Novanta (NOVT) 10-Q 7 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Apr. 03, 2015	Apr. 29, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	3-Apr-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Trading Symbol	GSIG
Entity Registrant Name	GSI GROUP INC
Entity Central Index Key	1076930
Current Fiscal Year End Date	-19
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		34,406,281

CONSOLIDATED_BALANCE_SHEETS

CONSOLIDATED BALANCE SHEETS (USD $)	Apr. 03, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Current Assets
Cash and cash equivalents	$47,542	$51,146
Accounts receivable, net of allowance of $221 and $282, respectively	53,360	51,494
Inventories	60,682	62,943
Income taxes receivable	5,178	5,906
Deferred tax assets	5,589	5,971
Prepaid expenses and other current assets	7,099	5,236
Assets held for sale	13,582	631
Total current assets	193,032	183,327
Property, plant and equipment, net	37,590	40,088
Deferred tax assets	2,879	2,912
Other assets	12,984	14,604
Intangible assets, net	70,284	67,242
Goodwill	98,299	90,746
Total assets	415,068	398,919
Current Liabilities
Current portion of long-term debt	7,500	7,500
Accounts payable	27,126	25,592
Income taxes payable	1,055	1,189
Deferred tax liabilities	198	208
Accrued expenses and other current liabilities	21,524	19,401
Liabilities held for sale	2,954	324
Total current liabilities	60,357	54,214
Long-term debt	115,625	107,500
Deferred tax liabilities	2,273	35
Income taxes payable	6,838	7,097
Other liabilities	18,695	18,819
Total liabilities	203,788	187,665
Commitments and Contingencies (Note 13)
Stockholders’ Equity:
Common shares, no par value; Authorized shares: unlimited; Issued and outstanding: 34,406 and 34,219, respectively	423,856	423,856
Additional paid-in capital	28,947	28,590
Accumulated deficit	-221,719	-225,165
Accumulated other comprehensive loss	-20,233	-16,456
Total GSI Group Inc. stockholders’ equity	210,851	210,825
Noncontrolling interest	429	429
Total stockholders’ equity	211,280	211,254
Total liabilities and stockholders’ equity	$415,068	$398,919

CONSOLIDATED_BALANCE_SHEETS_Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Apr. 03, 2015	Dec. 31, 2014
In Thousands, except Per Share data, unless otherwise specified
Statement Of Financial Position [Abstract]
Accounts receivable, allowance	$221	$282
Common shares, no par value	$0	$0
Common shares, Issued	34,406	34,219
Common shares, outstanding	34,406	34,219

CONSOLIDATED_STATEMENTS_OF_OPE

CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Apr. 03, 2015	Mar. 28, 2014
Income Statement [Abstract]
Sales	$94,614	$79,133
Cost of sales	54,608	47,028
Gross profit	40,006	32,105
Operating expenses:
Research and development and engineering	8,215	5,857
Selling, general and administrative	22,068	19,618
Amortization of purchased intangible assets	1,889	1,744
Restructuring, acquisition and divestiture related costs	2,437	818
Total operating expenses	34,609	28,037
Operating income from continuing operations	5,397	4,068
Interest income (expense), net	-1,397	-837
Foreign exchange transaction gains (losses), net	517	-19
Other income (expense), net	729	581
Income from continuing operations before income taxes	5,246	3,793
Income tax provision	1,800	937
Income from continuing operations	3,446	2,856
Loss from discontinued operations, net of tax		-1,866
Consolidated net income	3,446	990
Less: Net income attributable to noncontrolling interest		-7
Net income attributable to GSI Group Inc.	$3,446	$983
Earnings per common share from continuing operations:
Basic	$0.10	$0.08
Diluted	$0.10	$0.08
Loss per common share from discontinued operations:
Basic		($0.05)
Diluted		($0.05)
Earnings per common share attributable to GSI Group Inc.:
Basic	$0.10	$0.03
Diluted	$0.10	$0.03
Weighted average common shares outstanding—basic	34,506	34,227
Weighted average common shares outstanding—diluted	34,999	34,669

CONSOLIDATED_STATEMENTS_OF_COM

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Apr. 03, 2015		Mar. 28, 2014
Statement Of Income And Comprehensive Income [Abstract]
Consolidated net income	$3,446		$990
Other comprehensive income (loss):
Foreign currency translation adjustments, net of tax	-4,506	[1]	-63	[1]
Pension liability adjustments, net of tax	729	[2]	64	[2]
Total other comprehensive income (loss)	-3,777		1
Total consolidated comprehensive income (loss)	-331		991
Less: Comprehensive income attributable to noncontrolling interest			-7
Comprehensive income (loss) attributable to GSI Group Inc.	($331)		$984
[1]	The tax effect on this component of comprehensive income was $0.5 million for the three months ended April 3, 2015 and nominal for the three months ended March 28, 2014.
[2]	The tax effect on this component of comprehensive income was not material for all periods presented. See Note 4 for the total amount of pension liability adjustments reclassified out of accumulated other comprehensive income (loss).

CONSOLIDATED_STATEMENTS_OF_COM1

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Parenthetical) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Apr. 03, 2015
Statement Of Income And Comprehensive Income [Abstract]
Foreign currency translation adjustments - Tax effect on component of comprehensive income	$0.50

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Apr. 03, 2015	Mar. 28, 2014
Cash flows from operating activities:
Consolidated net income	$3,446	$990
Less: Loss from discontinued operations, net of tax		1,866
Income from continuing operations	3,446	2,856
Adjustments to reconcile income from continuing operations to net cash provided by operating activities of continuing operations:
Depreciation and amortization	4,762	4,829
Provision for inventory excess and obsolescence	516	465
Share-based compensation	1,597	1,439
Deferred income taxes	-103	-1,990
Earnings from equity-method investment	-727	-573
Non-cash restructuring and acquisition related charges	288	171
Other	415	437
Changes in assets and liabilities which (used) provided cash, excluding effects from businesses purchased or classified as discontinued operations:
Accounts receivable	-5,096	-4,919
Inventories	-3,975	1,449
Prepaid expenses, income taxes receivable and other current assets	649	388
Accounts payable, accrued expenses, income taxes payable and other current liabilities	4,660	-2,519
Other non-current assets and liabilities	-390	763
Cash provided by operating activities of continuing operations	6,042	2,796
Cash used in operating activities of discontinued operations		-1,299
Cash provided by operating activities	6,042	1,497
Cash flows from investing activities:
Purchases of property, plant and equipment	-946	-972
Acquisition of businesses, net of cash acquired	-13,852	-92,360
Proceeds from the sale of property, plant and equipment	23	38
Cash used in investing activities of continuing operations	-14,775	-93,294
Cash used in investing activities of discontinued operations		-617
Cash used in investing activities	-14,775	-93,911
Cash flows from financing activities:
Borrowings under revolving credit facility	13,000	70,000
Repayments of long-term debt and revolving credit facility	-4,875	-4,875
Payments for debt issuance costs		-712
Payments of withholding taxes from stock-based awards	-1,352	-1,371
Capital lease payments	-201	-246
Other financing activities	159	395
Cash provided by financing activities of continuing operations	6,731	63,191
Cash provided by financing activities of discontinued operations	0	0
Cash provided by financing activities	6,731	63,191
Effect of exchange rates on cash and cash equivalents	-1,602	-16
Decrease in cash and cash equivalents	-3,604	-29,239
Cash and cash equivalents, beginning of period	51,146	60,980
Cash and cash equivalents, end of period	47,542	31,741
Supplemental disclosure of cash flow information:
Cash paid for interest	975	489
Cash paid for income taxes	1,559	1,026
Income tax refunds received	16
Supplemental disclosure of non-cash financing activity:
Assets acquired under capital lease obligations	$17

Basis_of_Presentation

Basis of Presentation	3 Months Ended
	Apr. 03, 2015
Accounting Policies [Abstract]
Basis of Presentation	1. Basis of Presentation
	GSI Group Inc. and its subsidiaries (collectively referred to as the “Company”, “we”, “us”, “our”) design, develop, manufacture and sell precision photonic and motion control components and subsystems to Original Equipment Manufacturers (“OEMs”) in the medical and advanced industrial markets. The Company is a leader in highly engineered enabling technologies, including CO2 laser sources, laser scanning and beam delivery products, optical data collection and machine vision technologies, medical visualization and informatics solutions, and precision motion control products. The Company specializes in collaborating with OEM customers to adapt its component and subsystem technologies to deliver highly differentiated performance in their applications.
	The accompanying unaudited interim consolidated financial statements have been prepared in U.S. dollars and pursuant to the rules and regulations of the United States Securities and Exchange Commission (“SEC”), the instructions to Form 10-Q and the provisions of Regulation S-X pertaining to interim financial statements. Accordingly, certain information and footnote disclosures normally included in the financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. The interim consolidated financial statements and notes included in this report should be read in conjunction with the financial statements and notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014. In the opinion of management, these interim consolidated financial statements include all adjustments and accruals of a normal and recurring nature necessary to fairly state the results of the interim periods presented. The results for interim periods are not necessarily indicative of results to be expected for the full year or for any future periods.
	The interim consolidated financial statements include the accounts of the Company and its 50% owned joint venture, Excel Laser Technology Private Limited (the “India JV”), which is reported as discontinued operations. The Company is currently in negotiations with the joint venture partner to dissolve the joint venture. Intercompany transactions and balances have been eliminated.
	The Company owns 41% of Laser Quantum Ltd. (“Laser Quantum”), a privately held company located in the United Kingdom. The Company records the results of this entity under the equity method as it does not have a controlling interest in the entity.
	The Company’s unaudited interim financial statements are prepared on a quarterly basis ending on the Friday closest to the end of the calendar quarter, with the exception of the fourth quarter which always ends on December 31.
	Use of Estimates
	The preparation of financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the dates of the financial statements, and the reported amounts of sales and expenses during the reporting periods. The Company evaluates its estimates based on historical experience, current conditions and various other assumptions that it believes are reasonable under the circumstances. Estimates and assumptions are reviewed on an on-going basis and the effects of revisions are reflected in the period in which they are deemed to be necessary. Actual results could differ significantly from those estimates.
	Recent Accounting Pronouncements
	Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity
	In April 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-08, “Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity.” ASU 2014-08 provides guidance on determining when disposals can be presented as discontinued operations. ASU 2014-08 requires that only disposals representing a strategic shift that has (or will have) a major effect on an entity’s operations and financial results should be presented as discontinued operations. A strategic shift may include a disposal of a major line of business, a major equity method investment or a major part of an entity. Additionally, ASU 2014-08 requires expanded disclosures regarding discontinued operations. ASU 2014-08 is effective prospectively for reporting periods beginning after December 15, 2014. The Company adopted this pronouncement in January 2015.
	Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement
	In April 2015, the FASB issued ASU 2015-05, “Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement,” which provides guidance to customers about whether a cloud computing arrangement includes a software license. If a cloud computing arrangement includes a software license, the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses. If a cloud computing arrangement does not include a software license, the customer should account for the arrangement as a service contract. ASU 2015-05 will be effective for annual and interim reporting periods beginning after December 15, 2015, with early adoption permitted. Upon adoption, an entity may apply the new guidance either retrospectively or prospectively to all arrangements entered into or materially modified after the effective date. The Company is currently evaluating the impact of ASU 2015-05 on the Company’s consolidated financial statements.
	Simplifying the Presentation of Debt Issuance Costs
	In April 2015, the FASB issued ASU 2015-03, “Simplifying the Presentation of Debt Issuance Costs.” ASU 2015-03 requires debt issuance related costs to be presented in the balance sheet as a direct deduction from the carrying amount of the associated debt liability, consistent with the presentation of a debt discount. ASU 2015-03 will be effective on a retrospective basis for annual and interim reporting periods beginning after December 15, 2015, with early adoption permitted. The adoption of this amendment is not expected to have a material impact on the Company’s consolidated financial statements.
	Revenue from Contracts with Customers
	In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers”, which provides guidance for revenue recognition. ASU 2014-09 supersedes the revenue recognition requirements in Accounting Standards Codification (“ASC”) 605, “Revenue Recognition,” and requires entities to recognize revenue in a way that depicts the transfer of goods or services to customers at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 will be effective for annual and interim reporting periods beginning after December 15, 2016. Early adoption is not permitted. Upon adoption, an entity may apply the new guidance either retrospectively to each prior reporting period presented or retrospectively only to customer contracts not yet completed as of the date of adoption with the cumulative effect of initially applying the standard recognized in beginning retained earnings at the date of the initial application. In April 2015, the FASB proposed a deferral, which is not yet effective, of the effective date of ASU 2014-09 and permitted early adoption. The proposed deferral would result in ASU 2014-09 being effective for annual and interim reporting periods beginning after December 15, 2017. The Company is currently evaluating the impact of the new standard on the Company’s financial statements.
	Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern
	In August 2014, the FASB issued ASU 2014-15, "Presentation of Financial Statements - Going Concern (Subtopic 205-40)," which requires management to assess a company’s ability to continue as a going concern and to provide related footnote disclosures in certain circumstances. ASU 2014-15 will be effective for annual reporting periods ending after December 15, 2016. Early application is permitted. The Company does not expect the adoption of ASU 2014-15 to have an impact on the Company’s financial statements.

