Advanced Energy Industries (AEIS) 10-Q 30 Apr 18 2018 Q1 Quarterly report Financial data

Document and Enitity Informatio

Document and Enitity Information - shares	3 Months Ended
	Mar. 31, 2018	Apr. 26, 2018
Document Entity Information [Abstract]
Entity Registrant Name	ADVANCED ENERGY INDUSTRIES INC
Entity Central Index Key	927,003
Document Type	10-Q
Document Period End Date	Mar. 31, 2018
Amendment Flag	false
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		39,329,426

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
CURRENT ASSETS:
Cash and cash equivalents	$ 413,874	$ 407,283
Marketable securities	3,197	3,104
Accounts and other receivable, net of allowances of $1,824 and $1,748 respectively	116,900	87,429
Inventories	96,842	78,450
Income taxes receivable	2,226	1,295
Other current assets	7,895	8,129
Current assets from discontinued operations	9,638	9,535
Total current assets	650,572	595,225
Deposits and other assets	4,207	3,051
Property and equipment, net	20,706	17,795
Goodwill	54,906	53,812
Finite-Lived Intangible Assets, Net	33,445	33,499
Deferred income tax assets	38,741	18,841
Non-current assets from discontinued operations	11,084	11,085
TOTAL ASSETS	813,661	733,308
CURRENT LIABILITIES:
Accounts payable	61,328	48,177
Income taxes payable	13,011	5,365
Accrued payroll and employee benefits	13,890	18,412
Customer deposits	9,738	6,402
Other accrued expenses	21,395	19,913
Current liabilities from discontinued operations	7,272	7,850
Total current liabilities	126,634	106,119
LONG-TERM LIABILITIES:
Deferred income tax liabilities	6,592	4,556
Uncertain tax positions	17,701	17,031
Long term deferred revenue	32,443	33,402
Other long-term liabilities	38,803	36,282
Non-current liabilities from discontinued operations	14,279	15,277
Total liabilities	236,452	212,667
STOCKHOLDERS' EQUITY:
Preferred stock, $0.001 par value, 1,000 shares authorized, none issued and outstanding	0	0
Common stock, $0.001 par value, 70,000 shares authorized; 39,536 and 39,604 issued and outstanding, respectively	40	40
Additional paid-in capital	172,460	184,843
Retained earnings	399,410	333,225
Advanced Energy stockholders’ equity	4,837	2,533
Advanced Energy stockholders’ equity	576,747	520,641
Noncontrolling interest	462	0
Total stockholders’ equity	577,209	520,641
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 813,661	$ 733,308

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets Parenthetical - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Accounts receivable, allowances	$ 1,824	$ 1,748
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	1,000	1,000
Preferred stock, shares issued (in shares)	0
Preferred Stock, Shares Outstanding	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	70,000,000	70,000,000
Common stock, shares issued (in shares)	39,535,000	39,604,000
Common stock, shares outstanding (in shares)	39,535,000	39,604,000

Condensed Consolidated Statemen

Condensed Consolidated Statement of Operations Statement - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Sales:
Product	$ 171,209	$ 128,827
Services	24,408	20,524
Total sales	195,617	149,351
Cost of sales:
Product	79,806	60,117
Services	12,166	10,403
Total cost of sales	91,972	70,520
Gross profit	103,645	78,831
Operating expenses:
Research and development	17,637	12,503
Selling, general and administrative	28,648	22,098
Amortization of intangible assets	1,257	962
Total operating expenses	47,542	35,563
Operating income	56,103	43,268
Other income (expense), net	26	(3,208)
Income from continuing operations, before income taxes	56,129	40,060
Provision for income taxes	9,759	4,619
Income from continuing operations	46,370	35,441
Income from discontinued operations, net of income taxes	140	2,094
Net income	46,510	37,535
Income from continuing operations attributable to noncontrolling interest	31	0
Net income attributable to Advanced Energy Industries, Inc.	$ 46,479	$ 37,535
Basic weighted-average common shares outstanding	39,619	39,738
Diluted weighted-average common shares outstanding	39,995	40,179
Income (Loss) from Continuing Operations, Per Basic Share	$ 1.17	$ 0.89
Income (Loss) from Continuing Operations, Per Diluted Share	1.16	0.88
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share	0	0.05
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share	0	0.05
Earnings Per Share, Basic	1.17	0.94
Earnings Per Share, Diluted	$ 1.16	$ 0.93

Condensed Consolidated Stateme5

Condensed Consolidated Statement of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 46,510	$ 37,535
Net Income (Loss) Attributable to Parent	46,479	37,535
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	2,472	3,028
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment, after Tax	168	16
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	48,814	40,547
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	31	0
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 48,783	$ 40,547

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 46,510	$ 37,535
CASH FLOWS FROM OPERATING ACTIVITIES:
Income from discontinued operations, net of income taxes	140	2,094
Income from continuing operations, net of income taxes	46,370	35,441
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	2,861	1,987
Stock-based compensation expense	4,494	3,398
Loss on foreign exchange hedge	0	3,489
Net loss on disposal of assets	(138)	(65)
Changes in operating assets and liabilities, net of assets acquired:
Accounts and other receivables	(17,457)	(431)
Inventories	(17,113)	(8,047)
Other current assets	364	(1,109)
Accounts payable	11,932	5,194
Other liabilities and accrued expenses	(2,346)	(614)
Income taxes	5,642	3,286
Net cash provided by operating activities from continuing operations	34,885	42,659
Net cash used in operating activities from discontinued operations	(1,784)	(2,453)
Net cash provided by operating activities	33,101	40,206
CASH FLOWS FROM INVESTING ACTIVITIES:
Acquisition, net of cash acquired	(6,072)	0
Purchase of foreign exchange hedge	0	(3,489)
Purchases of property and equipment	(3,923)	(1,391)
Net cash used in investing activities from continuing operations	(9,995)	(4,880)
Net cash used in investing activities from discontinued operations	0	0
Net cash used in investing activities	(9,995)	(4,880)
CASH FLOWS FROM FINANCING ACTIVITIES:
Purchase and retirement of common stock	12,750	0
Net payments related to stock-based award activities	(4,032)	(1,688)
Net cash used in financing activities from continuing operations	(16,782)	(1,688)
Net cash used in financing activities from discontinued operations	0	0
Net cash used in financing activities	(16,782)	(1,688)
EFFECT OF CURRENCY TRANSLATION ON CASH	167	1,133
INCREASE IN CASH AND CASH EQUIVALENTS	6,491	34,771
CASH AND CASH EQUIVALENTS, beginning of period	415,037	289,517
CASH AND CASH EQUIVALENTS, end of period	421,528	324,288
Less cash and cash equivalents from discontinued operations	7,654	6,339
CASH AND CASH EQUIVALENTS FROM CONTINUING OPERATIONS, end of period	413,874	317,949
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash paid for interest	56	0
Cash paid for income taxes	3,404	918
Cash received for refunds of income taxes	95	396
Cash held in banks outside the United States	$ 320,753	$ 239,553

