarters of 2014 shall increase to $0.12 per share. The first quarterly dividend payout, totaling approximately $3.0 million, was paid on March 31, 2014. The declaration of any future cash dividend is at the discretion of the board of directors and will depend on the Company's financial condition, results of operations, capital requirements, business conditions and other factors, as well as a determination that cash dividends are in the best interests of the Company's stockholders.
	Use of Estimates
	The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. On an ongoing basis, the Company evaluates its estimates, including those related to revenue recognition, income tax, stock-based compensation and inventories. These estimates are based on historical facts and various other assumptions that the Company believes to be reasonable at the time the estimates are made.
	Components of the Company's Condensed Consolidated Balance Sheet
	Accounts Receivable (in thousands):
		March 31,			December 31,
		2014			2013
	Accounts receivable trade	$	47,842		$	42,410
	Accrued ship and debit and rebate claims	(31,316		)	(29,901		)
	Allowance for doubtful accounts	(105		)	(120		)
	Total	$	16,421		$	12,389
	Prepaid Expenses and Other Current Assets (in thousands):
		March 31,			December 31,
		2014			2013
	Prepaid legal fees	$	5,129		$	6,267
	Prepaid income tax	4,048			7,521
	Prepaid maintenance agreements	725			947
	Interest receivable	678			519
	Supplier prepayment	1,511			757
	Other	4,936			2,621
	Total	$	17,027		$	18,632
Changes in accumulated other comprehensive income (loss) for the three months ended March 31, 2014 (in thousands):
	Unrealized Gains and Losses on Available-for-Sale Securities			Defined Benefit Pension Items				Foreign Currency Items				Total
Beginning balance at December 31, 2013	$	210		$	(780	)		$	100			$	(470	)
Other comprehensive income (loss) before reclassifications	147			—				(6		)		141
Amounts reclassified from accumulated other comprehensive income (loss)	—			14			-1	—				14
Net-current period other comprehensive income (loss)	147			14				(6		)		155
Ending balance at March 31, 2014	$	357		$	(766	)		$	94			$	(315	)
____________________________
(1) This component of accumulated other comprehensive income is included in the computation of net periodic pension cost for the three months ended March 31, 2014.
Changes in accumulated other comprehensive income (loss) for the quarter ended March 31, 2013 (in thousands):
	Unrealized Gains and Losses on Available-for-Sale Securities			Defined Benefit Pension Items				Foreign Currency Items				Total
Beginning balance at December 31, 2012	$	138		$	(560	)		$	129			$	(293	)
Other comprehensive income before reclassifications	(54		)	—				(151		)		(205		)
Amounts reclassified from accumulated other comprehensive income	—			14			-1	—				14
Net-current period other comprehensive income	(54		)	14				(151		)		(191		)
Ending balance at March 31, 2013	$	84		$	(546	)		$	(22	)		$	(484	)
____________________________
(1) This component of accumulated other comprehensive income is included in the computation of net periodic pension cost for the three months ended March 31, 2013.

STOCK_PLANS_AND_SHAREBASED_COM

STOCK PLANS AND SHARE-BASED COMPENSATION	3 Months Ended
	Mar. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
STOCK PLANS AND SHARE-BASED COMPENSATION [Text Block]	'
	STOCK PLANS AND SHARE-BASED COMPENSATION:
	Stock Plans
	As of March 31, 2014, the Company had two stock-based compensation plans (the “Plans”) which are described below.
	2007 Equity Incentive Plan
	The 2007 Equity Incentive Plan (the "2007 Plan") was adopted by the board of directors on September 10, 2007, and approved by the stockholders on November 7, 2007, as an amendment and restatement of the 1997 Stock Option Plan (the "1997 Plan").  The 2007 Plan provides for the grant of incentive stock options, nonstatutory stock options, restricted stock awards, restricted stock unit awards ("RSUs"), stock appreciation rights, performance-based awards ("PSUs"), long-term performance based awards ("PRSUs") and other stock awards to employees, directors and consultants. As of March 31, 2014, the maximum remaining number of shares that may be issued under the 2007 Plan was 6,870,264 shares, which includes options granted but not exercised and awards granted but unvested and shares remaining available for issuance under the 1997 Plan, including shares subject to outstanding options and stock awards under the 1997 Plan.  Pursuant to the 2007 Plan, the exercise price for incentive stock options and nonstatutory stock options is generally at least 100% of the fair market value of the underlying shares on the date of grant.  Options generally vest over 48 months measured from the date of grant. Options generally expire no later than ten years after the date of grant, subject to earlier termination upon an optionee's cessation of employment or service.
	Beginning January 27, 2009, grants pursuant to the Directors Equity Compensation Program (that was adopted by the board of directors on January 27, 2009) to nonemployee directors have been made primarily under the 2007 Plan. The Directors Equity Compensation Program provides for grants to outside directors as follows: effective annually, upon the first trading day of July, each outside director would receive a grant of an equity award with an aggregate value of $100,000, which will become exercisable or vest immediately prior to the Company's next year Annual Meeting of Stockholders, subject to the director's continued service.  At each outside director's election, such award would consist entirely of RSUs or entirely of stock options.  The quantity of options would be calculated by dividing $100,000 by the Black-Scholes value on the date of grant. The quantity of RSUs issued would be calculated by dividing $100,000 by the grant date fair value.  Further, on the date of election of a new outside director, such new director would receive such grant as continuing outside directors receive on the first trading day of July; provided, however, that such grant is prorated for the portion of the year that such new outside director will serve until the next first trading day of July.  The Directors Equity Compensation Program will remain in effect at the discretion of the board of directors or the compensation committee of the board.
	On July 28, 2009, the 2007 Plan was amended generally to prohibit outstanding options or stock appreciation rights from being cancelled in exchange for cash without stockholder approval.
	1997 Employee Stock Purchase Plan
	Under the 1997 Employee Stock Purchase Plan (the “Purchase Plan”), eligible employees may apply accumulated payroll deductions, which may not exceed 15% of an employee's compensation, to the purchase of shares of the Company's common stock at periodic intervals. The purchase price of stock under the Purchase Plan is equal to 85% of the lower of (i) the fair market value of the Company's common stock on the first day of each offering period, or (ii) the fair market value of the Company's common stock on the purchase date (as defined in the Purchase Plan). Each offering period consists of one purchase period of approximately six months duration. An aggregate of 3,000,000 shares of common stock were reserved for issuance to employees under the Purchase Plan. As of March 31, 2014, 2,646,861 shares had been purchased and 353,139 shares were reserved for future issuance under the Purchase Plan.
	Stock-Based Compensation
	The Company applies the provisions of ASC 718-10. Under the provisions of ASC 718-10, the Company recognizes the fair value of stock-based compensation in financial statements over the requisite service period of the individual grants, which generally equals a four-year vesting period. The Company uses estimates of volatility, expected term, risk-free interest rate, dividend yield and forfeitures in determining the fair value of these awards and the amount of compensation expense to recognize. The Company uses the straight-line method to amortize all stock awards granted over the requisite service period of the award, and uses historical data to estimate pre-vesting forfeitures, recognizing expense only for those awards that are expected to vest.
	Determining Fair Value of Stock Options
	The Company uses the Black-Scholes valuation model for valuing stock option grants using the following assumptions and estimates:
	Expected Volatility. The Company calculates expected volatility based on the historical price volatility of the Company's stock.
	Expected Term. The Company utilizes a model which uses historical exercise, cancellation and outstanding option data to calculate the expected term of stock option grants.
	Risk-Free Interest Rate. The Company bases the risk-free interest rate used in the Black-Scholes valuation model on the implied yield available on a U.S. Treasury note with a term approximately equal to the expected term of the underlying grants.
	Dividend Yield.  The dividend yield was calculated by dividing the annual dividend by the average closing price of the Company's common stock on a quarterly basis.
	The following table summarizes the stock-based compensation expense recognized in accordance with ASC 718-10 for the three months ended March 31, 2014, and March 31, 2013 (in thousands).
		Three Months Ended
		March 31,
		2014				2013
	Cost of revenues	$	219			$	264
	Research and development	1,212				1,106
	Sales and marketing	935				829
	General and administrative	1,549				1,437
	Total stock-based compensation expense	$	3,915			$	3,636
	Stock compensation expense in the three months ended March 31, 2014, was $3.9 million (comprising approximately $0.5 million related to stock options, $0.5 million related to performance-based awards, $2.6 million related to restricted stock units and $0.3 million related to the Purchase Plan). Stock compensation expense in the three months ended March 31, 2013, was $3.6 million (comprising approximately $1.0 million related to stock options, $0.4 million related to performance-based awards, $1.9 million related to restricted stock units and $0.3 million related to the Purchase Plan).
	The following table summarizes total compensation expense related to unvested awards not yet recognized, net of expected forfeitures, and the weighted-average period over which it is expected to be recognized as of March 31, 2014.
		March 31, 2014
		Unrecognized					Weighted Average
		Compensation					Remaining
		Expense for Unvested					Recognition
		Awards					Period
		(In thousands)					(In years)
	Options		$	1,497				1.44
	Performance-based awards		1,706					0.75
	Long term performance-based awards		2,156					2.75
	Restricted stock units		20,511					2.38
	Purchase plan		396					0.5
	Total unrecognized compensation expense		$	26,266
	The Company did not grant stock options in the three months ended March 31, 2014 or March 31, 2013, and therefore no fair-value assumptions were reported for those periods.
	The fair value of employees’ stock purchase rights under the Purchase Plan was estimated using the Black-Scholes model with the following weighted-average assumptions:
		Three Months Ended
		March 31,
		2014		2013
	Risk-free interest rates	0.07%		0.11%
	Expected volatility rates	30%		33%
	Expected dividend yield	0.66%		0.80%
	Expected term of purchase right (in years)	0.5		0.5
	Weighted-average estimated fair value of purchase rights	$13.31		$9.14
	A summary of stock option activity under the Plans, excluding performance-based awards and restricted stock units, as of March 31, 2014, and changes during the three months then ended is presented below:
		Shares			Weighted-			Weighted-Average		Aggregate
		(in thousands)			Average			Remaining		Intrinsic Value
					Exercise			Contractual		(in thousands)
					Price			Term
								(in years)
	Outstanding at January 1, 2014	1,691			$27.34
	Granted	—			—
	Exercised	(176	)		$27.26
	Forfeited or expired	—			—
	Outstanding at March 31, 2014	1,515			$27.35			4.3		$	58,210
	Exercisable at March 31, 2014	1,400			$26.29			4.03		$	55,288
	Vested and expected to vest at March 31, 2014	1,512			$27.32			4.29		$	58,145
The Company did not grant stock options in the three months ended March 31, 2014 and March 31, 2013. Since 2010 the Company's equity grants to new hires and its annual incentive grants to non-executive employees have been primarily in the form of RSUs. The total intrinsic value of options exercised during the three months ended March 31, 2014 and 2013, was approximately $5.8 million and $5.2 million, respectively.
Performance-based Awards ("PSUs")
Under the performance-based awards program, the Company grants awards in the first half of the performance year in an amount equal to twice the target number of shares to be issued if the target performance metrics are met. The number of shares that are released at the end of the performance year can range from zero to 200% of the targeted number depending on the Company's performance. In 2014, the performance metrics of this program are annual targets consisting of net revenue and non-GAAP operating earnings. Each performance-based award granted from the 2007 Plan will reduce the number of shares available for issuance under the 2007 Plan by 2.0 shares.
During the three months ended March 31, 2014, the Company granted approximately 44,000 annual performance-based awards. As the net revenue and non-GAAP operating earnings are considered performance conditions, expenses associated with these awards, net of estimated forfeitures, are recorded throughout the year depending on the number of shares expected to be earned based on progress toward the performance targets. The cost of performance-based awards is determined using the fair value of the Company's common stock on the grant date, reduced by the discounted present value of dividends expected to be declared before the awards vest. If the performance conditions are not achieved, no compensation cost is recognized and any previously recognized compensation is reversed.
In January 2014, it was determined that approximately 83,000 shares of the approximately 100,000 performance-based awards granted in 2013, less forfeitures, vested in aggregate. The 2013 performance metrics consisted of revenue, non-GAAP operating income and strategic-goals for such awards. Accordingly, 83,000 performance-based awards were released to the Company's employees and executives in the first quarter of 2014.
A summary of performance-based awards outstanding as of March 31, 2014, and activity during the three months then ended, is presented below:
	Shares			Weighted- Average Grant Date Fair Value Per Share			Weighted-Average Remaining Contractual Term		Aggregate Intrinsic Value
	(in thousands)						(in years)		(in thousands)
Outstanding at January 1, 2014	100			$38.48
Granted	44			$58.55
Vested	(83	)		$38.48
Change in units due to performance achievement for PSUs vested in the year	(17	)		$38.48
Forfeited or expired	—			—
Outstanding at March 31, 2014	44			$58.55			0.75		$	2,868
Outstanding and expected to vest at March 31, 2014	37						0.75		$	2,466
The weighted-average grant-date fair value per share of performance-based awards granted in the three months ended March 31, 2014 and 2013 was approximately $58.55, and $36.43, respectively. The grant-date fair value of awards released, which were fully vested, in the three months ended March 31, 2014 and 2013, was approximately $3.2 million and $2.0 million, respectively.
Long-Term Performance-based Awards ("PRSUs")
The Company's PRSU program provides for the issuance of PRSUs which will vest based on Company performance measured against the 2014 PRSU Plan's established 2016 revenue target. The PRSUs were granted in an amount equal to twice the target number of shares to be issued if the target performance metric is met. The actual number of shares the recipient receives is determined at the end of a three-year performance period based on results achieved versus the Company's performance goal, and may range from zero to 200% of the targeted number. The performance goal for PRSUs granted in fiscal 2014 was based on the Company's adjusted annual revenue growth. Each long-term performance-based award granted from the 2007 Plan will reduce the number of shares available for issuance under the 2007 Plan by 2.0 shares.
Recipients of a PRSU award generally must remain employed by the Company on a continuous basis through the end of the applicable three-year performance period in order to receive shares subject to that award. Expenses associated with these awards, net of estimated forfeitures, are recorded throughout the year depending on the number of shares expected to be earned based on progress toward the performance target. The cost of long-term performance-based awards is determined using the fair value of the Company's common stock on the grant date, reduced by the discounted present value of dividends expected to be declared before the awards vest. If the performance conditions are not achieved, no compensation cost is recognized and any previously recognized compensation is reversed.
A summary of long-term performance-based awards outstanding as of March 31, 2014, and activity during the three months then ended, is presented below:
	Shares			Weighted- Average Grant Date Fair Value Per Share			Weighted-Average Remaining Contractual Term		Aggregate Intrinsic Value
	(in thousands)						(in years)		(in thousands)
Outstanding at January 1, 2014	—			—
Granted	47			$57.76
Vested	—			—
Forfeited or expired	—			—
Outstanding at March 31, 2014	47			$57.76			2.75		$	3,072
Outstanding and expected to vest at March 31, 2014	40						2.75		$	2,629
Restricted Stock Units (RSUs)
The Company grants restricted stock units to employees under the 2007 Plan. RSUs granted to employees typically vest ratably over a four-year period, and are converted into shares of the Company's common stock upon vesting on a one-for-one basis subject to the employee's continued service with the Company over that period. The fair value of RSUs is determined using the fair value of the Company's common stock on the date of the grant, reduced by the discounted present value of dividends expected to be declared before the awards vest. Compensation expense is recognized on a straight-line basis over the requisite service period of each grant adjusted for estimated forfeitures. Each RSU award granted from the 2007 plan will reduce the number of shares available for issuance under the 2007 Plan by 2.0 shares.
A summary of RSUs outstanding as of March 31, 2014, and changes during the three months then ended, are as follows:
	Shares			Weighted- Average Grant Date Fair Value Per Share		Weighted-Average Remaining Contractual Term		Aggregate Intrinsic Value
	(in thousands)					(in years)		(in thousands)
Outstanding at January 1, 2014	714			$38.97
Granted	86			$57.05
Vested	(46	)		$35.93
Forfeited or expired	(4	)		$39.47
Outstanding at March 31, 2014	750			$41.21		1.44		$	49,312
Outstanding and expected to vest at March 31, 2014	704					1.34		$	46,280
The weighted-average grant-date fair value per share of RSUs awarded in the three months ended March 31, 2014 and 2013 was approximately $57.05 and $35.68, respectively. The grant-date fair value of RSUs vested in the three months ended March 31, 2014 and 2013, was approximately $1.6 million and $0.2 million, respectively.