Business_Combinations

Business Combinations	3 Months Ended
	Apr. 03, 2015
Business Combinations [Abstract]
Business Combinations	2. Business Combinations
	On February 19, 2015, the Company acquired 100% of the outstanding stock of Applimotion Inc. (“Applimotion”), a Loomis, California based provider of advanced precision motor and motion control technology to OEM customers in the advanced industrial and medical markets, for a total purchase price of $14.8 million, subject to customary working capital adjustments. The purchase price includes $13.9 million in cash paid upon closing of the acquisition and $0.9 million estimated fair value of future contingent consideration payable upon the achievement of certain revenue targets for fiscal years 2015 to 2017. The undiscounted range of possible contingent consideration is zero to $4.0 million. The Company expects that the addition of Applimotion will enable the Company to offer a broader range of motion control technologies and integrated solutions. The Company recognized acquisition costs of $0.2 million during the three months ended April 3, 2015 related to the acquisition. Acquisition-related costs are included in restructuring, acquisition and divestiture related costs in the consolidated statements of operations.
	The acquisition of Applimotion has been accounted for as a business combination. The allocation of the purchase price is based upon a valuation of assets and liabilities acquired. Assets acquired and liabilities assumed have been recorded at their estimated fair values as of the acquisition date. The fair values of intangible assets were based on valuations using an income approach, with estimates and assumptions provided by management of Applimotion and the Company. The process for estimating the fair values of identifiable intangible assets and the contingent consideration liability requires the use of significant estimates and assumptions, including estimating future cash flows and developing appropriate discount rates. The excess of the purchase price over the tangible assets, identifiable intangible assets and assumed liabilities was recorded as goodwill. The Company’s estimates and assumptions in determining the estimated fair values of certain assets and liabilities are subject to change within the measurement period (up to one year from the acquisition date) as a result of additional information obtained with regards to facts and circumstances that existed as of the acquisition date. The purchase price allocation is preliminary and the primary areas of the purchase price allocation that are not yet finalized relate to the final settlement of working capital, valuation of intangible assets and contingent consideration, income taxes, and the amount of the residual goodwill.
	Based upon a preliminary valuation, the total purchase price was allocated as follows (in thousands):
		Purchase Price
		Allocation
	Cash	$	317
	Accounts receivable		1,821
	Inventory		2,041
	Prepaid expenses and other current assets		89
	Property and equipment		308
	Intangible assets		6,071
	Goodwill		7,553
	Total assets acquired		18,200
	Accounts payable		964
	Other liabilities		717
	Deferred tax liabilities		2,248
	Total liabilities assumed		3,929
	Total assets acquired and liabilities assumed		14,271
	Less: cash acquired		317
	Plus: working capital adjustment		863
	Total purchase price, net of cash acquired		14,817
	Less: contingent consideration		965
	Net cash used for acquisition of business	$	13,852
	As of April 3, 2015, the working capital adjustments had not been finalized and were estimated to be an additional cash receipt of $0.9 million which has been included in prepaid expenses and other current assets in the balance sheet.
	The preliminary fair value of intangible assets is comprised of the following (dollar amounts in thousands):
				Weighted Average
		Estimated Fair		Amortization
		Value		Period
	Developed technology	$	2,684	10 years
	Customer relationships		2,066	10 years
	Non-compete covenant		684	4 years
	Backlog		637	1 year
	Total	$	6,071
	The purchase price allocation resulted in $7.6 million of goodwill and $6.1 million of identifiable intangible assets, none of which is expected to be deductible for tax purposes. Intangible assets are being amortized over their weighted average useful lives primarily based upon the pattern in which anticipated economic benefits from such assets are expected to be realized. The goodwill recorded represents the anticipated incremental value of future cash flow potential attributable to: (i) Applimotion’s ability to grow their business with existing and new customers, (ii) the potential to realize cost improvements due to scale and more efficient operations, (iii) the opportunity to serve customers with integrated assemblies that feature products from both Applimotion and the Company and (iv) the potential to sell the Company’s products into Applimotion’s customer base.
	The results of the Applimotion acquisition were included in the Company’s results of operations beginning on February 19, 2015. The pro forma financial information reflecting the operating results of Applimotion, had it been acquired as of January 1, 2014, would not differ materially from the operating results of the Company as reported for the year ended December 31, 2014. Applimotion is included in the Company’s Precision Motion reportable segment.

Assets_Held_for_Sale_and_Disco

Assets Held for Sale and Discontinued Operations	3 Months Ended
	Apr. 03, 2015
Assets Held For Sale And Discontinued Operations [Abstract]
Assets Held for Sale and Discontinued Operations	3. Assets Held for Sale and Discontinued Operations
	On April 15, 2015, the Company completed the sale of certain assets and liabilities of its JK Lasers business for approximately $31.4 million in cash, subject to customary working capital adjustments. The Company began accounting for the JK Lasers business, which is included in the Laser Products reportable segment, as an asset held for sale in the first quarter of 2015. The JK Lasers business divestiture does not qualify for discontinued operations accounting treatment.
	In July 2014, the Company completed the sale of certain assets and liabilities of its Scientific Lasers business for approximately $6.5 million in cash, net of working capital adjustments.  In accordance with the purchase and sale agreement, $1.5 million of the sales proceeds is held in escrow until January 2016. The $1.5 million escrow is included in prepaid expenses and other current assets on the balance sheet as of April 3, 2015 and other long-term assets as of December 31, 2014.
	The major components of the assets and liabilities held for sale as of April 3, 2015 and December 31, 2014, respectively, were as follows (in thousands):
		April 3,			December 31,
		2015			2014
	Accounts receivable, net	$	4,268		$	95
	Inventories		6,936			161
	Prepaid and other current assets		452			8
	Other assets		1,926			367
	Assets held for sale	$	13,582		$	631
	Accounts payable	$	1,522		$	16
	Accrued expenses and other current liabilities		1,198			74
	Other liabilities		234			234
	Liabilities held for sale	$	2,954		$	324
	Assets and liabilities held for sale as of April 3, 2015 included the balances of the JK Lasers business and the India JV. Assets and liabilities held for sale as of December 31, 2014 included the balances of the India JV.
	The following table presents the operating results which are reported as discontinued operations in the Company’s consolidated statements of operations (in thousands):
		Three Months Ended
		March 28,
		2014
	Sales from discontinued operations	$	4,016
	Operating loss from discontinued operations, before income tax	$	(2,851	)
	Operating loss from discontinued operations, net of tax	$	(1,866	)
	The operating loss from discontinued operations during the three months ended March 28, 2014 included a $1.6 million fair value write-down of the Scientific Lasers business to its estimated fair value less costs to sell.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Income (Loss)	3 Months Ended
	Apr. 03, 2015
Equity [Abstract]
Accumulated Other Comprehensive Income (Loss)	4. Accumulated Other Comprehensive Income (Loss)
	Changes in accumulated other comprehensive income (loss) was as follows (in thousands):
		Total accumulated
		other			Foreign currency
		comprehensive			translation			Pension
		income (loss)			adjustments			liability
	Balance at December 31, 2014	$	(16,456	)	$	(5,615	)	$	(10,841	)
	Other comprehensive income (loss)		(3,994	)		(4,506	)		512
	Amounts reclassified from other comprehensive income (loss) (1)		217			—			217
	Balance at April 3, 2015	$	(20,233	)	$	(10,121	)	$	(10,112	)
	-1	The amounts reclassified from other comprehensive income (loss) were included in selling, general and administrative expenses in the consolidated statements of operations.