Operations and Summary of Signi

Operations and Summary of Significant Accounting Policies and Estimates	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Basis of Presentation	BASIS OF PRESENTATION Advanced Energy Industries, Inc., a Delaware corporation, and its wholly-owned subsidiaries ("we," "us," "our," "Advanced Energy," or the "Company") design, manufacture, sell, and support power conversion products that transform electrical power into various usable forms. Our products enable manufacturing processes that use thin films for various products, such as semiconductor devices, flat panel displays, solar cells, architectural glass, optical coating and decorative and functional coating for consumer products. We also supply thermal instrumentation products for advanced temperature control in the thin film process for these same markets. Our power control modules provide power control solutions for industrial applications where heat treatment and processing are used such as glass manufacturing, metal fabrication and treatment, and material and chemical processing. Our high voltage power supplies and modules are used in applications such as semiconductor ion implantation, scanning electron microscopy, chemical analysis such as mass spectrometry and various applications using X-ray technology and electron guns for both analytical and processing applications. Our network of global service support centers provides a recurring revenue opportunity as we offer repair services, conversions, upgrades, and refurbishments and sales of used equipment to companies using our products. As of December 31, 2015, we discontinued the production, engineering, and sales of our solar inverter product line. As such, all solar inverter revenues, costs, assets and liabilities are reported in Discontinued Operations for all periods presented herein. See Note 4. Discontinued Operations. In the opinion of management, the accompanying Unaudited Condensed Consolidated Financial Statements contain all adjustments, consisting of normal, recurring adjustments, necessary to present fairly the financial position of the Company as of March 31, 2018 , and the results of our operations and cash flows for the three months ended March 31, 2018 and 2017 . The Unaudited Condensed Consolidated Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission ("SEC"). Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") have been condensed or omitted pursuant to such rules and regulations. These Unaudited Condensed Consolidated Financial Statements should be read in conjunction with the audited Consolidated Financial Statements and Notes thereto contained in our Annual Report on Form 10-K for the fiscal year ended December 31, 2017 and other financial information filed with the SEC. Estimates and Assumptions The preparation of our Unaudited Condensed Consolidated Financial Statements in conformity with U.S. GAAP requires us to make estimates, assumptions and judgments that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. We believe that the significant estimates, assumptions, and judgments when accounting for items and matters such as allowances for doubtful accounts, excess and obsolete inventory, warranty reserves, acquisitions, asset valuations, goodwill, asset life, depreciation, amortization, recoverability of assets, impairments, deferred revenue, stock option and restricted stock grants, taxes, and other provisions are reasonable, based upon information available at the time they are made. Actual results may differ from these estimates. Critical Accounting Policies Our accounting policies are described in our audited Consolidated Financial Statements and Notes contained in our Annual Report on Form 10-K for the year ended December 31, 2017 . See Note 3. Revenue for the updated revenue recognition policy in accordance with ASU 2014-09, "Revenue from Contracts with Customers". New Accounting Standards From time to time, the Financial Accounting Standards Board ("FASB") or other standards setting bodies issue new accounting pronouncements. Updates to the FASB Accounting Standards Codification ("ASC") are communicated through issuance of an Accounting Standards Update ("ASU"). Unless otherwise discussed, we believe that the impact of recently issued guidance, whether adopted or to be adopted in the future, is not expected to have a material impact on the Consolidated Financial Statements upon adoption. Recently issued accounting pronouncements not yet adopted In February 2016, the FASB issued ASU 2016-02, "Leases (Topic 842)," to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018, including interim periods within the year of adoption. Early adoption is permitted. Advanced Energy is currently assessing and has not yet determined the impact ASU 2016-02 may have on its Consolidated Financial Statements. In February 2018, the FASB issued ASU 2018-02, "Income Statement—Reporting Comprehensive Income" to give companies the option to reclassify the income tax effects on items within accumulated other comprehensive income resulting from U.S. tax reform to retained earnings. ASU 2018-02 is effective for fiscal years beginning after December 15, 2018, including interim periods within those years. Early adoption is permitted. Advanced Energy is currently assessing and has not yet determined the impact ASU 2018-02 may have on its Consolidated Financial Statements. Recently adopted accounting pronouncements In May 2014, the FASB issued ASU 2014-09, "Revenue from Contracts with Customers" and has subsequently issued several supplemental and/or clarifying ASUs (collectively known as "ASC 606"). ASC 606 implements a five step model for how an entity should recognize revenue in order to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASC 606 is effective for fiscal periods beginning after December 15, 2017 and for the interim periods within that year. We adopted ASC 606 during the first quarter of fiscal year 2018 using the modified retrospective approach and recorded an adjustment to reflect the cumulative-effect of its adoption on all contracts with customers. See Note 3. Revenue for further details. In October 2016, the FASB issued ASU 2016-16, "Accounting for Income Taxes: Intra-Entity Asset Transfers of Assets Other than Inventory." ASU 2016-16 changes the timing of income tax recognition for an intercompany sale of assets. ASU 2016-16 requires the seller’s tax effects and the buyer’s deferred taxes to be recognized immediately upon the sale instead of deferring accounting for the income tax implications until the assets are sold to a third party or recovered through use. ASU 2016-16 is effective for fiscal years beginning after December 15, 2017 including interim periods within the year of adoption. We adopted ASU 2016-16 during the first quarter of fiscal year 2018 using the modified retrospective approach and recorded a adjustment to reflect the cumulative-effect of its adoption. Cumulative-effect of recently adopted accounting pronouncements The following table reflects the cumulative-effect of the adoption of ASC 606 and ASU 2016-16 using the modified retrospective approach for: December 31, 2017 Impact of Impact of January 1, 2018 as reported ASC 606 ASU 2016-16 as adjusted Accounts and other receivable, net $ 87,429 $ 8,251 $ — $ 95,680 Inventories 78,450 (3,561 ) — 74,889 Total current assets 595,225 4,690 — 599,915 Deferred income tax assets 18,841 — 17,080 35,921 Total assets 733,308 4,690 17,080 755,078 Income taxes payable 5,365 — 921 6,286 Deferred income tax liabilities 4,556 1,143 — 5,699 Total liabilities 212,667 1,143 921 214,731 Retained earnings 333,225 3,547 16,159 352,931 Total stockholders’ equity 520,641 3,547 16,159 540,347 Total liabilities and stockholders' equity 733,308 4,690 17,080 755,078

Business Acquisition (Notes)

Business Acquisition (Notes)	3 Months Ended
	Mar. 31, 2018
Business Combinations [Abstract]
BUSINESS ACQUISITION	BUSINESS ACQUISITION On February 1, 2018, Advanced Energy acquired Trek Holding Co., LTD ("Trek"), a privately held company with operations in Tokyo, Japan and Lockport, New York. Trek has a 95% ownership interest in its U.S. subsidiary which is also its primary operation. The components of the fair value of the total consideration transferred for the Trek acquisition are as follows: Cash paid to owners $ 11,723 Cash acquired (5,651 ) Total fair value of consideration transferred $ 6,072 The following table summarizes estimated fair values of the assets acquired and liabilities assumed as of February 1, 2018: Accounts and other receivable, net $ 2,818 Inventories 4,037 Other current assets 275 Property and equipment 594 Other non-current assets 579 Deferred income tax assets 702 Accounts payable (747 ) Other accrued expenses (2,696 ) 5,562 Amortizable intangible assets: Technology 200 Customer relationships 200 Total amortizable intangible assets 400 Total identifiable net assets 5,962 Goodwill 110 Total fair value of consideration received $ 6,072 A summary of the intangible assets acquired, amortization method and estimated useful lives as of February 1, 2018 follows: Amount Amortization Method Useful Life Technology $ 200 Straight-line 10 Customer relationships 200 Straight-line 10 Total $ 400 Goodwill and intangible assets are recorded in the functional currency of the entity and are subject to changes due to translation at each balance sheet date. Advanced Energy is in the process of finalizing the assessment of fair value for the assets acquired and liabilities assumed.

Revenue (Notes)

Revenue (Notes)	3 Months Ended
	Mar. 31, 2018
Revenue [Abstract]
Revenue from Contract with Customer [Text Block]	REVENUE Adoption of ASC 606, "Revenue from Contract with Customers" Advanced Energy adopted ASC 606 using the modified retrospective method by recognizing the cumulative effect of the adoption of ASC 606, for all contracts with customers, to the opening balance of equity at January 1, 2018. Therefore, our comparative financial information as of December 31, 2017 has not been adjusted and continues to be reported under ASC Topic 605. The cumulative effect adjustment was based on the timing difference of revenue recognition between ASC Topic 605 and ASC 606 related to our inventory stocking agreements. Under ASC 606, revenue related to our inventory stocking agreements are recognized when inventory is shipped to our customers. Under ASC Topic 605, revenue was recognized when the inventory was consumed by our customers. The tables below show the quantitative impact of ASC 606 on our consolidated financial statements. March 31, 2018 Balances without adoption of As Reported Adjustments ASC 606 Accounts and other receivable, net $ 116,900 $ (9,710 ) $ 107,190 Inventories 96,842 4,086 100,928 Total current assets 650,572 (5,624 ) 644,948 TOTAL ASSETS 813,661 (5,624 ) 808,037 Income taxes payable 13,011 (230 ) 12,781 Total current liabilities 126,634 (230 ) 126,404 Deferred income tax liabilities 6,592 (1,143 ) 5,449 Total liabilities 236,452 (1,373 ) 235,079 Retained earnings 399,410 (4,251 ) 395,159 Advanced Energy stockholders’ equity 576,747 (4,251 ) 572,496 Total stockholders’ equity 577,209 (4,251 ) 572,958 TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY $ 813,661 $ (5,624 ) $ 808,037 Three Months Ended March 31, 2018 Balances without adoption of As Reported Adjustments ASC 606 Product sales $ 171,209 $ (1,460 ) $ 169,749 Total sales 195,617 (1,460 ) 194,157 Product cost of sales 79,806 (526 ) 79,280 Total cost of sales 91,972 (526 ) 91,446 Gross profit 103,645 (934 ) 102,711 Operating income 56,103 (934 ) 55,169 Income from continuing operations, before income taxes 56,129 (934 ) 55,195 Provision for income taxes 9,759 (230 ) 9,529 Income from continuing operations 46,370 (704 ) 45,666 Net income 46,510 (704 ) 45,806 Net income attributable to Advanced Energy Industries, Inc. $ 46,479 $ (704 ) $ 45,775 Three Months Ended March 31, 2018 Balances without adoption of As Reported Adjustments ASC 606 Net income $ 46,510 $ (704 ) $ 45,806 Changes in operating assets and liabilities, net of assets acquired: Accounts and other receivable, net (17,457 ) 1,460 (15,997 ) Inventories (17,113 ) (526 ) (17,639 ) Income taxes 5,642 (230 ) 5,412 Net cash provided by operating activities from continuing operations $ 34,885 $ — $ 34,885 Revenue Recognition We recognize revenue when we have satisfied our performance obligations which typically occurs when control of the products or services have been transfered to our customers. The transaction price is based upon the standalone selling price. In most transactions, we have no obligations to our customers after the date products are shipped, other than pursuant to warranty obligations. Shipping and handling fees billed to customers, if any, are recognized as revenue. The related shipping and handling costs are recognized in cost of sales. Support services include warranty and non-warranty repair services, upgrades, and refurbishments on the products we sell. Repairs that are covered under our standard warranty do not generate revenue. Practical Expedients We expense incremental costs of obtaining contracts when the amortization period of the costs are less then 1 year. These costs are included in selling, general, and administrative expenses. Nature of goods and services Products Advanced Energy provides highly-engineered, mission-critical, precision power conversion, measurement and control solutions to our global customers. We design, manufacture, sell and support precision power products that transform electrical power into various usable forms. Our power conversion products refine, modify and control the raw electrical power from a utility and convert it into power that is predictable, repeatable and customizable. Our products enable thin film manufacturing processes such as plasma enhanced chemical and physical deposition and etch for various semiconductor and industrial products, industrial thermal applications for material and chemical processes, and specialty power for critical industrial applications. We also supply thermal instrumentation products for advanced temperature measurement and control in these markets. Our products are designed to enable new process technologies, improve productivity, and lower the cost of ownership for our customers. We also provide repair and maintenance services for all of our products. We principally serve original equipment manufacturers ("OEM") and end customers in the semiconductor, flat panel display, high voltage, solar panel, and other industrial capital equipment markets. Our products are used in diverse markets, applications, and processes including the manufacture of capital equipment for semiconductor device manufacturing, thin film applications for thin film renewables and architectural glass, and for other thin film applications including flat panel displays, and industrial coatings. Services Our global support services group offers in-warranty and out-of-warranty repair services in the regions in which we operate, providing us with preventive maintenance opportunities. Our customers continue to pursue low cost of ownership of their capital equipment and are increasingly sensitive to the significant costs of system downtime. They expect that suppliers offer comprehensive local repair service and customer support. To meet these market requirements, we maintain a worldwide support organization comprising of both direct and indirect activities through partnership with local distributors primarily in the United States ("U.S."), the People’s Republic of China ("PRC"), Japan, South Korea, Taiwan, Germany, and United Kingdom. As part of our ongoing service business, we satisfy our service obligations under preventative maintenance contracts and extended warranties which had previously been offered on our discontinued inverter products. Any up-front fees received for extended warranties or maintenance plans are deferred. Revenue under these arrangements are recognized ratably over the underlying terms as we do not have historical information which would allow us to project the estimated service usage pattern. We have deferred revenue related to our extended warranties and service contracts totaling $36.3 million as of March 31, 2018 and $37.5 million as of December 31, 2017 . Disaggregation of Revenue The following table presents our net sales by product line: Three Months Ended March 31, 2018 2017 Semiconductor capital market $ 136,010 $ 104,648 Industrial power capital market 35,199 24,179 Global support 24,408 20,524 Total $ 195,617 $ 149,351 The following table presents our net sales by geographic region: Three Months Ended March 31, 2018 2017 Sales to external customers: United States $ 130,369 66.5 % $ 104,715 70.1 % Canada 111 0.1 % 16 0.1 % North America 130,480 66.6 % 104,731 70.2 % People's Republic of China 9,551 4.9 % 8,133 5.4 % Other Asian countries 30,307 15.5 % 21,436 14.4 % Asia 39,858 20.4 % 29,569 19.8 % Germany 19,286 9.9 % 11,854 7.9 % United Kingdom 1,948 1.0 % 3,197 2.1 % Other European countries 4,045 2.1 % — — % Europe 25,279 13.0 % 15,051 10.0 % Total $ 195,617 100.0 % $ 149,351 100.0 %