FAIR_VALUE_MEASUREMENTS

FAIR VALUE MEASUREMENTS	3 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
FAIR VALUE MEASUREMENTS [Text Block]	'
	FAIR VALUE MEASUREMENTS:
	ASC 820-10, Fair Value Measurements, clarifies that fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, ASC 820-10 establishes a three-tier value hierarchy, which prioritizes the inputs used in measuring fair value as follows: (Level 1) observable inputs such as quoted prices for identical assets in active markets; (Level 2) inputs other than the quoted prices in active markets that are observable either directly or indirectly; and (Level 3) unobservable inputs in which there is little or no market data, which requires the Company to develop its own assumptions. This hierarchy requires the Company to use observable market data, when available, and to minimize the use of unobservable inputs when determining fair value.
	The Company's cash and investment instruments are classified within Level 1 or Level 2 of the fair-value hierarchy because they are valued using quoted market prices, broker or dealer quotations, or alternative pricing sources with reasonable levels of price transparency. The type of instrument valued based on quoted market prices in active markets primarily includes money market securities. This type of instrument is generally classified within Level 1 of the fair-value hierarchy. The types of instruments valued based on other observable inputs (Level 2 of the fair-value hierarchy) include investment-grade corporate bonds and government, state, municipal and provincial obligations. Such types of investments are valued by using a multi-dimensional relational model, the inputs are primarily benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, and reference data including market research publications. The Company principally holds securities until maturity; however, they may be sold under certain circumstances, including, but not limited to, the funding of acquisitions and other strategic investments. As a result the Company classified its investment portfolio as available-for-sale. The Company's investments classified as Level 1 and Level 2 are available-for-sale investments, and were recorded at fair market value.
	The fair-value hierarchy of the Company's marketable securities at March 31, 2014, and December 31, 2013, was as follows (in thousands):
		Fair Value Measurement at
		March 31, 2014
	Description	March 31, 2014		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)
	Commercial paper	$	3,723	$	—	$	3,723
	Money market funds	17,516		17,516		—
	Corporate securities	133,684		—		133,684
	Total	$	154,923	$	17,516	$	137,407
		Fair Value Measurement at
		December 31, 2013
	Description	December 31, 2013		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)
	Commercial paper	$	3,099	$	—	$	3,099
	Money market funds	17,492		17,492		—
	Corporate securities	109,179		—		109,179
	Total	$	129,770	$	17,492	$	112,278
	The Company did not transfer any investments between Level 1 and Level 2 of the fair-value hierarchy in the three months ended March 31, 2014, and the twelve months ended December 31, 2013.

INVENTORIES

INVENTORIES	3 Months Ended
	Mar. 31, 2014
Inventory Disclosure [Abstract]	'
INVENTORIES [Text Block]	'
	INVENTORIES:
	Inventories (which consist of costs associated with the purchases of wafers from domestic and offshore foundries and of packaged components from offshore assembly manufacturers, as well as internal labor and overhead associated with the testing of both wafers and packaged components) are stated at the lower of cost (first-in, first-out) or market. Provisions, when required, are made to reduce excess and obsolete inventories to their estimated net realizable values. Inventories consist of the following (in thousands):
		March 31,		December 31,
		2014		2013
	Raw materials	$	11,257	$	8,221
	Work-in-process	12,207		13,216
	Finished goods	24,470		20,798
	Total	$	47,934	$	42,235

GOODWILL_AND_INTANGIBLE_ASSETS

GOODWILL AND INTANGIBLE ASSETS	3 Months Ended
	Mar. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
GOODWILL AND INTANGIBLE ASSETS [Text Block]	'
	GOODWILL AND INTANGIBLE ASSETS:
	There were no changes in the carrying amount of goodwill during the three months ended March 31, 2014.
	Intangible assets consist primarily of developed technology, acquired licenses, customer relationships, trade name, in-process research and development and patent rights, and are reported net of accumulated amortization. The Company amortizes the cost of all intangible assets over the shorter of the estimated useful life or the term of the developed technology, acquired licenses, customer relationships, trade name and patent rights, which range from two to 12 years, with the exception of $4.7 million of in-process research and development. In-process research and development is assessed for impairment until the development is completed and products are available for sale, at which time the Company will begin to amortize the in-process research and development. The Company does not expect the amortization of in-process research and development to begin in 2014. Amortization for acquired intangible assets was approximately $1.9 million and $1.8 million in the three months ended March 31, 2014 and 2013, respectively. The Company does not believe there is any significant residual value associated with the following intangible assets:
		March 31, 2014								December 31, 2013
		Gross			Accumulated			Net		Gross		Accumulated			Net
					Amortization							Amortization
		(in thousands)
	In-process research and development	$	4,690		$	—		$	4,690	$	4,690	$	—		$	4,690
	Technology licenses	3,000			(2,400		)	600		3,000		(2,325		)	675
	Patent rights	1,949			(1,949		)	—		1,949		(1,949		)	—
	Developed technology	26,670			(5,893		)	20,777		26,670		(5,247		)	21,423
	Customer relationships	17,610			(5,349		)	12,261		17,610		(4,664		)	12,946
	Trade name	3,600			(3,450		)	150		3,600		(3,000		)	600
	Total intangible assets	$	57,519		$	(19,041	)	$	38,478	$	57,519	$	(17,185	)	$	40,334
	The estimated future amortization expense related to intangible assets at March 31, 2014, is as follows:
	Fiscal Year		Estimated
			Amortization
			(in  thousands)
	2014	(remaining 9 months)	$	4,216
	2015		5,009
	2016		4,394
	2017		3,994
	2018		3,746
	Thereafter		12,429
	Total (1)		$	33,788
	_______________
	-1	The total above excludes $4.7 million of in-process research and development that will be amortized upon completion of development over the estimated useful life of the technology.

SIGNIFICANT_CUSTOMERS_AND_EXPO

SIGNIFICANT CUSTOMERS AND EXPORT SALES	3 Months Ended
	Mar. 31, 2014
Risks and Uncertainties [Abstract]	'
SIGNIFICANT CUSTOMERS AND EXPORT SALES [Text Block]	'
	SIGNIFICANT CUSTOMERS AND INTERNATIONAL SALES:
	Segment Reporting
	The Company is organized and operates as one reportable segment, the design, development, manufacture and marketing of integrated circuits and related components for use primarily in the high-voltage power-conversion market. The Company's chief operating decision maker, the Chief Executive Officer, reviews financial information presented on a consolidated basis for purposes of making operating decisions and assessing financial performance.
	Customer Concentration
	Ten customers accounted for approximately 59% and 58% of net revenues for the three months ended March 31, 2014 and 2013, respectively. A significant portion of these revenues are attributable to sales of the Company’s products to distributors of electronic components. These distributors sell the Company’s products to a broad, diverse range of end users, including OEMs and merchant power supply manufacturers.
	Customers representing 10% or more of total net revenues are as follows:
		Three Months Ended
		March 31,
	Customer	2014		2013
	A	19	%	19	%
	B	*		10	%
	____________________
	* Total customer revenue was less than 10% of net revenues.
	Customers A and B are distributors of the Company's products. No other customers accounted for 10% or more of the Company's net revenues in the periods mentioned.
	Concentration of Credit Risk
	Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash investments and trade receivables. The Company has cash investment policies that limit cash investments to low-risk investments. With respect to trade receivables, the Company performs ongoing evaluations of its customers' financial conditions and requires letters of credit whenever deemed necessary. Additionally, the Company establishes an allowance for doubtful accounts based upon factors surrounding the credit risk of specific customers, historical trends related to past write-offs and other relevant information. Account balances are charged off against the allowance after all means of collection have been exhausted and the potential for recovery is considered remote. The Company does not have any off-balance-sheet credit exposure related to its customers. As of March 31, 2014, and December 31, 2013, 67% and 71%, respectively, of accounts receivable were concentrated with the Company's top 10 customers.
	The following customers represented 10% or more of accounts receivable:
	Customer	March 31,		December 31,
		2014		2013
	Avnet	27	%	21	%
	ATM Electronic Corporation	11	%	17	%
	Customers A and B are distributors of the Company’s products. No other customers accounted for 10% or more of the Company’s accounts receivable in these periods.
	International Sales
	The Company markets its products globally through its sales personnel and a worldwide network of independent sales representatives and distributors. As a percentage of total net revenues, international sales, which consist of domestic and foreign sales to distributors and direct customers outside of the United States of America, comprise the following:
		Three Months  Ended
		March 31,
		2014		2013
	Hong Kong/China	44	%	44	%
	Taiwan	16	%	15	%
	Korea	11	%	13	%
	Western Europe (excluding Germany)	11	%	12	%
	Japan	6	%	5	%
	Singapore	2	%	3	%
	Germany	2	%	2	%
	Other	3	%	1	%
	Total foreign revenue	95	%	95	%
	The remainder of the Company’s sales is to customers within the United States of America.
	Product Sales
	Net revenues consist primarily of sales of the Company's high-voltage integrated-circuit products, IGBT drivers and high-voltage silicon diodes. When evaluating the Company's net revenues, the Company categorizes its sales into the following four major end-market categories; communications, computer, consumer and industrial. The table below provides the percentage of net sales activity by end markets served on a comparative basis for the three months ended March 31, 2014 and 2013:
		Three Months Ended
		March 31,
	End Market	2014		2013
	Communications	18	%	22	%
	Computer	10	%	10	%
	Consumer	37	%	36	%
	Industrial	35	%	32	%

EARNINGS_PER_SHARE

EARNINGS PER SHARE	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Abstract]	'
EARNINGS PER SHARE [Text Block]	'
	EARNINGS PER SHARE:
	Basic earnings per share are calculated by dividing net income by the weighted-average shares of common stock outstanding during the period. Diluted earnings per share are calculated by dividing net income by the weighted-average shares of common stock and dilutive common equivalent shares outstanding during the period. Dilutive common equivalent shares included in this calculation consist of dilutive shares issuable upon the assumed exercise of outstanding common stock options, the assumed vesting of outstanding restricted stock units and both short- and long-term performance-based awards, and the assumed issuance of awards under the stock purchase plan, as computed using the treasury stock method.
	A summary of the earnings per share calculation is as follows (in thousands, except per share amounts):
		Three Months Ended
		March 31,
		2014		2013
	Basic earnings per share:
	Net income	$	12,363	$	10,903
	Weighted-average common shares	30,239		28,754
	Basic earnings per share	$	0.41	$	0.38
	Diluted earnings per share (1):
	Net income	$	12,363	$	10,903
	Weighted-average common shares	30,239		28,754
	Effect of dilutive securities:
	Employee stock plans	928		1,029
	Diluted weighted-average common shares	31,167		29,783
	Diluted earnings per share	$	0.4	$	0.37
	_______________
	-1	The Company includes the shares underlying performance-based awards in the calculation of diluted earnings per share if the performance conditions have been satisfied as of the end of the reporting period and excludes such shares when the necessary conditions have not been met. The Company has excluded the shares underlying the 2014 and 2013 awards in the 2014 and 2013 calculation, respectively, as those shares were not contingently issuable as of the end of the period.
	In the three months ended March 31, 2014, all shares were included in the computation of diluted earnings per share as none were determined to be anti-dilutive, and in 2013, 281,973 shares were not included in the computation of diluted earnings per share for the period then ended because they were determined to be anti-dilutive.

