Nature of Operations and Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jul. 01, 2017
Accounting Policies [Abstract]
Critical Accounting Policies	Critical Accounting Policies Critical accounting policies are defined as those that entail significant judgments and estimates, and could potentially result in materially different results under different assumptions and conditions. The Company believes that the most critical accounting policies upon which its financial position depends, and which involve the most complex or subjective decisions or assessments, concern revenue recognition and accounts receivable, warranty obligations, income taxes, the valuation of goodwill and intangible assets, inventories and pension obligations. A discussion of the application of these and other accounting policies is included in Notes 1 and 3 to the consolidated financial statements in the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2016.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (GAAP) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Although the Company makes every effort to ensure the accuracy of the estimates and assumptions used in the preparation of its condensed consolidated financial statements or in the application of accounting policies, if business conditions were different, or if the Company were to use different estimates and assumptions, it is possible that materially different amounts could be reported in the Company's condensed consolidated financial statements.
Restricted Cash	Restricted Cash As of July 1, 2017 and December 31, 2016, the Company had restricted cash of $2,141,000 and $2,082,000, respectively. This cash serves as collateral for bank guarantees primarily associated with providing assurance to customers that the Company will fulfill certain customer obligations entered into in the normal course of business. The majority of the bank guarantees will expire by the end of 2018.
Banker's Acceptance Drafts	Banker's Acceptance Drafts The Company's Chinese subsidiaries may receive banker's acceptance drafts from customers as payment for their trade accounts receivable. The banker's acceptance drafts are non-interest bearing obligations of the issuing bank and mature within six months of the origination date. The Company can sell the drafts at a discount to a third-party financial institution or transfer the drafts to vendors in settlement of current accounts payable prior to the scheduled maturity date. These drafts, which totaled $10,181,000 and $7,852,000 at July 1, 2017 and December 31, 2016, respectively, are included in accounts receivable in the accompanying condensed consolidated balance sheet until the subsidiary sells the drafts to a bank and receives a discounted amount, transfers the banker's acceptance drafts in settlement of current accounts payable prior to maturity, or obtains cash payment on the scheduled maturity date.
Warranty Obligations	Warranty Obligations The Company provides for the estimated cost of product warranties at the time of sale based on the actual historical occurrence rates and repair costs, as well as knowledge of any specific warranty problems that indicate that projected warranty costs may vary from historical patterns. The Company typically negotiates the terms regarding warranty coverage and length of warranty depending on the products and applications. While the Company engages in extensive product quality programs and processes, the Company's warranty obligation is affected by product failure rates, repair costs, service delivery costs incurred in correcting a product failure, and supplier warranties on parts delivered to the Company. Should actual product failure rates, repair costs, service delivery costs, or supplier warranties on parts differ from the Company's estimates, revisions to the estimated warranty liability would be required.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Revenue from Contracts with Customers (Topic 606), Section A-Summary and Amendments That Create Revenue from Contracts with Customers (Topic 606) and Other Assets and Deferred Costs-Contracts with Customers (Subtopic 340-40). In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2014-09, which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The new guidance provides a five-step analysis of transactions to determine when and how revenue is recognized. The ASU will replace most existing revenue recognition guidance in GAAP when it becomes effective. In March 2016, the FASB issued ASU No. 2016-08, which further clarifies the guidance on the principal versus agent considerations within ASU No. 2014-09. In April 2016, the FASB issued ASU No. 2016-10 to expand the guidance on identifying performance obligations and licensing within ASU 2014-09. In May 2016, the FASB issued ASU No. 2016-11, which rescinds certain previously-issued guidance, including, among other items, guidance relating to accounting for shipping and handling fees and freight services effective upon adoption of ASU No. 2014-09. Also in May 2016, the FASB issued ASU No. 2016-12, which narrowly amended the revenue recognition guidance regarding collectability, noncash consideration, presentation of sales tax and transition. In December 2016, the FASB issued ASU No. 2016-20, which clarifies narrow aspects of Topic 606 and corrects unintended application of the guidance. These new ASUs are effective for the Company beginning in fiscal 2018. Early adoption is permitted in fiscal 2017. The Company is continuing to assess the potential effects of these ASUs on its condensed consolidated financial statements, business processes, systems and controls. While the assessment process is ongoing, the Company currently anticipates adopting these ASUs using the modified retrospective transition approach. Under this approach, this guidance would apply to all new contracts initiated in fiscal 2018. For existing contracts that have remaining obligations as of the beginning