Discontinued Operations (Notes)

Discontinued Operations (Notes)	3 Months Ended
	Mar. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]	DISCONTINUED OPERATIONS In December 2015, we completed the wind down of engineering, manufacturing and sales of our solar inverter product line (the "inverter business"). Accordingly, the results of our inverter business have been reflected as "Income from discontinued operations, net of income taxes" on our Consolidated Statements of Operations for all periods presented herein. The effect of our sales of extended inverter warranties to our customers continues to be reflected in deferred revenue in our Consolidated Balance Sheets. Deferred revenue for extended inverter warranties and the associated costs of warranty service will be reflected in Sales and Cost of goods sold, respectively, from continuing operations in future periods in our Consolidated Statement of Operations, as the deferred revenue, is earned and the associated services are rendered. Extended warranties related to the inverter product line are no longer offered. The significant items included in "Income from discontinued operations, net of income taxes" are as follows: Three Months Ended March 31, 2018 2017 Sales $ — $ — Cost of sales 112 (828 ) Total operating income (including restructuring) (61 ) (1,120 ) Operating (loss) income from discontinued operations (51 ) 1,948 Other income 124 163 Income from discontinued operations before income taxes 73 2,111 (Benefit) provision for income taxes (67 ) 17 Income from discontinued operations, net of income taxes $ 140 $ 2,094 Assets and Liabilities of discontinued operations within the Condensed Consolidated Balance Sheets are comprised of the following: March 31, December 31, 2018 2017 Cash and cash equivalents $ 7,654 $ 7,754 Accounts and other receivables, net 1,379 1,363 Inventories 605 418 Current assets of discontinued operations $ 9,638 $ 9,535 Other assets $ 71 $ 72 Deferred income tax assets 11,013 11,013 Non-current assets of discontinued operations $ 11,084 $ 11,085 Accounts payable and other accrued expenses $ 517 $ 545 Accrued warranty 6,755 7,305 Current liabilities of discontinued operations $ 7,272 $ 7,850 Accrued warranty $ 14,109 $ 15,112 Other liabilities 170 165 Non-current liabilities of discontinued operations $ 14,279 $ 15,277

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES The following table sets out the tax expense and the effective tax rate for our income from continuing operations: Three Months Ended March 31, 2018 2017 Income from continuing operations, before income taxes $ 56,129 $ 40,060 Provision for income taxes 9,759 4,619 Effective tax rate 17.4 % 11.5 % On December 22, 2017, the U.S. enacted the 2017 Tax Cuts and Jobs Act (“Tax Act”), which contains several key tax provisions that affected our financial results for 2017, including a one-time mandatory transition tax on our accumulated foreign earnings and the reduction of the corporate income tax rate from 35% to 21% , effective January 1, 2018, which required a revaluation of our U.S. deferred tax assets. The Tax Act also contains several key tax provisions that will affect our financial results for 2018, including reduction of the corporate income tax rate from 35% to 21% and application of the global intangible low-taxed income of foreign subsidiaries (“GILTI tax”), among others. In December 2017, the SEC staff issued Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act (SAB 118), which allows us to record provisional amounts during a measurement period not to extend beyond one year of the enactment date. Since the Tax Act was passed late in the fourth quarter of 2017, and ongoing guidance and accounting interpretation is expected over the next 12 months, we consider the accounting for the transition tax, deferred tax re-measurements, and other items to be incomplete due to the forthcoming guidance and our ongoing analysis of final year-end data and tax positions. We expect to complete our analysis within the measurement period in accordance with SAB 118. Our effective tax rates differ from the U.S. federal statutory rate of 21% and 35% for the three months ended March 31, 2018 and 2017, respectively, primarily due to the benefit of earnings in foreign jurisdictions which are subject to lower tax rates. Our effective tax rate for the three months ended March 31, 2018 was also impacted by the effect of the recently enacted Tax Act, with the benefit from the corporate income tax rate reduction to 21% offset by additional GILTI tax, and entry into additional foreign taxable jurisdictions. Additionally, the March 2018 rate includes $1.9 million in tax expense related to our change in estimated U.S. transition tax. Our policy is to classify accrued interest and penalties related to unrecognized tax benefits in our income tax provision. The amount of interest and penalties accrued related to our unrecognized tax benefits for the three months ended March 31, 2018 and 2017 was not significant.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
EARNINGS PER SHARE	EARNINGS PER SHARE Basic earnings per share ("EPS") is computed by dividing income available to common stockholders by the weighted-average number of common shares outstanding during the period. The computation of our diluted EPS is similar to the computation of our basic EPS except that the denominator is increased to include the number of additional common shares that would have been outstanding (using the if-converted and treasury stock methods), if our outstanding stock options and restricted stock units had been converted to common shares, and if such assumed conversion is dilutive. The following is a reconciliation of the weighted-average shares outstanding used in the calculation of basic and diluted EPS for the three months ended March 31, 2018 and 2017 : Three Months Ended March 31, 2018 2017 Income from continuing operations $ 46,370 $ 35,441 Income attributable to noncontrolling interest 31 — Income from continuing operations attributable to Advanced Energy Industries, Inc. $ 46,339 $ 35,441 Basic weighted-average common shares outstanding 39,619 39,738 Assumed exercise of dilutive stock options and restricted stock units 376 441 Diluted weighted-average common shares outstanding 39,995 40,179 Continuing operations: Basic earnings per share $ 1.17 $ 0.89 Diluted earnings per share $ 1.16 $ 0.88 The following restricted stock units were excluded in the computation of diluted earnings per share because they were anti-dilutive: Three Months Ended March 31, 2018 2017 Restricted stock units 2 1 Stock Buyback In September 2015, our Board of Directors authorized a program to repurchase up to $150.0 million of our stock over a thirty-month period. In November 2017, our Board of Directors approved an extension to the share repurchase program to December 2019 from its original maturity of March 2018. As of March 31, 2018 , we had $57.3 million remaining for the authorized repurchase of shares. In March 2018, we entered into Stock Repurchase Plan and Agreement to repurchase up to $50.0 million of our common stock through December 31, 2018 subject to certain pricing conditions. In March 2018 we repurchased $12.8 million of shares of our common stock in the open market under the Stock Repurchase Plan and Agreement. A total of 180,942 shares of our common stock was repurchased at an average price of $70.47 per share. There were no shares repurchased from related parties. The $12.8 million share repurchase was recognized as a reduction to Additional paid-in capital. Repurchased shares were retired and assumed the status of authorized and unissued shares. As of March 31, 2018 , we had $37.2 million remaining for the authorized repurchase of shares under the Stock Repurchase Plan and Agreement. Subsequent to March 31, 2018 we repurchased $15.7 million of shares of our common stock in the open market under the Stock Repurchase Plan and Agreement. A total of 254,015 shares of our common stock was repurchased at an average price of $62.01 per share.