Earnings_per_Share

Earnings per Share	3 Months Ended
	Apr. 03, 2015
Earnings Per Share [Abstract]
Earnings per Share	5. Earnings per Share
	Basic earnings (loss) per common share is computed by dividing net income (loss) by the weighted average number of common shares outstanding during the period. For diluted earnings per common share, the denominator also includes the dilutive effect of outstanding deferred stock units and restricted stock units determined using the treasury stock method. Dilutive effects of contingently issuable shares are included in the weighted average dilutive share calculation when the contingencies have been resolved. For periods in which net losses are generated, the dilutive potential common shares are excluded from the calculation of diluted earnings per share as the effect would be anti-dilutive.
	The following table sets forth the computation of basic and diluted earnings per share (in thousands, except per share amounts):
		Three Months Ended
		April 3,		March 28,
		2015		2014
	Numerators:
	Income from continuing operations	$	3,446	$	2,856
	Consolidated loss from discontinued operations		—		(1,866	)
	Less: Income attributable to noncontrolling interest		—		(7	)
	Loss from discontinued operations attributable to GSI Group Inc.		—		(1,873	)
	Net income attributable to GSI Group Inc.	$	3,446	$	983
	Denominators:
	Weighted average common shares outstanding— basic		34,506		34,227
	Dilutive potential common shares		493		442
	Weighted average common shares outstanding— diluted		34,999		34,669
	Antidilutive common shares excluded from above		—		87
	Basic Earnings (Loss) per Common Share:
	From continuing operations	$	0.1	$	0.08
	From discontinued operations	$	—	$	(0.05	)
	Basic earnings per share attributable to GSI Group Inc.	$	0.1	$	0.03
	Diluted Earnings (Loss) per Common Share:
	From continuing operations	$	0.1	$	0.08
	From discontinued operations	$	—	$	(0.05	)
	Diluted earnings per share attributable to GSI Group Inc.	$	0.1	$	0.03
	Common Stock Repurchases
	In October 2013, the Company’s Board of Directors authorized a share repurchase plan under which the Company may repurchase outstanding shares of the Company’s common stock up to an aggregate amount of $10.0 million. The shares may be repurchased from time to time, at the Company’s discretion, based on ongoing assessment of the capital needs of the business, the market price of the Company’s common stock, and general market conditions. Shares may also be repurchased through an accelerated stock purchase agreement, on the open market or in privately negotiated transactions in accordance with applicable federal securities laws. Repurchases may be made under certain SEC regulations, which would permit common stock to be purchased when the Company would otherwise be prohibited from doing so under insider trading laws. The share repurchase plan does not obligate the Company to acquire any particular amount of common stock. No time limit was set for the completion of the share repurchase program, and the program may be suspended or discontinued at any time. As of December 31, 2014, the Company had cumulatively repurchased 50 thousand shares of its common stock for an aggregate amount of $0.5 million. There have been no share repurchases to date in 2015.

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Apr. 03, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	6. Fair Value Measurements
	ASC 820, “Fair Value Measurements,” establishes a fair value hierarchy based on three levels of inputs, of which the first two are considered observable and the third is considered unobservable:
	·	Level 1: Quoted prices for identical assets or liabilities in active markets which the Company can access.
	·	Level 2: Observable inputs other than those described in Level 1.
	·	Level 3: Unobservable inputs.
	The Company’s cash equivalents are investments in money market accounts, which represent the only asset the Company measures at fair value on a recurring basis. The Company determines the fair value of our cash equivalents using a market approach based on quoted prices in active markets which is classified as Level 1. The contingent consideration is classified as Level 3 as the fair value is based on unobservable inputs. The fair values of cash, accounts receivable, income taxes receivable, accounts payable, income taxes payable, accrued expenses and other current liabilities approximate their carrying values because of their short-term nature.
	The following table summarizes the fair values of our financial assets and liabilities as of April 3, 2015 (in thousands):
				Quoted Prices in				Significant Other
				Active Markets for		Significant Other		Unobservable
				Identical Assets		Observable Inputs		Inputs
		Fair Value		(Level 1)		(Level 2)		(Level 3)
	Assets
	Cash equivalents	$	722	$	722	$	—	$	—
	Total Assets	$	722	$	722	$	—	$	—
	Liabilities
	Contingent consideration	$	965	$	—	$	—	$	965
	Total Liabilities	$	965	$	—	$	—	$	965
	The following table summarizes the fair values of our financial assets as of December 31, 2014 (in thousands):
				Quoted Prices in				Significant Other
				Active Markets for		Significant Other		Unobservable
				Identical Assets		Observable Inputs		Inputs
		Fair Value		(Level 1)		(Level 2)		(Level 3)
	Assets
	Cash equivalents	$	2,255	$	2,255	$	—	$	—
	Contingent consideration relates to the Company’s acquisition of Applimotion on February 19, 2015. The former shareholders of Applimotion are eligible to receive contingent consideration based on the achievement of certain revenue targets for fiscal years 2015 to 2017. If such targets are achieved, the contingent consideration will be payable in cash in two installments in 2017 and 2018, respectively. The estimated fair value of the contingent consideration was determined based on the Monte Carlo valuation method and has been recorded as part of the purchase price and as a long-term liability in the consolidated balance sheet as of the acquisition date. The fair value of the contingent consideration was still preliminary as of April 3, 2015. Once the final fair value is determined, subsequent changes in the estimated fair value of this contingent liability will be recorded in the consolidated statement of operations as acquisition related costs until the liability is fully settled.
	See Note 9 to Consolidated Financial Statements for a discussion of the estimated fair value of the Company’s outstanding debt.

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets	3 Months Ended
	Apr. 03, 2015
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	7. Goodwill and Intangible Assets
	Goodwill
	Goodwill is recorded when the consideration for a business combination exceeds the fair value of net tangible and identifiable intangible assets acquired. The Company tests its goodwill balances annually for impairment as of the beginning of the second quarter or more frequently if indicators are present or changes in circumstances suggest that impairment may exist. During the fourth quarter of 2014, the Company performed an interim impairment review of the goodwill and intangible assets related to the NDS reporting unit and recorded a $19.6 million goodwill impairment charge in the fourth quarter of 2014.
	The following table summarizes changes in goodwill during the three months ended April 3, 2015 (in thousands):
	Balance at beginning of the period	$	90,746
	Goodwill acquired from the Applimotion acquisition		7,553
	Balance at end of the period	$	98,299
	Goodwill acquired from the Applimotion acquisition is reflected in the Precision Motion segment. Goodwill by reportable segment as of April 3, 2015 was as follows (in thousands):
		Reportable Segment
		Laser			Medical			Precision			Total
		Products			Technologies			Motion
	Goodwill	$	132,954		$	82,730		$	33,844		$	249,528
	Accumulated impairment of goodwill		(102,461	)		(31,722	)		(17,046	)		(151,229	)
	Total	$	30,493		$	51,008		$	16,798		$	98,299
	Goodwill by reportable segment as of December 31, 2014 was as follows (in thousands):
		Reportable Segment
		Laser			Medical			Precision			Total
		Products			Technologies			Motion
	Goodwill	$	132,954		$	82,730		$	26,291		$	241,975
	Accumulated impairment of goodwill		(102,461	)		(31,722	)		(17,046	)		(151,229	)
	Total	$	30,493		$	51,008		$	9,245		$	90,746
	Intangible Assets
	Intangible assets as of April 3, 2015 and December 31, 2014, respectively, are summarized as follows (in thousands):
		3-Apr-15									31-Dec-14
		Gross Carrying			Accumulated			Net Carrying			Gross Carrying			Accumulated			Net Carrying
		Amount			Amortization			Amount			Amount			Amortization			Amount
	Amortizable intangible assets:
	Patents and acquired technologies	$	80,538		$	(62,730	)	$	17,808		$	78,253		$	(62,010	)	$	16,243
	Customer relationships		64,977			(32,772	)		32,205			63,029			(31,531	)		31,498
	Customer backlog		2,447			(1,901	)		546			1,810			(1,641	)		169
	Non-compete covenant		2,514			(479	)		2,035			1,830			(366	)		1,464
	Trademarks and trade names		10,125			(5,462	)		4,663			10,205			(5,364	)		4,841
	Amortizable intangible assets		160,601			(103,344	)		57,257			155,127			(100,912	)		54,215
	Non-amortizable intangible assets:
	Trade names		13,027			—			13,027			13,027			—			13,027
	Totals	$	173,628		$	(103,344	)	$	70,284		$	168,154		$	(100,912	)	$	67,242
	All definite-lived intangible assets are amortized either on a straight-line basis or an economic benefit basis over their remaining useful life. Amortization expense for customer relationships and definite-lived trademarks, trade names and other intangibles is included in operating expenses in the accompanying consolidated statements of operations. Amortization expense for patents and acquired technologies is included in cost of goods sold in the accompanying consolidated statements of operations. Amortization expense is as follows (in thousands):
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Amortization expense – cost of sales	$	1,119		$	1,301
	Amortization expense – operating expenses		1,889			1,744
	Total amortization expense	$	3,008		$	3,045
	Estimated amortization expense for each of the five succeeding years and thereafter as of April 3, 2015 was as follows (in thousands):
	Year Ending December 31,		Cost of Sales			Operating			Total
						Expenses
	2015 (remainder of year)		$	3,524		$	5,552		$	9,076
	2016			3,550			7,253			10,803
	2017			3,229			6,632			9,861
	2018			1,754			5,998			7,752
	2019			1,487			4,008			5,495
	Thereafter			4,264			10,006			14,270
	Total		$	17,808		$	39,449		$	57,257

Supplementary_Balance_Sheet_In

Supplementary Balance Sheet Information	3 Months Ended
	Apr. 03, 2015
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Supplementary Balance Sheet Information	8. Supplementary Balance Sheet Information
	The following tables provide the details of selected balance sheet items as of the periods indicated (in thousands):
	Inventories
		April 3,			December 31,
		2015			2014
	Raw materials	$	37,444		$	38,934
	Work-in-process		10,293			9,899
	Finished goods		11,551			11,945
	Demo and consigned inventory		1,394			2,165
	Total inventories	$	60,682		$	62,943
	Accrued Expenses and Other Current Liabilities
		April 3,			December 31,
		2015			2014
	Accrued compensation and benefits	$	8,269		$	7,741
	Accrued warranty		2,825			3,044
	Accrued professional services		2,201			1,827
	Other		8,229			6,789
	Total	$	21,524		$	19,401
	Accrued Warranty
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Balance at beginning of the period	$	3,044		$	3,315
	Provision charged to cost of sales		429			481
	Acquisition related warranty accrual		94			90
	Use of provision		(342	)		(571	)
	Reclassification to liabilities held for sale		(376	)		—
	Foreign currency exchange rate changes		(24	)		(5	)
	Balance at end of period	$	2,825		$	3,310
	Other Long Term Liabilities
		April 3,			December 31,
		2015			2014
	Capital lease obligations	$	9,458		$	9,507
	Accrued pension liabilities		5,409			6,037
	Other		3,828			3,275
	Total	$	18,695		$	18,819

Debt

Debt	3 Months Ended
	Apr. 03, 2015
Debt Disclosure [Abstract]
Debt	9. Debt
	Debt consisted of the following (in thousands):
		April 3,		December 31,
		2015		2014
	Senior Credit Facilities – term loan	$	33,125	$	35,000
	Senior Credit Facilities – revolving credit facility		90,000		80,000
	Total Senior Credit Facilities	$	123,125	$	115,000
	Senior Credit Facilities
	The Company’s amended and restated senior secured credit agreement (the “Amended and Restated Credit Agreement”) provides for a $50.0 million, 5-year, term loan facility due in quarterly installments of $1.9 million beginning in January 2013 and a $175.0 million, 5-year, revolving credit facility (collectively, the “Senior Credit Facilities”) that matures in December 2017. Quarterly installments due in the next twelve months under the term loan amount to $7.5 million and are classified as a current liability in the consolidated balance sheet. The increase in the revolving credit facility was related to additional borrowings to fund the Applimotion acquisition.
	The Company is required to satisfy certain financial and non-financial covenants under the Amended and Restated Credit Agreement. The Company is in compliance with these covenants as of April 3, 2015.
	Fair Value of Debt
	As of April 3, 2015 and December 31, 2014, the outstanding balance of the Company’s debt approximated its fair value based on current rates available to the Company for debt of the same maturity.