PROVISION_FOR_INCOME_TAXES

PROVISION FOR INCOME TAXES	3 Months Ended
	Mar. 31, 2014
Income Tax Disclosure [Abstract]	'
PROVISION FOR INCOME TAXES [Text Block]	'
	PROVISION FOR INCOME TAXES:
	The Company accounts for income taxes under the provisions of ASC 740. Under the provisions of ASC 740, deferred tax assets and liabilities are recognized based on the differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, utilizing the tax rates that are expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled.
	In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities and projected future taxable income. In the event that the Company determines, based on available evidence and management judgment, that all or part of the net deferred tax assets will not be realized in the future, the Company would record a valuation allowance in the period the determination is made. In addition, the calculation of tax liabilities involves significant judgment in estimating the impact of uncertainties in the application of complex tax laws. Resolution of these uncertainties in a manner inconsistent with the Company's expectations could have a material impact on its results of operations and financial position.
	As of March 31, 2014, the Company continues to maintain a valuation allowance on capital losses for federal purposes, and on its California deferred tax assets as the Company believes that it is not more likely than not that these deferred tax assets will be fully realized. The Company also maintains a valuation allowance with respect to certain of its deferred tax assets relating to tax credits in Canada.
	Income tax expense includes a provision for (benefit from) federal, state and foreign taxes based on the annual estimated effective tax rate applicable to the Company and its subsidiaries, adjusted for certain discrete items which are fully recognized in the period they occur. The Company's effective tax rates for the three months ended March 31, 2014 and 2013, were 4.8% and (17.3)%, respectively. The difference between the expected statutory rate of 35% and the Company's effective tax rate for the three months ended March 31, 2014, was primarily due to the beneficial impact of the geographic distribution of the Company's world-wide earnings. The difference between the expected statutory rate of 35% and the Company's effective tax rate for the three months ended March 31, 2013, was primarily due to the beneficial impact of the geographic distribution of the Company's world-wide earnings and passage of the American Tax Relief Act of 2012 signed into law on January 2, 2013. The prior year impact of the 2012 Federal research and development tax credit benefit was recorded in the quarter ended March 31, 2013 due to the signing of the law in 2013. The Federal R&D tax credit has not been extended for 2014 as of the end of the first quarter, therefore no Federal R&D tax benefits have been recognized.  If Congress extends the research tax credit there will be a favorable impact on the Company's 2014 effective income tax rate.
	The royalty arrangement between the Company and its foreign subsidiary concluded on October 31, 2012, resulting in a substantially lower effective tax rate for the Company in future years. As a result of the royalty arrangement ending and to ensure an additional source of U.S. cash, the Company plans to repatriate a portion of its current year offshore earnings to the U.S. for domestic operations and accordingly has provided for estimated federal and state income taxes on such earnings. For earnings accumulated as of December 31, 2013 and for the remaining portion of the current year earnings, the Company continues to permanently reinvest such amounts in its foreign jurisdictions, except to the extent there is any previously taxed income which is expected to be repatriated.  If circumstances change and it becomes apparent that some or all of those undistributed earnings of the Company's offshore subsidiary will be remitted in the foreseeable future but income taxes have not been recognized, the Company will accrue income taxes attributable to that remittance.
	Determining the consolidated provision for (benefit from) income tax expense, income tax liabilities and deferred tax assets and liabilities involves judgment. The Company calculates and provides for income taxes in each of the tax jurisdictions in which it operates, which involves estimating current tax exposures as well as making judgments regarding the recoverability of deferred tax assets in each jurisdiction. The estimates used could differ from actual results, which may have a significant impact on operating results in future periods.
	In July 2013, the FASB issued a new accounting standard that requires the presentation of certain unrecognized tax benefits as reductions to deferred tax assets rather than as liabilities in the Company's Condensed Consolidated Balance Sheets when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists. The Company adopted this new standard on a prospective basis in the first quarter of 2014. The impact of the adoption was a reduction to long-term deferred tax assets and non current income tax payable of approximately $4.3 million.

INDEMNIFICATIONS

INDEMNIFICATIONS	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]	'
INDEMNIFICATIONS [Text Block]	'
	INDEMNIFICATIONS:
	The Company sells products to its distributors under contracts, collectively referred to as Distributor Sales Agreements (“DSA”). Each DSA contains the relevant terms of the contractual arrangement with the distributor, and generally includes certain provisions for indemnifying the distributor against losses, expenses, and liabilities from damages that may be awarded against the distributor in the event the Company's products are found to infringe upon a patent, copyright, trademark, or other proprietary right of a third party (“Customer Indemnification”). The DSA generally limits the scope of and remedies for the Customer Indemnification obligations in a variety of industry-standard respects, including, but not limited to, limitations based on time and geography, and a right to replace an infringing product. The Company also, from time to time, has granted a specific indemnification right to individual customers.
	The Company believes its internal development processes and other policies and practices limit its exposure related to such indemnifications. In addition, the Company requires its employees to sign a proprietary information and inventions agreement, which assigns the rights to its employees' development work to the Company. To date, the Company has not had to reimburse any of its distributors or customers for any losses related to these indemnifications and no material claims were outstanding as of March 31, 2014. For several reasons, including the lack of prior indemnification claims and the lack of a monetary liability limit for certain infringement cases, the Company cannot determine the maximum amount of potential future payments, if any, related to such indemnifications.

COMMITMENTS

COMMITMENTS	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]	'
COMMITMENTS [Text Block]	'
	COMMITMENTS:
	Supplier Agreements
	Three of the Company's major suppliers have wafer supply agreements based in U.S. dollars; however, the agreements with two of these foundries, Seiko Epson Corporation, or Epson, and ROHM Lapis Semiconductor Co., Ltd., or Lapis, also allow for mutual sharing of the impact of the exchange rate fluctuation between Japanese yen and the U.S. dollar on future purchases. Each year, the Company's management and these two suppliers review and negotiate future pricing; the negotiated pricing is denominated in U.S. dollars but is subject to contractual exchange rate provisions. The fluctuation in the exchange rate is shared equally between the Company and each of these suppliers on future purchases.