Marketable Securities

Marketable Securities	3 Months Ended
	Mar. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	MARKETABLE SECURITIES AND ASSETS MEASURED AT FAIR VALUE Our investments with original maturities of more than three months at time of purchase and that are intended to be held for no more than 12 months, are considered marketable securities available for sale. Our marketable securities consist of certificates of deposit as follows: March 31, 2018 December 31, 2017 Cost Fair Value Cost Fair Value Total marketable securities $ 3,196 $ 3,197 $ 3,103 $ 3,104 The maturities of our marketable securities available for sale as of March 31, 2018 are as follows: Earliest Latest Certificates of deposit 4/10/2018 to 3/18/2019 The value and liquidity of the marketable securities we hold are affected by market conditions, as well as the ability of the issuers of such securities to make principal and interest payments when due, and the functioning of the markets in which these securities are traded. As of March 31, 2018 , we do not believe any of the underlying issuers of our marketable securities are at risk of default. The following tables present information about our marketable securities measured at fair value, on a recurring basis, as of March 31, 2018 and December 31, 2017 . The tables indicate the fair value hierarchy of the valuation techniques utilized to determine fair value. We did not have any financial liabilities measured at fair value, on a recurring basis, as of March 31, 2018 and December 31, 2017 . March 31, 2018 Level 1 Level 2 Level 3 Total Total marketable securities $ — $ 3,197 $ — $ 3,197 December 31, 2017 Level 1 Level 2 Level 3 Total Total marketable securities $ — $ 3,104 $ — $ 3,104 There were no transfers in or out of Level 1, 2, or 3 fair value measurements during the three months ended March 31, 2018 .

Derivative Financial Instrument

Derivative Financial Instruments	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE FINANCIAL INSTRUMENTS	DERIVATIVE FINANCIAL INSTRUMENTS We are impacted by changes in foreign currency exchange rates. We manage these risks through the use of derivative financial instruments, primarily forward contracts with banks. We did not enter into any new foreign currency exchange forward contracts during the three months ended March 31, 2018 . During the three months ended March 31, 2017 , we entered into foreign currency exchange forward contracts to manage the exchange rate risk associated with intercompany debt denominated in nonfunctional currencies. These derivative instruments are not designated as hedges; however, they do offset the fluctuations of our intercompany debt due to foreign exchange rate changes. These forward contracts are typically for one month periods. We did not have any currency exchange rate contracts outstanding as of March 31, 2018 . At December 31, 2017 we had outstanding Euro and Pound Sterling forward contracts. The notional amount of foreign currency exchange contracts outstanding at December 31, 2017 was $16.3 million and the fair value of these contracts was not significant at December 31, 2017 . During the three months ended March 31, 2018 and 2017 the gains and losses recorded related to the foreign currency exchange contracts are as follows: Three Months Ended March 31, 2018 2017 Foreign currency (loss) gain from foreign currency exchange contracts $ (750 ) $ 39 These gains and losses were offset by corresponding gains and losses on the revaluation of the underlying intercompany debt and both are included as a component of Other income (expense), net , in our Unaudited Condensed Consolidated Statements of Operations. During the first quarter of 2017 we entered into a foreign currency exchange rate forward contract at a cost of $3.5 million , to mitigate the exchange rate risk associated with a planned offshore acquisition which was not consummated. This derivative instrument was designated as a hedge for accounting purposes. The hedge expired upon maturity in the first quarter of 2017. The cost of the forward contract is recorded as a component of Other income (expense), net in our Condensed Consolidated Statement of Operations.

Accounts and Other Receivables

Accounts and Other Receivables	3 Months Ended
	Mar. 31, 2018
Receivables [Abstract]
Accounts and Other Receivables	ACCOUNTS AND OTHER RECEIVABLE Accounts and other receivable are recorded at net realizable value. Components of accounts and other receivable, net of reserves, are as follows: March 31, December 31, 2018 2017 Amounts billed, net $ 107,190 $ 87,429 Unbilled receivables 9,710 — Total receivables, net $ 116,900 $ 87,429 Amounts billed, net consist of amounts that have been invoiced to our customers in accordance with our terms and conditions and are shown net of an allowance for doubtful accounts. Unbilled receivables consist of amounts where we have satisfied our contractual obligations related to inventory stocking contracts with customers. Such amounts typically become billable to the customer upon their consumption of the inventory managed under the stocking contracts. We anticipate that substantially all unbilled receivables will be invoiced and collected over the next twelve months.

Inventories

Inventories	3 Months Ended
	Mar. 31, 2018
Inventory Disclosure [Abstract]
INVENTORIES	INVENTORIES Our inventories are valued at the lower of cost or net realizable value and computed on a first-in, first-out (FIFO) basis. Components of inventories, net of reserves, are as follows: March 31, December 31, 2018 2017 Parts and raw materials $ 71,284 $ 58,567 Work in process 13,054 7,986 Finished goods 12,504 11,897 Total $ 96,842 $ 78,450

Property and Equipment

Property and Equipment	3 Months Ended
	Mar. 31, 2018
Property, Plant and Equipment [Abstract]
PROPERTY AND EQUIPMENT	PROPERTY AND EQUIPMENT Property and equipment, net is comprised of the following: March 31, December 31, 2018 2017 Buildings and land $ 1,846 $ 1,788 Machinery and equipment 37,886 36,579 Computer and communication equipment 25,391 26,819 Furniture and fixtures 1,479 1,568 Vehicles 273 341 Leasehold improvements 14,156 17,286 Construction in process 725 802 81,756 85,183 Less: Accumulated depreciation (61,050 ) (67,388 ) Property and equipment, net $ 20,706 $ 17,795 Depreciation expense recorded in continuing operations and included in selling, general and administrative expense is as follows: Three Months Ended March 31, 2018 2017 Depreciation expense $ 1,604 $ 1,025

Goodwill

Goodwill	3 Months Ended
	Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL	GOODWILL The following summarizes the changes in goodwill during the three months ended March 31, 2018 : Beginning Balance Additions Effect of Changes in Exchange Rates Ending Balance March 31, 2018 $ 53,812 $ 110 $ 984 $ 54,906

Intangible Assets

Intangible Assets	3 Months Ended
	Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
INTANGIBLE ASSETS	INTANGIBLE ASSETS Intangible assets consisted of the following as of March 31, 2018 and December 31, 2017: March 31, 2018 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Customer relationships $ 30,885 $ (11,763 ) $ 19,122 Technology 19,397 (6,192 ) 13,205 Trademarks and other 2,707 (1,589 ) 1,118 Total $ 52,989 $ (19,544 ) $ 33,445 December 31, 2017 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Customer relationships $ 30,034 $ (10,787 ) $ 19,247 Technology 18,702 (5,559 ) 13,143 Trademarks and other 2,623 (1,514 ) 1,109 Total $ 51,359 $ (17,860 ) $ 33,499 Amortization expense related to intangible assets is as follows: Three Months Ended March 31, 2018 2017 Amortization expense $ 1,257 $ 962 Estimated amortization expense related to intangibles is as follows: Year Ending December 31, 2018 (remaining) $ 3,778 2019 5,019 2020 4,313 2021 4,207 2022 3,938 Thereafter 12,190 Total $ 33,445

Warranties

Warranties	3 Months Ended
	Mar. 31, 2018
Product Warranties Disclosures [Abstract]
WARRANTIES	WARRANTIES Provisions of our sales agreements include customary product warranties, ranging from 12 months to 24 months following installation. The estimated cost of our warranty obligation is recorded when revenue is recognized and is based upon our historical experience by product, configuration and geographic region. Our estimated warranty obligation is included in Other accrued expenses in our Consolidated Balance Sheets. Changes in our product warranty obligation are as follows: Three Months Ended March 31, 2018 2017 Balances at beginning of period $ 2,312 $ 2,329 Warranty liabilities acquired 92 — Increases to accruals 178 2,181 Warranty expenditures (506 ) (389 ) Effect of changes in exchange rates 8 5 Balances at end of period $ 2,084 $ 4,126

Pension Liability (Notes)

Pension Liability (Notes)	3 Months Ended
	Mar. 31, 2018
Retirement Benefits [Abstract]
Pension Liability	PENSION LIABILITY In connection with the acquisition of HiTek Power Group, a privately-held provider of high voltage power solutions, in 2014, we acquired the HiTek Power Limited Pension Scheme (the "HiTek Plan"). The HiTek Plan has been closed to new participants since April 1, 2002 and to additional accruals since April 5, 2005. In order to measure the expense and related benefit obligation, various assumptions are made including discount rates used to value the obligation, expected return on plan assets used to fund these expenses and estimated future inflation rates. These assumptions are based on historical experience as well as facts and circumstances. An actuarial analysis is used to measure the expense and liability associated with pension benefits. We are committed to make annual fixed payments of $0.9 million into the HiTek Plan through April 30, 2024, and then $1.9 million from May 1, 2024 through November 30, 2033. The net pension liability is included in Other long-term liabilities in our balance sheet as follows: March 31, December 31, 2018 2017 Pension liability $ 20,490 $ 19,797 The following table sets forth the components of net periodic pension cost for the three months ended March 31, 2018 and 2017 : Three Months Ended March 31, 2018 2017 Interest cost $ 218 $ 264 Expected return on plan assets (161 ) (140 ) Amortization of actuarial gains and losses 136 70 Net periodic pension cost $ 193 $ 194