ShareBased_Compensation

Share-Based Compensation	3 Months Ended
	Apr. 03, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Share-Based Compensation	10. Share-Based Compensation
	The table below summarizes activities relating to restricted stock units issued and outstanding under the Company’s Amended and Restated 2010 Incentive Plan during the three months ended April 3, 2015:
		Restricted			Weighted
		Stock Units			Average Grant
		(In thousands)			Date Fair Value
	Unvested at December 31, 2014		749		$	10.8
	Granted		287		$	13.29
	Vested		(294	)	$	11.1
	Forfeited		(27	)	$	11.03
	Unvested at April 3, 2015		715		$	11.67
	Expected to vest as of April 3, 2015		691
	The total fair value of restricted stock units that vested during the three months ended April 3, 2015, based on the market price of the underlying stock on the date of vesting, was $3.7 million.
	The table below summarizes share-based compensation expense recorded in income from continuing operations in the consolidated statements of operations (in thousands):
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Selling, general and administrative	$	1,484		$	1,356
	Research and development and engineering		49			50
	Cost of sales		64			33
	Restructuring, acquisition and divestiture related costs		(44	)		46
	Total share-based compensation expense	$	1,553		$	1,485
	The expense recorded during each of the three-month periods ended April 3, 2015 and March 28, 2014, respectively, included $0.5 million related to deferred stock units granted to the members of the Company’s Board of Directors, pursuant to the Company’s Amended and Restated 2010 Incentive Plan. The expense associated with the respective deferred stock units was recognized in full on the date of grant, as the deferred stock units were fully vested and non-forfeitable upon grant.
	The Company acquired 100% of the outstanding stock of JADAK on March 14, 2014. In addition to the total purchase price, the Company granted restricted stock units in an aggregate of 180,000 shares to the former owner-managers of JADAK as employment inducement awards. These restricted stock units are performance based awards and will vest after two years if certain financial targets and service conditions have been achieved. As of December 31, 2014 and April 3, 2015 an aggregate of 45,000 shares, and 90,000 shares, respectively, were forfeited due to the departure of two former owner-managers of JADAK.

Income_Taxes

Income Taxes	3 Months Ended
	Apr. 03, 2015
Income Tax Disclosure [Abstract]
Income Taxes	11. Income Taxes
	The Company determines its estimated annual effective tax rate at the end of each interim period based on full-year forecasted pre-tax income and facts known at that time. The estimated annual effective tax rate is applied to the year-to-date pre-tax income at the end of each interim period. The tax effect of significant unusual items is reflected in the period in which they occur. Since the Company is incorporated in Canada, it is required to use Canada’s statutory tax rate of 27.0% in the determination of the estimated annual effective tax rate.
	The Company’s effective tax rate on income from continuing operations of 34.3% for the three months ended April 3, 2015 differs from the Canadian statutory rate of 27.0% primarily due to the mix of income earned in jurisdictions with varying tax rates, losses in jurisdictions with a full valuation allowance, and the impact of discrete items for the period. The Company’s effective tax rate on income from continuing operations of 24.7% for the three months ended March 28, 2014 differs from the Canadian statutory rate primarily due to the mix of income earned in jurisdictions with varying tax rates, losses in jurisdictions with a full valuation allowance, and the impact of discrete items for the period.
	The Company maintains a valuation allowance on some of its deferred tax assets in certain jurisdictions. A valuation allowance is required when, based upon an assessment of various factors, including recent operating loss history, anticipated future earnings, and prudent and reasonable tax planning strategies, it is more likely than not that some portion of the deferred tax assets will not be realized.
	In conjunction with the Company’s ongoing review of its actual results and anticipated future earnings, the Company continuously reassesses the possibility of releasing the remaining valuation allowance currently in place on its deferred tax assets. A release would be reported as a reduction to income tax expense without any impact on cash flows in the quarter in which it is released.

Restructuring_Acquisition_and_

Restructuring, Acquisition and Divestiture Related Costs	3 Months Ended
	Apr. 03, 2015
Restructuring And Related Activities [Abstract]
Restructuring, Acquisition and Divestiture Related costs	12. Restructuring, Acquisition and Divestiture Related Costs
	The following table summarizes restructuring, acquisition and divestiture related costs in the accompanying consolidated statements of operations (in thousands):
		Three Months Ended
		April 3,			March 28,
		2015			2014
	2011 restructuring	$	383		$	28
	2015 restructuring		1,370			—
	Total restructuring charges		1,753			28
	Acquisition charges		207			703
	JADAK earn-out costs		(80	)		87
	JK Lasers divestiture related charges		557			—
	Total acquisition and divestiture related charges		684			790
	Total restructuring, acquisition and divestiture related costs	$	2,437		$	818
	2011 Restructuring
	In November 2011, the Company announced a strategic initiative (“2011 restructuring”), which aimed to consolidate operations to reduce the Company’s cost structure and improve operational efficiency. As part of this initiative, the Company eliminated facilities through the consolidation of certain manufacturing, sales and distribution facilities and the exit of Semiconductor and Laser Systems businesses. The Company substantially completed the 2011 restructuring program by the end of 2013. Restructuring costs for the three months ended April 3, 2015 included facility costs of $0.4 million related to the Company’s vacant Orlando, Florida facility, which the Company owns and was previously occupied by the Laser Systems business. These costs were recorded in the Corporate, Shared Services and Unallocated segment.
	2015 Restructuring
	During the first quarter of 2015, the Company initiated a program to eliminate redundant costs, as a result of acquisition and divestiture activities, to better align our operations to our strategic growth plans, to further integrate our business lines, and as a consequence of our productivity initiatives. During the three months ended April 3, 2015, the Company incurred $1.3 million in severance costs related to the 2015 restructuring. Restructuring costs of $0.6 million, $0.4 million, $0.1 million and $0.3 million related to the Laser Products, Medical Technologies, Precision Motion and Corporate, Shared Services and Unallocated reportable segments, respectively.
	Rollforward of Accrued Expenses Related to Restructuring
	The following table summarizes the accrual activities, by component, related to the Company’s restructuring plans recorded in the accompanying consolidated balance sheets (in thousands):
		Total			Severance			Facility			Depreciation			Other
	Balance at December 31, 2014	$	231		$	102		$	105		$	—		$	24
	Restructuring charges		1,753			1,328			58			332			35
	Cash payments		(542	)		(366	)		(130	)		—			(46	)
	Non-cash write-offs and other adjustments		(328	)		4			—			(332	)		—
	Balance at April 3, 2015	$	1,114		$	1,068		$	33		$	—		$	13

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Apr. 03, 2015
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	13. Commitments and Contingencies
	Leases
	The Company leases certain equipment and facilities under operating and capital lease agreements. There have been no material changes to the Company’s leases through April 3, 2015 from those discussed in Note 15 to Consolidated Financial Statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014.
	Purchase Commitments
	There have been no material changes to the Company’s purchase commitments from those discussed in Note 15 to Consolidated Financial Statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014.
	Legal Proceedings
	The Company is subject to various legal proceedings and claims that arise in the ordinary course of business. The Company does not believe that the outcome of these claims will have a material adverse effect upon its financial condition or results of operations but there can be no assurance that any such claims, or any similar claims, would not have a material adverse effect upon its financial condition or results of operations.
	Guarantees and Indemnifications
	In the normal course of its operations, the Company executes agreements that provide for indemnification and guarantees to counterparties in transactions such as business dispositions, sale of assets, sale of products and operating leases. Additionally, the by-laws of the Company require it to indemnify certain current or former directors, officers, and employees of the Company against expenses incurred by them in connection with each proceeding in which he or she is involved as a result of serving or having served in certain capacities. Indemnification is not available with respect to a proceeding as to which it has been adjudicated that the person did not act in good faith in the reasonable belief that the action was in the best interests of the Company. Certain of our officers and directors are also a party to indemnification agreements with the Company. These indemnification agreements provide, among other things, that the director and officer shall be indemnified to the fullest extent permitted by applicable law against all expenses, judgments, fines and amounts paid in settlement actually and reasonably incurred by such officer or director in connection with any proceeding by reason of his or her relationship with the Company. In addition, the indemnification agreements provide for the advancement of expenses incurred by such director or officer in connection with any proceeding covered by the indemnification agreement, subject to the conditions set forth therein and to the extent such advancement is not prohibited by law. The indemnification agreements also set out the procedures for determining entitlement to indemnification, the requirements relating to notice and defense of claims for which indemnification is sought, the procedures for enforcement of indemnification rights, the limitations on and exclusions from indemnification, and the minimum levels of directors’ and officers’ liability insurance to be maintained by the Company.