LEGAL_PROCEEDINGS_AND_CONTINGE

LEGAL PROCEEDINGS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]	'
LEGAL PROCEEDINGS AND CONTINGENCIES [Text Block]	'
	LEGAL PROCEEDINGS AND CONTINGENCIES:
	From time to time in the ordinary course of business, the Company becomes involved in lawsuits, or customers and distributors may make claims against the Company. In accordance with ASC 450-10, the Company makes a provision for a liability when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated.
	On October 20, 2004, the Company filed a complaint against Fairchild Semiconductor International, Inc. and Fairchild Semiconductor Corporation (referred to collectively as "Fairchild") in the United States District Court for the District of Delaware. In its complaint, the Company alleged that Fairchild has and is infringing four of Power Integrations' patents pertaining to PWM integrated circuit devices. Fairchild denied infringement and asked for a declaration from the court that it does not infringe any Power Integrations patent and that the patents are invalid. The Court issued a claim construction order on March 31, 2006 which was favorable to the Company. The Court set a first trial on the issues of infringement, willfulness and damages for October 2, 2006. At the close of the first trial, on October 10, 2006, the jury returned a verdict in favor of the Company finding all asserted claims of all four patents-in-suit to be willfully infringed by Fairchild and awarding $34.0 million in damages. Fairchild raised defenses contending that the asserted patents are invalid or unenforceable, and the Court held a second trial on these issues beginning on September 17, 2007. On September 21, 2007, the jury returned a verdict in the Company's favor, affirming the validity of the asserted claims of all four patents-in-suit. Fairchild submitted further materials on the issue of enforceability along with various other post-trial motions, and the Company filed post-trial motions seeking a permanent injunction and increased damages and attorneys' fees, among other things. On September 24, 2008, the Court denied Fairchild's motion regarding enforceability and ruled that all four patents are enforceable. On December 12, 2008, the Court ruled on the remaining post-trial motions, including granting a permanent injunction, reducing the damages award to $6.1 million, granting Fairchild a new trial on the issue of willful infringement in view of an intervening change in the law, and denying the Company's motion for increased damages and attorneys' fees with leave to renew the motion after the resolution of the issue of willful infringement. On December 22, 2008, at Fairchild's request, the Court temporarily stayed the permanent injunction for 90 days. On January 12, 2009, Fairchild filed a notice of appeal challenging the Court's refusal to enter a more permanent stay of the injunction, and Fairchild filed additional motions requesting that both the Federal Circuit and the District Court extend the stay of injunction. The District Court temporarily extended the stay pending the Federal Circuit ruling on Fairchild's pending motion, but the Federal Circuit dismissed Fairchild's appeal and denied its motion on May 5, 2009, and the District Court issued an order on May 13, 2009 confirming the reinstatement of the permanent injunction as originally entered in December 2008. On June 22, 2009, the Court held a brief bench re-trial on the issue of willful infringement. On July 22, 2010, the Court found that Fairchild willfully infringed all four of the asserted patents, and the Court also invited briefing on enhanced damages and attorneys' fees. Fairchild also filed a motion requesting that the Court amend its findings regarding willfulness. On January 18, 2011, the Court denied Fairchild's request to amend the findings regarding Fairchild's willful infringement and doubled the damages award against Fairchild but declined to award attorneys' fees. On February 3, 2011, the Court entered final judgment in favor of the Company for a total damages award of $12.9 million. Fairchild filed a notice of appeal challenging the final judgment and a number of the underlying rulings, and the Company filed a cross-appeal seeking to increase the damages award. The appeal was argued on January 11, 2012, and the Federal Circuit issued a mixed ruling on March 26, 2013, affirming Fairchild's infringement of certain claims that support the basis for the permanent injunction while reversing, vacating, and remanding the findings with respect to other claims, including the Company's claim for damages. The Company filed a petition seeking Supreme Court review of the Federal Circuit’s ruling on damages issues, and the Supreme Court called for a response from Fairchild but ultimately declined to review the case. On remand, the Company intends to pursue its claim for financial compensation based on Fairchild's infringement.
	On May 9, 2005, the Company filed a Complaint with the U.S. International Trade Commission (“ITC”) under section 337 of the Tariff Act of 1930, as amended, 19 U.S.C. section 1337 against System General (“SG”). The Company filed a supplement to the complaint on May 24, 2005. The Company alleged infringement of its patents pertaining to pulse width modulation (“PWM”) integrated circuit devices produced by SG, which are used in power conversion applications such as power supplies for computer monitors. The Commission instituted an investigation on June 8, 2005 in response to the Company's complaint. SG filed a response to the ITC complaint asserting that the patents-in-suit were invalid and not infringed. The Company subsequently and voluntarily narrowed the number of patents and claims in suit, which proceeded to a hearing. The hearing on the investigation was held before the Administrative Law Judge (“ALJ”) from January 18 to January 24, 2006. Post-hearing briefs were submitted and briefing concluded February 24, 2006. The ALJ's initial determination was issued on May 15, 2006. The ALJ found all remaining asserted claims valid and infringed, and recommended the exclusion of the infringing products as well as certain downstream products that contain the infringing products. After further briefing, on June 30, 2006, the Commission decided not to review the initial determination on liability, but did invite briefs on remedy, bonding and the public interest. On August 11, 2006 the Commission issued an order excluding from entry into the United States the infringing SG PWM chips, and any LCD computer monitors, AC printer adapters and sample/demonstration circuit boards containing an infringing SG chip. The U.S. Customs Service is authorized to enforce the exclusion order. On October 11, 2006, the presidential review period expired without any action from the President, and the ITC exclusion order is now in full effect. SG appealed the ITC decision, and on November 19, 2007, the Federal Circuit affirmed the ITC's findings in all respects. On October 27, 2008, SG filed a petition to modify the exclusion order in view of a recent Federal Circuit opinion in an unrelated case, and the Company responded to oppose any modification, but the Commission modified the exclusion order on February 27, 2009. Nevertheless, the exclusion order still prohibits SG and related entities from importing the infringing SG chips and any LCD computer monitors, AC printer adapters, and sample/demonstration circuit boards containing an infringing SG chip.
	On May 23, 2008, the Company filed a complaint against Fairchild Semiconductor International, Inc., Fairchild Semiconductor Corporation, and Fairchild's wholly owned subsidiary System General Corporation in the United States District Court for the District of Delaware. In its complaint, the Company alleged that Fairchild has infringed and is infringing three patents pertaining to power supply controller integrated circuit devices. Fairchild answered the Company's complaint on November 7, 2008, denying infringement and asking for a declaration from the Court that it does not infringe any Power Integrations patent and that the patents are invalid and unenforceable. Fairchild's answer also included counterclaims accusing the Company of infringing three patents pertaining to primary side power conversion integrated circuit devices. Fairchild had earlier brought these same claims in a separate suit against the Company, also in Delaware, which Fairchild dismissed in favor of adding its claims to the Company's already pending suit against Fairchild. The Company has answered Fairchild's counterclaims, denying infringement and asking for a declaration from the Court that it does not infringe any Fairchild patent and that the Fairchild patents are invalid. Fairchild also filed a motion to stay the case, but the Court denied that motion on December 19, 2008. On March 5, 2009, Fairchild filed a motion for summary judgment to preclude any recovery for post-verdict sales of parts found to infringe in the parties' other ongoing litigation, described above, and the Company filed its opposition and a cross-motion to preclude Fairchild from re-litigating the issues of infringement and damages for those same products. On June 26, 2009, the Court held a hearing on the parties' motions, and on July 9, 2009 the Court issued an order denying the parties' motions but staying proceedings with respect to the products that were found to infringe and which are subject to the injunction in the other Delaware case between the parties pending the entry of final judgment in that case; those products are expected to be addressed in the context of the parties’ remand proceedings following the appeal in their earlier litigation in Delaware, and the remainder of the case is proceeding. On December 18, 2009, the Court issued an order construing certain terms in the asserted claims of the Company's and Fairchild's patents in suit. Following the Court's ruling on claim construction, Fairchild withdrew its claim related to one of its patents and significantly reduced the number of claims asserted for the remaining two patents. The parties thereafter filed and argued a number of motions for summary judgment, and the Court denied the majority of the parties' motions but granted the Company's motion to preclude Fairchild from re-arguing validity positions that were rejected in the prior case between the parties. Because the assigned Judge retired at the end of July 2010, the case was re-assigned to a different Judge, and the Court vacated the trial schedule and had the parties provide their input on the appropriate course of action. The Court thereafter set a trial schedule with the jury trial on infringement and validity to begin in July 2011. On April 18, 2011, the Court rescheduled the trial to begin in January 2012, and on June 2, 2011, the Court moved the trial date to April 2012 to permit the parties to address another patent the Company accused Fairchild of infringing. Following a trial in April 2012, the jury returned a verdict finding that Fairchild infringes two of the Company's patents, that Fairchild has induced others to infringe the Company's patents, and also upheld the validity of the infringed patents. Of the two remaining counterclaim patents Fairchild asserted in the case, one was found not to be infringed, but the jury found the second patent to be infringed by a limited number of the Company's products, although the jury further found the Company did not induce infringement by any customers, including customers outside the United States. On March 29, 2013, the District Court denied most of the parties' post-trial motions on liability but granted the Company's motion for judgment as a matter of law finding that Fairchild infringed another of the Company's patents. On April 25, 2013, the Court denied both parties' motions regarding the unenforceability of each other's patents. The Company intends to challenge adverse findings on appeal; nevertheless, the Company estimates that even if the verdict on Fairchild's patent were ultimately upheld, the sales potentially impacted would amount to only about 0.3% of the Company's revenues. The Company has also requested an injunction preventing further infringement of its own patents by Fairchild, and Fairchild has requested an injunction as well; a hearing on the issue is scheduled for June of this year, with a ruling expected in the months to follow. The Company is also seeking financial damages, as well as enhanced damages for willful infringement, issues to be decided in separate proceedings at a later date.
	On June 28, 2004, the Company filed a complaint for patent infringement in the U.S. District Court, Northern District of California, against SG Corporation, a Taiwanese company, and its U.S. subsidiary. The Company's complaint alleged that certain integrated circuits produced by SG infringed and continue to infringe certain of its patents. On June 10, 2005, in response to the initiation of the International Trade Commission (ITC) investigation discussed above, the District Court stayed all proceedings. Subsequent to the completion of the ITC proceedings, the District Court temporarily lifted the stay and scheduled a case management conference. On December 6, 2006, SG filed a notice of appeal of the ITC decision as discussed above. In response, and by agreement of the parties, the District Court vacated the scheduled case management conference and renewed the stay of proceedings pending the outcome of the Federal Circuit appeal of the ITC determination. On November 19, 2007, the Federal Circuit affirmed the ITC's findings in all respects, and SG did not file a petition for review. The parties subsequently filed a motion to dismiss the District Court case without prejudice. On November 4, 2009, the Company re-filed its complaint for patent infringement against SG and its parent corporations, Fairchild Semiconductor International, Inc. and Fairchild Semiconductor Corporation, to address their continued infringement of patents at issue in the original suit that recently emerged from SG requested reexamination proceedings before the U.S. Patent and Trademark Office (USPTO). The Company seeks, among other things, an order enjoining Fairchild and SG from infringing the Company's patents and an award of damages resulting from the alleged infringement. Fairchild has denied infringement and asked for a declaration from the Court that it does not infringe any Power Integrations patent, that the patents are invalid, and that one of the two of the Company's patents now at issue in the case is unenforceable. On May 5, 2010, Fairchild and SG filed an amended answer including counterclaims accusing the Company of infringing two patents, and since that time Fairchild has withdrawn its claim for infringement of one of the patents it originally asserted against the Company but added another patent to the case over the Company's objections; the Company contests these claims vigorously. Both parties filed summary judgment motions and challenges to each other’s experts’ testimony, and the Court granted the Company’s motion for summary judgment of non-infringement with respect to one of Fairchild’s two patents. Following a trial on the remaining claims in February 2014, the jury returned a verdict in the Company’s favor, affirming the validity of the asserted claims of the Company’s patents-in-suit, finding that Fairchild and SG willfully infringed the Company’s asserted patents and induced infringement by others, and awarding $105 million in damages. Although the jury awarded damages, at this stage of the proceedings the Company cannot state the amount, if any, it might ultimately recover from Fairchild, and no benefits have been recorded in the Company’s condensed consolidated financial statements as a result of the damages verdict. The Jury also rejected Fairchild’s remaining counterclaims for infringement against the Company. Fairchild has indicated that it intends to challenge these rulings and press its unenforceability claim with respect to one of the two patents it was found to infringe, while the Company intends to seek enhanced damages and injunctive relief; these issues are to be briefed in the coming months prior to a hearing scheduled for July 2014.
	In February 2010, Fairchild and System General (“SG”) filed suits for patent infringement against the Company, Power Integrations Netherlands B.V., and representative offices of Power Integrations Netherlands in Shanghai and Shenzhen with the Suzhou Intermediate Court in the People's Republic of China. The suits assert four Chinese patents and seek an injunction and damages of approximately $19.0 million. Power Integrations Netherlands filed invalidation proceedings for all four asserted SG patents in the People's Republic of China Patent Reexamination Board (PRB) of the State Intellectual Property Office (SIPO), and all four challenges were accepted by the PRB, with hearings conducted in September 2010. In early January 2012, the Company received rulings from the PRB invalidating the majority of the claims Fairchild asserted in litigation, and the PRB determinations are currently on appeal. The Suzhou Court conducted evidentiary hearings in 2012 and issued rulings in late December 2012, finding that the Company did not infringe any of the asserted patents. Fairchild has filed appeals challenging the Suzhou Court's non-infringement rulings, but the Company continues to believe the Fairchild and SG claims are without merit and will continue to contest them vigorously.
	On July 11, 2011, the Company filed a complaint in the U.S. District Court, District of Columbia, against David Kappos in his capacity as Director of the United States Patent and Trademark Office (“PTO”) as part of the ongoing reexamination proceedings related to one of the patents asserted against Fairchild and SG in the Delaware litigation described above. The Company filed a motion for summary judgment on a preliminary jurisdictional issue, and the PTO filed a cross-motion to dismiss on this same issue; briefing on those motions was completed in October, 2011. On November 18, 2013, the Court granted the PTO’s motion and transferred the case to the Federal Circuit, where additional briefing is expected to take place over the next few months.
	On May 1, 2012, Fairchild Semiconductor Corporation and Fairchild's wholly-owned subsidiary, System General Corporation (referred to collectively as “Fairchild”), filed a complaint against the Company in the United States District Court for the District of Delaware. In its complaint, Fairchild alleges that the Company has infringed and is infringing four patents pertaining to power conversion integrated circuit devices. The Company has answered Fairchild's complaint, denying infringement and asking for a declaration from the Court that it does not infringe any Fairchild patent and that the Fairchild patents are invalid, and the Company has also asserted counterclaims against Fairchild for infringement of five of the Company's patents. Fairchild has withdrawn its claim for infringement of one of the patents it asserted against the Company after the Company's preliminary challenge; discovery is under way on the remaining patents, with an anticipated trial date in 2015.
	On February 5, 2013, Trinity Capital Investment, LLC (“Trinity”) filed suit against the Company in California Superior Court.  The complaint alleged that SemiSouth Laboratories Inc. had entered into a lease agreement with Trinity, and that the Company guaranteed SemiSouth's obligations under the lease agreement.  The complaint further alleged that SemiSouth defaulted on the lease agreement in October 2012, and therefore the Company owed Trinity $2.4 million under the lease guaranty. On April 19, 2013, the Company answered the complaint, denying the allegations therein. On April 18, 2014, Trinity filed a request to dismiss the action without prejudice.
	The Company is unable to predict the outcome of legal proceedings with certainty, and there can be no assurance that Power Integrations will prevail in the above-mentioned unsettled litigations. These litigations, whether or not determined in Power Integrations' favor or settled, will be costly and will divert the efforts and attention of the Company's management and technical personnel from normal business operations, potentially causing a material adverse effect on the business, financial condition and operating results. Currently, the Company is not able to estimate a loss or a range of loss for the ongoing litigation disclosed above, however adverse determinations in litigation could result in monetary losses, the loss of proprietary rights, subject the Company to significant liabilities, require Power Integrations to seek licenses from third parties or prevent the Company from licensing the technology, any of which could have a material adverse effect on the Company's business, financial condition and operating results.
	Although the Company files U.S. federal, U.S. state, and foreign tax returns, its major tax jurisdiction is the U.S. In the quarter ended March 31, 2011, the IRS began an audit of fiscal years 2007 through 2009 which is currently in process. Audit outcomes and the timing of audit settlements are subject to significant uncertainty. It is reasonably possible that within the next 12 months the Company will resolve the matters presently under consideration for the 2007-2009 tax years with the IRS.

RECENT_ACCOUNTING_PRONOUNCEMEN

RECENT ACCOUNTING PRONOUNCEMENTS	3 Months Ended
	Mar. 31, 2014
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]	'
RECENT ACCOUNTING PRONOUNCEMENTS	'
	RECENT ACCOUNTING PRONOUNCEMENTS:
	Recently Adopted Standard
	In July 2013, the FASB issued a new accounting standard that requires the presentation of certain unrecognized tax benefits as reductions to deferred tax assets rather than as liabilities in the Company's Condensed Consolidated Balance Sheets when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists. The Company adopted this new standard on a prospective basis in the first quarter of 2014. The impact of the adoption was a reduction to long-term deferred tax assets and non current income tax payable of approximately $4.3 million.

BANK_LINE_OF_CREDIT

BANK LINE OF CREDIT	3 Months Ended
	Mar. 31, 2014
Debt Disclosure [Abstract]	'
BANK LINE OF CREDIT [Text Block]	'
	BANK LINE OF CREDIT:
	On July 5, 2012, the Company entered into a Credit Agreement (the "Credit Agreement") with two banks. The Credit Agreement provides the Company with a $100.0 million revolving line of credit to use for general corporate purposes with a $20.0 million sublimit for the issuance of standby and trade letters of credit. The Credit Agreement was amended on April 1, 2014, to extend the Credit Agreement termination date from July 5, 2015 to April 1, 2017, with all other terms of the Credit Agreement remaining the same. The Company's ability to borrow under the revolving line of credit is conditioned upon the Company's compliance with specified covenants, including reporting and financial covenants, primarily a minimum cash requirement and a debt to earnings ratio, with which the Company is currently in compliance. All advances under the revolving line of credit will become due on April 1, 2017, or earlier in the event of a default. As of March 31, 2014, the Company had no amount outstanding under the credit agreement.