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
STOCK-BASED COMPENSATION	Changes in the outstanding RSU awards during the three months ended March 31, 2018 were as follows: Number of RSUs Weighted-Average Grant Date Fair Value RSUs outstanding at beginning of period 386 $ 51.06 RSUs granted 160 $ 69.32 RSUs vested (155 ) $ 52.59 RSUs forfeited (55 ) $ 47.51 RSUs outstanding at end of period 336 $ 59.64 STOCK-BASED COMPENSATION On May 4, 2017, the shareholders approved the Company's 2017 Omnibus Incentive Plan ("the 2017 Plan") and all shares that were then available for issuance under the 2008 Omnibus Incentive Plan are now available for issuance under the 2017 Plan. The 2017 Plan provides for the grant of stock options, stock appreciation rights, restricted stock, stock units (including deferred stock units), unrestricted stock, and dividend equivalent rights. Any of the awards issued under the 2017 Plan may be issued as performance-based awards to align compensation awards to the attainment of annual or long-term performance goals. As of March 31, 2018 , there were 2.7 million shares available for grant and 3.3 million shares reserved under the 2017 Plan. Restricted stock units ("RSU’s") are generally granted with a grant date fair value equal to the market price of our stock at the date of grant and with either a three or four year vesting schedule or performance-based vesting as determined at the time of grant. Stock option awards are generally granted with an exercise price equal to the market price of our stock at the date of grant and with either a three or four year vesting schedule or performance-based vesting as determined at the time of grant. Stock option awards generally have a term of 10 years. We recognize stock-based compensation expense based on the fair value of the awards issued and the functional area of the employee receiving the award. Stock-based compensation for the three months ended March 31, 2018 and 2017 was as follows: Three Months Ended March 31, 2018 2017 Stock-based compensation expense $ 4,494 $ 3,398 Changes in the outstanding RSU awards during the three months ended March 31, 2018 were as follows: Number of RSUs Weighted-Average Grant Date Fair Value RSUs outstanding at beginning of period 386 $ 51.06 RSUs granted 160 $ 69.32 RSUs vested (155 ) $ 52.59 RSUs forfeited (55 ) $ 47.51 RSUs outstanding at end of period 336 $ 59.64 Changes in the outstanding stock option awards during the three months ended March 31, 2018 were as follows: Number of Options Weighted-Average Exercise Price per Share Options outstanding at beginning of period 317 $ 18.97 Options exercised (17 ) $ 18.36 Options expired (1 ) $ 12.19 Options outstanding at end of period 299 $ 19.02

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES We have firm purchase commitments and agreements with various suppliers to ensure the availability of components. The obligation as of March 31, 2018 is approximately $177.4 million . Our policy with respect to all purchase commitments is to record losses, if any, when they are probable and reasonably estimable. We continuously monitor these commitments for exposure to potential losses and will record a provision for losses when it is deemed necessary. We are involved in disputes and legal actions arising in the normal course of our business. There have been no material developments in legal proceedings in which we are involved during the three months ended March 31, 2018 .

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2018
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED PARTY TRANSACTIONS Members of our Board of Directors hold various executive positions and serve as directors at other companies, including companies that are our customers. During the three months ended March 31, 2018 , we engaged in the following transactions with companies related to members of our Board of Directors, as described below: Three Months Ended March 31, 2018 2017 Sales to related parties $ 73 $ 577 Number of related party customers 1 1 Our accounts receivable balance from related party customers with outstanding balances as of March 31, 2018 and December 31, 2017 is as follows: March 31, December 31, 2018 2017 Accounts receivable from related parties $ 7 $ 27 Number of related party customers 1 1

Geographic and Customer Informa

Geographic and Customer Information Geographic and Customer Information (Notes)	3 Months Ended
	Mar. 31, 2018
Segment Reporting Information [Line Items]
Segment Reporting Disclosure [Text Block]	SIGNIFICANT CUSTOMER INFORMATION The following table summarizes sales, and percentages of sales, by customers that individually accounted for 10% or more of our sales for the three months ended March 31, 2018 and 2017 : Three Months Ended March 31, 2018 % of Total Sales 2017 % of Total Sales Applied Materials, Inc. $ 69,872 35.7 % $ 54,518 36.5 % LAM Research 39,726 20.3 % 32,016 21.4 % The following table summarizes the accounts receivable balances, and percentages of the total accounts receivable, for customers that individually accounted for 10% or more of accounts receivable as of March 31, 2018 and December 31, 2017 : March 31, December 31, 2018 2017 Applied Materials, Inc. $ 46,131 39.5 % $ 36,755 42.0 % LAM Research 15,957 13.7 % 5,421 6.2 % Our sales to Applied Materials, Inc. and LAM Research include precision power products used in semiconductor processing and solar and flat panel display. No other customer accounted for 10% or more of our sales or accounts receivable balances during these periods.

Credit Facility

Credit Facility	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
CREDIT FACILITY	CREDIT FACILITY The Company is party to a Loan Agreement, as amended (the "Loan Agreement") with Bank of America N.A. ("BA") which provides a revolving line of credit of up to $150.0 million subject to certain funding conditions. The Loan Agreement expires in July 28, 2022 . Interest on amounts drawn shall be paid quarterly based upon the LIBOR Daily Floating Rate then in effect, plus between one and one-quarter ( 1.25% ) and one and three-quarters ( 1.75% ) percentage points depending on the Funded Debt to EBITDA ratio. As of March 31, 2018 , the interest rate was 3.13% . The Loan Agreement also requires the Company to pay the lender on a quarterly basis an unused commitment fee based on credit availability. The obligations under the Loan Agreement are unsecured until the Funded Debt to EBITDA ratio exceeds 2.0 to 1.0, at which time the Company and certain affiliates’ tangible and intangible personal property will be subject to a first priority, perfected lien and security interest in favor of BA pursuant to a Security Agreement. As of March 31, 2018 , the Company is in compliance with all covenants required under the Loan Agreement. At March 31, 2018 our credit availability under the Loan Agreement was $150.0 million . During the three months ended March 31, 2018 , we had less than $0.1 million of expenses related to interest and unused line of credit fees.

Revenue (Policies)

Revenue (Policies)	3 Months Ended
	Mar. 31, 2018
Revenue [Abstract]
Revenue Recognition, Policy [Policy Text Block]	We recognize revenue when we have satisfied our performance obligations which typically occurs when control of the products or services have been transfered to our customers. The transaction price is based upon the standalone selling price. In most transactions, we have no obligations to our customers after the date products are shipped, other than pursuant to warranty obligations. Shipping and handling fees billed to customers, if any, are recognized as revenue. The related shipping and handling costs are recognized in cost of sales. Support services include warranty and non-warranty repair services, upgrades, and refurbishments on the products we sell. Repairs that are covered under our standard warranty do not generate revenue.

Commitments and Contingencies C

Commitments and Contingencies Commitments and Contingencies (Policies)	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Our policy with respect to all purchase commitments is to record losses, if any, when they are probable and reasonably estimable.

Basis of Presentation - (Tables

Basis of Presentation - (Tables)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]	The following table reflects the cumulative-effect of the adoption of ASC 606 and ASU 2016-16 using the modified retrospective approach for: December 31, 2017 Impact of Impact of January 1, 2018 as reported ASC 606 ASU 2016-16 as adjusted Accounts and other receivable, net $ 87,429 $ 8,251 $ — $ 95,680 Inventories 78,450 (3,561 ) — 74,889 Total current assets 595,225 4,690 — 599,915 Deferred income tax assets 18,841 — 17,080 35,921 Total assets 733,308 4,690 17,080 755,078 Income taxes payable 5,365 — 921 6,286 Deferred income tax liabilities 4,556 1,143 — 5,699 Total liabilities 212,667 1,143 921 214,731 Retained earnings 333,225 3,547 16,159 352,931 Total stockholders’ equity 520,641 3,547 16,159 540,347 Total liabilities and stockholders' equity 733,308 4,690 17,080 755,078 March 31, 2018 Balances without adoption of As Reported Adjustments ASC 606 Accounts and other receivable, net $ 116,900 $ (9,710 ) $ 107,190 Inventories 96,842 4,086 100,928 Total current assets 650,572 (5,624 ) 644,948 TOTAL ASSETS 813,661 (5,624 ) 808,037 Income taxes payable 13,011 (230 ) 12,781 Total current liabilities 126,634 (230 ) 126,404 Deferred income tax liabilities 6,592 (1,143 ) 5,449 Total liabilities 236,452 (1,373 ) 235,079 Retained earnings 399,410 (4,251 ) 395,159 Advanced Energy stockholders’ equity 576,747 (4,251 ) 572,496 Total stockholders’ equity 577,209 (4,251 ) 572,958 TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY $ 813,661 $ (5,624 ) $ 808,037 Three Months Ended March 31, 2018 Balances without adoption of As Reported Adjustments ASC 606 Product sales $ 171,209 $ (1,460 ) $ 169,749 Total sales 195,617 (1,460 ) 194,157 Product cost of sales 79,806 (526 ) 79,280 Total cost of sales 91,972 (526 ) 91,446 Gross profit 103,645 (934 ) 102,711 Operating income 56,103 (934 ) 55,169 Income from continuing operations, before income taxes 56,129 (934 ) 55,195 Provision for income taxes 9,759 (230 ) 9,529 Income from continuing operations 46,370 (704 ) 45,666 Net income 46,510 (704 ) 45,806 Net income attributable to Advanced Energy Industries, Inc. $ 46,479 $ (704 ) $ 45,775 Three Months Ended March 31, 2018 Balances without adoption of As Reported Adjustments ASC 606 Net income $ 46,510 $ (704 ) $ 45,806 Changes in operating assets and liabilities, net of assets acquired: Accounts and other receivable, net (17,457 ) 1,460 (15,997 ) Inventories (17,113 ) (526 ) (17,639 ) Income taxes 5,642 (230 ) 5,412 Net cash provided by operating activities from continuing operations $ 34,885 $ — $ 34,885

