Thoratec 10-Q 31 Oct 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 28, 2013	Oct. 25, 2013
Document and Entity Information	'	'
Entity Registrant Name	'THORATEC CORP	'
Entity Central Index Key	'0000350907	'
Document Type	'10-Q	'
Document Period End Date	28-Sep-13	'
Amendment Flag	'false	'
Current Fiscal Year End Date	'--12-28	'
Entity Current Reporting Status	'Yes	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	56,970,534
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (USD $)	Sep. 28, 2013	Dec. 29, 2012
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$102,843	$101,322
Short-term available-for-sale investments	176,005	148,426
Receivables, net of allowances of $1,962 and $2,127, respectively	66,990	70,471
Inventories	66,164	47,100
Deferred tax assets	11,115	10,626
Income tax receivable	9,014	11,950
Prepaid expenses and other assets	6,271	7,162
Total current assets	438,402	397,057
Property, plant and equipment, net	54,707	45,892
Goodwill	204,293	194,182
Purchased intangible assets, net	38,882	33,571
Long-term available-for-sale investments	4,160	10,607
Other long-term assets	18,354	17,055
Total Assets	758,798	698,364
Current liabilities:	'	'
Accounts payable	19,322	19,959
Accrued compensation	22,802	25,409
Contingent liabilities, current portion	7,407	4,220
Other accrued liabilities	21,847	19,098
Total current liabilities	71,378	68,686
Long-term deferred tax liability	1,761	2,780
Other long-term liabilities	10,071	12,323
Contingent liabilities, non-current portion	33,138	17,832
Total Liabilities	116,348	101,621
Shareholders' equity:	'	'
Common shares: no par, authorized 100,000; issued and outstanding 56,871 and 57,584 as of September 28, 2013 and December 29, 2012, respectively	'	'
Additional paid-in capital	598,402	577,448
Retained earnings	57,726	34,364
Accumulated other comprehensive loss	-13,678	-15,069
Total Shareholders' Equity	642,450	596,743
Total Liabilities and Shareholders' Equity	$758,798	$698,364

CONDENSED_CONSOLIDATED_BALANCE1

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Sep. 28, 2013	Dec. 29, 2012
In Thousands, except Per Share data, unless otherwise specified
CONDENSED CONSOLIDATED BALANCE SHEETS	'	'
Receivables, allowances (in dollars)	$1,962	$2,127
Common shares, par value (in dollars per share)	$0	$0
Common shares, authorized	100,000	100,000
Common shares, issued	56,871	57,584
Common shares, outstanding	56,871	57,584

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS	'	'	'	'
Product sales	$126,444	$117,768	$374,648	$363,196
Cost of product sales	40,958	36,162	117,031	111,071
Gross profit	85,486	81,606	257,617	252,125
Operating expenses:	'	'	'	'
Selling, general and administrative	37,679	28,478	107,348	91,692
Research and development	25,469	20,382	71,488	59,886
Total operating expenses	63,148	48,860	178,836	151,578
Income from operations	22,338	32,746	78,781	100,547
Other income and (expense):	'	'	'	'
Interest expense and other	'	'	-4	-3
Interest income and other	569	579	1,899	1,401
Income before income taxes	22,907	33,325	80,676	101,945
Income tax expense	-4,003	-9,070	-20,413	-31,396
Net income	$18,904	$24,255	$60,263	$70,549
Net Income per share:	'	'	'	'
Basic (in dollars per share)	$0.33	$0.41	$1.05	$1.20
Diluted (in dollars per share)	$0.32	$0.41	$1.03	$1.18
Shares used to compute income per share:	'	'	'	'
Basic (in shares)	57,427	58,762	57,447	58,645
Diluted (in shares)	58,234	59,669	58,400	59,609

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME	'	'	'	'
Net income	$18,904	$24,255	$60,263	$70,549
Other comprehensive income, net of tax:	'	'	'	'
Unrealized gains on investments (net of taxes of $1,225 and $297 for the three months ended September 28, 2013 and September 29, 2012, respectively, and $1,230 and $718 for the nine months ended September 28, 2013 and September 29, 2012, respectively)	1,858	436	1,851	1,061
Foreign currency translation adjustments, net of tax	1,216	1,188	-460	1,353
Total other comprehensive income, net of tax	3,074	1,624	1,391	2,414
Comprehensive income	$21,978	$25,879	$61,654	$72,963

CONDENSED_CONSOLIDATED_STATEME2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME	'	'	'	'
Unrealized gains on investments, taxes	$1,225	$297	$1,230	$718

CONDENSED_CONSOLIDATED_STATEME3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012
Cash flows from operating activities:	'	'
Net income	$60,263	$70,549
Adjustments to reconcile net income to net cash provided by operating activities:	'	'
Depreciation and amortization	13,841	14,621
Fixed assets impairment	1,961	'
Investment premium amortization, net	2,557	1,628
Allowance for bad debt	-199	'
Change in fair value of contingent consideration	3,913	'
Non-cash interest income (expense) and other	-151	-1,623
Tax benefit related to stock options	1,551	2,200
Share-based compensation expense	20,226	16,033
Excess tax benefits from share-based compensation	-1,750	-2,212
Loss on disposal of assets	70	57
Change in net deferred tax liability	-515	-4,152
Changes in assets and liabilities:	'	'
Receivables	3,957	-2,021
Inventories	-20,578	5,220
Other current and non-current assets	1,499	-4,525
Accounts payable	-92	2,668
Income taxes, net	-1,650	1,708
Other current and non-current liabilities	1,548	9,052
Net cash provided by operating activities	86,451	109,203
Cash flows from investing activities:	'	'
Purchases of available-for-sale investments	-132,351	-128,080
Sales and maturities of available-for-sale investments	108,019	134,216
Acquisition of a business	-13,000	'
Purchases of property, plant and equipment, net	-6,916	-7,308
Net cash used in investing activities	-44,248	-1,172
Cash flows from financing activities:	'	'
Payment of contingent consideration	-4,220	-1,518
Proceeds from stock option exercises	6,635	5,222
Proceeds from stock issued under employee stock purchase plan	2,536	1,896
Excess tax benefits from share-based compensation	1,750	2,212
Repurchase and retirement of common shares	-47,089	-10,372
Net cash used in financing activities	-40,388	-2,560
Effect of exchange rate changes on cash and cash equivalents	-294	-94
Net increase in cash and cash equivalents	1,521	105,377
Net cash and cash equivalents at beginning of period	101,322	42,661
Net cash and cash equivalents at end of period	102,843	148,038
Supplemental disclosure of consolidated cash flow information:	'	'
Cash paid for income taxes	21,237	31,589
Cash paid for interest	4	3
Supplemental disclosure of consolidated non-cash investing and financing activities:	'	'
Transfers of equipment from inventory	1,754	2,406
Purchases of property, plant and equipment through accounts payable and accrued liabilities	670	1,206
Acquisition of DuraHeart II:	'	'
Contingent consideration included in contingent liabilities, non-current portion	$18,800	'

Operations_and_Significant_Acc

Operations and Significant Accounting Policies	9 Months Ended
	Sep. 28, 2013
Operations and Significant Accounting Policies	'
Operations and Significant Accounting Policies	'
	Note 1. Operations and Significant Accounting Policies
	Basis of Presentation
	The interim unaudited condensed consolidated financial statements of Thoratec Corporation (“we,” “our,” “us,” or the “Company”) have been prepared and presented in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and the rules and regulations of the Securities and Exchange Commission (“SEC”), without audit, and reflect all adjustments necessary (consisting only of normal recurring adjustments) to present fairly our financial position, results of operations and cash flows as of and for the periods presented. Certain information and footnote disclosures normally included in our annual financial statements, prepared in accordance with GAAP, have been condensed or omitted. The accompanying financial statements should be read in conjunction with our fiscal 2012 consolidated financial statements, and the accompanying notes thereto, filed with the SEC in our 2012 Annual Report on Form 10-K for the fiscal year ended December 29, 2012 (the “2012 Annual Report”). The operating results for any interim period are not necessarily indicative of the results that may be expected for any future period.
	The preparation of our unaudited condensed consolidated financial statements necessarily requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities on the unaudited condensed consolidated balance sheet dates and the reported amounts of revenues and expenses for the periods presented.  The actual amounts could differ from those estimated amounts.

Acquisition_of_DuraHeart_II

Acquisition of DuraHeart II	9 Months Ended
	Sep. 28, 2013
Acquisition of DuraHeart II	'
Acquisition of DuraHeart II	'
	Note 2.  Acquisition of DuraHeart II
	On June 30, 2013, we acquired certain assets and assumed certain liabilities from Terumo Corporation (“Terumo”) related to the DuraHeart II Left Ventricular Assist System product line (DuraHeart II) previously under development by Terumo.  Under the terms of the acquisition, we made an upfront cash payment to Terumo of $13.0 million, and will be obligated to make potential future milestone payments, based on regulatory approvals and product sales, of up to $43.5 million. Terumo also maintains the right to repurchase the Purchased Assets in the event that Thoratec does not fulfill certain conditions relating to the development of the DuraHeart II by August 2016. As part of the agreement, a team of Terumo employees transferred to Thoratec. Additionally, Thoratec and Terumo entered into a distribution partnership, in which Terumo will commercialize DuraHeart II in Japan and potentially other parts of Asia, if and when local regulatory approvals are obtained. DuraHeart II is an ultra-compact, full-support, centrifugal flow chronic ventricular assist system that uses a unique technology foundation known as “force balance” suspension. The device uses magnetic forces, balanced by hydrodynamic support, to achieve consistent gaps across the operating range of the pump, independent of pump speed. The primary reasons for the acquisition were to diversify the technology platforms within the Company’s research and development portfolio and to apply the Company’s resources and expertise in mechanical circulatory support to advance DuraHeart II through product development and clinical trials.
	The DuraHeart II acquisition was accounted for as a business combination. In connection with the acquisition, we recorded $2.0 million of acquisition-related costs, which were recognized in our condensed consolidated statement of operations for the nine months ended September 28, 2013 within operating expenses. We also recorded $9.9 million of goodwill, equal to the amount by which the purchase consideration exceeded the fair value of the acquired assets. This goodwill was allocated to our sole operating segment (Cardiovascular) and is deductible for U.S. income tax purposes. The operating results of the DuraHeart II product line from the date of acquisition, including zero revenue and $1.5 million net loss, are included in our condensed consolidated statement of operations for the nine month period ended September 28, 2013.
	We will be obligated to pay potential post-closing cash milestone payments of $5.5 million and $10.5 million upon Conformité Européene (“CE”) Mark approval in Europe and U.S. Food and Drug Administration (“FDA”) approvals, respectively, for the DuraHeart II device currently under development (collectively referred to as the “regulatory milestones”). Additional milestone payments totaling $27.5 million will become payable by us upon reaching various commercial sale milestones after the regulatory approvals are obtained (referred to as the “commercial sales milestones”). The fair value of the combined contingent consideration due upon achievement of the regulatory milestones and the commercial sales milestones was estimated to be $18.8 million at the acquisition closing date and has been recorded as a non-current liability, because such contingent consideration is expected to be settled no earlier than 2016.
	Total purchase price consideration was as follows (in thousands):
	Cash paid at the acquisition closing date (June 30, 2013)	$	13,000
	Estimated fair value of contingent consideration	18,800
	Total estimated purchase price	$	31,800
	We determined the initial fair value of the contingent consideration in connection with the regulatory and commercial sales milestones using various estimates, including probabilities of success, discount rates and the estimated amount of time until the conditions of the milestone payments are met. This fair value measurement is based on significant inputs not observable in the market, representing a Level 3 measurement within the fair value hierarchy (see Note 3 for more information about fair value measurements). The key assumptions used to determine the fair value of the contingent consideration in connection with the regulatory milestones include a 5.3% discount rate and probability adjusted milestone payment date ranges from July 2016 to January 2020. The key assumptions used to determine the fair value of contingent consideration in connection with the commercial sales milestones include a 20.0% discount rate and probability-weighted expected milestone payment date ranges from July 2019 to January 2029, based on the aggregate number of commercial units sold (starting at the 500th unit sold to the 10,000th unit sold). As of September 28, 2013, there were no significant changes in the range of outcomes for the contingent consideration recognized as a result of the acquisition, although the fair value of the contingent consideration for regulatory and commercial sales milestone payments increased by $0.1 million and $0.2 million, respectively, as a result of the passage of time as development work progressed towards the achievement of the milestones, which were recorded within operating expense.
	Preliminary Purchase Price Allocation as of the acquisition date is summarized as follows (in thousands):
	Property, plant and equipment	$	8,900
	Identifiable intangible assets:
	Favorable lease contract	600
	In-process research and development	12,400
	Goodwill	9,900
	Total estimated purchase price consideration	31,800
	Less: Contingent consideration	18,800
	Cash paid at the acquisition closing	$	13,000
	We recorded an In-Process Research & Development (IPR&D) asset in the amount of $12.4 million, which represents an estimate of the fair value of in-process technology related to the DuraHeart II device. The estimated fair value was determined using the multi-period excess earnings method, a variation of the income approach. The multi-period excess earnings method estimates the value of an intangible asset equal to the present value of the incremental after-tax cash flows attributable to that intangible asset. The fair value using the multi-period excess earnings method was dependent on an estimated weighted average cost of capital of 22.5%, which represents a rate of return that a market participant would expect for these assets.
	Pursuant to accounting standards for business combination, intangible assets related to IPR&D assets are considered to be indefinite-lived until the completion or abandonment of the associated research and development efforts. Accordingly, amortization of the IPR&D will not occur until it reaches market feasibility. During the period the assets are considered indefinite-lived, they will be tested for impairment on an annual basis, as well as between annual tests if we become aware of any events occurring or changes in circumstances that would indicate that the fair values of the IPR&D projects are less than their respective carrying amounts. If and when development is complete, which generally occurs when regulatory approval to market a product is obtained, the associated assets would be deemed definite-lived and would then be amortized based on their estimated useful lives at that point in time. Costs incurred in connection with this project subsequent to the date of acquisition will be expensed as incurred. If the related project is terminated or abandoned, we may have an impairment related to the IPR&D, calculated as the excess of the asset’s carrying value over its fair value.
	Pro forma financial information (unaudited)
	The following unaudited pro forma information presents the combined results of operations for the nine months ended September 28, 2013 and September 29, 2012 as if the DuraHeart II acquisition had been completed as of the beginning of 2012. Actual 2013 acquisition-related transaction costs of $2.0 million were excluded from the 2013 pro forma results below and included in the 2012 pro forma results as if these costs were incurred during the 2012 period. All other adjustments to the pro forma results in 2013 and 2012 were not significant.
		Nine Months Ended		Nine Months Ended
		September 28, 2013		September 29, 2012
		(in thousands)
	Product sales	$	374,648	$	363,196
	Income before taxes	65,922		77,691
	Net income	49,242		53,764
	The pro forma results do not reflect operating efficiencies or potential cost savings which may result from the consolidation of operations.