SUMMARY_OF_SIGNIFICANT_ACCOUNT1

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Cash and Cash Equivalents [Policy Text Block]	'
	Cash and Cash Equivalents
	The Company considers cash invested in highly liquid financial instruments with maturities of three months or less at the date of purchase to be cash equivalents.
Marketable Securities [Policy Text Block]	'
	Marketable Securities
	The Company generally holds securities until maturity; however, they may be sold under certain circumstances including, but not limited to, when necessary for the funding of acquisitions and other strategic investments. As a result the Company classifies its investment portfolio as available-for-sale. The Company classifies all investments with an original maturity date greater than three months as short-term investments in its Condensed Consolidated Balance Sheet. As of March 31, 2014, and December 31, 2013, the Company's marketable securities consisted primarily of highly liquid corporate securities, commercial paper and other high-quality commercial securities.
Revenue Recognition [Policy Text Block]	'
	Revenue Recognition
	Product revenues consist of sales to original equipment manufacturers (“OEMs”), merchant power supply manufacturers and distributors. Approximately 75% of the Company's net product sales were made to distributors in the three months ended March 31, 2014, and 75% in the twelve months ended December 31, 2013. The Company applies the provisions of Accounting Standard Codification (“ASC”) 605-10 (“ASC 605-10”) and all related appropriate guidance. Revenue is recognized when all of the following criteria have been met: (1) persuasive evidence of an arrangement exists, (2) delivery has occurred, (3) the price is fixed or determinable, and (4) collectability is reasonably assured. Customer purchase orders are generally used to determine the existence of an arrangement. Delivery is considered to have occurred when title and risk of loss have transferred to the Company's customer. The Company evaluates whether the price is fixed or determinable based on the payment terms associated with the transaction and whether the sales price is subject to refund or adjustment. With respect to collectability, the Company performs credit checks for new customers and performs ongoing evaluations of its existing customers' financial condition and requires letters of credit whenever deemed necessary.
	Sales to international OEM customers and merchant power supply manufacturers that are shipped from the Company's facility in California are pursuant to “delivered at frontier” (“DAF”) shipping terms. As such, title to the product passes to the customer when the shipment reaches the destination country and revenue is recognized upon the arrival of the product in that country. Sales to international OEMs and merchant power supply manufacturers for shipments from the Company's facility outside of the United States are pursuant to “EX Works” ("EXW") shipping terms, meaning that title to the product transfers to the customer upon shipment from the Company's foreign warehouse. Shipments to OEMs and merchant power supply manufacturers in the Americas are pursuant to “free on board” (“FOB”) point of origin shipping terms meaning that title is passed to the customer upon shipment. Revenue is recognized upon title transfer for sales to OEMs and merchant power supply manufacturers, assuming all other criteria for revenue recognition are met.
	Sales to most of the Company's distributors are made under terms allowing certain price adjustments and rights of return on the Company's products held by its distributors. As a result of these rights, the Company defers the recognition of revenue and the costs of revenues derived from sales to distributors until the Company's distributors report that they have sold the Company's products to their customers. The Company's recognition of such distributor revenue is based on point of sale reports received from the distributors, at which time the price is no longer subject to adjustment and is fixed, and the products are no longer subject to return to the Company except pursuant to warranty terms. The gross profit that is deferred as a result of this policy is reflected as “deferred income on sales to distributors” in the accompanying condensed consolidated balance sheets. The total deferred revenue as of March 31, 2014, and December 31, 2013, was approximately $29.2 million and $25.5 million, respectively. The total deferred cost as of March 31, 2014, and December 31, 2013, was approximately $11.3 million and $9.8 million, respectively.
	Frequently, distributors need to sell at a price lower than the standard distribution price in order to win business. At or soon after the distributor invoices its customer, the distributor submits a “ship and debit” price adjustment claim to the Company to adjust the distributor's cost from the standard price to the pre-approved lower price. After verification by the Company, a credit memo is issued to the distributor for the ship and debit claim. The Company maintains a reserve for unprocessed claims and future ship and debit price adjustments. The reserve appears as a reduction to accounts receivable in the Company's accompanying consolidated balance sheets. To the extent future ship and debit claims significantly exceed amounts estimated, there could be a material impact on the deferred revenue and deferred margin ultimately recognized. To evaluate the adequacy of its reserves, the Company analyzes historical ship and debit payments and levels of inventory in the distributor channels.
	Sales to certain distributors of the Company are made under terms that do not include rights of return or price concessions after the product is shipped to the distributor. Accordingly, product revenue is recognized upon shipment and title transfer assuming all other revenue recognition criteria are met.
Use of Estimates [Policy Text Block]	'
	Use of Estimates
	The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. On an ongoing basis, the Company evaluates its estimates, including those related to revenue recognition, income tax, stock-based compensation and inventories. These estimates are based on historical facts and various other assumptions that the Company believes to be reasonable at the time the estimates are made.
Stock-Based Compensation [Policy Text Block]	'
	Stock-Based Compensation
	The Company applies the provisions of ASC 718-10. Under the provisions of ASC 718-10, the Company recognizes the fair value of stock-based compensation in financial statements over the requisite service period of the individual grants, which generally equals a four-year vesting period. The Company uses estimates of volatility, expected term, risk-free interest rate, dividend yield and forfeitures in determining the fair value of these awards and the amount of compensation expense to recognize. The Company uses the straight-line method to amortize all stock awards granted over the requisite service period of the award, and uses historical data to estimate pre-vesting forfeitures, recognizing expense only for those awards that are expected to vest.
	Determining Fair Value of Stock Options
	The Company uses the Black-Scholes valuation model for valuing stock option grants using the following assumptions and estimates:
	Expected Volatility. The Company calculates expected volatility based on the historical price volatility of the Company's stock.
	Expected Term. The Company utilizes a model which uses historical exercise, cancellation and outstanding option data to calculate the expected term of stock option grants.
	Risk-Free Interest Rate. The Company bases the risk-free interest rate used in the Black-Scholes valuation model on the implied yield available on a U.S. Treasury note with a term approximately equal to the expected term of the underlying grants.
	Dividend Yield.  The dividend yield was calculated by dividing the annual dividend by the average closing price of the Company's common stock on a quarterly basis.
Fair Value Measurements [Policy Text Block]	'
	FAIR VALUE MEASUREMENTS:
	ASC 820-10, Fair Value Measurements, clarifies that fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, ASC 820-10 establishes a three-tier value hierarchy, which prioritizes the inputs used in measuring fair value as follows: (Level 1) observable inputs such as quoted prices for identical assets in active markets; (Level 2) inputs other than the quoted prices in active markets that are observable either directly or indirectly; and (Level 3) unobservable inputs in which there is little or no market data, which requires the Company to develop its own assumptions. This hierarchy requires the Company to use observable market data, when available, and to minimize the use of unobservable inputs when determining fair value.
	The Company's cash and investment instruments are classified within Level 1 or Level 2 of the fair-value hierarchy because they are valued using quoted market prices, broker or dealer quotations, or alternative pricing sources with reasonable levels of price transparency. The type of instrument valued based on quoted market prices in active markets primarily includes money market securities. This type of instrument is generally classified within Level 1 of the fair-value hierarchy. The types of instruments valued based on other observable inputs (Level 2 of the fair-value hierarchy) include investment-grade corporate bonds and government, state, municipal and provincial obligations. Such types of investments are valued by using a multi-dimensional relational model, the inputs are primarily benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, and reference data including market research publications. The Company principally holds securities until maturity; however, they may be sold under certain circumstances, including, but not limited to, the funding of acquisitions and other strategic investments. As a result the Company classified its investment portfolio as available-for-sale. The Company's investments classified as Level 1 and Level 2 are available-for-sale investments, and were recorded at fair market value.
Segment Reporting [Policy Text Block]	'
	Segment Reporting
	The Company is organized and operates as one reportable segment, the design, development, manufacture and marketing of integrated circuits and related components for use primarily in the high-voltage power-conversion market. The Company's chief operating decision maker, the Chief Executive Officer, reviews financial information presented on a consolidated basis for purposes of making operating decisions and assessing financial performance.
Earnings Per Share [Policy Text Block]	'
	EARNINGS PER SHARE:
	Basic earnings per share are calculated by dividing net income by the weighted-average shares of common stock outstanding during the period. Diluted earnings per share are calculated by dividing net income by the weighted-average shares of common stock and dilutive common equivalent shares outstanding during the period. Dilutive common equivalent shares included in this calculation consist of dilutive shares issuable upon the assumed exercise of outstanding common stock options, the assumed vesting of outstanding restricted stock units and both short- and long-term performance-based awards, and the assumed issuance of awards under the stock purchase plan, as computed using the treasury stock method.

SUMMARY_OF_SIGNIFICANT_ACCOUNT2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Available-for-sale Securities [Table Text Block]	'
	Amortized cost and estimated fair market value of investments classified as available-for-sale at March 31, 2014, are as follows (in thousands):
		Amortized			Gross Unrealized							Estimated Fair
		Cost			Gains			Losses				Market Value
	Investments due in less than 3 months:
	Commercial paper	$	3,722		$	1		$	—			$	3,723
	Total	$	3,722		$	1		$	—			$	3,723
	Investments due in 4-12 months:
	Corporate securities	$	16,502		$	63		$	—			$	16,565
	Total	$	16,502		$	63		$	—			$	16,565
	Investments due between 12 months and 5-years:
	Corporate securities	$	116,826		$	300		$	(7	)		$	117,119
	Total	$	116,826		$	300		$	(7	)		$	117,119
	Total investment securities	$	137,050		$	364		$	(7	)		$	137,407
	Amortized cost and estimated fair market value of investments classified as available-for-sale at December 31, 2013, are as follows (in thousands):
		Amortized			Gross Unrealized							Estimated Fair
		Cost			Gains			Losses				Market Value
	Investments due in less than 3 months:
	Commercial paper	$	3,098		$	1		$	—			$	3,099
	Total	$	3,098		$	1		$	—			$	3,099
	Investments due in 4-12 months:
	Corporate securities	$	6,007		$	33		$	—			$	6,040
	Total	$	6,007		$	33		$	—			$	6,040
	Investments due between 12 months and 5-years:
	Corporate securities	$	102,963		$	202		$	(26	)		$	103,139
	Total	$	102,963		$	202		$	(26	)		$	103,139
	Total investment securities	$	112,068		$	236		$	(26	)		$	112,278
Schedule of Accounts Receivable [Table Text Block]	'
	Accounts Receivable (in thousands):
		March 31,			December 31,
		2014			2013
	Accounts receivable trade	$	47,842		$	42,410
	Accrued ship and debit and rebate claims	(31,316		)	(29,901		)
	Allowance for doubtful accounts	(105		)	(120		)
	Total	$	16,421		$	12,389
Schedule of Prepaid Expenses and Other Current Assets [Table Text Block]	'
	Prepaid Expenses and Other Current Assets (in thousands):
		March 31,			December 31,
		2014			2013
	Prepaid legal fees	$	5,129		$	6,267
	Prepaid income tax	4,048			7,521
	Prepaid maintenance agreements	725			947
	Interest receivable	678			519
	Supplier prepayment	1,511			757
	Other	4,936			2,621
	Total	$	17,027		$	18,632
Changes in Accumulated Other Comprehensive Income (Loss) [Table Text Block]	'
	Changes in accumulated other comprehensive income (loss) for the quarter ended March 31, 2013 (in thousands):
		Unrealized Gains and Losses on Available-for-Sale Securities			Defined Benefit Pension Items				Foreign Currency Items				Total
	Beginning balance at December 31, 2012	$	138		$	(560	)		$	129			$	(293	)
	Other comprehensive income before reclassifications	(54		)	—				(151		)		(205		)
	Amounts reclassified from accumulated other comprehensive income	—			14			-1	—				14
	Net-current period other comprehensive income	(54		)	14				(151		)		(191		)
	Ending balance at March 31, 2013	$	84		$	(546	)		$	(22	)		$	(484	)
	____________________________
	(1) This component of accumulated other comprehensive income is included in the computation of net periodic pension cost for the three months ended March 31, 2013.
	Changes in accumulated other comprehensive income (loss) for the three months ended March 31, 2014 (in thousands):
		Unrealized Gains and Losses on Available-for-Sale Securities			Defined Benefit Pension Items				Foreign Currency Items				Total
	Beginning balance at December 31, 2013	$	210		$	(780	)		$	100			$	(470	)
	Other comprehensive income (loss) before reclassifications	147			—				(6		)		141
	Amounts reclassified from accumulated other comprehensive income (loss)	—			14			-1	—				14
	Net-current period other comprehensive income (loss)	147			14				(6		)		155
	Ending balance at March 31, 2014	$	357		$	(766	)		$	94			$	(315	)
	____________________________
	(1) This component of accumulated other comprehensive income is included in the computation of net periodic pension cost for the three months ended March 31, 2014.

STOCK_PLANS_AND_SHAREBASED_COM1

STOCK PLANS AND SHARE-BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Stock-based Compensation Expense [Table Text Block]	'
	The following table summarizes the stock-based compensation expense recognized in accordance with ASC 718-10 for the three months ended March 31, 2014, and March 31, 2013 (in thousands).
		Three Months Ended
		March 31,
		2014				2013
	Cost of revenues	$	219			$	264
	Research and development	1,212				1,106
	Sales and marketing	935				829
	General and administrative	1,549				1,437
	Total stock-based compensation expense	$	3,915			$	3,636
Schedule of Unrecognized Compensation Expense for Unvested Awards [Table Text Block]	'
	The following table summarizes total compensation expense related to unvested awards not yet recognized, net of expected forfeitures, and the weighted-average period over which it is expected to be recognized as of March 31, 2014.
		March 31, 2014
		Unrecognized					Weighted Average
		Compensation					Remaining
		Expense for Unvested					Recognition
		Awards					Period
		(In thousands)					(In years)
	Options		$	1,497				1.44
	Performance-based awards		1,706					0.75
	Long term performance-based awards		2,156					2.75
	Restricted stock units		20,511					2.38
	Purchase plan		396					0.5
	Total unrecognized compensation expense		$	26,266
Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]	'
	The fair value of employees’ stock purchase rights under the Purchase Plan was estimated using the Black-Scholes model with the following weighted-average assumptions:
		Three Months Ended
		March 31,
		2014		2013
	Risk-free interest rates	0.07%		0.11%
	Expected volatility rates	30%		33%
	Expected dividend yield	0.66%		0.80%
	Expected term of purchase right (in years)	0.5		0.5
	Weighted-average estimated fair value of purchase rights	$13.31		$9.14
Summary of Option Activity Under the Plans	'
	A summary of stock option activity under the Plans, excluding performance-based awards and restricted stock units, as of March 31, 2014, and changes during the three months then ended is presented below:
		Shares			Weighted-			Weighted-Average		Aggregate
		(in thousands)			Average			Remaining		Intrinsic Value
					Exercise			Contractual		(in thousands)
					Price			Term
								(in years)
	Outstanding at January 1, 2014	1,691			$27.34
	Granted	—			—
	Exercised	(176	)		$27.26
	Forfeited or expired	—			—
	Outstanding at March 31, 2014	1,515			$27.35			4.3		$	58,210
	Exercisable at March 31, 2014	1,400			$26.29			4.03		$	55,288
	Vested and expected to vest at March 31, 2014	1,512			$27.32			4.29		$	58,145
Performance Based Awards [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]	'
	A summary of performance-based awards outstanding as of March 31, 2014, and activity during the three months then ended, is presented below:
		Shares			Weighted- Average Grant Date Fair Value Per Share			Weighted-Average Remaining Contractual Term		Aggregate Intrinsic Value
		(in thousands)						(in years)		(in thousands)
	Outstanding at January 1, 2014	100			$38.48
	Granted	44			$58.55
	Vested	(83	)		$38.48
	Change in units due to performance achievement for PSUs vested in the year	(17	)		$38.48
	Forfeited or expired	—			—
	Outstanding at March 31, 2014	44			$58.55			0.75		$	2,868
	Outstanding and expected to vest at March 31, 2014	37						0.75		$	2,466
Long-Term Performance-based Awards [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]	'
	A summary of long-term performance-based awards outstanding as of March 31, 2014, and activity during the three months then ended, is presented below:
		Shares			Weighted- Average Grant Date Fair Value Per Share			Weighted-Average Remaining Contractual Term		Aggregate Intrinsic Value
		(in thousands)						(in years)		(in thousands)
	Outstanding at January 1, 2014	—			—
	Granted	47			$57.76
	Vested	—			—
	Forfeited or expired	—			—
	Outstanding at March 31, 2014	47			$57.76			2.75		$	3,072
	Outstanding and expected to vest at March 31, 2014	40						2.75		$	2,629
Restricted Stock Units (RSUs) [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]	'
	A summary of RSUs outstanding as of March 31, 2014, and changes during the three months then ended, are as follows:
		Shares			Weighted- Average Grant Date Fair Value Per Share		Weighted-Average Remaining Contractual Term		Aggregate Intrinsic Value
		(in thousands)					(in years)		(in thousands)
	Outstanding at January 1, 2014	714			$38.97
	Granted	86			$57.05
	Vested	(46	)		$35.93
	Forfeited or expired	(4	)		$39.47
	Outstanding at March 31, 2014	750			$41.21		1.44		$	49,312
	Outstanding and expected to vest at March 31, 2014	704					1.34		$	46,280