Segment_Information

Segment Information	3 Months Ended
	Apr. 03, 2015
Segment Reporting [Abstract]
Segment Information	14. Segment Information
	The Company evaluates the performance of, and allocates resources to, its segments based on sales, gross profit and operating profit. The Company reports assets on a consolidated basis to the chief operating decision maker, which is the Chief Executive Officer. The Company’s reportable segments have been identified based on commonality of end markets, customers, applications and technologies amongst the Company’s individual product lines, which is consistent with the Company’s operating structure, associated management structure, and management compensation programs.
	We operate in three reportable segments: Laser Products, Medical Technologies, and Precision Motion. The reportable segments and their principal activities consist of the following:
	Laser Products
	The Laser Products segment designs, manufactures and markets photonics-based solutions to customers worldwide. The segment serves highly demanding photonics-based applications such as industrial material processing, and medical and life science imaging and laser procedures. The vast majority of the segment’s product offerings are sold to OEM customers. The segment sells these products both directly, utilizing a highly technical sales force, and indirectly, through resellers and distributors.
	Medical Technologies
	The Medical Technologies segment designs, manufactures and markets a range of medical grade technologies, including visualization solutions, imaging informatics products, optical data collection and machine vision technologies, thermal printers, and light and color measurement instrumentation to customers worldwide. The vast majority of the segment’s product offerings are sold to OEM customers. The segment sells these products both directly, utilizing a highly technical sales force, and indirectly, through resellers and distributors.
	Precision Motion
	The Precision Motion segment designs, manufactures and markets optical encoders, precision motor and motion control technology, air bearing spindles and precision machined components to customers worldwide. The vast majority of the segment’s product offerings are sold into the industrial and, to a lesser extent, the medical markets. The segment sells these products both directly, utilizing a highly technical sales force, and indirectly, through resellers and distributors.
	Reportable Segment Financial Information
	Sales, gross profit, gross profit margin, operating income (loss) from continuing operations, and depreciation and amortization by reportable segments are as follows (in thousands):
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Sales
	Laser Products	$	44,955		$	41,860
	Medical Technologies		31,111			22,367
	Precision Motion		18,548			14,906
	Total	$	94,614		$	79,133
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Gross Profit
	Laser Products	$	19,375		$	17,013
	Medical Technologies		12,513			8,889
	Precision Motion		8,465			6,416
	Corporate, Shared Services and Unallocated		(347	)		(213	)
	Total	$	40,006		$	32,105
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Gross Profit Margin
	Laser Products		43.1	%		40.6	%
	Medical Technologies		40.2	%		39.7	%
	Precision Motion		45.6	%		43	%
	Total		42.3	%		40.6	%
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Operating Income (Loss) from Continuing Operations
	Laser Products	$	8,395		$	7,124
	Medical Technologies		(654	)		(117	)
	Precision Motion		4,137			2,643
	Corporate, Shared Services and Unallocated		(6,481	)		(5,582	)
	Total	$	5,397		$	4,068
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Depreciation and Amortization
	Laser Products	$	1,582		$	1,666
	Medical Technologies		2,258			2,091
	Precision Motion		473			502
	Corporate, Shared Services and Unallocated		449			570
	Total	$	4,762		$	4,829

Basis_of_Presentation_Policies

Basis of Presentation (Policies)	3 Months Ended
	Apr. 03, 2015
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates
	The preparation of financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the dates of the financial statements, and the reported amounts of sales and expenses during the reporting periods. The Company evaluates its estimates based on historical experience, current conditions and various other assumptions that it believes are reasonable under the circumstances. Estimates and assumptions are reviewed on an on-going basis and the effects of revisions are reflected in the period in which they are deemed to be necessary. Actual results could differ significantly from those estimates.
Recent Accounting Pronouncements	Recent Accounting Pronouncements
	Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity
	In April 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-08, “Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity.” ASU 2014-08 provides guidance on determining when disposals can be presented as discontinued operations. ASU 2014-08 requires that only disposals representing a strategic shift that has (or will have) a major effect on an entity’s operations and financial results should be presented as discontinued operations. A strategic shift may include a disposal of a major line of business, a major equity method investment or a major part of an entity. Additionally, ASU 2014-08 requires expanded disclosures regarding discontinued operations. ASU 2014-08 is effective prospectively for reporting periods beginning after December 15, 2014. The Company adopted this pronouncement in January 2015.
	Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement
	In April 2015, the FASB issued ASU 2015-05, “Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement,” which provides guidance to customers about whether a cloud computing arrangement includes a software license. If a cloud computing arrangement includes a software license, the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses. If a cloud computing arrangement does not include a software license, the customer should account for the arrangement as a service contract. ASU 2015-05 will be effective for annual and interim reporting periods beginning after December 15, 2015, with early adoption permitted. Upon adoption, an entity may apply the new guidance either retrospectively or prospectively to all arrangements entered into or materially modified after the effective date. The Company is currently evaluating the impact of ASU 2015-05 on the Company’s consolidated financial statements.
	Simplifying the Presentation of Debt Issuance Costs
	In April 2015, the FASB issued ASU 2015-03, “Simplifying the Presentation of Debt Issuance Costs.” ASU 2015-03 requires debt issuance related costs to be presented in the balance sheet as a direct deduction from the carrying amount of the associated debt liability, consistent with the presentation of a debt discount. ASU 2015-03 will be effective on a retrospective basis for annual and interim reporting periods beginning after December 15, 2015, with early adoption permitted. The adoption of this amendment is not expected to have a material impact on the Company’s consolidated financial statements.
	Revenue from Contracts with Customers
	In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers”, which provides guidance for revenue recognition. ASU 2014-09 supersedes the revenue recognition requirements in Accounting Standards Codification (“ASC”) 605, “Revenue Recognition,” and requires entities to recognize revenue in a way that depicts the transfer of goods or services to customers at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 will be effective for annual and interim reporting periods beginning after December 15, 2016. Early adoption is not permitted. Upon adoption, an entity may apply the new guidance either retrospectively to each prior reporting period presented or retrospectively only to customer contracts not yet completed as of the date of adoption with the cumulative effect of initially applying the standard recognized in beginning retained earnings at the date of the initial application. In April 2015, the FASB proposed a deferral, which is not yet effective, of the effective date of ASU 2014-09 and permitted early adoption. The proposed deferral would result in ASU 2014-09 being effective for annual and interim reporting periods beginning after December 15, 2017. The Company is currently evaluating the impact of the new standard on the Company’s financial statements.
	Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern
	In August 2014, the FASB issued ASU 2014-15, "Presentation of Financial Statements - Going Concern (Subtopic 205-40)," which requires management to assess a company’s ability to continue as a going concern and to provide related footnote disclosures in certain circumstances. ASU 2014-15 will be effective for annual reporting periods ending after December 15, 2016. Early application is permitted. The Company does not expect the adoption of ASU 2014-15 to have an impact on the Company’s financial statements.

Business_Combinations_Tables

Business Combinations (Tables) (Applimotion Inc.)	3 Months Ended
	Apr. 03, 2015
Applimotion Inc.
Summary of Fair Values of Assets Acquired and Liabilities Assumed Purchase Price Allocation	Based upon a preliminary valuation, the total purchase price was allocated as follows (in thousands):
		Purchase Price
		Allocation
	Cash	$	317
	Accounts receivable		1,821
	Inventory		2,041
	Prepaid expenses and other current assets		89
	Property and equipment		308
	Intangible assets		6,071
	Goodwill		7,553
	Total assets acquired		18,200
	Accounts payable		964
	Other liabilities		717
	Deferred tax liabilities		2,248
	Total liabilities assumed		3,929
	Total assets acquired and liabilities assumed		14,271
	Less: cash acquired		317
	Plus: working capital adjustment		863
	Total purchase price, net of cash acquired		14,817
	Less: contingent consideration		965
	Net cash used for acquisition of business	$	13,852
Fair Value of Intangible Assets	The preliminary fair value of intangible assets is comprised of the following (dollar amounts in thousands):
				Weighted Average
		Estimated Fair		Amortization
		Value		Period
	Developed technology	$	2,684	10 years
	Customer relationships		2,066	10 years
	Non-compete covenant		684	4 years
	Backlog		637	1 year
	Total	$	6,071

Assets_Held_for_Sale_and_Disco1

Assets Held for Sale and Discontinued Operations (Tables)	3 Months Ended
	Apr. 03, 2015
Assets Held For Sale And Discontinued Operations [Abstract]
Components of Assets and Liabilities Held for Sale and Operating Results of Discontinued Operations	The major components of the assets and liabilities held for sale as of April 3, 2015 and December 31, 2014, respectively, were as follows (in thousands):
		April 3,			December 31,
		2015			2014
	Accounts receivable, net	$	4,268		$	95
	Inventories		6,936			161
	Prepaid and other current assets		452			8
	Other assets		1,926			367
	Assets held for sale	$	13,582		$	631
	Accounts payable	$	1,522		$	16
	Accrued expenses and other current liabilities		1,198			74
	Other liabilities		234			234
	Liabilities held for sale	$	2,954		$	324
	The following table presents the operating results which are reported as discontinued operations in the Company’s consolidated statements of operations (in thousands):
		Three Months Ended
		March 28,
		2014
	Sales from discontinued operations	$	4,016
	Operating loss from discontinued operations, before income tax	$	(2,851	)
	Operating loss from discontinued operations, net of tax	$	(1,866	)

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Loss) (Tables)	3 Months Ended
	Apr. 03, 2015
Equity [Abstract]
Components of Accumulated Other Comprehensive Income (Loss)	Changes in accumulated other comprehensive income (loss) was as follows (in thousands):
		Total accumulated
		other			Foreign currency
		comprehensive			translation			Pension
		income (loss)			adjustments			liability
	Balance at December 31, 2014	$	(16,456	)	$	(5,615	)	$	(10,841	)
	Other comprehensive income (loss)		(3,994	)		(4,506	)		512
	Amounts reclassified from other comprehensive income (loss) (1)		217			—			217
	Balance at April 3, 2015	$	(20,233	)	$	(10,121	)	$	(10,112	)
	-1	The amounts reclassified from other comprehensive income (loss) were included in selling, general and administrative expenses in the consolidated statements of operations.

Earnings_per_Share_Tables

Earnings per Share (Tables)	3 Months Ended
	Apr. 03, 2015
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings Per Share	The following table sets forth the computation of basic and diluted earnings per share (in thousands, except per share amounts):
		Three Months Ended
		April 3,		March 28,
		2015		2014
	Numerators:
	Income from continuing operations	$	3,446	$	2,856
	Consolidated loss from discontinued operations		—		(1,866	)
	Less: Income attributable to noncontrolling interest		—		(7	)
	Loss from discontinued operations attributable to GSI Group Inc.		—		(1,873	)
	Net income attributable to GSI Group Inc.	$	3,446	$	983
	Denominators:
	Weighted average common shares outstanding— basic		34,506		34,227
	Dilutive potential common shares		493		442
	Weighted average common shares outstanding— diluted		34,999		34,669
	Antidilutive common shares excluded from above		—		87
	Basic Earnings (Loss) per Common Share:
	From continuing operations	$	0.1	$	0.08
	From discontinued operations	$	—	$	(0.05	)
	Basic earnings per share attributable to GSI Group Inc.	$	0.1	$	0.03
	Diluted Earnings (Loss) per Common Share:
	From continuing operations	$	0.1	$	0.08
	From discontinued operations	$	—	$	(0.05	)
	Diluted earnings per share attributable to GSI Group Inc.	$	0.1	$	0.03

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	3 Months Ended
	Apr. 03, 2015
Fair Value Disclosures [Abstract]
Fair Values of Financial Assets and Liabilities	The following table summarizes the fair values of our financial assets and liabilities as of April 3, 2015 (in thousands):
				Quoted Prices in				Significant Other
				Active Markets for		Significant Other		Unobservable
				Identical Assets		Observable Inputs		Inputs
		Fair Value		(Level 1)		(Level 2)		(Level 3)
	Assets
	Cash equivalents	$	722	$	722	$	—	$	—
	Total Assets	$	722	$	722	$	—	$	—
	Liabilities
	Contingent consideration	$	965	$	—	$	—	$	965
	Total Liabilities	$	965	$	—	$	—	$	965
	The following table summarizes the fair values of our financial assets as of December 31, 2014 (in thousands):