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 28, 2013
Fair Value Measurements	'
Fair Value Measurements	'
	Note 3. Fair Value Measurements
	Our financial assets and liabilities carried at fair value are primarily comprised of investments in money market funds, certificates of deposit, municipal and corporate bonds, commercial paper, variable demand notes, auction rate securities, forward contracts, certain investments held as assets under the deferred compensation plan, marketable equity securities, and the contingent consideration. The fair value accounting guidance requires that assets and liabilities be carried at fair value and classified in one of the following three categories:
	Level 1: Quoted prices in active markets for identical assets or liabilities that the Company has the ability to access
	Level 2: Observable market based inputs or unobservable inputs that are corroborated by market data such as quoted prices, interest rates and yield curves
	Level 3: Inputs that are unobservable data points that are not corroborated by market data
	We review the fair value hierarchy classification on a quarterly basis. Changes in the ability to observe valuation inputs may result in a reclassification of levels of certain securities within the fair value hierarchy. We recognize transfers into and out of levels within the fair value hierarchy in the period in which the actual event or change in circumstances that caused the transfer occurs. There were no transfers between Level 1, Level 2, and Level 3 during either of the three or the nine months ended September 28, 2013 or the three or nine months ended September 29, 2012.
	The following table represents the fair value hierarchy for our financial assets and financial liabilities measured at fair value on a recurring basis:
		Total Fair			Quoted			Significant			Significant
		Value			Prices in			Other			Unobservable
					Active			Observable			Inputs
					Markets			Inputs			(Level 3)
					(Level 1)			(Level 2)
		(in thousands)
	As of September 28, 2013:
	Cash equivalents:
	Money market funds	$	78,501		$	78,501		$	—		$	—
	Commercial paper	10,599			—			10,599			—
	Municipal bonds	793			—			793			—
	Short-term investments:
	Municipal bonds	144,997			—			144,997			—
	Variable demand notes	7,700			—			7,700			—
	Corporate bonds	5,512			—			5,512			—
	Commercial paper	10,997			—			10,997			—
	Certificate of deposit	2,000						2,000			—
	Auction rate securities	4,800			—			—			4,800
	Prepaid expenses and other assets:
	Foreign exchange contracts	369			—			369			—
	Long-term investments:
	Auction rate securities	4,160			—			—			4,160
	Other long-term assets:
	Investments included in our deferred compensation plan	1,838			—			1,838			—
	Marketable equity securities	5,115			5,115			—			—
	Other accrued liabilities:
	Foreign exchange contracts	1,408			—			1,408			—
	Contingent consideration (current and long-term portions)	$	40,545		$	—		$	—		$	40,545
		Total Fair			Quoted			Significant			Significant
		Value			Prices in			Other			Unobservable
					Active			Observable			Inputs
					Markets			Inputs			(Level 3)
					(Level 1)			(Level 2)
		(in thousands)
	As of December 29, 2012:
	Cash equivalents:
	Money market funds	$	59,230		$	59,230		$	—		$	—
	Commercial paper	4,998			—			4,998			—
	Municipal bonds	3,045			—			3,045			—
	Corporate bonds	380			—			380			—
	Short-term investments:
	Municipal bonds	107,533			—			107,533			—
	Variable demand notes	21,330			—			21,330			—
	Corporate bonds	12,258			—			12,258			—
	Commercial paper	5,299			—			5,299			—
	Certificate of deposit	2,006			—			2,006			—
	Prepaid expenses and other assets:
	Foreign exchange contracts	16			—			16			—
	Long-term investments:
	Auction rate securities	10,607			—			—			10,607
	Other long-term assets:
	Investments included in our deferred compensation plan	1,731			—			1,731			—
	Marketable equity securities	2,602			2,602			—			—
	Other accrued liabilities:
	Foreign exchange contracts	380			—			380			—
	Contingent consideration (current and long-term portions)	$	22,052		$	—		$	—		$	22,052
Financial assets and liabilities are considered Level 2 when their fair values are determined using inputs that are observable in the market or can be derived principally from or corroborated by observable market data such as pricing for similar securities, recently executed transactions, cash flow models with yield curves, and benchmark securities. Our Level 2 financial assets and liabilities include short-term investments, foreign exchange instruments and certain of our deferred compensation plan securities. In addition, Level 2 financial instruments are valued using comparisons to like-kind financial instruments and models that use readily observable market data as their basis.
Financial assets and liabilities are considered Level 3 when their fair values are determined using pricing models, discounted cash flow methodologies, or similar techniques, and at least one significant model assumption or input is unobservable. Level 3 financial assets and liabilities include the following:
·                  Auction rate securities — Due to limited market activity the determination of fair value requires significant judgment or estimation. The auction rate securities were valued using a discounted cash-flow model over a five-year period based on estimated interest rates, the present value of future principal payments, and interest payments discounted at rates considered to reflect the current market conditions and the credit quality of auction rate securities.
·                  Contingent consideration — The fair value of the contingent consideration related to the acquisition of the medical business of Levitronix LLC (Levitronix Medical) in August 2011 requires significant management judgment or estimation and is calculated using the income approach, using various revenue assumptions and applying a probability to each outcome. The fair value of the contingent consideration is remeasured at the estimated fair value at each reporting period with the change in fair value recorded within operating expense within our consolidated statements of operations. Actual amounts paid may differ from the obligations recorded. The accretion of interest expense was not significant for all periods presented. Refer to Note 2 for a discussion of the fair value of the DuraHeart II contingent consideration.
Available-for-sale investments are carried at fair value and are included in the tables above under short- and long-term investments. The aggregate fair value, amortized cost basis and gross unrealized gains and losses of available-for-sale investments by major security type were as follows:
	Amortized			Gross			Gross			Fair
	Cost			Unrealized			Unrealized			Value
				Gains			Losses
	(in thousands)
As of September 28, 2013:
Short-term investments:
Municipal bonds	$	144,848		$	172		$	(23	)	$	144,997
Variable demand notes	7,700			—			—			7,700
Corporate bonds	5,508			6			(2		)	5,512
Commercial paper	10,996			—			—			10,996
Certificate of deposit	2,000			—			—			2,000
Auction rate securities	4,800			—			—			4,800
Total short-term investments	$	175,852		$	178		$	(25	)	$	176,005
Long-term investments:
Auction rate securities	$	4,900		$	—		$	(740	)	$	4,160
Other long-term assets:
Marketable equity securities	2,996			2,119			—			5,115
Total long-term	$	7,896		$	2,119		$	(740	)	$	9,275
As of December 29, 2012:
Short-term investments:
Municipal bonds	$	107,416		$	136		$	(19	)	$	107,533
Variable demand notes	21,330			—			—			21,330
Corporate bonds	12,244			17			(3		)	12,258
Commercial paper	5,298			1			—			5,299
Certificate of deposit	2,000			6			—			2,006
Total short-term investments	$	148,288		$	160		$	(22	)	$	148,426
Long-term investments:
Auction rate securities	$	11,900		$	—		$	(1,293	)	$	10,607
Other long-term assets:
Marketable equity securities (A)	2,996			—			(394		)	2,602
Total long-term	$	14,896		$	—		$	(1,687	)	$	13,209
(A)       As of December 29, 2012, our available-for-sale equity securities have been in a continuous loss position for less than 12 months.
As of September 28, 2013, we owned approximately $9.7 million face amount of auction rate securities. The assets underlying these investments are student loans backed by the U.S. government under the Federal Family Education Loan Program or by private insurers and are rated between A and BBB. Historically, these securities have provided liquidity through a Dutch auction process that resets the applicable interest rate periodically every seven to 35 days. Beginning in February of 2008, these auctions began to fail. The principal amount of these auction rate securities will not be accessible until future auctions for these securities are successful, a secondary market is established, these securities are called for redemption, or they are paid at maturity.
As of September 28, 2013, we had recorded an estimated cumulative unrealized loss of $0.7 million ($0.4 million, net of tax) related to the temporary impairment of the auction rate securities, which was included in accumulated other comprehensive income (loss) within the consolidated shareholders’ equity. In addition, our management reviews impairments and credit loss associated with our investments, including auction rate securities, to determine the classification of the impairment as “temporary” or “other-than-temporary” and to bifurcate the credit and non-credit component of an other-than-temporary impairment event. We (i) do not intend to sell any of the auction rate securities prior to maturity at an amount below the original purchase value; (ii) intend to hold the investment to recovery and, based on a more-likely-than-not probability assessment, will not be required to sell the security before recovery; and (iii) deem that it is not probable that we will receive less than 100% of the principal and accrued interest from the issuer. Therefore, 100% of the impairment was charged to other comprehensive income (loss). In the nine months ended September 28, 2013, we liquidated at par value $2.2 million of our auction rate securities. In September 2013, $4.8 million of our auction rate securities were called at par and were subsequently settled in October 2013. We have reported the $4.8 million within short-term investments as of September 28, 2013, with the remaining $4.2 million classified as long-term available-for-sale investments. We will continue to liquidate investments in auction rate securities as opportunities arise.
If the issuers of the auction rate securities are unable to successfully complete future auctions and their credit ratings deteriorate, then we may in the future be required to record the other-than-temporary impairment charges to the consolidated statement of operations. It could conceivably take until the final maturity of the underlying notes (up to 30 years) to realize the investments’ fair value.
Our deferred compensation plan includes our corporate owned life insurance policies and mutual fund investments. The underlying mutual fund investments are deemed trading securities. The mutual fund investments’ fair value and the cash surrender value of our corporate-owned life insurance policies are classified in the condensed consolidated balance sheets in “Other long-term assets.” The aggregate value of our deferred compensation plan assets was as follows:
	September 28,			December 29,
	2013			2012
	(in thousands)
Deferred compensation plan	$	5,216		$	4,225
The unrealized gain before tax from the change in the value of the deferred compensation plan was $0.4 million and $0.3 million in the nine months ended September 28, 2013 and September 29, 2012, respectively.
The amortized cost and fair value of available-for-sale debt investments, by contractual maturity, were as follows as of September 28, 2013:
	Amortized			Fair
	Cost			Value
	(in thousands)
Maturing within 1 year	$	139,211		$	139,302
Maturing after 1 year through 5 years	36,641			36,703
Short-term available-for-sale investments	175,852			176,005
Maturing after 5 years	4,900			4,160
	$	180,752		$	180,165
The following table provides a roll forward of the fair value, as determined by Level 3 inputs, of the auction rate securities during the nine months ended September 28, 2013:
	Auction
	Rate
	Securities
	(in thousands)
Balance as of December 29, 2012	$	10,607
Settlements at par	(2,200		)
Unrealized gain on auction rate securities, included in other comprehensive income	553
Balance as of September 28, 2013	8,960
Less: Reported within short-term available-for-sale investments	(4,800		)
Total long-term available-for-sale investments	$	4,160
We continue to monitor the market for auction rate securities and consider its impact (if any) on the fair value of our investments. If the current market conditions deteriorate further, or the anticipated recovery in fair values does not occur, we may be required to record additional unrealized losses in other comprehensive income or other-than-temporary impairment charges to the condensed consolidated statements of operations in future periods.
The following table provides a roll forward of the fair value, as determined by Level 3 inputs, of contingent consideration during the nine months ended September 28, 2013:
	Levitronix Medical			DuraHeart II			Total
	Acquisition			Acquisition			Contingent
							Consideration
	(in thousands)
Balance as of December 29, 2012	$	22,052		$	—		$	22,052
Additions (See Note 2)	—			18,800			18,800
Payments	(4,220		)	—			(4,220		)
Change in fair value	3,647			266			3,913
Balance as of September 28, 2013	$	21,479		$	19,066		$	40,545
The following table presents quantitative information about the inputs and valuation methodologies used for our fair value measurements classified in Level 3 of the fair value hierarchy as of September 28, 2013:
	Fair Value at			Valuation Methodology		Significant Unobservable Input		Weighted Average
	September 28,							(range, if applicable)
	2013
	(in thousands)
Auction rate securities	$	8,960		Discounted cash flow		Discount rate		1.40%
						Market credit spread		3.15%
						Liquidity factor		0.00%
Levitronix Medical Contingent consideration	$	21,479		Multiple outcome discounted cash flow		Annual Revenue		$ 42.3 million ($29.6 million to $48.2 million)
						Discount rate		1.04% (0.8% to 1.39%)
						Probability of occurrence		20% (10% to 50%)
DuraHeart II Contingent consideration	$	19,066		Multiple outcome discounted cash flow		Milestone dates		2016 to 2029
						Discount rate		5.3% to 20.0%
						Probability of occurrence		1% to 50%
Auction rate securities
The significant unobservable inputs used in the fair value measurement of the auction rate securities are the weighted average discount rate, market credit spread and liquidity factor. A significant increase (decrease) in the discount rate in isolation could result in a significantly higher (lower) fair value measurement, whereas a significant increase (decrease) in the market credit spread and liquidity factor in isolation could result in a significantly lower (higher) fair value measurement. Although the discount rate as compared to the market credit spread and liquidity factors are not directly related, they will generally move in opposite directions.
The fair value of auction rate securities is calculated on a quarterly basis by senior management based on a collaborative effort of the corporate treasury and accounting groups. To assess the reasonableness of the fair value measurement, management compares its fair value measurement to the values calculated by independent third parties.
Contingent consideration
The estimated fair value of the liability for contingent consideration represents revenue and milestone targets related to our Levitronix Medical and DuraHeart II acquisitions, respectively. The fair value of the liability is determined using a discounted cash flow methodology with significant inputs that include projected revenue, discount rate and percentage probability of occurrence for the Levitronix Medical contingent consideration; and regulatory milestone targets, commercial milestones targets, discount rate and percent probability of occurrence of these milestones for the DuraHeart II contingent consideration. A significant increase (decrease) in the projected revenue in isolation could result in a significantly higher (lower) fair value measurement; a significant delay (acceleration) in the projected regulatory milestone achievement date in isolation could result in a significantly lower (higher) fair value measurement; a significant increase (decrease) in the discount rate in isolation could result in a significantly lower (higher) fair value measurement; and the changes in the probability of occurrence between the outcomes in isolation could result in a significantly lower (higher) fair value measurement.
The fair value of the contingent consideration is calculated on a quarterly basis by management based on a collaborative effort of our regulatory, research and development, operations, finance and accounting groups. Potential valuation adjustments are made as additional information becomes available, including the progress toward achieving revenue and milestone targets as compared to initial projections, the impact of market competition, and changes in actual and projected product mix and average selling price, with the impact of such adjustments being recorded in the condensed consolidated statement of operations. In the three and nine months ended September 28, 2013, we recorded a remeasurement adjustment to the Levitronix and DuraHeart II contingent consideration in the amount of $3.6 million and $0.3 million, respectively. No adjustment was recorded in the nine months ended September 29, 2012.
Assets and Liabilities That Are Measured at Fair Value on a Nonrecurring Basis
Non-financial assets such as goodwill, intangible assets, and property, plant, and equipment are evaluated for impairment and adjusted to fair value using Level 3 inputs, only when an impairment is recognized. Fair values are considered Level 3 when management makes significant assumptions in developing a discounted cash flow model based upon a number of considerations including projections of revenues, earnings and a discount rate. In addition, in evaluating the fair value of goodwill impairment, further corroboration is obtained using our market capitalization. We recorded an impairment charge of $2.0 million related to certain property, plant, and equipment in the nine months ended September 28, 2013. No impairment was recorded in the nine months ended September 29, 2012.