FAIR_VALUE_MEASUREMENTS_Tables

FAIR VALUE MEASUREMENTS (Tables)	3 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
Fair value of marketable securities and investments [Table Text Block]	'
	The fair-value hierarchy of the Company's marketable securities at March 31, 2014, and December 31, 2013, was as follows (in thousands):
		Fair Value Measurement at
		March 31, 2014
	Description	March 31, 2014		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)
	Commercial paper	$	3,723	$	—	$	3,723
	Money market funds	17,516		17,516		—
	Corporate securities	133,684		—		133,684
	Total	$	154,923	$	17,516	$	137,407
		Fair Value Measurement at
		December 31, 2013
	Description	December 31, 2013		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)
	Commercial paper	$	3,099	$	—	$	3,099
	Money market funds	17,492		17,492		—
	Corporate securities	109,179		—		109,179
	Total	$	129,770	$	17,492	$	112,278

INVENTORIES_Tables

INVENTORIES (Tables)	3 Months Ended
	Mar. 31, 2014
Inventory Disclosure [Abstract]	'
Inventories [Table Text Block]	'
	Inventories consist of the following (in thousands):
		March 31,		December 31,
		2014		2013
	Raw materials	$	11,257	$	8,221
	Work-in-process	12,207		13,216
	Finished goods	24,470		20,798
	Total	$	47,934	$	42,235

GOODWILL_AND_INTANGIBLE_ASSETS1

GOODWILL AND INTANGIBLE ASSETS (Tables)	3 Months Ended
	Mar. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Schedule of intangible assets [Table Text Block]	'
	The Company does not believe there is any significant residual value associated with the following intangible assets:
		March 31, 2014								December 31, 2013
		Gross			Accumulated			Net		Gross		Accumulated			Net
					Amortization							Amortization
		(in thousands)
	In-process research and development	$	4,690		$	—		$	4,690	$	4,690	$	—		$	4,690
	Technology licenses	3,000			(2,400		)	600		3,000		(2,325		)	675
	Patent rights	1,949			(1,949		)	—		1,949		(1,949		)	—
	Developed technology	26,670			(5,893		)	20,777		26,670		(5,247		)	21,423
	Customer relationships	17,610			(5,349		)	12,261		17,610		(4,664		)	12,946
	Trade name	3,600			(3,450		)	150		3,600		(3,000		)	600
	Total intangible assets	$	57,519		$	(19,041	)	$	38,478	$	57,519	$	(17,185	)	$	40,334
Schedule of expected amortization expense [Table Text Block]	'
	The estimated future amortization expense related to intangible assets at March 31, 2014, is as follows:
	Fiscal Year		Estimated
			Amortization
			(in  thousands)
	2014	(remaining 9 months)	$	4,216
	2015		5,009
	2016		4,394
	2017		3,994
	2018		3,746
	Thereafter		12,429
	Total (1)		$	33,788
	_______________
	-1	The total above excludes $4.7 million of in-process research and development that will be amortized upon completion of development over the estimated useful life of the technology.

SIGNIFICANT_CUSTOMERS_AND_EXPO1

SIGNIFICANT CUSTOMERS AND EXPORT SALES (Tables)	3 Months Ended
	Mar. 31, 2014
Concentration Risk [Line Items]	'
International sales [Table Text Block]	'
	As a percentage of total net revenues, international sales, which consist of domestic and foreign sales to distributors and direct customers outside of the United States of America, comprise the following:
		Three Months  Ended
		March 31,
		2014		2013
	Hong Kong/China	44	%	44	%
	Taiwan	16	%	15	%
	Korea	11	%	13	%
	Western Europe (excluding Germany)	11	%	12	%
	Japan	6	%	5	%
	Singapore	2	%	3	%
	Germany	2	%	2	%
	Other	3	%	1	%
	Total foreign revenue	95	%	95	%
Revenue mix by product family [Table Text Block]	'
	the three months ended March 31, 2014 and 2013:
		Three Months Ended
		March 31,
	End Market	2014		2013
	Communications	18	%	22	%
	Computer	10	%	10	%
	Consumer	37	%	36	%
	Industrial	35	%	32	%
Sales Revenue, Goods, Net [Member]	'
Concentration Risk [Line Items]	'
Schedules of Concentration of Risk, by Risk Factor [Table Text Block]	'
	Customers representing 10% or more of total net revenues are as follows:
		Three Months Ended
		March 31,
	Customer	2014		2013
	A	19	%	19	%
	B	*		10	%
	____________________
	* Total customer revenue was less than 10% of net revenues.
Accounts Receivable [Member]	'
Concentration Risk [Line Items]	'
Schedules of Concentration of Risk, by Risk Factor [Table Text Block]	'
	The following customers represented 10% or more of accounts receivable:
	Customer	March 31,		December 31,
		2014		2013
	Avnet	27	%	21	%
	ATM Electronic Corporation	11	%	17	%

EARNINGS_PER_SHARE_Tables

EARNINGS PER SHARE (Tables)	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Abstract]	'
Earnings per share calculation [Table Text Block]	'
	A summary of the earnings per share calculation is as follows (in thousands, except per share amounts):
		Three Months Ended
		March 31,
		2014		2013
	Basic earnings per share:
	Net income	$	12,363	$	10,903
	Weighted-average common shares	30,239		28,754
	Basic earnings per share	$	0.41	$	0.38
	Diluted earnings per share (1):
	Net income	$	12,363	$	10,903
	Weighted-average common shares	30,239		28,754
	Effect of dilutive securities:
	Employee stock plans	928		1,029
	Diluted weighted-average common shares	31,167		29,783
	Diluted earnings per share	$	0.4	$	0.37
	_______________
	-1	The Company includes the shares underlying performance-based awards in the calculation of diluted earnings per share if the performance conditions have been satisfied as of the end of the reporting period and excludes such shares when the necessary conditions have not been met. The Company has excluded the shares underlying the 2014 and 2013 awards in the 2014 and 2013 calculation, respectively, as those shares were not contingently issuable as of the end of the period.

SUMMARY_OF_SIGNIFICANT_ACCOUNT3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Available-for-sale Investments) (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized cost	$137,050	$112,068
Gross Unrealized Gains	364	236
Gross Unrealized Losses	-7	-26
Estimated Fair Market Value	137,407	112,278
Investments due in less than 3 months [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized cost	3,722	3,098
Gross Unrealized Gains	1	1
Gross Unrealized Losses	0	0
Estimated Fair Market Value	3,723	3,099
Investments due in 4-12 months [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized cost	16,502	6,007
Gross Unrealized Gains	63	33
Gross Unrealized Losses	0	0
Estimated Fair Market Value	16,565	6,040
Investments due in more than 12 months [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized cost	116,826	102,963
Gross Unrealized Gains	300	202
Gross Unrealized Losses	-7	-26
Estimated Fair Market Value	117,119	103,139
Commercial paper [Member] | Investments due in less than 3 months [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized cost	3,722	3,098
Gross Unrealized Gains	1	1
Gross Unrealized Losses	0	0
Estimated Fair Market Value	3,723	3,099
Corporate securities [Member] | Investments due in 4-12 months [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized cost	16,502	6,007
Gross Unrealized Gains	63	33
Gross Unrealized Losses	0	0
Estimated Fair Market Value	16,565	6,040
Corporate securities [Member] | Investments due in more than 12 months [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized cost	116,826	102,963
Gross Unrealized Gains	300	202
Gross Unrealized Losses	-7	-26
Estimated Fair Market Value	$117,119	$103,139

SUMMARY_OF_SIGNIFICANT_ACCOUNT4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $)	3 Months Ended				12 Months Ended
	Mar. 31, 2014		Mar. 31, 2013		Dec. 31, 2013
Deferred Revenue [Abstract]	'		'		'
Net product sales, percentage	75.00%		'		75.00%
Deferred revenue	$29,200,000		'		$25,500,000
Deferred cost	11,300,000		'		9,800,000
Accounts Receivable [Abstract]	'		'		'
Accounts receivable trade	47,842,000		'		42,410,000
Accrued ship and debit and rebate claims	-31,316,000		'		-29,901,000
Allowance for doubtful accounts	-105,000		'		-120,000
Total	16,421,000		'		12,389,000
Prepaid Expenses and Other Current Assets [Abstract]	'		'		'
Prepaid legal fees	5,129,000		'		6,267,000
Prepaid income tax	4,048,000		'		7,521,000
Prepaid maintenance agreements	725,000		'		947,000
Interest receivable	678,000		'		519,000
Supplier Prepayment	1,511,000		'		757,000
Other	4,936,000		'		2,621,000
Total	17,027,000		'		18,632,000
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'
Beginning balance	-470,000		-293,000		-293,000
Other comprehensive income (loss) before reclassifications	141,000		-205,000		'
Amounts reclassified from accumulated other comprehensive income	14,000		14,000		'
Total other comprehensive income (loss)	155,000		-191,000		'
Ending balance	-315,000		-484,000		-470,000
Unrealized Gains and Losses on Available-for-Sale Securities [Member]	'		'		'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'
Beginning balance	210,000		138,000		138,000
Other comprehensive income (loss) before reclassifications	147,000		-54,000		'
Amounts reclassified from accumulated other comprehensive income	0		0		'
Total other comprehensive income (loss)	147,000		-54,000		'
Ending balance	357,000		84,000		'
Defined Benefit Pension Items [Member]	'		'		'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'
Beginning balance	-780,000		-560,000		-560,000
Other comprehensive income (loss) before reclassifications	0		0		'
Amounts reclassified from accumulated other comprehensive income	14,000	[1]	14,000	[2]	'
Total other comprehensive income (loss)	14,000		14,000		'
Ending balance	-766,000		-546,000		'
Foreign Currency Items [Member]	'		'		'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'
Beginning balance	100,000		129,000		129,000
Other comprehensive income (loss) before reclassifications	-6,000		-151,000		'
Amounts reclassified from accumulated other comprehensive income	0		0		'
Total other comprehensive income (loss)	-6,000		-151,000		'
Ending balance	$94,000		($22,000)		'
[1]	This component of accumulated other comprehensive income is included in the computation of net periodic pension cost for the three months ended March 31, 2014.
[2]	This component of accumulated other comprehensive income is included in the computation of net periodic pension cost for the three months ended March 31, 2013.

SUMMARY_OF_SIGNIFICANT_ACCOUNT5

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Common Stock Repurchases and Common Stock Dividend) (Details) (USD $)	1 Months Ended			3 Months Ended					1 Months Ended
	Oct. 31, 2013	Jan. 31, 2013	Jan. 31, 2012	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Oct. 31, 2012	Apr. 30, 2014
		quarters	quarters						Common Stock [Member]	Subsequent Event [Member]
Class of Stock [Line Items]	'	'	'	'	'	'	'	'	'	'
Stock repurchase program authorized amount	'	'	'	'	'	'	'	'	$50,000,000	'
Remaining authorized repurchase amount	'	'	'	29,500,000	'	'	'	'	'	'
Dividends declared (per share)	$0.10	$0.08	'	'	'	'	'	'	'	$0.12
Number of shares repurchased	'	'	'	0	'	'	'	'	'	'
Dividends declared, number of quarters	'	4	4	'	'	'	'	'	'	'
Payments of dividends (per share)	'	'	'	$0.10	$0.08	$0.08	$0.08	$0.08	'	'
Common stock dividends declared for second quarter of fiscal year 2014 (per share)	'	'	'	$0.10	'	'	'	'	'	'
Common stock dividends declared for third quarter of fiscal year 2014 (per share)	'	'	'	$0.12	'	'	'	'	'	'
Common stock dividends declared for fourth quarter of fiscal year 2014 (per share)	'	'	'	$0.12	'	'	'	'	'	'
Payments of dividends	'	'	'	$3,033,000	$2,400,000	$2,400,000	$2,300,000	$2,310,000	'	'

STOCK_PLANS_AND_SHAREBASED_COM2

STOCK PLANS AND SHARE-BASED COMPENSATION (Details) (USD $)

3 Months Ended

3 Months Ended

1 Months Ended

3 Months Ended

3 Months Ended

1 Months Ended

3 Months Ended

1 Months Ended

3 Months Ended

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Dec. 31, 2013

Jul. 31, 2012

Mar. 31, 2014

Mar. 31, 2013

Dec. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Jul. 31, 2012

Mar. 31, 2014

Jul. 31, 2012

Mar. 31, 2014

plans

2007 Equity Incentive Plan [Member]

Directors Equity Compensation Program [Member]

Maximum [Member]

Employee Stock [Member]

Employee Stock [Member]

Restricted Stock Units (RSUs) [Member]

Restricted Stock Units (RSUs) [Member]

Restricted Stock Units (RSUs) [Member]

Restricted Stock Units (RSUs) [Member]

Performance Based Awards [Member]