of fiscal 2018, any difference between the recognition criteria in these ASUs and the Company’s current revenue recognition practices would be recognized using a cumulative effect adjustment to the opening balance of retained earnings. The Company is also in the process of developing and implementing appropriate changes to its business processes, systems and controls to support the recognition criteria and disclosure requirements of these ASUs. Inventory (Topic 330), Simplifying the Measurement of Inventory. In July 2015, the FASB issued ASU No. 2015-11, which requires that an entity measure inventory within the scope of this ASU at the lower of cost or net realizable value. Net realizable value is the estimated selling price in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. Substantial and unusual losses that result from subsequent measurement of inventory should be disclosed in the financial statements. The Company adopted this ASU at the beginning of fiscal 2017. Adoption of this ASU did not have a material effect on the Company's condensed consolidated financial statements. Leases (Topic 842). In February 2016, the FASB issued ASU No. 2016-02, which requires a lessee to recognize a right-of-use asset and a lease liability for operating leases, initially measured at the present value of the future lease payments, in its balance sheet. This ASU also requires a lessee to recognize a single lease cost, calculated so that the cost of the lease is allocated over the lease term, generally on a straight-line basis. This new guidance is effective for the Company in fiscal 2019. Early adoption is permitted. As part of the implementation of this new standard, the Company is in the process of reviewing current accounting policies and assessing the practical expedients allowed under this new guidance. The Company expects that most of its operating lease commitments will be subject to the new standard and recognized as operating lease liabilities and right-of-use assets upon adoption, which is required using the modified retrospective transition method. The Company is currently evaluating the other effects that the adoption of this ASU will have on its condensed consolidated financial statements. Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments. In June 2016, the FASB issued ASU No. 2016-13, which significantly changes the way entities recognize impairment of many financial assets by requiring immediate recognition of estimated credit losses expected to occur over their remaining lives. This new guidance is effective for the Company in fiscal 2020. Early adoption is permitted beginning in fiscal 2019. The Company is currently evaluating the effects that the adoption of this ASU will have on its condensed consolidated financial statements. Statement of Cash Flows (Topic 230), Classification of Certain Cash Receipts and Cash Payments. In August 2016, the FASB issued ASU No. 2016-15, which simplifies the diversity in practice related to the presentation and classification of certain cash receipts and cash payments in the statement of cash flows under Topic 230. This ASU addresses the following eight specific cash flow issues: debt prepayment or debt extinguishment costs; settlement of zero-coupon debt instruments or other debt instruments with coupon interest rates that are insignificant in relation to the effective interest rate of the borrowing; contingent consideration payments made after a business combination; proceeds from the settlement of insurance claims; proceeds from the settlement of corporate-owned life insurance; distributions received from equity method investees; beneficial interests in securitization transactions; and separately identifiable cash flows and application of the predominance principle. This new guidance is effective for the Company in fiscal 2018. Early adoption is permitted. The Company does not believe that adoption of this ASU will have a material impact on its condensed consolidated financial statements. Income Taxes (Topic 740), Intra-Entity Transfers of Assets Other Than Inventory. In October 2016, the FASB issued ASU No. 2016-16, which requires an entity to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs and eliminates the exception for an intra-entity transfer of an asset other than inventory. This new guidance is effective for the Company in fiscal 2018 with adoption required on a modified retrospective basis through a cumulative-effect adjustment directly to retained earnings as of the beginning of the period of adoption. Early adoption is permitted. The Company is currently evaluating the effect that the adoption of this ASU will have on its condensed consolidated financial statements. Statement of Cash Flows (Topic 230), Restricted Cash. In November 2016, the FASB issued ASU No. 2016-18, which requires inclusion of restricted cash and restricted cash equivalents within cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. This new guidance is effective for the Company in fiscal 2018. Early adoption is permitted. As this ASU is presentation-related only, adoption of this ASU will not have a material impact on the Company's condensed consolidated financial statements. Business Combinations (Topic 805), Clarifying the Definition of a Business. In January 2017, the FASB issued ASU No. 2017-01, which clarifies the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The revised definition of a business under this ASU will reduce the number of transactions that are accounted for as business combinations. This new guidance is effective on a prospective basis for the Company in fiscal 2018. Early adoption is allowed for certain transactions. The Company is currently evaluating the effects that the adoption of this ASU will have on its condensed consolidated financial statements. Intangibles - Goodwill and Other (Topic 350), Simplifying the Test for Goodwill Impairment. In January 2017, the FASB issued ASU No. 2017-04, which eliminates Step 2 in goodwill impairment testing, which requires that goodwill impairment losses be measured as the difference between the implied value of a reporting unit’s goodwill and its carrying amount. This ASU will reduce the cost and complexity of impairment testing by requiring goodwill impairment losses to be measured as the excess of the reporting unit’s carrying amount, including goodwill and related goodwill tax effects, over its fair value. This new guidance is effective on a prospective basis for the Company in fiscal 2020. Early adoption is permitted. The Company does not believe that adoption of this ASU will have a material effect on its condensed consolidated financial statements. Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Post-retirement Benefit Cost. In March 2017, the FASB issued ASU No. 2017-07, which requires employers to include only the service cost component of net periodic pension cost and net periodic post-retirement benefit cost in operating expenses in the same income statement line item as the related employees' compensation costs. The other components of net benefit cost, including interest costs, amortization of prior service costs and settlement and curtailment effects, are to be included in non-operating expenses. The ASU also stipulates that only the service cost component of net benefit cost is eligible for capitalization. This new guidance is effective on a retrospective basis for the Company in fiscal 2018. Early adoption is permitted. The Company is currently evaluating the effects that adoption of this ASU will have on its condensed consolidated financial statements. Compensation - Stock Compensation (Topic 718): Scope of Modification Accounting. In May 2017, the FASB issued ASU No. 2017-09, which provides clarity on which changes to the terms or conditions of share-based payment awards require entities to apply the modification accounting provisions required in Topic 718. This new guidance is effective on a prospective basis for the Company in fiscal 2018. Early adoption is permitted. The Company does not believe that adoption of this ASU will have a material effect on its condensed consolidated financial statements.
Derivatives	The Company uses derivative instruments primarily to reduce its exposure to changes in currency exchange rates and interest rates. When the Company enters into a derivative contract, the Company makes a determination as to whether the transaction is deemed to be a hedge for accounting purposes. For a contract deemed to be a hedge, the Company formally documents the relationship between the derivative instrument and the risk being hedged. In this documentation, the Company specifically identifies the asset, liability, forecasted transaction, cash flow, or net investment that has been designated as the hedged item, and evaluates whether the derivative instrument is expected to reduce the risks associated with the hedged item. To the extent these criteria are not met, the Company does not use hedge accounting for the derivative. The changes in the fair value of a derivative not deemed to be a hedge are recorded currently in earnings. The Company does not hold or engage in transactions involving derivative instruments for purposes other than risk management. Accounting Standards Codification (ASC) 815, Derivatives and Hedging, requires that all derivatives be recognized in the accompanying condensed consolidated balance sheet at fair value. For derivatives designated as cash flow hedges, the related gains or losses on these contracts are deferred as a component of AOCI. These deferred gains and losses are recognized in the accompanying condensed consolidated statement of income in the period in which the underlying anticipated transaction occurs. For derivatives designated as fair value hedges, the unrealized gains and losses resulting from the impact of currency exchange rate movements are recognized in earnings in the period in which the exchange rates change and offset the currency gains and losses on the underlying exposures being hedged. The Company performs an evaluation of the effectiveness of the hedge both at inception and on an ongoing basis. The ineffective portion of a hedge, if any, and changes in the fair value of a derivative not deemed to be a hedge are recorded in the accompanying condensed consolidated statement of income.
Fair Value Measurement	The carrying values of the Company's revolving credit facility and capital lease obligations approximate fair value as the obligations bear variable rates of interest, which adjust quarterly based on prevailing market rates. The Company uses the market approach technique to value its financial assets and liabilities, and there were no changes in valuation techniques during the first six months of 2017. The Company's financial assets and liabilities carried at fair value are comprised of cash equivalents, banker's acceptance drafts, and derivative instruments used to hedge the Company's foreign currency and interest rate risks. The Company's cash equivalents are comprised of money market funds and bank deposits which are highly liquid and readily tradable. These cash equivalents are valued using inputs observable in active markets for identical securities. The carrying value of banker's acceptance drafts approximates their fair value due to the short-term nature of the negotiable instrument. The fair value of the Company's interest rate swap agreement is based on LIBOR yield curves at the reporting date. The fair values of the Company's forward currency-exchange contracts are based on quoted forward foreign exchange rates at the reporting date or acquisition date spot rates. The forward currency-exchange contracts and interest rate swap agreement are hedges of either recorded assets or liabilities or anticipated transactions. Changes in values of the underlying hedged assets and liabilities or anticipated transactions are not reflected in the table above.