Foreign_Exchange_Instruments

Foreign Exchange Instruments	9 Months Ended
	Sep. 28, 2013
Foreign Exchange Instruments	'
Foreign Exchange Instruments	'
	Note 4. Foreign Exchange Instruments
	We utilize foreign currency forward exchange contracts and options with recognized financial institutions to manage our exposure to the impact of fluctuations in foreign currency exchange rates on certain intercompany balances and foreign currency denominated sales and purchase transactions. We do not use derivative financial instruments for speculative or trading purposes. These forward contracts are not designated as hedging instruments for accounting purposes. Principal hedged currencies include the Euro, British Pound Sterling, and U.S. Dollar. The periods of these forward contracts range up to six months and the notional amounts are intended to be consistent with changes in the underlying exposures. We intend to exchange foreign currencies for U.S. Dollars at maturity.
	Total gross notional amounts for outstanding derivatives instruments were as follows:
		September 28,			December 29,
		2013			2012
	Forward contracts:
	Euro (sell)	€	17.8 million		€	13.9 million
	British Pound Sterling (sell)	£	1.3 million		£	1.8 million
	U.S. Dollar (sell)	$	17.0 million		$	5.3 million
	U.S. Dollar (buy)	$	59.0 million		$	73.5 million
	The following table shows the derivative instruments measured at gross fair value reported on the condensed consolidated balance sheets:
		As of September 28, 2013						As of December 29, 2012
		Prepaid expenses			Other accrued			Prepaid expenses			Other accrued
		and other assets			liabilities			and other assets			liabilities
		(in thousands)
	Derivatives not designated as hedging instruments (forward contracts)	$	369		$	1,408		$	16		$	380
	The following table shows the effect of derivative instruments not designated as hedging instruments and foreign currency transactions gains and losses which were included in “Interest income and other” in the condensed consolidated statements of operations:
		Three Months Ended						Nine Months Ended
		September 28,			September 29,			September 28,			September 29,
		2013			2012			2013			2012
		(in thousands)
	Foreign currency exchange loss on foreign contracts	$	(1,953	)	$	(2,462	)	$	(649	)	$	(130	)
	Foreign currency transactions gain	2,122			2,617			1,114			308

Balance_Sheet_Information

Balance Sheet Information	9 Months Ended
	Sep. 28, 2013
Balance Sheet Information	'
Balance Sheet Information	'
	Note 5. Balance Sheet Information
	The following tables provide details of selected condensed consolidated balance sheets items as of the end of each period:
	Inventories consisted of the following:
		September 28,			December 29,
		2013			2012
		(in thousands)
	Finished goods	$	24,446		$	15,087
	Work in process	14,639			11,020
	Raw materials	27,079			20,993
	Total	$	66,164		$	47,100
	Property, plant and equipment, net consisted of the following:
		September 28,			December 29,
		2013			2012
		(in thousands)
	Land, building and improvements	$	20,594		$	20,543
	Equipment and capitalized software	59,421			46,290
	Furniture and leasehold improvements	22,394			20,933
	Total	102,409			87,766
	Less Accumulated depreciation	(47,702		)	(41,874		)
	Total	$	54,707		$	45,892
	Depreciation expense was $2.0 million and $6.1 million for the three and nine months ended September 28, 2013, respectively, and $2.2 million and $6.4 million for the three and nine months ended September 29, 2012, respectively.
	Warranty provision, included in “Other accrued liabilities” on the condensed consolidated balance sheets, and the changes in the balances for the nine months ended September 28, 2013 and September 29, 2012 were as follows:
		September 28,			September 29,
		2013			2012
		(in thousands)
	Balance, beginning of the period	$	2,212		$	2,452
	Additions	2,982			1,132
	Settlements	(1,666		)	(1,308		)
	Balance, end of the period	$	3,528		$	2,276
	Changes in Accumulated Other Comprehensive Loss by component during the nine months ended September 28, 2013:
		Foreign currency			Unrealized			Total
		items (A)			gain (loss) on
					available-for-sale
					securities (A)
		(in thousands)
	Balance as of December 29, 2012	$	(13,928	)	$	(1,141	)	$	(15,069	)
	Other comprehensive loss before reclassification	(460		)	1,851			1,391
	Amounts reclassified from accumulated other comprehensive loss	—			—			—
	Net current period other comprehensive loss	(460		)	1,851			1,391
	Balance as of September 28, 2013	$	(14,388	)	$	710		$	(13,678	)
	(A)       All amounts are net of tax.

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets, net	9 Months Ended
	Sep. 28, 2013
Goodwill and Intangible Assets, net	'
Goodwill and Intangible Assets, net	'
	Note 6. Goodwill and Intangible Assets, net
	The carrying amount of goodwill and the changes in the balances for the nine months ended September 28, 2013 were as follows (in thousands):
	Balance as of December 29, 2012	$	194,182
	Goodwill addition (See Note 2)	9,900
	Foreign currency translation impact	211
	Balance as of September 28, 2013	$	204,293
	Intangible assets (net of accumulated amortization and impairment) were as follows:
		As of September 28, 2013
		Gross		Accumulated			Accumulated			Net
		Amount		Amortization			Impairment			Amount
		(in thousands)
	Intangible assets subject to amortization:
	Patents and trademarks	$	43,532	$	(34,478	)	$	—		$	9,054
	Core technology	37,180		(22,587		)	(12,642		)	1,951
	Developed technology	128,073		(80,427		)	(37,600		)	10,046
	Pre-existing license agreement	2,300		(712		)	—			1,588
	Customer based relationships and other	7,246		(3,594		)	—			3,652
	Foreign currency translation impact	191		—			—			191
		218,522		(141,798		)	(50,242		)	26,482
	Intangible assets not yet subject to amortization:
	IPR&D (see Note 2)	12,400		—			—			12,400
	Total purchased intangible assets	$	230,922	$	(141,798	)	$	(50,242	)	$	38,882
		As of December 29, 2012
		Gross		Accumulated			Accumulated			Net
		Amount		Amortization			Impairment			Amount
		(in thousands)
	Intangible assets subject to amortization:
	Patents and trademarks	$	43,475	$	(33,463	)	$	—		$	10,012
	Core technology	37,180		(21,388		)	(12,642		)	3,150
	Developed technology	127,940		(76,379		)	(37,600		)	13,961
	Pre-existing license agreement	2,300		(465		)	—			1,835
	Customer based relationships and other	6,578		(2,220		)	—			4,358
	Foreign currency translation impact	255		—			—			255
	Total purchased intangible assets	$	217,728	$	(133,915	)	$	(50,242	)	$	33,571
	Purchased identifiable intangible assets are amortized on either a straight-line or accelerated method based on the expected pattern of future benefits related to those respective intangible assets. Subsequent to the impairment of the core and developed technology associated with our PVAD and IVAD intangible assets which was recorded in the fourth quarter of 2012, we changed our method of amortization for this intangible asset from the straight-line method to an accelerated method to more closely reflect the expected pattern of benefits associated with the remaining carrying amount of this intangible asset.
	Amortization expense related to identifiable intangible assets (subject to amortization) was $2.6 million and $7.7 million for the three and nine months ended September 28, 2013, respectively, and $2.7 million and $8.2 million for the three and nine months ended September 29, 2012, respectively.
	Estimated amortization expenses for the next five fiscal years and all years thereafter, excluding intangible assets not yet subject to amortization are as follows:
		(in thousands)
	Fiscal year:
	Remainder of 2013	$	2,870
	2014	6,993
	2015	4,790
	2016	3,461
	2017	2,560
	Thereafter	5,808
	Total	$	26,482

Credit_Facility

Credit Facility	9 Months Ended
	Sep. 28, 2013
Credit Facility	'
Credit Facility	'
	Note 7. Credit Facility
	On December 19, 2011, we signed an unsecured revolving credit facility agreement that provides for up to $50 million revolving credit that will expire on December 19, 2016. The interest rate charged on the amounts borrowed is LIBOR plus a margin (ranging from 0.75% to 1.25%). The credit agreement contains financial covenants. We were in compliance with all such covenants as of September 28, 2013. The credit agreement permits us to use the facility for working capital and general corporate purposes. As of September 28, 2013, there were no borrowings under this credit facility.

ShareBased_Compensation

Share-Based Compensation	9 Months Ended
	Sep. 28, 2013
Share-Based Compensation	'
Share-Based Compensation	'
	Note 8. Share-Based Compensation
	Our Board of Directors approved the 2006 Incentive Stock Plan (the “2006 Plan”). The 2006 Plan was last amended in May 2012. Participation in the 2006 Plan is limited to employees, directors, and consultants. Shares reserved for future issuance under the 2006 Plan may be used for grants of stock options (“options”), restricted stock units (“RSUs”), and other types of awards. Options granted under the 2006 Plan are either incentive or nonqualified stock options and generally become exercisable in annual installments over a period of four years from the date of grant and expire generally ten years from the grant date. RSUs generally vest in annual installments over a four-year period.
	The Board of Directors authorizes the granting of options, RSUs and other type of awards to employees and consultants. The exercise prices of the options shall not be less than the fair market value of common stock on the date of grant. The fair value of RSUs granted is determined based on the number of RSUs granted and the quoted price of our common stock on the date of grant. As of September 28, 2013, approximately 3.3 million shares remained available for issuance under the 2006 Plan.
	Additionally, we sponsor an Employee Stock Purchase Plan (the “ESPP”) in which eligible employees may contribute up to 15% of their base compensation to purchase shares of common stock at a price equal to 85% of the lower of the market value of the stock at the beginning or end of each six-month offer period. As of September 28, 2013, approximately 340,000 shares remained available for issuance under the ESPP. Share-based compensation consists of the following:
		Three Months Ended						Nine Months Ended
		September 28,			September 29,			September 28,		September 29,
		2013			2012			2013		2012
		(in thousands)
	Cost of product sales	$	586		$	550		$	1,773	$	1,525
	Selling, general and administrative expenses	4,373			3,442			12,681		9,829
	Research and development	1,896			1,576			5,772		4,679
	Total share-based compensation expense before taxes	6,855			5,568			20,226		16,033
	Tax benefit for share-based compensation expense	2,605			2,104			7,675		6,064
	Total share-based compensation (net of taxes)	$	4,250		$	3,464		$	12,551	$	9,969
	Share-based compensation costs of $0.6 million and $0.2 million were capitalized to inventory as of September 28, 2013 and December 29, 2012.
	Stock Options
	The fair value of each option is estimated at the date of grant using the Black-Scholes option pricing model with the following assumptions:
		Three Months Ended				Nine Months Ended
		September 28,		September 29,		September 28,		September 29,
		2013		2012		2013		2012
	Risk free interest rate (weighted average)	2	%	1.19	%	1.38	%	1.4	%
	Expected volatility	40	%	40	%	37	%	43	%
	Expected option term (years)	4.932		4.93 to 5.95		4.92 to 5.70		4.82 to 5.84
	Dividends	None		None		None		None
	Stock option activity is summarized as follows:
		Number of		Weighted			Weighted Average
		Options		Average Exercise			Remaining Contract
		(in thousands)		Price Per Share			Life (years)
	Outstanding options as of December 29, 2012	2,498		$	25.98		6.3
	Granted	578		35.58
	Exercised	(320	)	20.75
	Forfeited or expired	(65	)	32.54
	Outstanding options as of September 28, 2013	2,691		$	28.5		6.5
	Outstanding options exercisable as of September 28, 2013	1,361		$	23.99		4.5
	Outstanding options vested as of September 28, 2013 and expected to vest	2,615		$	28.35		6.4
	As of September 28, 2013, there was $8.6 million of unrecognized compensation expense, net of estimated forfeitures, related to stock options, which expense we expect to recognize over a weighted average period of 1.51 years.
	Restricted Stock Units
	Restricted stock unit activity is summarized as follows:
		Number of		Weighted Average			Weighted Average
		Units		Grant Date Fair			Remaining Contract
		(in thousands)		Value			Life (in years)
	Outstanding units as of December 29, 2012	1,462		$	31.52		1.4
	Granted	626		35.14
	Released	(509	)	30.2
	Forfeited or expired	(72	)	32.91
	Outstanding units as of September 28, 2013	1,507		$	33.41		1.5
	As of September 28, 2013, there was $37.5 million of unrecognized compensation expense, net of estimated forfeitures, related to restricted stock units, which amount we expect to recognize over 2.44 years.
	Employee Stock Purchase Plan
	The estimated subscription date fair value of the offering under the ESPP for each of the nine months ended September 28, 2013 and September 29, 2012, was approximately $0.5 million using the Black-Scholes option pricing model and the following assumptions:
		Nine Months Ended
		September 28,		September 29,
		2013		2012
	Risk-free-interest rate	0.08	%	0.15	%
	Expected volatility	30	%	40	%
	Expected option life	0.50 years		0.50 years
	Dividends	None		None
	As of September 28, 2013, there was approximately $0.1 million of unrecognized compensation expense related to ESPP subscriptions that began on May 1, 2013, which amount we expect to recognize through October 31, 2013.