Business Acquisition (Tables)

Business Acquisition (Tables)	3 Months Ended
	Mar. 31, 2018
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition	The components of the fair value of the total consideration transferred for the Trek acquisition are as follows: Cash paid to owners $ 11,723 Cash acquired (5,651 ) Total fair value of consideration transferred $ 6,072
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The following table summarizes estimated fair values of the assets acquired and liabilities assumed as of February 1, 2018: Accounts and other receivable, net $ 2,818 Inventories 4,037 Other current assets 275 Property and equipment 594 Other non-current assets 579 Deferred income tax assets 702 Accounts payable (747 ) Other accrued expenses (2,696 ) 5,562 Amortizable intangible assets: Technology 200 Customer relationships 200 Total amortizable intangible assets 400 Total identifiable net assets 5,962 Goodwill 110 Total fair value of consideration received $ 6,072
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination	A summary of the intangible assets acquired, amortization method and estimated useful lives as of February 1, 2018 follows: Amount Amortization Method Useful Life Technology $ 200 Straight-line 10 Customer relationships 200 Straight-line 10 Total $ 400

Revenue Revenue by Product Line

Revenue Revenue by Product Line (Tables)	3 Months Ended
	Mar. 31, 2018
Revenue [Abstract]
Disaggregation of Revenue [Table Text Block]	The following table presents our net sales by extended warranty and service contracts recognized over time and our product and service revenue recognized at a point in time: Three Months Ended March 31, 2018 2017 Product and service revenue recognized at point in time $ 194,683 $ 148,530 Extended warranty and service contracts recognized over time 934 821 Total $ 195,617 $ 149,351 The following table presents our net sales by product line: Three Months Ended March 31, 2018 2017 Semiconductor capital market $ 136,010 $ 104,648 Industrial power capital market 35,199 24,179 Global support 24,408 20,524 Total $ 195,617 $ 149,351 The following table presents our net sales by geographic region: Three Months Ended March 31, 2018 2017 Sales to external customers: United States $ 130,369 66.5 % $ 104,715 70.1 % Canada 111 0.1 % 16 0.1 % North America 130,480 66.6 % 104,731 70.2 % People's Republic of China 9,551 4.9 % 8,133 5.4 % Other Asian countries 30,307 15.5 % 21,436 14.4 % Asia 39,858 20.4 % 29,569 19.8 % Germany 19,286 9.9 % 11,854 7.9 % United Kingdom 1,948 1.0 % 3,197 2.1 % Other European countries 4,045 2.1 % — — % Europe 25,279 13.0 % 15,051 10.0 % Total $ 195,617 100.0 % $ 149,351 100.0 % The following table presents our net sales by extended warranty and service contracts recognized over time and our product and service revenue recognized at a point in time: Three Months Ended March 31, 2018 2017 Product and service revenue recognized at point in time $ 194,683 $ 148,530 Extended warranty and service contracts recognized over time 934 821 Total $ 195,617 $ 149,351

Revenue Revenue by Geographical

Revenue Revenue by Geographical Location (Tables)	3 Months Ended
	Mar. 31, 2018
Revenue [Abstract]
Disaggregation of Revenue [Table Text Block]	The following table presents our net sales by extended warranty and service contracts recognized over time and our product and service revenue recognized at a point in time: Three Months Ended March 31, 2018 2017 Product and service revenue recognized at point in time $ 194,683 $ 148,530 Extended warranty and service contracts recognized over time 934 821 Total $ 195,617 $ 149,351 The following table presents our net sales by product line: Three Months Ended March 31, 2018 2017 Semiconductor capital market $ 136,010 $ 104,648 Industrial power capital market 35,199 24,179 Global support 24,408 20,524 Total $ 195,617 $ 149,351 The following table presents our net sales by geographic region: Three Months Ended March 31, 2018 2017 Sales to external customers: United States $ 130,369 66.5 % $ 104,715 70.1 % Canada 111 0.1 % 16 0.1 % North America 130,480 66.6 % 104,731 70.2 % People's Republic of China 9,551 4.9 % 8,133 5.4 % Other Asian countries 30,307 15.5 % 21,436 14.4 % Asia 39,858 20.4 % 29,569 19.8 % Germany 19,286 9.9 % 11,854 7.9 % United Kingdom 1,948 1.0 % 3,197 2.1 % Other European countries 4,045 2.1 % — — % Europe 25,279 13.0 % 15,051 10.0 % Total $ 195,617 100.0 % $ 149,351 100.0 % The following table presents our net sales by extended warranty and service contracts recognized over time and our product and service revenue recognized at a point in time: Three Months Ended March 31, 2018 2017 Product and service revenue recognized at point in time $ 194,683 $ 148,530 Extended warranty and service contracts recognized over time 934 821 Total $ 195,617 $ 149,351

Revenue 606 Financial Statement

Revenue 606 Financial Statement Impacts (Tables)	3 Months Ended
	Mar. 31, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]	The following table reflects the cumulative-effect of the adoption of ASC 606 and ASU 2016-16 using the modified retrospective approach for: December 31, 2017 Impact of Impact of January 1, 2018 as reported ASC 606 ASU 2016-16 as adjusted Accounts and other receivable, net $ 87,429 $ 8,251 $ — $ 95,680 Inventories 78,450 (3,561 ) — 74,889 Total current assets 595,225 4,690 — 599,915 Deferred income tax assets 18,841 — 17,080 35,921 Total assets 733,308 4,690 17,080 755,078 Income taxes payable 5,365 — 921 6,286 Deferred income tax liabilities 4,556 1,143 — 5,699 Total liabilities 212,667 1,143 921 214,731 Retained earnings 333,225 3,547 16,159 352,931 Total stockholders’ equity 520,641 3,547 16,159 540,347 Total liabilities and stockholders' equity 733,308 4,690 17,080 755,078 March 31, 2018 Balances without adoption of As Reported Adjustments ASC 606 Accounts and other receivable, net $ 116,900 $ (9,710 ) $ 107,190 Inventories 96,842 4,086 100,928 Total current assets 650,572 (5,624 ) 644,948 TOTAL ASSETS 813,661 (5,624 ) 808,037 Income taxes payable 13,011 (230 ) 12,781 Total current liabilities 126,634 (230 ) 126,404 Deferred income tax liabilities 6,592 (1,143 ) 5,449 Total liabilities 236,452 (1,373 ) 235,079 Retained earnings 399,410 (4,251 ) 395,159 Advanced Energy stockholders’ equity 576,747 (4,251 ) 572,496 Total stockholders’ equity 577,209 (4,251 ) 572,958 TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY $ 813,661 $ (5,624 ) $ 808,037 Three Months Ended March 31, 2018 Balances without adoption of As Reported Adjustments ASC 606 Product sales $ 171,209 $ (1,460 ) $ 169,749 Total sales 195,617 (1,460 ) 194,157 Product cost of sales 79,806 (526 ) 79,280 Total cost of sales 91,972 (526 ) 91,446 Gross profit 103,645 (934 ) 102,711 Operating income 56,103 (934 ) 55,169 Income from continuing operations, before income taxes 56,129 (934 ) 55,195 Provision for income taxes 9,759 (230 ) 9,529 Income from continuing operations 46,370 (704 ) 45,666 Net income 46,510 (704 ) 45,806 Net income attributable to Advanced Energy Industries, Inc. $ 46,479 $ (704 ) $ 45,775 Three Months Ended March 31, 2018 Balances without adoption of As Reported Adjustments ASC 606 Net income $ 46,510 $ (704 ) $ 45,806 Changes in operating assets and liabilities, net of assets acquired: Accounts and other receivable, net (17,457 ) 1,460 (15,997 ) Inventories (17,113 ) (526 ) (17,639 ) Income taxes 5,642 (230 ) 5,412 Net cash provided by operating activities from continuing operations $ 34,885 $ — $ 34,885