Performance Based Awards [Member]

Performance Based Awards [Member]

Stock Options [Member]

Stock Options [Member]

Stock Options [Member]

Incentive Stock Options [Member]

Stock Options and Restricted Stock Units (RSUs) [Member]

Nonstatutory Stock Options [Member]

purchaseperiods

Directors Equity Compensation Program [Member]

Directors Equity Compensation Program [Member]

2007 Equity Incentive Plan [Member]

Directors Equity Compensation Program [Member]

2007 Equity Incentive Plan [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of shares available for future issuance

'

'

'

'

6,870,264

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Exercise price of stock options as percentage of fair market value on date of grant, minimum

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

100.00%

'

100.00%

Vesting period

'

'

'48 months

'3 years

'

'

'

'4 years

'

'

'

'

'

'

'4 years

'

'

'

'

'

Factor used to determine the number of options/units to be granted

'

'

'

'

'

'

'

'

'

'

$100,000

'

'

'

'

'

$100,000

'

$100,000

'

Maximum percentage of employee's compensation eligible for payroll deductions

'

'

'

'

'

15.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Purchase price of the purchase plan as percentage of the lower of the fair market value on the first day of each offering period or on the purchase date

'

'

'

'

'

85.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shares reserved for issuance

'

'

'

'

'

3,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Employee Shares Purchased for Award

'

'

'

'

'

2,646,861

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant

'

'

'

'

'

353,139

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Allocated Share-based Compensation Expense

$3,915,000

$3,636,000

'

'

'

$300,000

$300,000

$2,600,000

$1,900,000

'

'

$500,000

$400,000

'

$500,000

$1,000,000

'

'

'

'

Number of stock-based compensation plans

2

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Awards expiration period, maximum (in years)

'

'

'10 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of purchase period in each offering period

'

'

'

'

'

1

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Duration of each purchase period in each offering period

'

'

'

'

'

'6 months

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of performance-based awards shares released as percentage of target number, minimum

'

'

'

'

'

'

'

'

'

'

'

0.00%

'

'

'

'

'

'

'

'

Number of performance-based awards shares released as percentage of target number, maximum

'

'

'

'

'

'

'

'

'

'

'

200.00%

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period

'

'

'

'

'

'

'

46,000

'

'

'

83,000

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

'

'

'

'

'

'

'

750,000

'

714,000

'

44,000

'

100,000

'

'

'

'

'

'

STOCK_PLANS_AND_SHAREBASED_COM3

STOCK PLANS AND SHARE-BASED COMPENSATION (Stock-Based Compensation) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Stock-based compensation expense for stock options, stock awards and employee stock purchases included in operations:	'	'
Stock-based compensation expense	$3,915	$3,636
Unrecognized Compensation Expense for Unvested Awards	26,266	'
Cost of revenues [Member]	'	'
Stock-based compensation expense for stock options, stock awards and employee stock purchases included in operations:	'	'
Stock-based compensation expense	219	264
Research and development [Member]	'	'
Stock-based compensation expense for stock options, stock awards and employee stock purchases included in operations:	'	'
Stock-based compensation expense	1,212	1,106
Sales and marketing [Member]	'	'
Stock-based compensation expense for stock options, stock awards and employee stock purchases included in operations:	'	'
Stock-based compensation expense	935	829
General and administrative [Member]	'	'
Stock-based compensation expense for stock options, stock awards and employee stock purchases included in operations:	'	'
Stock-based compensation expense	1,549	1,437
Employee Stock Option [Member]	'	'
Stock-based compensation expense for stock options, stock awards and employee stock purchases included in operations:	'	'
Stock-based compensation expense	500	1,000
Unrecognized Compensation Expense for Unvested Awards	1,497	'
Weighted Average Remaining Recognition Period (in years)	'1 year 5 months 8 days	'
Performance Based Awards [Member]	'	'
Stock-based compensation expense for stock options, stock awards and employee stock purchases included in operations:	'	'
Stock-based compensation expense	500	400
Unrecognized Compensation Expense for Unvested Awards	1,706	'
Weighted Average Remaining Recognition Period (in years)	'9 months	'
Long-Term Performance-based Awards [Member]	'	'
Stock-based compensation expense for stock options, stock awards and employee stock purchases included in operations:	'	'
Unrecognized Compensation Expense for Unvested Awards	2,156	'
Weighted Average Remaining Recognition Period (in years)	'2 years 9 months	'
Restricted Stock Units (RSUs) [Member]	'	'
Stock-based compensation expense for stock options, stock awards and employee stock purchases included in operations:	'	'
Stock-based compensation expense	2,600	1,900
Unrecognized Compensation Expense for Unvested Awards	20,511	'
Weighted Average Remaining Recognition Period (in years)	'2 years 4 months 17 days	'
Employee Stock [Member]	'	'
Stock-based compensation expense for stock options, stock awards and employee stock purchases included in operations:	'	'
Stock-based compensation expense	300	300
Unrecognized Compensation Expense for Unvested Awards	$396	'
Weighted Average Remaining Recognition Period (in years)	'6 months	'

STOCK_PLANS_AND_SHAREBASED_COM4

STOCK PLANS AND SHARE-BASED COMPENSATION (Fair Value Assumptions) (Details) (Employee Stock [Member], USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Employee Stock [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Risk-free interest rates	0.07%	0.11%
Expected volatility rates	30.00%	33.00%
Expected dividend yield	0.66%	0.80%
Expected term of stock options/purchase right (in years)	'6 months	'6 months
Weighted-average estimated fair value of purchase rights	$13.31	$9.14

STOCK_PLANS_AND_SHAREBASED_COM5

STOCK PLANS AND SHARE-BASED COMPENSATION (Option Activity) (Details) (Stock Options [Member], USD $)	3 Months Ended
Share data in Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Stock Options [Member]	'	'
Option activity under the Plans	'	'
Outstanding, shares, at January 1, 2014	1,691	'
Granted, shares	0	'
Exercised, shares	-176	'
Forfeited or expired, shares	0	'
Outstanding, shares, at March 31, 2014	1,515	'
Exercisable, shares, at March 31, 2014	1,400	'
Vested and expected to vest, shares, at March 31, 2014	1,512	'
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]	'	'
Outstanding, weighted-average exercise price, at January 1, 2014	$27.34	'
Granted, weighted-average exercise price	$0	'
Exercised, weighted-average exercise price	$27.26	'
Forfeited or expired, weighted-average exercise price	$0	'
Outstanding, weighted-average exercise price, at March 31, 2014	$27.35	'
Exercisable, weighted-average exercise price, at March 31, 2014	$26.29	'
Vested and expected to vest, weighted-average exercise price, at March 31, 2014	$27.32	'
Weighted Average Remaining Contractual Term [Abstract]	'	'
Outstanding, weighted-average remaining contractual term at March 31, 2014 (in years)	'4 years 3 months 18 days	'
Exercisable, weighted-average remaining contractual term, at March 31, 2014 (in years)	'4 years 0 months 10 days	'
Vested and expected to vest, weighted-average remaining contractual term, at March 31, 2014 (in years)	'4 years 3 months 14 days	'
Aggregate Intrinsic Value [Abstract]	'	'
Outstanding, aggregate intrinsic value at March 31, 2014	$58,210,000	'
Exercisable, aggregate intrinsic value, at March 31, 2014	55,288,000	'
Vested and expected to vest, aggregate intrinsic value, at March 31, 2014	58,145,000	'
Intrinsic Value of Options Excercised	$5,800,000	$5,200,000

STOCK_PLANS_AND_SHAREBASED_COM6

STOCK PLANS AND SHARE-BASED COMPENSATION (Performance-based Awards and Restricted Stock Units) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Performance Based Awards [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Grant date fair value of awards released	$3,200,000	$2,000,000
Number of performance-based awards shares released as percentage of target number, minimum	0.00%	'
Number of performance-based awards shares released as percentage of target number, maximum	200.00%	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]	'	'
Outstanding, shares, at January 1, 2014	100,000	'
Granted, shares	44,000	'
Vested, shares	-83,000	'
Change in units due to performance achievement for PSUs vested in the year, shares	-17,000	'
Forfeited or expired, shares	0	'
Outstanding, shares, at March 31, 2014	44,000	'
Outstanding and expected to vest at March 31, 2014	37,000	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]	'	'
Outstanding, weighted-average grant date fair value per share, at January 1, 2014	$38.48	'
Granted, weighted-average grant date fair value per share	$58.55	$36.43
Vested, weighted-average grant date fair value per share	$38.48	'
Change in units due to performance achievement for PSUs vested in the year per share	$38.48	'
Forfeited or expired, weighted-average grant date fair value per share	$0	'
Outstanding, weighted-average grant date fair value per share, at March 31, 2014	$58.55	'
Weighted Average Remaining Contractual Term [Abstract]	'	'
Outstanding and expected to vest, weighted-average remaining contractual term, at March 31, 2014 (in years)	'9 months	'
Outstanding and expected to vest, weighted-average remaining contractual term, at March 31, 2014 (in years)	'9 months	'
Aggregate Intrinsic Value [Abstract]	'	'
Outstanding, aggregate intrinsic value, at March 31, 2014	2,868,000	'
Outstanding and expected to vest, aggregate intrinsic value, at March 31, 2014	2,466,000	'
Long-Term Performance-based Awards [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]	'	'
Outstanding, shares, at January 1, 2014	0	'
Granted, shares	47,000	'
Vested, shares	0	'
Forfeited or expired, shares	0	'
Outstanding, shares, at March 31, 2014	47,000	'
Outstanding and expected to vest at March 31, 2014	40,000	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]	'	'
Outstanding, weighted-average grant date fair value per share, at January 1, 2014	$0	'
Granted, weighted-average grant date fair value per share	$57.76	'
Vested, weighted-average grant date fair value per share	$0	'
Forfeited or expired, weighted-average grant date fair value per share	$0	'
Outstanding, weighted-average grant date fair value per share, at March 31, 2014	$57.76	'
Weighted Average Remaining Contractual Term [Abstract]	'	'
Outstanding and expected to vest, weighted-average remaining contractual term, at March 31, 2014 (in years)	'2 years 9 months	'
Outstanding and expected to vest, weighted-average remaining contractual term, at March 31, 2014 (in years)	'2 years 9 months	'
Aggregate Intrinsic Value [Abstract]	'	'
Outstanding, aggregate intrinsic value, at March 31, 2014	3,072,000	'
Outstanding and expected to vest, aggregate intrinsic value, at March 31, 2014	2,629,000	'
Restricted Stock Units (RSUs) [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Vesting period	'4 years	'
Grant date fair value of awards released	1,600,000	200,000
Reduction in number of shares available for issuance under the 2007 Plan per award granted	2	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]	'	'
Outstanding, shares, at January 1, 2014	714,000	'
Granted, shares	86,000	'
Vested, shares	-46,000	'
Forfeited or expired, shares	-4,000	'
Outstanding, shares, at March 31, 2014	750,000	'
Outstanding and expected to vest at March 31, 2014	704,000	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]	'	'
Outstanding, weighted-average grant date fair value per share, at January 1, 2014	$38.97	'
Granted, weighted-average grant date fair value per share	$57.05	$35.68
Vested, weighted-average grant date fair value per share	$35.93	'
Forfeited or expired, weighted-average grant date fair value per share	$39.47	'
Outstanding, weighted-average grant date fair value per share, at March 31, 2014	$41.21	'
Weighted Average Remaining Contractual Term [Abstract]	'	'
Outstanding and expected to vest, weighted-average remaining contractual term, at March 31, 2014 (in years)	'1 year 5 months 8 days	'
Outstanding and expected to vest, weighted-average remaining contractual term, at March 31, 2014 (in years)	'1 year 4 months 2 days	'
Aggregate Intrinsic Value [Abstract]	'	'
Outstanding, aggregate intrinsic value, at March 31, 2014	49,312,000	'
Outstanding and expected to vest, aggregate intrinsic value, at March 31, 2014	$46,280,000	'

FAIR_VALUE_MEASUREMENTS_Detail

FAIR VALUE MEASUREMENTS (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Estimate of Fair Value, Fair Value Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Disclosure	$154,923	$129,770
Estimate of Fair Value, Fair Value Disclosure [Member] | Money market funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and Cash Equivalents, Fair Value Disclosure	17,516	17,492
Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial paper [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and Cash Equivalents, Fair Value Disclosure	3,723	3,099
Estimate of Fair Value, Fair Value Disclosure [Member] | Corporate securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Investments, Fair Value Disclosure	133,684	109,179
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Disclosure	17,516	17,492
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Money market funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and Cash Equivalents, Fair Value Disclosure	17,516	17,492
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Commercial paper [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Corporate securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Investments, Fair Value Disclosure	0	0
Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Disclosure	137,407	112,278
Significant Other Observable Inputs (Level 2) [Member] | Money market funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Significant Other Observable Inputs (Level 2) [Member] | Commercial paper [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and Cash Equivalents, Fair Value Disclosure	3,723	3,099
Significant Other Observable Inputs (Level 2) [Member] | Corporate securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Investments, Fair Value Disclosure	$133,684	$109,179

INVENTORIES_Details

INVENTORIES (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Inventory Disclosure [Abstract]	'	'
Raw materials	$11,257	$8,221
Work-in-process	12,207	13,216
Finished goods	24,470	20,798
Total	$47,934	$42,235