Common_and_Preferred_Stock

Common and Preferred Stock	9 Months Ended
	Sep. 28, 2013
Common and Preferred Stock	'
Common and Preferred Stock	'
	Note 9. Common and Preferred Stock
	On November 26, 2012, our Board of Directors authorized the repurchase of up to $150 million of shares of the Company’s common stock (“November 2012 program”). As part of the authorization, the Company entered into an Accelerated Share Repurchase (“2012 ASR”) agreement with an investment bank, under which we agreed to repurchase an aggregate of $75.0 million of our common stock. Under the 2012 ASR program, we paid $75.0 million and received an initial delivery of approximately 1.5 million shares, which represented 75% of the 2012 ASR program’s estimated value at inception. At the maturity of the program in the first quarter of 2013, an additional 0.6 million shares were delivered to the Company. The total value of the shares repurchased by the Company under the 2012 ASR program was based on a per share price of $36.00, representing the volume-weighted average price of our common stock during the repurchase period, less an agreed upon discount.
	During the third quarter of 2013, the Company entered into an Accelerated Share Repurchase (“2013 ASR”) agreement with an investment bank, under which we agreed to repurchase an aggregate of $40.0 million of our common stock. Under the 2013 ASR program, we paid $40.0 million and received an initial delivery of 820,120 shares, which represented 75% of the 2013 ASR program’s estimated value at inception. Shares representing the remaining 25% of the 2013 ASR Program’s value will be delivered at maturity date of the program, which can be up to 1.5 months from the inception of the program, with the final number of shares to be repurchased based on the volume-weighted average price (VWAP) of our common stock during the repurchase period, less an agreed upon discount and adjusted for the initial share delivery. Under the terms of the 2013 ASR, at settlement, we could either receive additional shares from the counterparty or be required to deliver additional shares or cash, at our option, to the counterparty. The total number of shares ultimately repurchased will not be known until the calculation period ends and a final settlement occurs, which we expect will be in the fourth quarter of 2013. As of September 28, 2013, $35.0 million was available for repurchases of shares of our common stock under the November 2012 program.
	The 2013 ASR program was accounted for as two separate transactions: (i) as shares of common stock acquired in a share repurchase transaction and (ii) as a forward contract indexed to our own common stock. The initial delivery of shares resulted in an immediate reduction of the outstanding shares used to calculate the weighted-average common shares outstanding for basic and diluted net earnings per share from the effective date of the ASR Program. We have determined that the forward contract indexed to our common stock met all of the applicable criteria for equity classification. We are incorporated in California, and as California law does not recognize treasury stock, the shares repurchased decreased the common shares outstanding. We recorded the $30.1 million of shares repurchased by reducing the additional-paid-in capital balance based on the average-issuance price per share of all shares outstanding prior to the repurchase with the excess allocated to retained earnings. Based on this allocation, additional-paid-in capital decreased by $9.8 million and retained earnings decreased by $20.3 million in the condensed consolidated statement of shareholders’ equity. The remaining balance of $9.9 million was recorded as an equity forward contract, which is included in Additional Paid-in Capital in the accompanying condensed consolidated balance sheet as of September 28, 2013.
	Shares of our common stock purchased that were not part of our publicly announced repurchase programs represent the surrender value of shares of restricted stock units withheld in order to satisfy tax withholding obligations upon vesting. The shares purchased do not reduce the dollar value that may yet be purchased under our publicly announced repurchase programs. The aggregate value of shares purchased during the three and nine months ended September 28, 2013 was approximately $0.2 million and $7.1 million, respectively. The aggregate value of shares purchased during the three and nine months ended September 29, 2012 was approximately $0.1 million and $5.0 million, respectively.

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 28, 2013
Income Taxes	'
Income Taxes	'
	Note 10. Income Taxes
	On January 2, 2013, the U.S. President signed into law The American Taxpayer Relief Act of 2012. This Act extends the research tax credit for two years to December 31, 2013. The extension of the research tax credit is retroactive and includes amounts paid or incurred after December 29, 2011. As a result of the enactment after the Company’s 2012 year end, we recognized, in the first quarter of 2013, a benefit of approximately $1.3 million for qualifying amounts incurred in 2012.
	Our effective income tax rates for the three months ended September 28, 2013 and September 29, 2012 were 17.5% and 27.2%, respectively.  Our effective income tax rates for the nine months ended September 28, 2013 and September 29, 2012 were 25.3% and 30.8%, respectively. The decrease is primarily attributable to the recognition of Federal tax benefits due to the expiration of statutes of limitations in the third quarter of 2013 and the 2012 federal research tax credits, which we recognized in the first quarter of 2013 (in the period of enactment), as well as the 2013 federal research tax credits.
	During the next 12 months, it is reasonably possible that audit resolutions and the expiration of statutes of limitations could potentially reduce our unrecognized tax benefits by up to $1.6 million. However, this amount may change because we continue to have ongoing negotiations with various taxing authorities throughout the year.

Segment_and_Geographic_Informa

Segment and Geographic Information	9 Months Ended
	Sep. 28, 2013
Segment and Geographic Information	'
Segment and Geographic Information	'
	Note 11. Segment and Geographic Information
	The accounting standard for segment reporting establishes standards for reporting information about operating segments in annual financial statements and requires selected information for those segments to be presented in interim financial reports of public business enterprises. It also establishes standards for related disclosures about products and services, geographic areas and major customers. Based on an evaluation of our business, including the operations acquired in the DuraHeart II transaction, we determined that we have one operating segment, Cardiovascular group. This segment is organized and operates to develop and manufacture mechanical circulatory products to support the cardiovascular systems of humans.
	Product sales attributed to a country or region include product sales to hospitals, physicians and distributors and are based on final destinations where the products are sold. No individual customer or individual country outside of the U.S. accounted for more than 10% of product sales during the three and nine months ended September 28, 2013 or during the three and nine months ended September 29, 2012.
		Three Months Ended				Nine Months Ended
		September 28,		September 29,		September 28,		September 29,
		2013		2012		2013		2012
		(in thousands)
	Product sales by geographic location:
	Domestic	$	99,608	$	97,515	$	290,643	$	298,507
	International	26,836		20,253		84,005		64,689
	Total	$	126,444	$	117,768	$	374,648	$	363,196
		Three Months Ended				Nine Months Ended
		September 28,		September 29,		September 28,		September 29,
		2013		2012		2013		2012
		(in thousands)
	Product sales by product line:
	HeartMate	$	112,837	$	105,845	$	331,404	$	323,778
	CentriMag	10,448		7,536		32,327		24,239
	Thoratec	2,592		3,832		9,108		13,396
	Other	567		555		1,809		1,783
	Total	$	126,444	$	117,768	$	374,648	$	363,196
		Three Months Ended				Nine Months Ended
		September 28,		September 29,		September 28,		September 29,
		2013		2012		2013		2012
		(in thousands)
	Product sales by category:
	Pump	$	87,108	$	85,024	$	264,867	$	263,317
	Non-Pump	38,769		32,189		107,972		98,096
	Other	567		555		1,809		1,783
	Total	$	126,444	$	117,768	$	374,648	$	363,196

Net_Income_Per_Share

Net Income Per Share	9 Months Ended
	Sep. 28, 2013
Net Income Per Share	'
Net Income Per Share	'
	12. Net Income Per Share
	Restricted stock awards (“RSA”) previously granted under the 2006 Plan are subject to repurchase and have non-forfeitable rights to receive dividends as common stock and therefore are considered participating securities. All outstanding RSAs were fully vested at the end of 2012. Under the two-class method, basic and diluted net income per common share are determined by calculating net income per share for common stock and participating securities based on participation rights in undistributed earnings. Dilutive net income per common share also considers the dilutive effect of in-the-money stock options and restricted stock units, calculated using the treasury stock method. Under the treasury stock method, the amount of assumed proceeds from unexercised stock options and restricted stock units includes the amount of unrecognized compensation cost attributable to future services, assumed proceeds from the exercise of the options, and the incremental income tax benefit or liability that would be recorded in additional-paid-in capital when the award becomes deductible.
	Basic and diluted net income per common share attributable to common shareholders under the two-class method was calculated as follows:
		Three Months Ended					Nine Months Ended
		September 28,			September 29,		September 28,		September 29,
		2013			2012		2013		2012
		(in thousands, except per share data)
	Basic net income per common share calculation
	Net income	$	18,904		$	24,255	$	60,263	$	70,549
	Net income allocated to participating securities	—			—		—		(20		)
	Net income attributable to common shareholders	$	18,904		$	24,255	$	60,263	$	70,529
	Weighted average number of common shares used to compute basic net income per common share	57,427			58,762		57,447		58,645
	Basic net income per common share	$	0.33		$	0.41	$	1.05	$	1.2
		Three Months Ended					Nine Months Ended
		September 28,			September 29,		September 28,		September 29,
		2013			2012		2013		2012
		(in thousands, except per share data)
	Diluted net income per common share calculation
	Net income	$	18,904		$	24,255	$	60,263	$	70,549
	Net income allocated to participating securities	—			—		—		(20		)
	Net income attributable to common shareholders	$	18,904		$	24,255	$	60,263	$	70,529
	Weighted average number of common shares used to compute basic net income per common share attributable to common shares	57,427			58,762		57,447		58,645
	Dilutive effect of stock-based compensation plans	807			907		953		964
	Weighted average number of common shares used to compute diluted net income per common share	58,234			59,669		58,400		59,609
	Diluted net income per common share	$	0.32		$	0.41	$	1.03	$	1.18
	Potential common share equivalents excluded where the inclusion would be anti-dilutive are as follows:
		Three Months Ended				Nine Months Ended
		September 28,		September 29,		September 28,	September 29,
		2013		2012		2013	2012
		(in thousands)
	Options to purchase shares not included in the computation of diluted income per share because their inclusion would be anti-dilutive	642		640		1,008	509

Operations_and_Significant_Acc1

Operations and Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 28, 2013
Operations and Significant Accounting Policies	'
Basis of Presentation	'
	Basis of Presentation
	The interim unaudited condensed consolidated financial statements of Thoratec Corporation (“we,” “our,” “us,” or the “Company”) have been prepared and presented in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and the rules and regulations of the Securities and Exchange Commission (“SEC”), without audit, and reflect all adjustments necessary (consisting only of normal recurring adjustments) to present fairly our financial position, results of operations and cash flows as of and for the periods presented. Certain information and footnote disclosures normally included in our annual financial statements, prepared in accordance with GAAP, have been condensed or omitted. The accompanying financial statements should be read in conjunction with our fiscal 2012 consolidated financial statements, and the accompanying notes thereto, filed with the SEC in our 2012 Annual Report on Form 10-K for the fiscal year ended December 29, 2012 (the “2012 Annual Report”). The operating results for any interim period are not necessarily indicative of the results that may be expected for any future period.
	The preparation of our unaudited condensed consolidated financial statements necessarily requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities on the unaudited condensed consolidated balance sheet dates and the reported amounts of revenues and expenses for the periods presented.  The actual amounts could differ from those estimated amounts.

Acquisition_of_DuraHeart_II_Ta

Acquisition of DuraHeart II (Tables)	9 Months Ended
	Sep. 28, 2013
Acquisition of DuraHeart II	'
Schedule of total purchase price consideration	'
	Total purchase price consideration was as follows (in thousands):
	Cash paid at the acquisition closing date (June 30, 2013)	$	13,000
	Estimated fair value of contingent consideration	18,800
	Total estimated purchase price	$	31,800
Summary of preliminary purchase price allocation as of the acquisition date	'
	Preliminary Purchase Price Allocation as of the acquisition date is summarized as follows (in thousands):
	Property, plant and equipment	$	8,900
	Identifiable intangible assets:
	Favorable lease contract	600
	In-process research and development	12,400
	Goodwill	9,900
	Total estimated purchase price consideration	31,800
	Less: Contingent consideration	18,800
	Cash paid at the acquisition closing	$	13,000
Schedule of pro forma financial information	'
		Nine Months Ended		Nine Months Ended
		September 28, 2013		September 29, 2012
		(in thousands)
	Product sales	$	374,648	$	363,196
	Income before taxes	65,922		77,691
	Net income	49,242		53,764