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Apr. 03, 2015
Goodwill And Intangible Assets Disclosure [Abstract]
Summary of Changes in Goodwill	The following table summarizes changes in goodwill during the three months ended April 3, 2015 (in thousands):
	Balance at beginning of the period	$	90,746
	Goodwill acquired from the Applimotion acquisition		7,553
	Balance at end of the period	$	98,299
Goodwill by Reportable Segment	Goodwill by reportable segment as of April 3, 2015 was as follows (in thousands):
		Reportable Segment
		Laser			Medical			Precision			Total
		Products			Technologies			Motion
	Goodwill	$	132,954		$	82,730		$	33,844		$	249,528
	Accumulated impairment of goodwill		(102,461	)		(31,722	)		(17,046	)		(151,229	)
	Total	$	30,493		$	51,008		$	16,798		$	98,299
	Goodwill by reportable segment as of December 31, 2014 was as follows (in thousands):
		Reportable Segment
		Laser			Medical			Precision			Total
		Products			Technologies			Motion
	Goodwill	$	132,954		$	82,730		$	26,291		$	241,975
	Accumulated impairment of goodwill		(102,461	)		(31,722	)		(17,046	)		(151,229	)
	Total	$	30,493		$	51,008		$	9,245		$	90,746
Intangible Assets	Intangible assets as of April 3, 2015 and December 31, 2014, respectively, are summarized as follows (in thousands):
		3-Apr-15									31-Dec-14
		Gross Carrying			Accumulated			Net Carrying			Gross Carrying			Accumulated			Net Carrying
		Amount			Amortization			Amount			Amount			Amortization			Amount
	Amortizable intangible assets:
	Patents and acquired technologies	$	80,538		$	(62,730	)	$	17,808		$	78,253		$	(62,010	)	$	16,243
	Customer relationships		64,977			(32,772	)		32,205			63,029			(31,531	)		31,498
	Customer backlog		2,447			(1,901	)		546			1,810			(1,641	)		169
	Non-compete covenant		2,514			(479	)		2,035			1,830			(366	)		1,464
	Trademarks and trade names		10,125			(5,462	)		4,663			10,205			(5,364	)		4,841
	Amortizable intangible assets		160,601			(103,344	)		57,257			155,127			(100,912	)		54,215
	Non-amortizable intangible assets:
	Trade names		13,027			—			13,027			13,027			—			13,027
	Totals	$	173,628		$	(103,344	)	$	70,284		$	168,154		$	(100,912	)	$	67,242
Amortization Expense of Intangible Assets	Amortization expense is as follows (in thousands):
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Amortization expense – cost of sales	$	1,119		$	1,301
	Amortization expense – operating expenses		1,889			1,744
	Total amortization expense	$	3,008		$	3,045
Estimated Amortization Expense	Estimated amortization expense for each of the five succeeding years and thereafter as of April 3, 2015 was as follows (in thousands):
	Year Ending December 31,		Cost of Sales			Operating			Total
						Expenses
	2015 (remainder of year)		$	3,524		$	5,552		$	9,076
	2016			3,550			7,253			10,803
	2017			3,229			6,632			9,861
	2018			1,754			5,998			7,752
	2019			1,487			4,008			5,495
	Thereafter			4,264			10,006			14,270
	Total		$	17,808		$	39,449		$	57,257

Supplementary_Balance_Sheet_In1

Supplementary Balance Sheet Information (Tables)	3 Months Ended
	Apr. 03, 2015
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Inventories	Inventories
		April 3,			December 31,
		2015			2014
	Raw materials	$	37,444		$	38,934
	Work-in-process		10,293			9,899
	Finished goods		11,551			11,945
	Demo and consigned inventory		1,394			2,165
	Total inventories	$	60,682		$	62,943
Accrued Expenses and Other Current Liabilities	Accrued Expenses and Other Current Liabilities
		April 3,			December 31,
		2015			2014
	Accrued compensation and benefits	$	8,269		$	7,741
	Accrued warranty		2,825			3,044
	Accrued professional services		2,201			1,827
	Other		8,229			6,789
	Total	$	21,524		$	19,401
Accrued Warranty	Accrued Warranty
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Balance at beginning of the period	$	3,044		$	3,315
	Provision charged to cost of sales		429			481
	Acquisition related warranty accrual		94			90
	Use of provision		(342	)		(571	)
	Reclassification to liabilities held for sale		(376	)		—
	Foreign currency exchange rate changes		(24	)		(5	)
	Balance at end of period	$	2,825		$	3,310
Summary of Other Long Term Liabilities	Other Long Term Liabilities
		April 3,			December 31,
		2015			2014
	Capital lease obligations	$	9,458		$	9,507
	Accrued pension liabilities		5,409			6,037
	Other		3,828			3,275
	Total	$	18,695		$	18,819

Debt_Tables

Debt (Tables)	3 Months Ended
	Apr. 03, 2015
Debt Disclosure [Abstract]
Debt	Debt consisted of the following (in thousands):
		April 3,		December 31,
		2015		2014
	Senior Credit Facilities – term loan	$	33,125	$	35,000
	Senior Credit Facilities – revolving credit facility		90,000		80,000
	Total Senior Credit Facilities	$	123,125	$	115,000

ShareBased_Compensation_Tables

Share-Based Compensation (Tables)	3 Months Ended
	Apr. 03, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share Based Compensation Expense Recorded In Income from Continuing Operations in Statements of Operations	The table below summarizes share-based compensation expense recorded in income from continuing operations in the consolidated statements of operations (in thousands):
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Selling, general and administrative	$	1,484		$	1,356
	Research and development and engineering		49			50
	Cost of sales		64			33
	Restructuring, acquisition and divestiture related costs		(44	)		46
	Total share-based compensation expense	$	1,553		$	1,485
2010 Incentive Award Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Issued and Outstanding	The table below summarizes activities relating to restricted stock units issued and outstanding under the Company’s Amended and Restated 2010 Incentive Plan during the three months ended April 3, 2015:
		Restricted			Weighted
		Stock Units			Average Grant
		(In thousands)			Date Fair Value
	Unvested at December 31, 2014		749		$	10.8
	Granted		287		$	13.29
	Vested		(294	)	$	11.1
	Forfeited		(27	)	$	11.03
	Unvested at April 3, 2015		715		$	11.67
	Expected to vest as of April 3, 2015		691

Restructuring_Acquisition_and_1

Restructuring, Acquisition and Divestiture Related Costs (Tables)	3 Months Ended
	Apr. 03, 2015
Restructuring And Related Activities [Abstract]
Schedule Of Restructuring And Related Cost	The following table summarizes restructuring, acquisition and divestiture related costs in the accompanying consolidated statements of operations (in thousands):
		Three Months Ended
		April 3,			March 28,
		2015			2014
	2011 restructuring	$	383		$	28
	2015 restructuring		1,370			—
	Total restructuring charges		1,753			28
	Acquisition charges		207			703
	JADAK earn-out costs		(80	)		87
	JK Lasers divestiture related charges		557			—
	Total acquisition and divestiture related charges		684			790
	Total restructuring, acquisition and divestiture related costs	$	2,437		$	818
Summary of Accrual Activities by Components Related to Company's Restructuring Plans	The following table summarizes the accrual activities, by component, related to the Company’s restructuring plans recorded in the accompanying consolidated balance sheets (in thousands):
		Total			Severance			Facility			Depreciation			Other
	Balance at December 31, 2014	$	231		$	102		$	105		$	—		$	24
	Restructuring charges		1,753			1,328			58			332			35
	Cash payments		(542	)		(366	)		(130	)		—			(46	)
	Non-cash write-offs and other adjustments		(328	)		4			—			(332	)		—
	Balance at April 3, 2015	$	1,114		$	1,068		$	33		$	—		$	13

Segment_Information_Tables

Segment Information (Tables)	3 Months Ended
	Apr. 03, 2015
Segment Reporting [Abstract]
Sales, Gross Profit, Gross Profit Margin, Operating Income (Loss) from Continuing Operations, and Depreciation and Amortization by Reportable Segments	Sales, gross profit, gross profit margin, operating income (loss) from continuing operations, and depreciation and amortization by reportable segments are as follows (in thousands):
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Sales
	Laser Products	$	44,955		$	41,860
	Medical Technologies		31,111			22,367
	Precision Motion		18,548			14,906
	Total	$	94,614		$	79,133
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Gross Profit
	Laser Products	$	19,375		$	17,013
	Medical Technologies		12,513			8,889
	Precision Motion		8,465			6,416
	Corporate, Shared Services and Unallocated		(347	)		(213	)
	Total	$	40,006		$	32,105
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Gross Profit Margin
	Laser Products		43.1	%		40.6	%
	Medical Technologies		40.2	%		39.7	%
	Precision Motion		45.6	%		43	%
	Total		42.3	%		40.6	%
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Operating Income (Loss) from Continuing Operations
	Laser Products	$	8,395		$	7,124
	Medical Technologies		(654	)		(117	)
	Precision Motion		4,137			2,643
	Corporate, Shared Services and Unallocated		(6,481	)		(5,582	)
	Total	$	5,397		$	4,068
		Three Months Ended
		April 3,			March 28,
		2015			2014
	Depreciation and Amortization
	Laser Products	$	1,582		$	1,666
	Medical Technologies		2,258			2,091
	Precision Motion		473			502
	Corporate, Shared Services and Unallocated		449			570
	Total	$	4,762		$	4,829

Basis_of_Presentation_Addition

Basis of Presentation - Additional information (Details)	3 Months Ended
	Apr. 03, 2015
Basis Of Presentation [Line Items]
Equity method investment ownership percentage on Laser Quantum	41.00%
Ownership in joint venture, Excel Laser Technology Private Limited
Basis Of Presentation [Line Items]
Minority interest ownership percentage	50.00%

Business_Combinations_Addition

Business Combinations - Additional Information (Details) (USD $)	3 Months Ended		0 Months Ended
	Apr. 03, 2015	Mar. 28, 2014	Feb. 19, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Cash paid upon closing of the acquisition	$13,852,000	$92,360,000
Goodwill	98,299,000			90,746,000
Applimotion Inc.
Business Acquisition [Line Items]
Membership interests acquired			100.00%
Total purchase price			14,817,000
Cash paid upon closing of the acquisition			13,852,000
Future contingent consideration			965,000
Undiscounted range of outcomes, minimum			0
Undiscounted range of outcomes, maximum			4,000,000
Recognized acquisition costs	200,000
Working capital adjustment	900,000		863,000
Goodwill			7,553,000
Intangible assets			6,071,000
Goodwill and intangible assets expected to be deductible for tax purposes			$0
Applimotion Inc. | Maximum
Business Acquisition [Line Items]
Estimates and assumptions, measurement period			1 year