GOODWILL_AND_INTANGIBLE_ASSETS2

GOODWILL AND INTANGIBLE ASSETS (Finite Lived Intangible Assets) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Intangible Assets, Net[Abstract]	'	'	'
Finite-Lived Intangible Assets, Gross	$57,519	'	$57,519
Finite-Lived Intangible Assets, Accumulated Amortization	-19,041	'	-17,185
Finite-Lived Intangible Assets, Net	38,478	'	40,334
Amortization of intangibles	1,856	1,842	'
In-process research and developement [Member]	'	'	'
Intangible Assets, Net[Abstract]	'	'	'
Finite-Lived Intangible Assets, Gross	4,690	'	4,690
Finite-Lived Intangible Assets, Net	4,690	'	4,690
Technology licenses [Member]	'	'	'
Intangible Assets, Net[Abstract]	'	'	'
Finite-Lived Intangible Assets, Gross	3,000	'	3,000
Finite-Lived Intangible Assets, Accumulated Amortization	-2,400	'	-2,325
Finite-Lived Intangible Assets, Net	600	'	675
Patent rights [Member]	'	'	'
Intangible Assets, Net[Abstract]	'	'	'
Finite-Lived Intangible Assets, Gross	1,949	'	1,949
Finite-Lived Intangible Assets, Accumulated Amortization	-1,949	'	-1,949
Finite-Lived Intangible Assets, Net	0	'	0
Developed technology [Member]	'	'	'
Intangible Assets, Net[Abstract]	'	'	'
Finite-Lived Intangible Assets, Gross	26,670	'	26,670
Finite-Lived Intangible Assets, Accumulated Amortization	-5,893	'	-5,247
Finite-Lived Intangible Assets, Net	20,777	'	21,423
Customer relationships [Member]	'	'	'
Intangible Assets, Net[Abstract]	'	'	'
Finite-Lived Intangible Assets, Gross	17,610	'	17,610
Finite-Lived Intangible Assets, Accumulated Amortization	-5,349	'	-4,664
Finite-Lived Intangible Assets, Net	12,261	'	12,946
Tradename [Member]	'	'	'
Intangible Assets, Net[Abstract]	'	'	'
Finite-Lived Intangible Assets, Gross	3,600	'	3,600
Finite-Lived Intangible Assets, Accumulated Amortization	-3,450	'	-3,000
Finite-Lived Intangible Assets, Net	$150	'	$600
Minimum [Member]	'	'	'
Intangible Assets, Net[Abstract]	'	'	'
Amortization useful life range	'2 years	'	'
Maximum [Member]	'	'	'
Intangible Assets, Net[Abstract]	'	'	'
Amortization useful life range	'12 years	'	'

GOODWILL_AND_INTANGIBLE_ASSETS3

GOODWILL AND INTANGIBLE ASSETS (Future Amortization Expense) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Finite-Lived Intangible Assets [Line Items]	'		'
Finite-Lived Intangible Assets, Gross	$57,519		$57,519
Finite-Lived Intangible Assets, Future Amortization Expense [Abstract]	'		'
2014 (remaining 9 months)	4,216		'
2015	5,009		'
2016	4,394		'
2017	3,994		'
2018	3,746		'
Thereafter	12,429		'
Total	33,788	[1]	'
In-process research and developement [Member]	'		'
Finite-Lived Intangible Assets [Line Items]	'		'
Finite-Lived Intangible Assets, Gross	$4,690		$4,690
[1]	The total above excludes $4.7 million of in-process research and development that will be amortized upon completion of development over the estimated useful life of the technology.

SIGNIFICANT_CUSTOMERS_AND_EXPO2

SIGNIFICANT CUSTOMERS AND EXPORT SALES (Customer and Credit Risk Concentration) (Details)

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

segments

Sales Revenue, Goods, Net [Member]

Sales Revenue, Goods, Net [Member]

Sales Revenue, Goods, Net [Member]

Sales Revenue, Goods, Net [Member]

Sales Revenue, Goods, Net [Member]

Sales Revenue, Goods, Net [Member]

Sales Revenue, Goods, Net [Member]

Accounts Receivable [Member]

Accounts Receivable [Member]

Accounts Receivable [Member]

Accounts Receivable [Member]

Accounts Receivable [Member]

Accounts Receivable [Member]

Accounts Receivable [Member]

Accounts Receivable [Member]

Less than [Member]

Customer Concentration Risk [Member]

Customer Concentration Risk [Member]

Customer Concentration Risk [Member]

Customer Concentration Risk [Member]

Customer Concentration Risk [Member]

Customer Concentration Risk [Member]

Customer Concentration Risk [Member]

Credit Concentration Risk [Member]

Credit Concentration Risk [Member]

Credit Concentration Risk [Member]

Credit Concentration Risk [Member]

Credit Concentration Risk [Member]

Credit Concentration Risk [Member]

Credit Concentration Risk [Member]

Credit Concentration Risk [Member]

Sales Revenue, Goods, Net [Member]

customers

customers

Customer A [Member]

Customer A [Member]

Customer B [Member]

Ten Customers [Member]

Ten Customers [Member]

customers

customers

Customer A [Member]

Customer A [Member]

Customer B [Member]

Customer B [Member]

Ten Customers [Member]

Ten Customers [Member]

Customer Concentration Risk [Member]

Customer B [Member]

Concentration Risk [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of reportable segment

1

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of major customers

'

10

10

'

'

'

'

'

10

10

'

'

'

'

'

'

'

Concentration risk, percentage of total net revenues

'

'

'

19.00%

19.00%

10.00%

59.00%

58.00%

'

'

'

'

'

'

'

'

0.00%

[1]

Concentration risk percentage benchmark for total net reveunes

'

10.00%

10.00%

'

'

'

'

'

'

'

27.00%

21.00%

11.00%

17.00%

67.00%

71.00%

'

Concentration risk percentage benchmark for accounts receivable

'

'

'

'

'

'

'

'

10.00%

10.00%

'

'

'

'

'

'

'

[1]

Total customer revenue was less than 10% of net revenues.

SIGNIFICANT_CUSTOMERS_AND_EXPO3

SIGNIFICANT CUSTOMERS AND EXPORT SALES (International Sales) (Details) (Geographic Concentration Risk [Member], Sales Revenue, Goods, Net [Member])	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Revenue from External Customers [Line Items]	'	'
Concentration risk, percentage of total net revenues	95.00%	95.00%
Hong Kong/China [Member]	'	'
Revenue from External Customers [Line Items]	'	'
Concentration risk, percentage of total net revenues	44.00%	44.00%
Taiwan [Member]	'	'
Revenue from External Customers [Line Items]	'	'
Concentration risk, percentage of total net revenues	16.00%	15.00%
Korea [Member]	'	'
Revenue from External Customers [Line Items]	'	'
Concentration risk, percentage of total net revenues	11.00%	13.00%
Western Europe (excluding Germany) [Member]	'	'
Revenue from External Customers [Line Items]	'	'
Concentration risk, percentage of total net revenues	11.00%	12.00%
Japan [Member]	'	'
Revenue from External Customers [Line Items]	'	'
Concentration risk, percentage of total net revenues	6.00%	5.00%
Singapore [Member]	'	'
Revenue from External Customers [Line Items]	'	'
Concentration risk, percentage of total net revenues	2.00%	3.00%
Germany [Member]	'	'
Revenue from External Customers [Line Items]	'	'
Concentration risk, percentage of total net revenues	2.00%	2.00%
Other [Member]	'	'
Revenue from External Customers [Line Items]	'	'
Concentration risk, percentage of total net revenues	3.00%	1.00%

SIGNIFICANT_CUSTOMERS_AND_EXPO4

SIGNIFICANT CUSTOMERS AND EXPORT SALES (Product Sales) (Details) (Product Concentration Risk [Member], Sales Revenue, Goods, Net [Member])	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Consumer [Member]	'	'
Revenue from External Customer [Line Items]	'	'
Concentration risk, percentage of total end market net revenue	37.00%	36.00%
Communications [Member]	'	'
Revenue from External Customer [Line Items]	'	'
Concentration risk, percentage of total end market net revenue	18.00%	22.00%
Industrial [Member]	'	'
Revenue from External Customer [Line Items]	'	'
Concentration risk, percentage of total end market net revenue	35.00%	32.00%
Computer [Member]	'	'
Revenue from External Customer [Line Items]	'	'
Concentration risk, percentage of total end market net revenue	10.00%	10.00%

EARNINGS_PER_SHARE_Details

EARNINGS PER SHARE (Details) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013
Basic earnings per share:	'		'
Net income	$12,363		$10,903
Weighted-average common shares	30,239,000		28,754,000
Basic earnings per share	$0.41		$0.38
Diluted earnings per share:	'		'
Net income	$12,363		$10,903
Weighted-average common shares	30,239,000		28,754,000
Effect of dilutive securities:	'		'
Employee stock plans	928,000	[1]	1,029,000	[1]
Diluted weighted-average common shares	31,167,000	[1]	29,783,000	[1]
Diluted earnings per share	$0.40	[1]	$0.37	[1]
Antidilutive shares attributable to stock-based awards outstanding excluded from computation of diluted earnings per share	'		281,973
[1]	The Company includes the shares underlying performance-based awards in the calculation of diluted earnings per share if the performance conditions have been satisfied as of the end of the reporting period and excludes such shares when the necessary conditions have not been met. The Company has excluded the shares underlying the 2014 and 2013 awards in the 2014 and 2013 calculation, respectively, as those shares were not contingently issuable as of the end of the period.

PROVISION_FOR_INCOME_TAXES_Det

PROVISION FOR INCOME TAXES (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Income Tax Examination [Line Items]	'	'	'
Effective income tax rate	4.80%	-17.30%	'
Federal statutory tax rate	35.00%	35.00%	'
Reduction to long term deferred tax asset	$5,686	'	$9,449
Accounting Standards Update 2013-07 [Member]	'	'	'
Income Tax Examination [Line Items]	'	'	'
Reduction to long term deferred tax asset	($4,300)	'	'

LEGAL_PROCEEDINGS_AND_CONTINGE1

LEGAL PROCEEDINGS AND CONTINGENCIES (Details) (USD $)

1 Months Ended

3 Months Ended

1 Months Ended

3 Months Ended

1 Months Ended

0 Months Ended

1 Months Ended

0 Months Ended

In Millions, unless otherwise specified

Feb. 28, 2013

Dec. 31, 2008

Dec. 31, 2009

Nov. 30, 2008

Mar. 31, 2014

31-May-10

Dec. 31, 2012

Feb. 28, 2010

1-May-12

Feb. 28, 2011

Dec. 31, 2008

Oct. 31, 2006

Oct. 31, 2004

31-May-08

Feb. 28, 2014

Nov. 30, 2009

1-May-12

Property Lease Guarantee [Member]

Pending Litigation [Member]

Pending Litigation [Member]

Pending Litigation [Member]

Pending Litigation [Member]

Pending Litigation [Member]

Pending Litigation [Member]

Pending Litigation [Member]

Pending Litigation [Member]

Positive Outcome of Litigation [Member]

Positive Outcome of Litigation [Member]

Positive Outcome of Litigation [Member]

Positive Outcome of Litigation [Member]

Positive Outcome of Litigation [Member]

Positive Outcome of Litigation [Member]

Positive Outcome of Litigation [Member]

Counterclaims [Member]

Patent Infringement Claim One [Member]

Patent Infringement Claim Two [Member]

Patent Infringement Claim Two [Member]

Patent Infringement Claim Two [Member]

Patent Infringement Claim Three [Member]

Patent Infringement Claim Three [Member]

Patent Infringement Claim Four [Member]

Patent Infringment Claim Five [Member]

Patent Infringement Claim One [Member]

Patent Infringement Claim One [Member]

Patent Infringement Claim One [Member]

Patent Infringement Claim One [Member]

Patent Infringement Claim Two [Member]

Patent Infringement Claim Three [Member]

Patent Infringement Claim Three [Member]

Patent Infringment Claim Five [Member]

patents

patents

patents

patents

patents

patents

patents

patents

patents

patents

Gain and Loss Contingencies [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of Patents Added to Infringement Claims

'

'

'

'

'

'

1

'

'

'

'

'

'

'

'

'

'

Number of patents in filed infringement claims

'

'

'

3

'

2

'

4

4

'

'

'

4

3

'

2

5

Damages awarded to the Company

'

'

'

'

'

'

'

'

'

$12.90

$6.10

$34

'

'

$105

'

'

Period for petition for further stay of permanent injunction

'

'90 days

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Potential impact on revenue by patent litigation (as a percentage)

'

'

'

'

0.30%

'

'

'

'

'

'

'

'

'

'

'

'

Number of patents in infringment case deemed unenforceable by Fairchild

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1

'

Number of patents withdrawn from infringement claims

'

'

1

'

'

1

'

'

1

'

'

'

'

'

'

'

'

Number of patents remaining in infringement claims

'

'

2

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Damages sought after the Company

$2.40

'

'

'

'

'

'

$19

'

'

'

'

'

'

'

'

'

RECENT_ACCOUNTING_PRONOUNCEMEN1

RECENT ACCOUNTING PRONOUNCEMENTS Narrative (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
New Accounting Pronouncements or Change in Accounting Principle [Line Items]	'	'
Reduction to long term deferred tax asset	$5,686	$9,449
Reduction to non current income tax payable	2,612	6,885
Accounting Standards Update 2013-07 [Member]	'	'
New Accounting Pronouncements or Change in Accounting Principle [Line Items]	'	'
Reduction to long term deferred tax asset	-4,300	'
Reduction to non current income tax payable	($4,300)	'

BANK_LINE_OF_CREDIT_Details

BANK LINE OF CREDIT (Details) (USD $)	Mar. 31, 2014	Jul. 05, 2012
Line of Credit Facility [Line Items]	'	'
Number of banks used for Credit Agreement	'	2
Line of Credit [Member]	'	'
Line of Credit Facility [Line Items]	'	'
Credit Agreement, maximum borrowing capacity	'	$100,000,000
Letters of credit outstanding	0	'
Line of credit sublimit for issuance of letters of credit [Member]	'	'
Line of Credit Facility [Line Items]	'	'
Credit Agreement, maximum borrowing capacity	'	$20,000,000