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 28, 2013
Fair Value Measurements	'
Financial assets and financial liabilities measured at fair value on a recurring basis	'
		Total Fair			Quoted			Significant			Significant
		Value			Prices in			Other			Unobservable
					Active			Observable			Inputs
					Markets			Inputs			(Level 3)
					(Level 1)			(Level 2)
		(in thousands)
	As of September 28, 2013:
	Cash equivalents:
	Money market funds	$	78,501		$	78,501		$	—		$	—
	Commercial paper	10,599			—			10,599			—
	Municipal bonds	793			—			793			—
	Short-term investments:
	Municipal bonds	144,997			—			144,997			—
	Variable demand notes	7,700			—			7,700			—
	Corporate bonds	5,512			—			5,512			—
	Commercial paper	10,997			—			10,997			—
	Certificate of deposit	2,000						2,000			—
	Auction rate securities	4,800			—			—			4,800
	Prepaid expenses and other assets:
	Foreign exchange contracts	369			—			369			—
	Long-term investments:
	Auction rate securities	4,160			—			—			4,160
	Other long-term assets:
	Investments included in our deferred compensation plan	1,838			—			1,838			—
	Marketable equity securities	5,115			5,115			—			—
	Other accrued liabilities:
	Foreign exchange contracts	1,408			—			1,408			—
	Contingent consideration (current and long-term portions)	$	40,545		$	—		$	—		$	40,545
		Total Fair			Quoted			Significant			Significant
		Value			Prices in			Other			Unobservable
					Active			Observable			Inputs
					Markets			Inputs			(Level 3)
					(Level 1)			(Level 2)
		(in thousands)
	As of December 29, 2012:
	Cash equivalents:
	Money market funds	$	59,230		$	59,230		$	—		$	—
	Commercial paper	4,998			—			4,998			—
	Municipal bonds	3,045			—			3,045			—
	Corporate bonds	380			—			380			—
	Short-term investments:
	Municipal bonds	107,533			—			107,533			—
	Variable demand notes	21,330			—			21,330			—
	Corporate bonds	12,258			—			12,258			—
	Commercial paper	5,299			—			5,299			—
	Certificate of deposit	2,006			—			2,006			—
	Prepaid expenses and other assets:
	Foreign exchange contracts	16			—			16			—
	Long-term investments:
	Auction rate securities	10,607			—			—			10,607
	Other long-term assets:
	Investments included in our deferred compensation plan	1,731			—			1,731			—
	Marketable equity securities	2,602			2,602			—			—
	Other accrued liabilities:
	Foreign exchange contracts	380			—			380			—
	Contingent consideration (current and long-term portions)	$	22,052		$	—		$	—		$	22,052
Summary of aggregate market value, amortized cost basis and gross unrealized gains and losses for available-for-sale investments	'
		Amortized			Gross			Gross			Fair
		Cost			Unrealized			Unrealized			Value
					Gains			Losses
		(in thousands)
	As of September 28, 2013:
	Short-term investments:
	Municipal bonds	$	144,848		$	172		$	(23	)	$	144,997
	Variable demand notes	7,700			—			—			7,700
	Corporate bonds	5,508			6			(2		)	5,512
	Commercial paper	10,996			—			—			10,996
	Certificate of deposit	2,000			—			—			2,000
	Auction rate securities	4,800			—			—			4,800
	Total short-term investments	$	175,852		$	178		$	(25	)	$	176,005
	Long-term investments:
	Auction rate securities	$	4,900		$	—		$	(740	)	$	4,160
	Other long-term assets:
	Marketable equity securities	2,996			2,119			—			5,115
	Total long-term	$	7,896		$	2,119		$	(740	)	$	9,275
	As of December 29, 2012:
	Short-term investments:
	Municipal bonds	$	107,416		$	136		$	(19	)	$	107,533
	Variable demand notes	21,330			—			—			21,330
	Corporate bonds	12,244			17			(3		)	12,258
	Commercial paper	5,298			1			—			5,299
	Certificate of deposit	2,000			6			—			2,006
	Total short-term investments	$	148,288		$	160		$	(22	)	$	148,426
	Long-term investments:
	Auction rate securities	$	11,900		$	—		$	(1,293	)	$	10,607
	Other long-term assets:
	Marketable equity securities (A)	2,996			—			(394		)	2,602
	Total long-term	$	14,896		$	—		$	(1,687	)	$	13,209
	(A)       As of December 29, 2012, our available-for-sale equity securities have been in a continuous loss position for less than 12 months.
Schedule of aggregate value of deferred compensation plan assets	'
		September 28,			December 29,
		2013			2012
		(in thousands)
	Deferred compensation plan	$	5,216		$	4,225
Schedule of amortized cost and fair value of available-for-sale debt investments, by contractual maturity	'
	The amortized cost and fair value of available-for-sale debt investments, by contractual maturity, were as follows as of September 28, 2013:
		Amortized			Fair
		Cost			Value
		(in thousands)
	Maturing within 1 year	$	139,211		$	139,302
	Maturing after 1 year through 5 years	36,641			36,703
	Short-term available-for-sale investments	175,852			176,005
	Maturing after 5 years	4,900			4,160
		$	180,752		$	180,165
Schedule of roll forward of fair value, as determined by Level 3 inputs, of auction rate securities and contingent consideration (current and long-term portions)	'
		Auction
		Rate
		Securities
		(in thousands)
	Balance as of December 29, 2012	$	10,607
	Settlements at par	(2,200		)
	Unrealized gain on auction rate securities, included in other comprehensive income	553
	Balance as of September 28, 2013	8,960
	Less: Reported within short-term available-for-sale investments	(4,800		)
	Total long-term available-for-sale investments	$	4,160
		Levitronix Medical			DuraHeart II			Total
		Acquisition			Acquisition			Contingent
								Consideration
		(in thousands)
	Balance as of December 29, 2012	$	22,052		$	—		$	22,052
	Additions (See Note 2)	—			18,800			18,800
	Payments	(4,220		)	—			(4,220		)
	Change in fair value	3,647			266			3,913
	Balance as of September 28, 2013	$	21,479		$	19,066		$	40,545
Schedule of quantitative information for Level 3 Fair Value Measurements	'
		Fair Value at			Valuation Methodology		Significant Unobservable Input		Weighted Average
		September 28,							(range, if applicable)
		2013
		(in thousands)
	Auction rate securities	$	8,960		Discounted cash flow		Discount rate		1.40%
							Market credit spread		3.15%
							Liquidity factor		0.00%
	Levitronix Medical Contingent consideration	$	21,479		Multiple outcome discounted cash flow		Annual Revenue		$ 42.3 million ($29.6 million to $48.2 million)
							Discount rate		1.04% (0.8% to 1.39%)
							Probability of occurrence		20% (10% to 50%)
	DuraHeart II Contingent consideration	$	19,066		Multiple outcome discounted cash flow		Milestone dates		2016 to 2029
							Discount rate		5.3% to 20.0%
							Probability of occurrence		1% to 50%

Foreign_Exchange_Instruments_T

Foreign Exchange Instruments (Tables)	9 Months Ended
	Sep. 28, 2013
Foreign Exchange Instruments	'
Schedule of notional amount of foreign currency contracts, which do not qualify for hedge accounting	'
		September 28,			December 29,
		2013			2012
	Forward contracts:
	Euro (sell)	€	17.8 million		€	13.9 million
	British Pound Sterling (sell)	£	1.3 million		£	1.8 million
	U.S. Dollar (sell)	$	17.0 million		$	5.3 million
	U.S. Dollar (buy)	$	59.0 million		$	73.5 million
Schedule of derivative instruments measured at gross fair value reported on the condensed consolidated balance sheets	'
		As of September 28, 2013						As of December 29, 2012
		Prepaid expenses			Other accrued			Prepaid expenses			Other accrued
		and other assets			liabilities			and other assets			liabilities
		(in thousands)
	Derivatives not designated as hedging instruments (forward contracts)	$	369		$	1,408		$	16		$	380
Schedule of effect of derivative instruments not designated as hedging instruments and foreign currency transactions gains and losses	'
		Three Months Ended						Nine Months Ended
		September 28,			September 29,			September 28,			September 29,
		2013			2012			2013			2012
		(in thousands)
	Foreign currency exchange loss on foreign contracts	$	(1,953	)	$	(2,462	)	$	(649	)	$	(130	)
	Foreign currency transactions gain	2,122			2,617			1,114			308

Balance_Sheet_Information_Tabl

Balance Sheet Information (Tables)	9 Months Ended
	Sep. 28, 2013
Balance Sheet Information	'
Schedule of Inventories	'
		September 28,			December 29,
		2013			2012
		(in thousands)
	Finished goods	$	24,446		$	15,087
	Work in process	14,639			11,020
	Raw materials	27,079			20,993
	Total	$	66,164		$	47,100
Schedule of Property, Plant and Equipment, net	'
		September 28,			December 29,
		2013			2012
		(in thousands)
	Land, building and improvements	$	20,594		$	20,543
	Equipment and capitalized software	59,421			46,290
	Furniture and leasehold improvements	22,394			20,933
	Total	102,409			87,766
	Less Accumulated depreciation	(47,702		)	(41,874		)
	Total	$	54,707		$	45,892
Changes in the warranty provision	'
		September 28,			September 29,
		2013			2012
		(in thousands)
	Balance, beginning of the period	$	2,212		$	2,452
	Additions	2,982			1,132
	Settlements	(1,666		)	(1,308		)
	Balance, end of the period	$	3,528		$	2,276
Foreign Currency, changes in accumulated other comprehensive loss	'
		Foreign currency			Unrealized			Total
		items (A)			gain (loss) on
					available-for-sale
					securities (A)
		(in thousands)
	Balance as of December 29, 2012	$	(13,928	)	$	(1,141	)	$	(15,069	)
	Other comprehensive loss before reclassification	(460		)	1,851			1,391
	Amounts reclassified from accumulated other comprehensive loss	—			—			—
	Net current period other comprehensive loss	(460		)	1,851			1,391
	Balance as of September 28, 2013	$	(14,388	)	$	710		$	(13,678	)
	(A)       All amounts are net of tax.

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets, net (Tables)	9 Months Ended
	Sep. 28, 2013
Goodwill and Intangible Assets, net	'
Schedule of changes in carrying amount of goodwill	'
	The carrying amount of goodwill and the changes in the balances for the nine months ended September 28, 2013 were as follows (in thousands):
	Balance as of December 29, 2012	$	194,182
	Goodwill addition (See Note 2)	9,900
	Foreign currency translation impact	211
	Balance as of September 28, 2013	$	204,293
Schedule of intangible assets on the condensed consolidated balance sheets	'
		As of September 28, 2013
		Gross		Accumulated			Accumulated			Net
		Amount		Amortization			Impairment			Amount
		(in thousands)
	Intangible assets subject to amortization:
	Patents and trademarks	$	43,532	$	(34,478	)	$	—		$	9,054
	Core technology	37,180		(22,587		)	(12,642		)	1,951
	Developed technology	128,073		(80,427		)	(37,600		)	10,046
	Pre-existing license agreement	2,300		(712		)	—			1,588
	Customer based relationships and other	7,246		(3,594		)	—			3,652
	Foreign currency translation impact	191		—			—			191
		218,522		(141,798		)	(50,242		)	26,482
	Intangible assets not yet subject to amortization:
	IPR&D (see Note 2)	12,400		—			—			12,400
	Total purchased intangible assets	$	230,922	$	(141,798	)	$	(50,242	)	$	38,882
		As of December 29, 2012
		Gross		Accumulated			Accumulated			Net
		Amount		Amortization			Impairment			Amount
		(in thousands)
	Intangible assets subject to amortization:
	Patents and trademarks	$	43,475	$	(33,463	)	$	—		$	10,012
	Core technology	37,180		(21,388		)	(12,642		)	3,150
	Developed technology	127,940		(76,379		)	(37,600		)	13,961
	Pre-existing license agreement	2,300		(465		)	—			1,835
	Customer based relationships and other	6,578		(2,220		)	—			4,358
	Foreign currency translation impact	255		—			—			255
	Total purchased intangible assets	$	217,728	$	(133,915	)	$	(50,242	)	$	33,571
Estimated amortization expenses for the next five fiscal years and all years thereafter, excluding intangible assets not yet subject to amortization	'
		(in thousands)
	Fiscal year:
	Remainder of 2013	$	2,870
	2014	6,993
	2015	4,790
	2016	3,461
	2017	2,560
	Thereafter	5,808
	Total	$	26,482

ShareBased_Compensation_Tables

Share-Based Compensation (Tables)	9 Months Ended
	Sep. 28, 2013
Share-Based Compensation	'
Schedule of share-based compensation	'
		Three Months Ended						Nine Months Ended
		September 28,			September 29,			September 28,		September 29,
		2013			2012			2013		2012
		(in thousands)
	Cost of product sales	$	586		$	550		$	1,773	$	1,525
	Selling, general and administrative expenses	4,373			3,442			12,681		9,829
	Research and development	1,896			1,576			5,772		4,679
	Total share-based compensation expense before taxes	6,855			5,568			20,226		16,033
	Tax benefit for share-based compensation expense	2,605			2,104			7,675		6,064
	Total share-based compensation (net of taxes)	$	4,250		$	3,464		$	12,551	$	9,969
Schedule of assumptions used to estimate the grant date fair value of options	'
		Three Months Ended				Nine Months Ended
		September 28,		September 29,		September 28,		September 29,
		2013		2012		2013		2012
	Risk free interest rate (weighted average)	2	%	1.19	%	1.38	%	1.4	%
	Expected volatility	40	%	40	%	37	%	43	%
	Expected option term (years)	4.932		4.93 to 5.95		4.92 to 5.70		4.82 to 5.84
	Dividends	None		None		None		None
Summary of stock option activity	'
		Number of		Weighted			Weighted Average
		Options		Average Exercise			Remaining Contract
		(in thousands)		Price Per Share			Life (years)
	Outstanding options as of December 29, 2012	2,498		$	25.98		6.3
	Granted	578		35.58
	Exercised	(320	)	20.75
	Forfeited or expired	(65	)	32.54
	Outstanding options as of September 28, 2013	2,691		$	28.5		6.5
	Outstanding options exercisable as of September 28, 2013	1,361		$	23.99		4.5
	Outstanding options vested as of September 28, 2013 and expected to vest	2,615		$	28.35		6.4
Summary of restricted stock unit activity	'
		Number of		Weighted Average			Weighted Average
		Units		Grant Date Fair			Remaining Contract
		(in thousands)		Value			Life (in years)
	Outstanding units as of December 29, 2012	1,462		$	31.52		1.4
	Granted	626		35.14
	Released	(509	)	30.2
	Forfeited or expired	(72	)	32.91
	Outstanding units as of September 28, 2013	1,507		$	33.41		1.5
Schedule of assumptions used to estimate subscription date fair value of the ESPP offerings	'
		Nine Months Ended
		September 28,		September 29,
		2013		2012
	Risk-free-interest rate	0.08	%	0.15	%
	Expected volatility	30	%	40	%
	Expected option life	0.50 years		0.50 years
	Dividends	None		None