Summary_of_Fair_Values_of_Asse

Summary of Fair Values of Assets Acquired and Liabilities Assumed Purchase Price Allocation (Details) (USD $)	0 Months Ended	3 Months Ended
In Thousands, unless otherwise specified	Feb. 19, 2015	Apr. 03, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill		$98,299	$90,746
Applimotion Inc.
Business Acquisition [Line Items]
Cash	317
Accounts receivable	1,821
Inventory	2,041
Prepaid expenses and other current assets	89
Property and equipment	308
Intangible assets	6,071
Goodwill	7,553
Total assets acquired	18,200
Accounts payable	964
Other liabilities	717
Deferred tax liabilities	2,248
Total liabilities assumed	3,929
Total assets acquired and liabilities assumed	14,271
Less: cash acquired	317
Plus: working capital adjustment	863	900
Total purchase price, net of cash acquired	14,817
Less: contingent consideration	965
Net cash used for acquisition of business	$13,852

Fair_Value_of_Intangible_Asset

Fair Value of Intangible Assets (Details) (Applimotion Inc., USD $)	0 Months Ended
In Thousands, unless otherwise specified	Feb. 19, 2015
Acquired Finite Lived Intangible Assets [Line Items]
Intangible assets	$6,071
Developed Technology
Acquired Finite Lived Intangible Assets [Line Items]
Intangible assets	2,684
Amortization Period of intangible assets	10 years
Customer Relationships
Acquired Finite Lived Intangible Assets [Line Items]
Intangible assets	2,066
Amortization Period of intangible assets	10 years
Non-compete Covenant
Acquired Finite Lived Intangible Assets [Line Items]
Intangible assets	684
Amortization Period of intangible assets	4 years
Backlog
Acquired Finite Lived Intangible Assets [Line Items]
Intangible assets	$637
Amortization Period of intangible assets	1 year

Assets_Held_for_Sale_and_Disco2

Assets Held for Sale and Discontinued Operations - Additional Information (Details) (USD $)	0 Months Ended	1 Months Ended	3 Months Ended
In Millions, unless otherwise specified	Apr. 15, 2015	Jul. 31, 2014	Apr. 03, 2015	Mar. 28, 2014
JK Lasers Business | Subsequent Event
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Sale of assets and liabilities	$31.40
Scientific Lasers Business
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Sale of assets and liabilities		6.5
Sale proceeds held in escrow		1.5
Sale proceeds held in escrow, Period			2016-01
Discontinued operations write-down value				$1.60

Components_of_Assets_and_Liabi

Components of Assets and Liabilities (Details) (USD $)	Apr. 03, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Discontinued Operations And Disposal Groups [Abstract]
Accounts receivable, net	$4,268	$95
Inventories	6,936	161
Prepaid and other current assets	452	8
Other assets	1,926	367
Assets held for sale	13,582	631
Accounts payable	1,522	16
Accrued expenses and other current liabilities	1,198	74
Other liabilities	234	234
Liabilities held for sale	$2,954	$324

Operating_Results_Historically

Operating Results Historically Included Segment (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 28, 2014
Discontinued Operations And Disposal Groups [Abstract]
Sales from discontinued operations	$4,016
Operating loss from discontinued operations, before income tax	-2,851
Operating loss from discontinued operations, net of tax	($1,866)

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income (Loss) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Apr. 03, 2015
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	($16,456)
Other comprehensive income (loss)	-3,994
Amounts reclassified from other comprehensive income (loss)	217	[1]
Ending Balance	-20,233
Foreign currency translation adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	-5,615
Other comprehensive income (loss)	-4,506
Ending Balance	-10,121
Pension liability
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	-10,841
Other comprehensive income (loss)	512
Amounts reclassified from other comprehensive income (loss)	217	[1]
Ending Balance	($10,112)
[1]	The amounts reclassified from other comprehensive income (loss) were included in selling, general and administrative expenses in the consolidated statements of operations.

Computation_of_Basic_and_Dilut

Computation of Basic and Diluted Earnings Per Share (Details) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Apr. 03, 2015	Mar. 28, 2014
Numerators:
Income from continuing operations	$3,446	$2,856
Consolidated loss from discontinued operations		-1,866
Less: Income attributable to noncontrolling interest		-7
Loss from discontinued operations attributable to GSI Group Inc.		-1,873
Net income attributable to GSI Group Inc.	$3,446	$983
Denominators:
Weighted average common shares outstanding—basic	34,506	34,227
Dilutive potential common shares	493	442
Weighted average common shares outstanding— diluted	34,999	34,669
Antidilutive common shares excluded from above		87
Basic Earnings (Loss) per Common Share:
From continuing operations	$0.10	$0.08
From discontinued operations		($0.05)
Basic earnings per share attributable to GSI Group Inc.	$0.10	$0.03
Diluted Earnings (Loss) per Common Share:
From continuing operations	$0.10	$0.08
From discontinued operations		($0.05)
Diluted earnings per share attributable to GSI Group Inc.	$0.10	$0.03

Earnings_Per_Share_Additional_

Earnings Per Share - Additional Information (Details) (USD $)	15 Months Ended	3 Months Ended
In Millions, except Share data in Thousands, unless otherwise specified	Dec. 31, 2014	Apr. 03, 2015	Oct. 31, 2013
Computation Of Earnings Per Share Line Items
Repurchase of common stock	$0.50
Capital Stock
Computation Of Earnings Per Share Line Items
Shares repurchased	50	0
Maximum
Computation Of Earnings Per Share Line Items
Outstanding common stock repurchase program authorized amount			$10

Fair_Values_of_Financial_Asset

Fair Values of Financial Assets and Liabilities (Details) (USD $)	Apr. 03, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Assets
Cash equivalents	$722	$2,255
Total Assets	722
Liabilities
Contingent consideration	965
Total Liabilities	965
Fair Value, Inputs, Level 1
Assets
Cash equivalents	722	2,255
Total Assets	722
Fair Value, Inputs, Level 3
Liabilities
Contingent consideration	965
Total Liabilities	$965

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Details)	3 Months Ended
	Apr. 03, 2015
	Installment
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Business combination, date of agreement	19-Feb-15
Number of contingent consideration installments	2
Minimum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Date for achieving revenue target	31-Dec-15
Contingent consideration payment year	2017
Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Date for achieving revenue target	31-Dec-17
Contingent consideration payment year	2018

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets - Additional Information (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014
Goodwill And Intangible Assets Disclosure [Abstract]
Impairment Charge, Goodwill	$19.60

Summary_of_Changes_in_Goodwill

Summary of Changes in Goodwill (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Apr. 03, 2015
Goodwill And Intangible Assets Disclosure [Abstract]
Balance at beginning of the period	$90,746
Goodwill acquired from the Applimotion acquisition	7,553
Balance at end of the period	$98,299

Goodwill_By_Reportable_Segment

Goodwill By Reportable Segment (Details) (USD $)	Apr. 03, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Goodwill [Line Items]
Goodwill	$249,528	$241,975
Accumulated impairment of goodwill	-151,229	-151,229
Total	98,299	90,746
Laser Products
Goodwill [Line Items]
Goodwill	132,954	132,954
Accumulated impairment of goodwill	-102,461	-102,461
Total	30,493	30,493
Medical Technologies
Goodwill [Line Items]
Goodwill	82,730	82,730
Accumulated impairment of goodwill	-31,722	-31,722
Total	51,008	51,008
Precision Motion
Goodwill [Line Items]
Goodwill	33,844	26,291
Accumulated impairment of goodwill	-17,046	-17,046
Total	$16,798	$9,245

Intangible_Assets_Details

Intangible Assets (Details) (USD $)	Apr. 03, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Schedule of Intangible Assets Disclosure [Line Items]
Amortizable intangible assets, gross carrying amount	$160,601	$155,127
Amortizable intangible assets, accumulated amortization	-103,344	-100,912
Amortizable intangible assets, net carrying amount	57,257	54,215
Non-amortizable intangible assets	13,027	13,027
Gross carrying amount	173,628	168,154
Net carrying amount	70,284	67,242
Patents and acquired technology
Schedule of Intangible Assets Disclosure [Line Items]
Amortizable intangible assets, gross carrying amount	80,538	78,253
Amortizable intangible assets, accumulated amortization	-62,730	-62,010
Amortizable intangible assets, net carrying amount	17,808	16,243
Customer Relationships
Schedule of Intangible Assets Disclosure [Line Items]
Amortizable intangible assets, gross carrying amount	64,977	63,029
Amortizable intangible assets, accumulated amortization	-32,772	-31,531
Amortizable intangible assets, net carrying amount	32,205	31,498
Customer Backlog
Schedule of Intangible Assets Disclosure [Line Items]
Amortizable intangible assets, gross carrying amount	2,447	1,810
Amortizable intangible assets, accumulated amortization	-1,901	-1,641
Amortizable intangible assets, net carrying amount	546	169
Non-compete Covenant
Schedule of Intangible Assets Disclosure [Line Items]
Amortizable intangible assets, gross carrying amount	2,514	1,830
Amortizable intangible assets, accumulated amortization	-479	-366
Amortizable intangible assets, net carrying amount	2,035	1,464
Trademarks and Trade Names
Schedule of Intangible Assets Disclosure [Line Items]
Amortizable intangible assets, gross carrying amount	10,125	10,205
Amortizable intangible assets, accumulated amortization	-5,462	-5,364
Amortizable intangible assets, net carrying amount	$4,663	$4,841

Amortization_Expense_of_Intang

Amortization Expense of Intangible Assets (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Apr. 03, 2015	Mar. 28, 2014
Goodwill And Intangible Assets Disclosure [Abstract]
Amortization expense – cost of sales	$1,119	$1,301
Amortization expense – operating expenses	1,889	1,744
Total amortization expense	$3,008	$3,045

Estimated_Amortization_Expense

Estimated Amortization Expense (Details) (USD $)	Apr. 03, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Finite-Lived Intangible Assets [Line Items]
2015 (remainder of year)	$9,076
2016	10,803
2017	9,861
2018	7,752
2019	5,495
Thereafter	14,270
Amortizable intangible assets, net carrying amount	57,257	54,215
Cost of Sales
Finite-Lived Intangible Assets [Line Items]
2015 (remainder of year)	3,524
2016	3,550
2017	3,229
2018	1,754
2019	1,487
Thereafter	4,264
Amortizable intangible assets, net carrying amount	17,808
Operating Expense
Finite-Lived Intangible Assets [Line Items]
2015 (remainder of year)	5,552
2016	7,253
2017	6,632
2018	5,998
2019	4,008
Thereafter	10,006
Amortizable intangible assets, net carrying amount	$39,449

Inventories_Details

Inventories (Details) (USD $)	Apr. 03, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Inventory Disclosure [Abstract]
Raw materials	$37,444	$38,934
Work-in-process	10,293	9,899
Finished goods	11,551	11,945
Demo and consigned inventory	1,394	2,165
Total inventories	$60,682	$62,943