Discontinued Operations (Tables

Discontinued Operations (Tables)	3 Months Ended
	Mar. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Groups, Including Discontinued Operations [Table Text Block]	Three Months Ended March 31, 2018 2017 Sales $ — $ — Cost of sales 112 (828 ) Total operating income (including restructuring) (61 ) (1,120 ) Operating (loss) income from discontinued operations (51 ) 1,948 Other income 124 163 Income from discontinued operations before income taxes 73 2,111 (Benefit) provision for income taxes (67 ) 17 Income from discontinued operations, net of income taxes $ 140 $ 2,094 Assets and Liabilities of discontinued operations within the Condensed Consolidated Balance Sheets are comprised of the following: March 31, December 31, 2018 2017 Cash and cash equivalents $ 7,654 $ 7,754 Accounts and other receivables, net 1,379 1,363 Inventories 605 418 Current assets of discontinued operations $ 9,638 $ 9,535 Other assets $ 71 $ 72 Deferred income tax assets 11,013 11,013 Non-current assets of discontinued operations $ 11,084 $ 11,085 Accounts payable and other accrued expenses $ 517 $ 545 Accrued warranty 6,755 7,305 Current liabilities of discontinued operations $ 7,272 $ 7,850 Accrued warranty $ 14,109 $ 15,112 Other liabilities 170 165 Non-current liabilities of discontinued operations $ 14,279 $ 15,277

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Schedule of tax expense and the effective tax rate for our income from continuing operations	The following table sets out the tax expense and the effective tax rate for our income from continuing operations: Three Months Ended March 31, 2018 2017 Income from continuing operations, before income taxes $ 56,129 $ 40,060 Provision for income taxes 9,759 4,619 Effective tax rate 17.4 % 11.5 %

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Reconciliation of the weighted-average shares outstanding used in the calculation of basic and diluted EPS	The following is a reconciliation of the weighted-average shares outstanding used in the calculation of basic and diluted EPS for the three months ended March 31, 2018 and 2017 : Three Months Ended March 31, 2018 2017 Income from continuing operations $ 46,370 $ 35,441 Income attributable to noncontrolling interest 31 — Income from continuing operations attributable to Advanced Energy Industries, Inc. $ 46,339 $ 35,441 Basic weighted-average common shares outstanding 39,619 39,738 Assumed exercise of dilutive stock options and restricted stock units 376 441 Diluted weighted-average common shares outstanding 39,995 40,179 Continuing operations: Basic earnings per share $ 1.17 $ 0.89 Diluted earnings per share $ 1.16 $ 0.88
Schedule of stock options and restricted units were excluded in the computation of diluted earnings per share because they were anti-dilutive	The following restricted stock units were excluded in the computation of diluted earnings per share because they were anti-dilutive: Three Months Ended March 31, 2018 2017 Restricted stock units 2 1

Marketable Securities (Tables)

Marketable Securities (Tables)	3 Months Ended
	Mar. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Fair Value, Assets Measured on Recurring Basis [Table Text Block]	March 31, 2018 and December 31, 2017 . The tables indicate the fair value hierarchy of the valuation techniques utilized to determine fair value. We did not have any financial liabilities measured at fair value, on a recurring basis, as of March 31, 2018 and December 31, 2017 . March 31, 2018 Level 1 Level 2 Level 3 Total Total marketable securities $ — $ 3,197 $ — $ 3,197 December 31, 2017 Level 1 Level 2 Level 3 Total Total marketable securities $ — $ 3,104 $ — $ 3,104
The composition of our marketable securities	Our marketable securities consist of certificates of deposit as follows: March 31, 2018 December 31, 2017 Cost Fair Value Cost Fair Value Total marketable securities $ 3,196 $ 3,197 $ 3,103 $ 3,104
The maturities of our marketable securities available for sale	The maturities of our marketable securities available for sale as of March 31, 2018 are as follows: Earliest Latest Certificates of deposit 4/10/2018 to 3/18/2019

Derivative Financial Instrume38

Derivative Financial Instruments Gains and Losses related to Foreign Currency Contracts (Tables)	3 Months Ended
	Mar. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) [Table Text Block]	During the three months ended March 31, 2018 and 2017 the gains and losses recorded related to the foreign currency exchange contracts are as follows: Three Months Ended March 31, 2018 2017 Foreign currency (loss) gain from foreign currency exchange contracts $ (750 ) $ 39

Accounts and Other Receivables

Accounts and Other Receivables (Tables)	3 Months Ended
	Mar. 31, 2017
Receivables [Abstract]
Schedule of Accounts, Notes, Loans and Financing Receivable	Components of accounts and other receivable, net of reserves, are as follows: March 31, December 31, 2018 2017 Amounts billed, net $ 107,190 $ 87,429 Unbilled receivables 9,710 — Total receivables, net $ 116,900 $ 87,429

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Mar. 31, 2018
Inventory Disclosure [Abstract]
Components of inventories	Our inventories are valued at the lower of cost or net realizable value and computed on a first-in, first-out (FIFO) basis. Components of inventories, net of reserves, are as follows: March 31, December 31, 2018 2017 Parts and raw materials $ 71,284 $ 58,567 Work in process 13,054 7,986 Finished goods 12,504 11,897 Total $ 96,842 $ 78,450

Property and Equipment (Tables)

Property and Equipment (Tables)	3 Months Ended
	Mar. 31, 2018
Property, Plant and Equipment [Abstract]
Details of property and equipment	Property and equipment, net is comprised of the following: March 31, December 31, 2018 2017 Buildings and land $ 1,846 $ 1,788 Machinery and equipment 37,886 36,579 Computer and communication equipment 25,391 26,819 Furniture and fixtures 1,479 1,568 Vehicles 273 341 Leasehold improvements 14,156 17,286 Construction in process 725 802 81,756 85,183 Less: Accumulated depreciation (61,050 ) (67,388 ) Property and equipment, net $ 20,706 $ 17,795
Depreciation expense recorded in continuing operations	Three Months Ended March 31, 2018 2017 Depreciation expense $ 1,604 $ 1,025

Goodwill (Tables)

Goodwill (Tables)	3 Months Ended
	Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of the changes in goodwill	The following summarizes the changes in goodwill during the three months ended March 31, 2018 : Beginning Balance Additions Effect of Changes in Exchange Rates Ending Balance March 31, 2018 $ 53,812 $ 110 $ 984 $ 54,906

Intangible Assets (Tables)

Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of other intangible assets	ntangible assets consisted of the following as of March 31, 2018 and December 31, 2017: March 31, 2018 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Customer relationships $ 30,885 $ (11,763 ) $ 19,122 Technology 19,397 (6,192 ) 13,205 Trademarks and other 2,707 (1,589 ) 1,118 Total $ 52,989 $ (19,544 ) $ 33,445 December 31, 2017 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Customer relationships $ 30,034 $ (10,787 ) $ 19,247 Technology 18,702 (5,559 ) 13,143 Trademarks and other 2,623 (1,514 ) 1,109 Total $ 51,359 $ (17,860 ) $ 33,499
Schedule of amortization expense relating to other intangible assets	Three Months Ended March 31, 2018 2017 Amortization expense $ 1,257 $ 962
Schedule of expected future amortization expense	Year Ending December 31, 2018 (remaining) $ 3,778 2019 5,019 2020 4,313 2021 4,207 2022 3,938 Thereafter 12,190 Total $ 33,445

Warranties (Tables)

Warranties (Tables)	3 Months Ended
	Mar. 31, 2018
Product Warranties Disclosures [Abstract]
Changes in accrued product warranties	Three Months Ended March 31, 2018 2017 Balances at beginning of period $ 2,312 $ 2,329 Warranty liabilities acquired 92 — Increases to accruals 178 2,181 Warranty expenditures (506 ) (389 ) Effect of changes in exchange rates 8 5 Balances at end of period $ 2,084 $ 4,126

Pension Liability (Tables)

Pension Liability (Tables)	3 Months Ended
	Mar. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Schedule of Net Funded Status [Table Text Block]	The net pension liability is included in Other long-term liabilities in our balance sheet as follows: March 31, December 31, 2018 2017 Pension liability $ 20,490 $ 19,797
Schedule of Net Benefit Costs [Table Text Block]	the three months ended March 31, 2018 and 2017 : Three Months Ended March 31, 2018 2017 Interest cost $ 218 $ 264 Expected return on plan assets (161 ) (140 ) Amortization of actuarial gains and losses 136 70 Net periodic pension cost $ 193 $ 194

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of stock-based compensation	Stock-based compensation for the three months ended March 31, 2018 and 2017 was as follows: Three Months Ended March 31, 2018 2017 Stock-based compensation expense $ 4,494 $ 3,398
Summary of stock option activity	Number of RSUs Weighted-Average Grant Date Fair Value RSUs outstanding at beginning of period 386 $ 51.06 RSUs granted 160 $ 69.32 RSUs vested (155 ) $ 52.59 RSUs forfeited (55 ) $ 47.51 RSUs outstanding at end of period 336 $ 59.64 Changes in the outstanding stock option awards during the three months ended March 31, 2018 were as follows: Number of Options Weighted-Average Exercise Price per Share Options outstanding at beginning of period 317 $ 18.97 Options exercised (17 ) $ 18.36 Options expired (1 ) $ 12.19 Options outstanding at end of period 299 $ 19.02

Related Party Transactions (Tab

Related Party Transactions (Tables)	3 Months Ended
	Mar. 31, 2018
Related Party Transaction [Line Items]
Schedule of related party transactions	Members of our Board of Directors hold various executive positions and serve as directors at other companies, including companies that are our customers. During the three months ended March 31, 2018 , we engaged in the following transactions with companies related to members of our Board of Directors, as described below: Three Months Ended March 31, 2018 2017 Sales to related parties $ 73 $ 577 Number of related party customers 1 1 Our accounts receivable balance from related party customers with outstanding balances as of March 31, 2018 and December 31, 2017 is as follows: March 31, December 31, 2018 2017 Accounts receivable from related parties $ 7 $ 27 Number of related party customers 1 1