Segment_and_Geographic_Informa1

Segment and Geographic Information (Tables)	9 Months Ended
	Sep. 28, 2013
Segment and Geographic Information	'
Schedule of geographic composition of the entity's product sales from continuing operations	'
		Three Months Ended				Nine Months Ended
		September 28,		September 29,		September 28,		September 29,
		2013		2012		2013		2012
		(in thousands)
	Product sales by geographic location:
	Domestic	$	99,608	$	97,515	$	290,643	$	298,507
	International	26,836		20,253		84,005		64,689
	Total	$	126,444	$	117,768	$	374,648	$	363,196
Schedule of product sales from continuing operations by product line	'
		Three Months Ended				Nine Months Ended
		September 28,		September 29,		September 28,		September 29,
		2013		2012		2013		2012
		(in thousands)
	Product sales by product line:
	HeartMate	$	112,837	$	105,845	$	331,404	$	323,778
	CentriMag	10,448		7,536		32,327		24,239
	Thoratec	2,592		3,832		9,108		13,396
	Other	567		555		1,809		1,783
	Total	$	126,444	$	117,768	$	374,648	$	363,196
Schedule of product sales by category	'
		Three Months Ended				Nine Months Ended
		September 28,		September 29,		September 28,		September 29,
		2013		2012		2013		2012
		(in thousands)
	Product sales by category:
	Pump	$	87,108	$	85,024	$	264,867	$	263,317
	Non-Pump	38,769		32,189		107,972		98,096
	Other	567		555		1,809		1,783
	Total	$	126,444	$	117,768	$	374,648	$	363,196

Net_Income_Per_Share_Tables

Net Income Per Share (Tables)	9 Months Ended
	Sep. 28, 2013
Net Income Per Share	'
Schedule of Basic and diluted net income per common share attributable to common shareholders under the two-class method	'
		Three Months Ended					Nine Months Ended
		September 28,			September 29,		September 28,		September 29,
		2013			2012		2013		2012
		(in thousands, except per share data)
	Basic net income per common share calculation
	Net income	$	18,904		$	24,255	$	60,263	$	70,549
	Net income allocated to participating securities	—			—		—		(20		)
	Net income attributable to common shareholders	$	18,904		$	24,255	$	60,263	$	70,529
	Weighted average number of common shares used to compute basic net income per common share	57,427			58,762		57,447		58,645
	Basic net income per common share	$	0.33		$	0.41	$	1.05	$	1.2
		Three Months Ended					Nine Months Ended
		September 28,			September 29,		September 28,		September 29,
		2013			2012		2013		2012
		(in thousands, except per share data)
	Diluted net income per common share calculation
	Net income	$	18,904		$	24,255	$	60,263	$	70,549
	Net income allocated to participating securities	—			—		—		(20		)
	Net income attributable to common shareholders	$	18,904		$	24,255	$	60,263	$	70,529
	Weighted average number of common shares used to compute basic net income per common share attributable to common shares	57,427			58,762		57,447		58,645
	Dilutive effect of stock-based compensation plans	807			907		953		964
	Weighted average number of common shares used to compute diluted net income per common share	58,234			59,669		58,400		59,609
	Diluted net income per common share	$	0.32		$	0.41	$	1.03	$	1.18
Schedule of potential common share equivalents excluded where the inclusion would be anti-dilutive	'
		Three Months Ended				Nine Months Ended
		September 28,		September 29,		September 28,	September 29,
		2013		2012		2013	2012
		(in thousands)
	Options to purchase shares not included in the computation of diluted income per share because their inclusion would be anti-dilutive	642		640		1,008	509

Acquisition_of_DuraHeart_II_De

Acquisition of DuraHeart II (Details) (USD $)

9 Months Ended

9 Months Ended

0 Months Ended

0 Months Ended

3 Months Ended

0 Months Ended

3 Months Ended

Sep. 28, 2013

Sep. 29, 2012

Dec. 29, 2012

Sep. 28, 2013

Jul. 02, 2013

Jul. 02, 2013

Jul. 02, 2013

Jul. 02, 2013

Sep. 28, 2013

Jul. 02, 2013

Jul. 02, 2013

Jul. 02, 2013

Sep. 28, 2013

Jul. 02, 2013

DuraHeart II Acquisition

DuraHeart II Acquisition

DuraHeart II Acquisition

DuraHeart II Acquisition

DuraHeart II Acquisition

DuraHeart II Acquisition

DuraHeart II Acquisition

DuraHeart II Acquisition

DuraHeart II Acquisition

DuraHeart II Acquisition

DuraHeart II Acquisition

In-process research and development

Favorable lease contract

Contingent consideration payable upon reaching regulatory milestone

Contingent consideration payable upon reaching regulatory milestone

Contingent consideration payable upon CE Mark approval

Contingent consideration payable upon FDA approval

Contingent consideration payable upon reaching commercial sales milestone

Contingent consideration payable upon reaching commercial sales milestone

Maximum

Acquisition of DuraHeart II

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash paid

'

'

'

'

$13,000,000

'

'

'

'

'

'

'

'

'

Potential future milestone payments

'

'

'

'

'

'

'

'

'

5,500,000

10,500,000

27,500,000

'

43,500,000

Acquisition-related costs

'

'

'

2,000,000

'

'

'

'

'

'

'

'

'

'

Goodwill

'

'

'

'

9,900,000

'

'

'

'

'

'

'

'

'

Goodwill recorded as a result of business acquisition that is deductible for income tax purposes

'

'

'

'

9,900,000

'

'

'

'

'

'

'

'

'

Revenue

'

'

'

0

'

'

'

'

'

'

'

'

'

'

Net loss

'

'

'

-1,500,000

'

'

'

'

'

'

'

'

'

'

Fair value of non-current contingent consideration liability

33,138,000

'

17,832,000

'

18,800,000

'

'

'

'

'

'

'

'

'

Total purchase price consideration

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash paid

'

'

'

'

13,000,000

'

'

'

'

'

'

'

'

'

Estimated fair value of contingent consideration

'

'

'

'

18,800,000

'

'

'

'

'

'

'

'

'

Total estimated purchase price

'

'

'

'

31,800,000

'

'

'

'

'

'

'

'

'

Discount rate (as a percent)

'

'

'

'

'

22.50%

'

5.30%

'

'

'

20.00%

'

'

Increase in fair value of contingent consideration

-3,913,000

'

'

'

'

'

'

'

100,000

'

'

'

200,000

'

Summary of purchase price allocation

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Property, plant and equipment

'

'

'

'

8,900,000

'

'

'

'

'

'

'

'

'

Finite-lived identifiable intangible assets

'

'

'

'

'

'

600,000

'

'

'

'

'

'

'

Indefinite-lived identifiable intangible assets

'

'

'

'

'

12,400,000

'

'

'

'

'

'

'

'

Goodwill

'

'

'

'

9,900,000

'

'

'

'

'

'

'

'

'

Total estimated purchase price consideration

'

'

'

'

31,800,000

'

'

'

'

'

'

'

'

'

Less: Contingent consideration

'

'

'

'

18,800,000

'

'

'

'

'

'

'

'

'

Cash paid at the acquisition closing

'

'

'

'

13,000,000

'

'

'

'

'

'

'

'

'

Weighted average cost of capital (as a percent)

'

'

'

'

'

22.50%

'

5.30%

'

'

'

20.00%

'

'

Acquisition related transaction costs

2,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Acquisition related transaction costs excluded from 2013 pro forma results

2,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Pro forma financial information

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Product sales

374,648,000

363,196,000

'

'

'

'

'

'

'

'

'

'

'

'

Income before taxes

65,922,000

77,691,000

'

'

'

'

'

'

'

'

'

'

'

'

Net income

$49,242,000

$53,764,000

'

'

'

'

'

'

'

'

'

'

'

'

Fair_Value_Measurements_Detail

Fair Value Measurements (Details) (USD $)

9 Months Ended

In Thousands, unless otherwise specified

Sep. 28, 2013

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Commercial Paper

Commercial Paper

Municipal bonds

Municipal bonds

Variable demand notes

Variable demand notes

Corporate bonds

Corporate bonds

Long-term investments - auction rate securities

Long-term investments - auction rate securities

Certificate of deposit

Certificate of deposit

Marketable equity securities

Marketable equity securities

Short-term investments - auction rate securities

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Recurring basis

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Total fair value

Quoted prices in active markets for identical assets (Level 1)

Quoted prices in active markets for identical assets (Level 1)

Quoted prices in active markets for identical assets (Level 1)

Quoted prices in active markets for identical assets (Level 1)

Significant other observable inputs (Level 2)

Significant other observable inputs (Level 2)

Significant other observable inputs (Level 2)

Significant other observable inputs (Level 2)

Significant other observable inputs (Level 2)

Significant other observable inputs (Level 2)

Significant other observable inputs (Level 2)

Significant other observable inputs (Level 2)

Significant other observable inputs (Level 2)

Significant other observable inputs (Level 2)

Significant other observable inputs (Level 2)

Significant other observable inputs (Level 2)

Significant unobservable inputs (Level 3)

Significant unobservable inputs (Level 3)

Significant unobservable inputs (Level 3)

Significant unobservable inputs (Level 3)

Significant unobservable inputs (Level 3)

Money market funds

Money market funds

Commercial Paper

Commercial Paper

Municipal bonds

Municipal bonds

Variable demand notes

Variable demand notes

Corporate bonds

Corporate bonds

Long-term investments - auction rate securities

Long-term investments - auction rate securities

Certificate of deposit

Certificate of deposit

Marketable equity securities

Marketable equity securities

Short-term investments - auction rate securities

Money market funds

Money market funds

Marketable equity securities

Marketable equity securities

Commercial Paper

Commercial Paper

Municipal bonds

Municipal bonds

Variable demand notes

Variable demand notes

Corporate bonds

Corporate bonds

Certificate of deposit

Certificate of deposit

Long-term investments - auction rate securities

Long-term investments - auction rate securities

Short-term investments - auction rate securities

Hierarchy of financial assets and financial liabilities measured at fair value on a recurring basis:

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash equivalents

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$78,501

$59,230

$10,599

$4,998

$793

$3,045

'

'

'

$380

'

'

'

'

'

'

'

$78,501

$59,230

'

'

'

'

$10,599

$4,998

$793

$3,045

'

'

'

$380

'

'

'

'

'

'

'

Investments

'

10,996

5,299

144,997

107,533

7,700

21,330

5,512

12,258

4,160

10,607

2,000

2,006

5,115

2,602

4,800

'

'

'

'

10,997

5,299

144,997

107,533

7,700

21,330

5,512

12,258

4,160

10,607

2,000

2,006

5,115

2,602

4,800

'

'

5,115

2,602

'

'

10,997

5,299

144,997

107,533

7,700

21,330

5,512

12,258

2,000

2,006

'

'

4,160

10,607

4,800

Prepaid expenses and other assets - Foreign exchange contracts

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

369

16

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

369

16

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Other long term assets: Carrying value of investments included in our deferred compensation plan

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,838

1,731

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,838

1,731

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Liabilities:

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Other accrued liabilities - Foreign exchange contracts

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,408

380

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,408

380

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Contingent consideration (current and long-term portions)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$40,545

$22,052

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$40,545

$22,052

'

'

'

Cash flow model discount period

'5 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Fair_Value_Measurements_Detail1

Fair Value Measurements (Details 2) (USD $)	9 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Dec. 29, 2012
Available-for-sale investments, Other Disclosures	'	'	'
Cumulative unrealized loss related to the temporary impairment, net of tax	$710,000	'	($1,141,000)
Other long-term assets - investments - deferred compensation plan	'	'	'
Deferred compensation plan	5,216,000	'	4,225,000
Unrealized gain before tax from the change in the value of the deferred compensation plan	400,000	300,000	'
Contractual maturities of available-for-sale investments, Amortized Cost	'	'	'
Total Amortized Cost	180,752,000	'	'
Contractual maturities of available-for-sale investments, Fair Value	'	'	'
Total Fair Value	180,165,000	'	'
Short-term investments	'	'	'
Available-for-sale investments by major security type:	'	'	'
Amortized Cost	175,852,000	'	148,288,000
Gross Unrealized Gains	178,000	'	160,000
Gross Unrealized Losses	-25,000	'	-22,000
Fair Value	176,005,000	'	148,426,000
Contractual maturities of available-for-sale investments, Amortized Cost	'	'	'
Maturing within 1 year	139,211,000	'	'
Maturing after 1 year through 5 years	36,641,000	'	'
Total Amortized Cost	175,852,000	'	'
Maturing after 5 years	4,900,000	'	'
Contractual maturities of available-for-sale investments, Fair Value	'	'	'
Maturing within 1 year	139,302,000	'	'
Maturing after 1 year through 5 years	36,703,000	'	'
Total Fair Value	176,005,000	'	'
Maturing after 5 years	4,160,000	'	'
Municipal bonds	'	'	'
Available-for-sale investments by major security type:	'	'	'
Amortized Cost	144,848,000	'	107,416,000
Gross Unrealized Gains	172,000	'	136,000
Gross Unrealized Losses	-23,000	'	-19,000
Fair Value	144,997,000	'	107,533,000
Variable demand notes	'	'	'
Available-for-sale investments by major security type:	'	'	'
Amortized Cost	7,700,000	'	21,330,000
Fair Value	7,700,000	'	21,330,000
Corporate bonds	'	'	'
Available-for-sale investments by major security type:	'	'	'
Amortized Cost	5,508,000	'	12,244,000
Gross Unrealized Gains	6,000	'	17,000
Gross Unrealized Losses	-2,000	'	-3,000
Fair Value	5,512,000	'	12,258,000
Commercial Paper	'	'	'
Available-for-sale investments by major security type:	'	'	'
Amortized Cost	10,996,000	'	5,298,000
Gross Unrealized Gains	'	'	1,000
Fair Value	10,996,000	'	5,299,000
Certificate of deposit	'	'	'
Available-for-sale investments by major security type:	'	'	'
Amortized Cost	2,000,000	'	2,000,000
Gross Unrealized Gains	'	'	6,000
Fair Value	2,000,000	'	2,006,000
Short-term investments - auction rate securities	'	'	'
Available-for-sale investments by major security type:	'	'	'
Amortized Cost	4,800,000	'	'
Fair Value	4,800,000	'	'
Available-for-sale investments, Other Disclosures	'	'	'
Liquidated of auction rate securities at par value	4,800,000	'	'
Long-term investments	'	'	'
Available-for-sale investments by major security type:	'	'	'
Amortized Cost	7,896,000	'	14,896,000
Gross Unrealized Gains	2,119,000	'	'
Gross Unrealized Losses	-740,000	'	-1,687,000
Fair Value	9,275,000	'	13,209,000
Long-term investments - auction rate securities	'	'	'
Available-for-sale investments by major security type:	'	'	'
Amortized Cost	4,900,000	'	11,900,000
Gross Unrealized Losses	-740,000	'	-1,293,000
Fair Value	4,160,000	'	10,607,000
Available-for-sale investments, Other Disclosures	'	'	'
Cumulative unrealized loss related to the auction rate securities, before tax	-700,000	'	'
Cumulative unrealized loss related to the temporary impairment, net of tax	400,000	'	'
Percentage of the principal and accrued interest to be received from the issuer, not probable to be less than	100.00%	'	'
Percent of impairment charged to other comprehensive income (loss)	100.00%	'	'
Liquidated of auction rate securities at par value	2,200,000	'	'
Maximum final maturity of the underlying notes to auction rate securities	'30 years	'	'
Long-term investments - auction rate securities | Maximum	'	'	'
Available-for-sale investments, Other Disclosures	'	'	'
Auction rate securities, rate setting interval	'35 days	'	'
Long-term investments - auction rate securities | Minimum	'	'	'
Available-for-sale investments, Other Disclosures	'	'	'
Auction rate securities, rate setting interval	'7 days	'	'
Marketable equity securities	'	'	'
Available-for-sale investments by major security type:	'	'	'
Amortized Cost	2,996,000	'	2,996,000
Gross Unrealized Gains	2,119,000	'	'
Gross Unrealized Losses	'	'	-394,000
Fair Value	$5,115,000	'	$2,602,000