Accrued_Expenses_and_Other_Cur

Accrued Expenses and Other Current Liabilities (Details) (USD $)	Apr. 03, 2015	Dec. 31, 2014	Mar. 28, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Other Liabilities Disclosure [Abstract]
Accrued compensation and benefits	$8,269	$7,741
Accrued warranty	2,825	3,044	3,310	3,315
Accrued professional services	2,201	1,827
Other	8,229	6,789
Total	$21,524	$19,401

Accrued_Warranty_Details

Accrued Warranty (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Apr. 03, 2015	Mar. 28, 2014
Product Warranties Disclosures [Abstract]
Balance at beginning of the period	$3,044	$3,315
Provision charged to cost of sales	429	481
Acquisition related warranty accrual	94	90
Use of provision	-342	-571
Reclassification to liabilities held for sale	-376
Foreign currency exchange rate changes	-24	-5
Balance at end of period	$2,825	$3,310

Summary_of_Other_Long_Term_Lia

Summary of Other Long Term Liabilities (Details) (USD $)	Apr. 03, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Other Liabilities Noncurrent [Abstract]
Capital lease obligations	$9,458	$9,507
Accrued pension liabilities	5,409	6,037
Other	3,828	3,275
Total	$18,695	$18,819

Debt_Details

Debt (Details) (USD $)	Apr. 03, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Debt Instrument [Line Items]
Senior Credit Facilities	$123,125	$115,000
Senior Credit Facilities	115,625	107,500
Term Loans
Debt Instrument [Line Items]
Senior Credit Facilities	33,125	35,000
Revolving Credit Facility
Debt Instrument [Line Items]
Senior Credit Facilities	$90,000	$80,000

Debt_Additional_Information_De

Debt - Additional Information (Details) (USD $)	3 Months Ended
	Apr. 03, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Quarterly installments payable on term loan	$1,900,000
Current portion of long-term debt	7,500,000	7,500,000
Revolving credit facility maturity year	2017-12
Term Loans
Debt Instrument [Line Items]
Maximum borrowing capacity	50,000,000
Debt instrument maturity period	5 years
Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$175,000,000
Debt instrument maturity period	5 years

Restricted_Stock_Units_Issued_

Restricted Stock Units Issued and Outstanding (Details) (2010 Incentive Award Plan, Restricted Stock Units (RSUs), USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Apr. 03, 2015
2010 Incentive Award Plan | Restricted Stock Units (RSUs)
Restricted Stock Units
Unvested, Beginning Balance	749
Granted	287
Vested	-294
Forfeited	-27
Unvested, Ending Balance	715
Expected to vest at end of period	691
Weighted Average Grant Date Fair Value
Unvested, Beginning Balance	$10.80
Granted	$13.29
Vested	$11.10
Forfeited	$11.03
Unvested, Ending Balance	$11.67

ShareBased_Compensation_Additi

Share-Based Compensation - Additional Information (Details) (USD $)	3 Months Ended		0 Months Ended	12 Months Ended
	Apr. 03, 2015	Mar. 28, 2014	Mar. 14, 2014	Dec. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense recognized	$1,553,000	$1,485,000
JADAK Acquisition
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Membership interests acquired			100.00%
Restricted Stock Units (RSUs) | JADAK Acquisition | Management
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units issued			180,000
Vesting period			2 years
Shares forfeited	90,000			45,000
Number of owner managers	2
Deferred Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense recognized	500,000	500,000
2010 Incentive Award Plan | Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total fair value of restricted stock vested	$3,700,000
Shares forfeited	27,000

Share_Based_Compensation_Expen

Share Based Compensation Expense Recorded In Income from Continuing Operations in Statements of Operations (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Apr. 03, 2015	Mar. 28, 2014
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	$1,553	$1,485
Selling, general and administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	1,484	1,356
Research and development and engineering
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	49	50
Cost of Sales
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	64	33
Restructuring, acquisition and divestiture related costs
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	($44)	$46

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Details)	3 Months Ended
	Apr. 03, 2015	Mar. 28, 2014
Income Taxes [Line Items]
Effective tax rate on income from operations	34.30%	24.70%
CANADA
Income Taxes [Line Items]
Statutory tax rate	27.00%

Schedule_of_Restructuring_Acqu

Schedule of Restructuring, Acquisition and Divestiture Related Costs (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Apr. 03, 2015	Mar. 28, 2014
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$1,753	$28
Acquisition and divestiture related charges	684	790
Restructuring, acquisition and divestiture related costs	2,437	818
JADAK Acquisition | Earn-out Agreement
Restructuring Cost And Reserve [Line Items]
Recognized acquisition costs	-80	87
Acquisition Charges
Restructuring Cost And Reserve [Line Items]
Recognized acquisition costs	207	703
2011 Restructuring
Restructuring Cost And Reserve [Line Items]
Restructuring charges	383	28
2015 Restructuring
Restructuring Cost And Reserve [Line Items]
Restructuring charges	1,370
JK Laser Divesture Charges
Restructuring Cost And Reserve [Line Items]
JK Lasers divestiture related charges	$557

Restructuring_Acquisition_and_2

Restructuring, Acquisition and Divestiture Related Costs - Additional Information (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Apr. 03, 2015
2011 Restructuring
Restructuring Cost And Reserve [Line Items]
Restructuring plan	In November 2011, the Company announced a strategic initiative (“2011 restructuring”), which aimed to consolidate operations to reduce the Company’s cost structure and improve operational efficiency. As part of this initiative, the Company eliminated facilities through the consolidation of certain manufacturing, sales and distribution facilities and the exit of Semiconductor and Laser Systems businesses. The Company substantially completed the 2011 restructuring program by the end of 2013. Restructuring costs for the three months ended April 3, 2015 included facility costs of $0.4 million related to the Company’s vacant Orlando, Florida facility, which the Company owns and was previously occupied by the Laser Systems business. These costs were recorded in the Corporate, Shared Services and Unallocated segment.
Facility costs, Orlando, Florida facility	$0.40
2015 Restructuring
Restructuring Cost And Reserve [Line Items]
Restructuring plan	During the first quarter of 2015, the Company initiated a program to eliminate redundant costs, as a result of acquisition and divestiture activities, to better align our operations to our strategic growth plans, to further integrate our business lines, and as a consequence of our productivity initiatives. During the three months ended April 3, 2015, the Company incurred $1.3 million in severance costs related to the 2015 restructuring. Restructuring costs of $0.6 million, $0.4 million, $0.1 million and $0.3 million related to the Laser Products, Medical Technologies, Precision Motion and Corporate, Shared Services and Unallocated reportable segments, respectively.
Severance costs	1.3
2015 Restructuring | Medical Technologies
Restructuring Cost And Reserve [Line Items]
Restructuring Costs	0.4
2015 Restructuring | Precision Motion
Restructuring Cost And Reserve [Line Items]
Restructuring Costs	0.1
2015 Restructuring | Corporate, Shared Services and Unallocated
Restructuring Cost And Reserve [Line Items]
Restructuring Costs	0.3
2015 Restructuring | Laser Products
Restructuring Cost And Reserve [Line Items]
Restructuring Costs	$0.60

Summary_of_Accrual_Activities_

Summary of Accrual Activities by Components Related to Company's Restructuring Charges (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Apr. 03, 2015	Mar. 28, 2014
Restructuring Cost And Reserve [Line Items]
Accrued expense beginning balance	$231
Restructuring charges	1,753	28
Cash payments	-542
Non-cash write-offs and other adjustments	-328
Accrued expense ending balance	1,114
Employee Severance
Restructuring Cost And Reserve [Line Items]
Accrued expense beginning balance	102
Restructuring charges	1,328
Cash payments	-366
Non-cash write-offs and other adjustments	4
Accrued expense ending balance	1,068
Facility
Restructuring Cost And Reserve [Line Items]
Accrued expense beginning balance	105
Restructuring charges	58
Cash payments	-130
Accrued expense ending balance	33
Depreciation
Restructuring Cost And Reserve [Line Items]
Restructuring charges	332
Non-cash write-offs and other adjustments	-332
Other Restructuring Charges
Restructuring Cost And Reserve [Line Items]
Accrued expense beginning balance	24
Restructuring charges	35
Cash payments	-46
Accrued expense ending balance	$13

Segment_Information_Additional

Segment Information - Additional Information (Details)	3 Months Ended
	Apr. 03, 2015
	Segment
Segment Reporting [Abstract]
Number of reportable segments	3

Sales_Gross_Profit_and_Gross_P

Sales, Gross Profit and Gross Profit Margin by Reportable Segments (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Apr. 03, 2015	Mar. 28, 2014
Segment Reporting Information [Line Items]
Sales	$94,614	$79,133
Gross Profit	40,006	32,105
Gross profit margin percentage	42.30%	40.60%
Laser Products
Segment Reporting Information [Line Items]
Sales	44,955	41,860
Gross Profit	19,375	17,013
Gross profit margin percentage	43.10%	40.60%
Medical Technologies
Segment Reporting Information [Line Items]
Sales	31,111	22,367
Gross Profit	12,513	8,889
Gross profit margin percentage	40.20%	39.70%
Precision Motion
Segment Reporting Information [Line Items]
Sales	18,548	14,906
Gross Profit	8,465	6,416
Gross profit margin percentage	45.60%	43.00%
Corporate, Shared Services and Unallocated
Segment Reporting Information [Line Items]
Gross Profit	($347)	($213)

Operating_Income_Loss_from_Con

Operating Income (Loss) from Continuing Operations by Reportable Segments (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Apr. 03, 2015	Mar. 28, 2014
Operating Income (Loss) from Continuing Operations
Operating Income (Loss) from Continuing Operations	$5,397	$4,068
Laser Products
Operating Income (Loss) from Continuing Operations
Operating Income (Loss) from Continuing Operations	8,395	7,124
Medical Technologies
Operating Income (Loss) from Continuing Operations
Operating Income (Loss) from Continuing Operations	-654	-117
Precision Motion
Operating Income (Loss) from Continuing Operations
Operating Income (Loss) from Continuing Operations	4,137	2,643
Corporate, Shared Services and Unallocated
Operating Income (Loss) from Continuing Operations
Operating Income (Loss) from Continuing Operations	($6,481)	($5,582)

Depreciation_and_Amortization_

Depreciation and Amortization by Reportable Segments (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Apr. 03, 2015	Mar. 28, 2014
Depreciation and Amortization
Depreciation and Amortization	$4,762	$4,829
Laser Products
Depreciation and Amortization
Depreciation and Amortization	1,582	1,666
Medical Technologies
Depreciation and Amortization
Depreciation and Amortization	2,258	2,091
Precision Motion
Depreciation and Amortization
Depreciation and Amortization	473	502
Corporate, Shared Services and Unallocated
Depreciation and Amortization
Depreciation and Amortization	$449	$570