Fair_Value_Measurements_Detail2

Fair Value Measurements (Details 3) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013
Levitronix Medical	'
Changes in liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3)	'
Balance, beginning of the fiscal year	$22,052
Payments	-4,220
Change in fair value	3,647
Balance, end of the fiscal year	21,479
DuraHeart II Acquisition	'
Changes in liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3)	'
Additions	18,800
Change in fair value	266
Balance, end of the fiscal year	19,066
Auction rate securities	'
Reconciliation of the beginning and ending balances for the assets measured as fair value using significant unobservable inputs (Level 3):	'
Balance, beginning of the fiscal year	10,607
Settlements at par	-2,200
Unrealized gain on auction rate securities, included in other comprehensive income	553
Balance, end of the fiscal year	8,960
Auction rate securities | Short-term investments	'
Reconciliation of the beginning and ending balances for the assets measured as fair value using significant unobservable inputs (Level 3):	'
Balance, end of the fiscal year	-4,800
Auction rate securities | Long-term investments	'
Reconciliation of the beginning and ending balances for the assets measured as fair value using significant unobservable inputs (Level 3):	'
Balance, end of the fiscal year	4,160
Contingent Consideration	'
Changes in liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3)	'
Balance, beginning of the fiscal year	22,052
Additions	18,800
Payments	-4,220
Change in fair value	3,913
Balance, end of the fiscal year	$40,545

Fair_Value_Measurements_Detail3

Fair Value Measurements (Details 4) (Auction rate securities, Discounted cash flow, USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013
Quantitative information for Level 3 Fair Value Measurements Assets	'
Fair value Assets	8,960
Weighted Average	'
Quantitative information for Level 3 Fair Value Measurements Assets	'
Discount rate (as a percent)	1.40%
Market credit spread (as a percent)	3.15%
Liquidity factor (as a percent)	0.00%

Fair_Value_Measurements_Detail4

Fair Value Measurements (Details 5) (USD $)	3 Months Ended	9 Months Ended
	Sep. 28, 2013	Sep. 28, 2013	Sep. 29, 2012
Quantitative information for Level 3 Fair Value Measurements Liabilities	'	'	'
Adjustments to contingent consideration	$3,600,000	$300,000	$0
Impairment charge related to property, plant, and equipment	'	1,961,000	'
Multiple outcome discounted cash flow | Levitronix Medical	'	'	'
Quantitative information for Level 3 Fair Value Measurements Liabilities	'	'	'
Fair value Liabilities	21,479,000	21,479,000	'
Multiple outcome discounted cash flow | DuraHeart II Acquisition	'	'	'
Quantitative information for Level 3 Fair Value Measurements Liabilities	'	'	'
Fair value Liabilities	19,066,000	19,066,000	'
Multiple outcome discounted cash flow | Minimum | Levitronix Medical	'	'	'
Quantitative information for Level 3 Fair Value Measurements Liabilities	'	'	'
Annual Revenue	29,600,000	29,600,000	'
Discount rate (as a percent)	'	0.80%	'
Probability of occurrence (as a percent)	'	10.00%	'
Multiple outcome discounted cash flow | Minimum | DuraHeart II Acquisition	'	'	'
Quantitative information for Level 3 Fair Value Measurements Liabilities	'	'	'
Discount rate (as a percent)	'	5.30%	'
Probability of occurrence (as a percent)	'	1.00%	'
Multiple outcome discounted cash flow | Maximum | Levitronix Medical	'	'	'
Quantitative information for Level 3 Fair Value Measurements Liabilities	'	'	'
Annual Revenue	48,200,000	48,200,000	'
Discount rate (as a percent)	'	1.39%	'
Probability of occurrence (as a percent)	'	50.00%	'
Multiple outcome discounted cash flow | Maximum | DuraHeart II Acquisition	'	'	'
Quantitative information for Level 3 Fair Value Measurements Liabilities	'	'	'
Discount rate (as a percent)	'	20.00%	'
Probability of occurrence (as a percent)	'	50.00%	'
Multiple outcome discounted cash flow | Weighted Average | Levitronix Medical	'	'	'
Quantitative information for Level 3 Fair Value Measurements Liabilities	'	'	'
Annual Revenue	$42,300,000	$42,300,000	'
Discount rate (as a percent)	'	1.04%	'
Probability of occurrence (as a percent)	'	20.00%	'

Foreign_Exchange_Instruments_D

Foreign Exchange Instruments (Details)

3 Months Ended

9 Months Ended

9 Months Ended

Sep. 28, 2013

Sep. 29, 2012

Sep. 28, 2013

Sep. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

Sep. 28, 2013

Dec. 29, 2012

USD ($)

USD ($)

USD ($)

USD ($)

Prepaid expenses and other assets

Prepaid expenses and other assets

Other accrued liabilities

Other accrued liabilities

Not Designated

Not Designated

Not Designated

Not Designated

Not Designated

Not Designated

Not Designated

Not Designated

Not Designated

USD ($)

USD ($)

USD ($)

USD ($)

Maximum

Euro (sell)

Euro (sell)

British Pound Sterling (sell)

British Pound Sterling (sell)

U.S. Dollar (sell)

U.S. Dollar (sell)

U.S. Dollar (buy) 1

U.S. Dollar (buy) 1

EUR (€)

EUR (€)

GBP (£)

GBP (£)

USD ($)

USD ($)

USD ($)

USD ($)

Foreign currency forward exchange details

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Approximate period forward contracts

'

'

'

'

'

'

'

'

'6 months

'

'

'

'

'

'

'

'

Gross notional amounts for outstanding derivatives

'

'

'

'

'

'

'

'

'

€ 17,800,000

€ 13,900,000

£ 1,300,000

£ 1,800,000

$17,000,000

$5,300,000

$59,000,000

$73,500,000

Gross fair value of Derivatives not designated as hedging instruments (forward contracts)

'

'

'

'

369,000

16,000

1,408,000

380,000

'

'

'

'

'

'

'

'

'

Foreign currency exchange loss on foreign contracts

-1,953,000

-2,462,000

-649,000

-130,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Foreign currency transactions gain

$2,122,000

$2,617,000

$1,114,000

$308,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance_Sheet_Information_Deta

Balance Sheet Information (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012	Dec. 29, 2012
Inventories	'	'	'	'	'
Finished goods	$24,446,000	'	$24,446,000	'	$15,087,000
Work-in-process	14,639,000	'	14,639,000	'	11,020,000
Raw materials	27,079,000	'	27,079,000	'	20,993,000
Total inventories	66,164,000	'	66,164,000	'	47,100,000
Property, plant and equipment, net	'	'	'	'	'
Property, plant and equipment, gross	102,409,000	'	102,409,000	'	87,766,000
Less Accumulated depreciation	-47,702,000	'	-47,702,000	'	-41,874,000
Total Property, plant and equipment, net	54,707,000	'	54,707,000	'	45,892,000
Depreciation expense	2,000,000	2,200,000	6,100,000	6,400,000	'
Changes in the warranty provision	'	'	'	'	'
Balance, beginning of the period	'	'	2,212,000	2,452,000	'
Additions	'	'	2,982,000	1,132,000	'
Settlements	'	'	-1,666,000	-1,308,000	'
Balance, end of the period	3,528,000	2,276,000	3,528,000	2,276,000	'
Foreign currency, changes in accumulated other comprehensive income	'	'	'	'	'
Balance at the beginning of the period	'	'	-13,928,000	'	'
Other comprehensive income before reclassification	'	'	-460,000	'	'
Net current-period other comprehensive income	'	'	-460,000	'	'
Balance at the end of the period	-14,388,000	'	-14,388,000	'	'
Unrealized gain (loss) on available-for-sale securities, changes in accumulated other comprehensive income	'	'	'	'	'
Balance at the beginning of the period	'	'	-1,141,000	'	'
Other comprehensive income before reclassification	'	'	1,851,000	'	'
Net current-period other comprehensive income	'	'	1,851,000	'	'
Balance at the end of the period	710,000	'	710,000	'	'
Changes in accumulated other comprehensive loss	'	'	'	'	'
Balance at beginning of period	'	'	-15,069,000	'	'
Other comprehensive loss before reclassification	'	'	1,391,000	'	'
Net current period other comprehensive loss	'	'	1,391,000	'	'
Balance at the end of the period	-13,678,000	'	-13,678,000	'	'
Land, building and improvements	'	'	'	'	'
Property, plant and equipment, net	'	'	'	'	'
Property, plant and equipment, gross	20,594,000	'	20,594,000	'	20,543,000
Equipment and capitalized software	'	'	'	'	'
Property, plant and equipment, net	'	'	'	'	'
Property, plant and equipment, gross	59,421,000	'	59,421,000	'	46,290,000
Furniture and leasehold improvements	'	'	'	'	'
Property, plant and equipment, net	'	'	'	'	'
Property, plant and equipment, gross	$22,394,000	'	$22,394,000	'	$20,933,000

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets, net (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012	Dec. 29, 2012
Changes in carrying amount of goodwill	'	'	'	'	'
Balance, beginning of the period	'	'	$194,182,000	'	'
Goodwill additions	'	'	9,900,000	'	'
Foreign currency translation impact	'	'	211,000	'	'
Balance, end of period	204,293,000	'	204,293,000	'	194,182,000
Intangible assets subject to amortization:	'	'	'	'	'
Foreign currency translation adjustments, gross	191,000	'	191,000	'	255,000
Foreign currency translation adjustments, net	191,000	'	191,000	'	255,000
Gross Carrying Amount	218,522,000	'	218,522,000	'	'
Accumulated Amortization	-141,798,000	'	-141,798,000	'	-133,915,000
Impairment charge	'	'	-50,242,000	'	-50,242,000
Total intangible assets subject to amortization	26,482,000	'	26,482,000	'	'
Intangible assets not yet subject to amortization:	'	'	'	'	'
Total purchased intangible assets, gross	230,922,000	'	230,922,000	'	217,728,000
Total purchased intangible assets, net	38,882,000	'	38,882,000	'	33,571,000
Amortization expense related to identifiable intangible assets (subject to amortization)	2,600,000	2,700,000	7,700,000	8,200,000	'
Estimated amortization expenses for the next five fiscal years and all years thereafter, excluding intangible assets not yet subject to amortization	'	'	'	'	'
Remainder of 2013	2,870,000	'	2,870,000	'	'
2014	6,993,000	'	6,993,000	'	'
2015	4,790,000	'	4,790,000	'	'
2016	3,461,000	'	3,461,000	'	'
2017	2,560,000	'	2,560,000	'	'
Thereafter	5,808,000	'	5,808,000	'	'
Total intangible assets subject to amortization	26,482,000	'	26,482,000	'	'
IPR&D	'	'	'	'	'
Intangible assets not yet subject to amortization:	'	'	'	'	'
Total intangible assets not yet subject to amortization	12,400,000	'	12,400,000	'	'
Patents and trademarks	'	'	'	'	'
Intangible assets subject to amortization:	'	'	'	'	'
Gross carrying amount before adjustments	43,532,000	'	43,532,000	'	43,475,000
Accumulated amortization before adjustments	-34,478,000	'	-34,478,000	'	-33,463,000
Net carrying amount before adjustments	9,054,000	'	9,054,000	'	10,012,000
Core technology	'	'	'	'	'
Intangible assets subject to amortization:	'	'	'	'	'
Gross carrying amount before adjustments	37,180,000	'	37,180,000	'	37,180,000
Accumulated amortization before adjustments	-22,587,000	'	-22,587,000	'	-21,388,000
Accumulated impairment before adjustments	-12,642,000	'	-12,642,000	'	-12,642,000
Net carrying amount before adjustments	1,951,000	'	1,951,000	'	3,150,000
Developed technology	'	'	'	'	'
Intangible assets subject to amortization:	'	'	'	'	'
Gross carrying amount before adjustments	128,073,000	'	128,073,000	'	127,940,000
Accumulated amortization before adjustments	-80,427,000	'	-80,427,000	'	-76,379,000
Accumulated impairment before adjustments	-37,600,000	'	-37,600,000	'	-37,600,000
Net carrying amount before adjustments	10,046,000	'	10,046,000	'	13,961,000
Pre-existing license agreements	'	'	'	'	'
Intangible assets subject to amortization:	'	'	'	'	'
Gross carrying amount before adjustments	2,300,000	'	2,300,000	'	2,300,000
Accumulated amortization before adjustments	-712,000	'	-712,000	'	-465,000
Net carrying amount before adjustments	1,588,000	'	1,588,000	'	1,835,000
Customer based relationships and other	'	'	'	'	'
Intangible assets subject to amortization:	'	'	'	'	'
Gross carrying amount before adjustments	7,246,000	'	7,246,000	'	6,578,000
Accumulated amortization before adjustments	-3,594,000	'	-3,594,000	'	-2,220,000
Net carrying amount before adjustments	$3,652,000	'	$3,652,000	'	$4,358,000

Credit_Facility_Details

Credit Facility (Details) (Credit Facility, USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 28, 2013	Dec. 19, 2011
Credit facility	'	'
Maximum borrowing capacity	'	$50
Reference rate for variable rate (as a percent)	'LIBOR plus	'
Borrowings under credit facility	$0	'
Minimum	'	'
Credit facility	'	'
Margin rate (as a percent)	0.75%	'
Maximum	'	'
Credit facility	'	'
Margin rate (as a percent)	1.25%	'

ShareBased_Compensation_Detail

Share-Based Compensation (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012	Dec. 29, 2012
Share-based compensation	'	'	'	'	'
Remaining shares available for issuance	3,300,000	'	3,300,000	'	'
Share-based compensation cost	$6,855,000	$5,568,000	$20,226,000	$16,033,000	'
Tax benefit for share-based compensation expense	2,605,000	2,104,000	7,675,000	6,064,000	'
Total share-based compensation (net of taxes)	4,250,000	3,464,000	12,551,000	9,969,000	'
Share-based compensation costs capitalized to inventory	'	'	600,000	'	200,000
Stock options	'	'	'	'	'
Share-based compensation	'	'	'	'	'
General vesting period	'	'	'4 years	'	'
Expiration period	'	'	'10 years	'	'
Method and assumptions on valuation of stock options	'	'	'	'	'
Risk-free interest rate (weighted average) (as a percent)	2.00%	1.19%	1.38%	1.40%	'
Expected volatility (as a percent)	40.00%	40.00%	37.00%	43.00%	'
Expected option term	'4 years 11 months 6 days	'	'	'	'
Dividends (as a percent)	0.00%	0.00%	0.00%	0.00%	'
Number of options	'	'	'	'	'
Outstanding options at the beginning of the period (in shares)	'	'	2,498,000	'	'
Granted (in shares)	'	'	578,000	'	'
Exercised (in shares)	'	'	-320,000	'	'
Forfeited or expired (in shares)	'	'	-65,000	'	'
Outstanding options at the end of the period (in shares)	2,691,000	'	2,691,000	'	2,498,000
Outstanding options exercisable at the end of the period (in shares)	1,361,000	'	1,361,000	'	'
Outstanding options vested at the end of the period and expected to vest (in shares)	2,615,000	'	2,615,000	'	'
Stock options, Weighted-Average Exercise Price Per Share	'	'	'	'	'
Outstanding options at the beginning of the period (in dollars per share)	'	'	$25.98	'	'
Granted (in dollars per share)	'	'	$35.58	'	'
Exercised (in dollars per share)	'	'	$20.75	'	'
Forfeited or expired (in dollars per share)	'	'	$32.54	'	'
Outstanding options at the end of the period (in dollars per share)	$28.50	'	$28.50	'	$25.98
Outstanding options exercisable at the end of the period (in dollars per share)	$23.99	'	$23.99	'	'
Outstanding options vested at the end of the period and expected to vest (in dollars per share)	$28.35	'	$28.35	'	'
Weighted Average Remaining Contract Life (years)	'	'	'	'	'
Outstanding options at the beginning of the period	'	'	'6 years 6 months	'	'6 years 2 months 12 days
Outstanding options at the end of the period	'	'	'6 years 6 months	'	'6 years 2 months 12 days
Outstanding options exercisable at the end of the period	'	'	'4 years 6 months	'	'
Outstanding options vested at the end of the period and expected to vest	'	'	'6 years 4 months 24 days	'	'
Unrecognized compensation expenses, net of estimated forfeitures	8,600,000	'	8,600,000	'	'
Weighted average period for unrecognized compensation cost expected to be recognized	'	'	'1 year 6 months 4 days	'	'
Stock options | Minimum	'	'	'	'	'
Method and assumptions on valuation of stock options	'	'	'	'	'
Expected option term	'	'4 years 11 months 5 days	'4 years 11 months 1 day	'4 years 9 months 25 days	'
Stock options | Maximum	'	'	'	'	'
Method and assumptions on valuation of stock options	'	'	'	'	'
Expected option term	'	'5 years 11 months 12 days	'5 years 8 months 12 days	'5 years 10 months 2 days	'
Restricted stock	'	'	'	'	'
Share-based compensation	'	'	'	'	'
General vesting period	'	'	'4 years	'	'
Restricted stock units	'	'	'	'	'
Share-based compensation	'	'	'	'	'
General vesting period	'	'	'4 years	'	'
Weighted Average Remaining Contract Life (years)	'	'	'	'	'
Unrecognized compensation expenses, net of estimated forfeitures	37,500,000	'	37,500,000	'	'
Weighted average period for unrecognized compensation cost expected to be recognized	'	'	'2 years 5 months 8 days	'	'
Employee Stock Purchase Plan (ESPP)	'	'	'	'	'
Share-based compensation	'	'	'	'	'
Remaining shares available for issuance	340,000	'	340,000	'	'
Maximum percentage of base compensation that can be contributed by the eligible employee	'	'	15.00%	'	'
Purchase price of common stock as a percentage of the market value on the offering date or the purchase date	'	'	85.00%	'	'
The period during which eligible employees can purchase shares	'	'	'6 months	'	'
Method and assumptions on valuation of stock options	'	'	'	'	'
Risk-free interest rate (weighted average) (as a percent)	'	'	0.08%	0.15%	'
Expected volatility (as a percent)	'	'	30.00%	40.00%	'
Expected option term	'	'	'6 months	'6 months	'
Dividends (as a percent)	'	'	0.00%	0.00%	'
Weighted Average Remaining Contract Life (years)	'	'	'	'	'
Unrecognized compensation expenses, net of estimated forfeitures	100,000	'	100,000	'	'
Cost of product sales	'	'	'	'	'
Share-based compensation	'	'	'	'	'
Share-based compensation cost	586,000	550,000	1,773,000	1,525,000	'
Selling, general and administrative expenses	'	'	'	'	'
Share-based compensation	'	'	'	'	'
Share-based compensation cost	4,373,000	3,442,000	12,681,000	9,829,000	'
Research and development	'	'	'	'	'
Share-based compensation	'	'	'	'	'
Share-based compensation cost	$1,896,000	$1,576,000	$5,772,000	$4,679,000	'

ShareBased_Compensation_Detail1

Share-Based Compensation (Details 2) (USD $)	9 Months Ended	12 Months Ended	9 Months Ended
In Millions, except Share data in Thousands, unless otherwise specified	Sep. 28, 2013	Dec. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
	Restricted stock units	Restricted stock units	Employee Stock Purchase Plan	Employee Stock Purchase Plan
Number of shares and units	'	'	'	'
Outstanding unvested restricted stock at the beginning of the period (in shares)	1,462	'	'	'
Granted (in shares)	626	'	'	'
Released (in shares)	-509	'	'	'
Forfeited or expired (in shares)	-72	'	'	'
Outstanding unvested restricted stock at the end of the period (in shares)	1,507	1,462	'	'
Weighted average grant date fair value	'	'	'	'
Outstanding unvested restricted stock at the beginning of the year (in dollars per share)	$31.52	'	'	'
Granted (in dollars per share)	$35.14	'	'	'
Released (in dollars per share)	$30.20	'	'	'
Forfeited or expired (in dollars per share)	$32.91	'	'	'
Outstanding unvested restricted stock at the end of the year (in dollars per share)	$33.41	$31.52	'	'
Weighted Average Remaining Contract Life (in years)	'	'	'	'
Weighted Average Remaining Contract Life	'1 year 6 months	'1 year 4 months 24 days	'	'
Weighted Average Remaining Contract Life	'1 year 6 months	'1 year 4 months 24 days	'	'
Unrecognized compensation expenses, net of estimated forfeitures	$37.50	'	$0.10	'
Weighted average period for unrecognized compensation cost expected to be recognized	'2 years 5 months 8 days	'	'	'
Stock compensation plan	'	'	'	'
Estimated subscription date fair value	'	'	$0.50	$0.50
Method and assumptions on valuation of ESPP	'	'	'	'
Risk-free interest rate (as a percent)	'	'	0.08%	0.15%
Expected volatility (as a percent)	'	'	30.00%	40.00%
Expected option life	'	'	'6 months	'6 months
Dividends (as a percent)	'	'	0.00%	0.00%

Common_and_Preferred_Stock_Det

Common and Preferred Stock (Details) (USD $)	0 Months Ended	3 Months Ended			9 Months Ended
In Millions, except Share data, unless otherwise specified	Nov. 26, 2012	Sep. 28, 2013	Mar. 30, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Common and Preferred Stock	'	'	'	'	'	'
Maximum amount for repurchase of common stock	$75	'	'	'	'	'
Aggregate amount of common stock agreed to be repurchased	75	'	'	'	'	'
Number of shares repurchased	1,500,000	'	'	'	'	'
Percentage of the ASR Program's value received	75.00%	'	'	'	'	'
Number of additional shares delivered at maturity date of the program	'	'	600,000	'	'	'
Common stock repurchase average price per share (in dollars per share)	'	'	'	'	$36	'
Amount utilized to repurchase common stock	'	0.2	'	0.1	7.1	5
November 2012 program	'	'	'	'	'	'
Common and Preferred Stock	'	'	'	'	'	'
Maximum amount for repurchase of common stock	150	'	'	'	35	'
2013 ASR	'	'	'	'	'	'
Common and Preferred Stock	'	'	'	'	'	'
Maximum amount for repurchase of common stock	'	40	'	'	'	'
Aggregate amount of common stock agreed to be repurchased	'	40	'	'	'	'
Number of shares repurchased	'	820,120	'	'	'	'
Percentage of the ASR Program's value received	'	75.00%	'	'	'	'
Percentage of the ASR Program's value deliverable at maturity date of the program	'	25.00%	'	'	'	'
Maximum maturity period of the ASR Program	'	'1 month 15 days	'	'	'	'
Number of separate transactions	'	2	'	'	'	'
Repurchases of shares of our common stock under stock repurchase programs	'	'	'	'	30.1	'
Additional-paid-in capital	'	'	'	'	9.8	'
Retained earnings	'	'	'	'	20.3	'
Equity forward contract	'	'	'	'	$9.90	'

Income_Taxes_Details

Income Taxes (Details) (USD $)	3 Months Ended		9 Months Ended		0 Months Ended
In Millions, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012	Jan. 02, 2013
					Research and development
Tax credit carryovers	'	'	'	'	'
Extension period for tax credits due to enactment of law	'	'	'	'	'2 years
Tax benefits expected to be recognized due to enactment of law	'	'	'	'	$1.30
Reconciliation of income taxes at the U.S. federal statutory income tax rate to income before taxes (as a percent)	'	'	'	'	'
Effective income tax rates (as a percent)	17.50%	27.20%	25.30%	30.80%	'
Reasonably possible potential reduction in unrecognized tax benefits over the next 12 months	$1.60	'	$1.60	'	'

Segment_and_Geographic_Informa2

Segment and Geographic Information (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
			segment
Segment and Geographic Information	'	'	'	'
Number of operating segment	'	'	1	'
Segment Information	'	'	'	'
Total product sales from continuing operations	$126,444	$117,768	$374,648	$363,196
Domestic	'	'	'	'
Segment Information	'	'	'	'
Total product sales from continuing operations	99,608	97,515	290,643	298,507
International	'	'	'	'
Segment Information	'	'	'	'
Total product sales from continuing operations	26,836	20,253	84,005	64,689
Heart Mate	'	'	'	'
Segment Information	'	'	'	'
Total product sales from continuing operations	112,837	105,845	331,404	323,778
CentriMag	'	'	'	'
Segment Information	'	'	'	'
Total product sales from continuing operations	10,448	7,536	32,327	24,239
Thoratec	'	'	'	'
Segment Information	'	'	'	'
Total product sales from continuing operations	2,592	3,832	9,108	13,396
Other	'	'	'	'
Segment Information	'	'	'	'
Total product sales from continuing operations	567	555	1,809	1,783
Pump	'	'	'	'
Segment Information	'	'	'	'
Total product sales from continuing operations	87,108	85,024	264,867	263,317
Non-Pump	'	'	'	'
Segment Information	'	'	'	'
Total product sales from continuing operations	38,769	32,189	107,972	98,096
Other	'	'	'	'
Segment Information	'	'	'	'
Total product sales from continuing operations	$567	$555	$1,809	$1,783

Net_Income_Per_Share_Details

Net Income Per Share (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Basic net income per common share calculation	'	'	'	'
Net income	$18,904	$24,255	$60,263	$70,549
Net income allocated to participating securities	'	'	'	-20
Net income attributable to common shareholders	$18,904	$24,255	$60,263	$70,529
Weighted average number of common shares used to compute basic net income per common share	57,427	58,762	57,447	58,645
Basic net income per common share (in dollars per share)	$0.33	$0.41	$1.05	$1.20

Net_Income_Per_Share_Details_2

Net Income Per Share (Details 2) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Diluted net income per common share calculation	'	'	'	'
Net income	$18,904	$24,255	$60,263	$70,549
Net income allocated to participating securities	'	'	'	-20
Net income attributable to common shareholders	$18,904	$24,255	$60,263	$70,529
Weighted average number of common shares used to compute basic net income per common share attributable to common shares	57,427	58,762	57,447	58,645
Dilutive effect of share-based compensation plans (in shares)	807	907	953	964
Weighted average number of common shares used to compute diluted net income per common share	58,234	59,669	58,400	59,609
Diluted net income per common share (in dollars per share)	$0.32	$0.41	$1.03	$1.18
Options	'	'	'	'
Potential common share equivalents excluded	'	'	'	'
Options to purchase shares not included in the computation of diluted income per share because their inclusion would be anti-dilutive	642	640	1,008	509