Geographic and Customer Infor48

Geographic and Customer Information (Tables)	3 Months Ended
	Mar. 31, 2018
Significant Customer Information [Abstract]
Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]	The following table summarizes sales, and percentages of sales, by customers that individually accounted for 10% or more of our sales for the three months ended March 31, 2018 and 2017 : Three Months Ended March 31, 2018 % of Total Sales 2017 % of Total Sales Applied Materials, Inc. $ 69,872 35.7 % $ 54,518 36.5 % LAM Research 39,726 20.3 % 32,016 21.4 % The following table summarizes the accounts receivable balances, and percentages of the total accounts receivable, for customers that individually accounted for 10% or more of accounts receivable as of March 31, 2018 and December 31, 2017 : March 31, December 31, 2018 2017 Applied Materials, Inc. $ 46,131 39.5 % $ 36,755 42.0 % LAM Research 15,957 13.7 % 5,421 6.2 %

Revenue by timing of Transfer (

Revenue by timing of Transfer (Tables)	3 Months Ended
	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Disaggregation of Revenue [Table Text Block]	The following table presents our net sales by extended warranty and service contracts recognized over time and our product and service revenue recognized at a point in time: Three Months Ended March 31, 2018 2017 Product and service revenue recognized at point in time $ 194,683 $ 148,530 Extended warranty and service contracts recognized over time 934 821 Total $ 195,617 $ 149,351 The following table presents our net sales by product line: Three Months Ended March 31, 2018 2017 Semiconductor capital market $ 136,010 $ 104,648 Industrial power capital market 35,199 24,179 Global support 24,408 20,524 Total $ 195,617 $ 149,351 The following table presents our net sales by geographic region: Three Months Ended March 31, 2018 2017 Sales to external customers: United States $ 130,369 66.5 % $ 104,715 70.1 % Canada 111 0.1 % 16 0.1 % North America 130,480 66.6 % 104,731 70.2 % People's Republic of China 9,551 4.9 % 8,133 5.4 % Other Asian countries 30,307 15.5 % 21,436 14.4 % Asia 39,858 20.4 % 29,569 19.8 % Germany 19,286 9.9 % 11,854 7.9 % United Kingdom 1,948 1.0 % 3,197 2.1 % Other European countries 4,045 2.1 % — — % Europe 25,279 13.0 % 15,051 10.0 % Total $ 195,617 100.0 % $ 149,351 100.0 % The following table presents our net sales by extended warranty and service contracts recognized over time and our product and service revenue recognized at a point in time: Three Months Ended March 31, 2018 2017 Product and service revenue recognized at point in time $ 194,683 $ 148,530 Extended warranty and service contracts recognized over time 934 821 Total $ 195,617 $ 149,351

Basis of Presentation - Cumulat

Basis of Presentation - Cumulative Effect of Recently Adopted Accounting Pronouncements (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Stockholders' Equity Attributable to Parent	$ 576,747		$ 520,641
Accounts and Other Receivables, Net, Current	116,900	$ 95,680	87,429
Inventories	96,842	74,889	78,450
Assets, Current	650,572	599,915	595,225
Deferred income tax assets	38,741	35,921	18,841
Assets	813,661	755,078	733,308
Accrued Income Taxes, Current	13,011	6,286	5,365
Deferred Tax Liabilities, Net, Noncurrent	6,592	5,699	4,556
Liabilities	236,452	214,731	212,667
Retained Earnings (Accumulated Deficit)	399,410	352,931	333,225
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	577,209	540,347	520,641
Liabilities and Equity	813,661	755,078	$ 733,308
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Stockholders' Equity Attributable to Parent	572,496
Accounts and Other Receivables, Net, Current	107,190
Inventories	100,928
Assets, Current	644,948
Assets	808,037
Accrued Income Taxes, Current	12,781
Deferred Tax Liabilities, Net, Noncurrent	5,449
Liabilities	235,079
Retained Earnings (Accumulated Deficit)	395,159
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	572,958
Liabilities and Equity	808,037
Accounting Standards Update 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Stockholders' Equity Attributable to Parent	(4,251)
Accounts and Other Receivables, Net, Current	(9,710)	8,251
Inventories	4,086	(3,561)
Assets, Current	(5,624)	4,690
Deferred income tax assets		0
Assets	(5,624)	4,690
Accrued Income Taxes, Current	(230)	0
Deferred Tax Liabilities, Net, Noncurrent	(1,143)	1,143
Liabilities	(1,373)	1,143
Retained Earnings (Accumulated Deficit)	(4,251)	3,547
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(4,251)	3,547
Liabilities and Equity	$ (5,624)	4,690
Accounting Standards Update 2016-16 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts and Other Receivables, Net, Current		0
Inventories		0
Assets, Current		0
Deferred income tax assets		17,080
Assets		17,080
Accrued Income Taxes, Current		921
Deferred Tax Liabilities, Net, Noncurrent		0
Liabilities		921
Retained Earnings (Accumulated Deficit)		16,159
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		16,159
Liabilities and Equity		$ 17,080

Business Acquisition - (Details

Business Acquisition - (Details)	Feb. 01, 2018
Trek Holding Co., LTD [Member] | Trek Holding Co., LTD [Member]
Business Acquisition [Line Items]
Ownership percentage	95.00%

Business Acquisition Considerat

Business Acquisition Consideration Transferred (Details) - Excelsys Acquisition [Member] $ in Thousands	Feb. 01, 2018USD ($)
Business Acquisition [Line Items]
Cash paid to owners	$ 11,723
Cash acquired	(5,651)
Total fair value of consideration transferred	$ 6,072

Business Acquisition Assets Acq

Business Acquisition Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Feb. 01, 2018	Mar. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill		$ 54,906	$ 53,812
Excelsys Acquisition [Member]
Business Acquisition [Line Items]
Accounts receivable, net	$ 2,818
Inventories	4,037
Other current assets	275
Property and equipment	594
Other non-current assets	579
Deferred income tax assets	702
Accounts payable	(747)
Other accrued expenses	(2,696)
Net tangible assets acquired (liabilities) assumed	5,562
Amortizable intangible assets:	400
Total identifiable net assets	5,962
Goodwill	110
Total fair value of consideration received	6,072
Customer Relationships [Member] | Excelsys Acquisition [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:	200
Technology Equipment [Member] | Excelsys Acquisition [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:	$ 200

Business Acquisition Intangible

Business Acquisition Intangible Assets Acquired (Details) - Excelsys Acquisition [Member] $ in Thousands	Feb. 01, 2018USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets:	$ 400
Tradename [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets:	$ 200
Useful Life	10 years
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets:	$ 200
Technology Equipment [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Useful Life	10 years

Revenue - Extended Warranty Rev

Revenue - Extended Warranty Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue, Net	$ 195,617	$ 149,351
Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	934	821
Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	$ 194,683	$ 148,530

Revenue Revenue by product li56

Revenue Revenue by product line (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Product	$ 171,209	$ 128,827
Services	24,408	20,524
Revenue, Net	195,617	149,351
CANADA
Disaggregation of Revenue [Line Items]
Revenue, Net	111	16
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenue, Net	130,369	104,715
North America [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	130,480	104,731
CHINA
Disaggregation of Revenue [Line Items]
Revenue, Net	9,551	8,133
Other Asian Countries [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	30,307	21,436
Asia [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	39,858	29,569
GERMANY
Disaggregation of Revenue [Line Items]
Revenue, Net	19,286	11,854
UNITED KINGDOM
Disaggregation of Revenue [Line Items]
Revenue, Net	1,948	3,197
Other European Countries [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	4,045	0
Europe [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	25,279	15,051
Semiconductor Capital Marker [Member]
Disaggregation of Revenue [Line Items]
Product	136,010	104,648
Industrial Power Capital Market [Member]
Disaggregation of Revenue [Line Items]
Product	$ 35,199	$ 24,179
Geographic Concentration Risk [Member] | Sales Revenue, Net [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	100.00%	100.00%
Geographic Concentration Risk [Member] | Sales Revenue, Net [Member] | CANADA
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	0.10%	0.10%
Geographic Concentration Risk [Member] | Sales Revenue, Net [Member] | UNITED STATES
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	66.50%	70.10%
Geographic Concentration Risk [Member] | Sales Revenue, Net [Member] | North America [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	66.60%	70.20%
Geographic Concentration Risk [Member] | Sales Revenue, Net [Member] | CHINA
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	4.90%	5.40%
Geographic Concentration Risk [Member] | Sales Revenue, Net [Member] | Other Asian Countries [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	15.50%	14.40%
Geographic Concentration Risk [Member] | Sales Revenue, Net [Member] | Asia [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	20.40%	19.80%
Geographic Concentration Risk [Member] | Sales Revenue, Net [Member] | GERMANY
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	9.90%	7.90%
Geographic Concentration Risk [Member] | Sales Revenue, Net [Member] | UNITED KINGDOM
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	1.00%	2.10%
Geographic Concentration Risk [Member] | Sales Revenue, Net [Member] | Other European Countries [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	2.10%	0.00%
Geographic Concentration Risk [Member] | Sales Revenue, Net [Member] | Europe [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	13.00%	10.00%

Revenue ASC 606 Financial State

Revenue ASC 606 Financial Statement Impact (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Jan. 01, 2018	Dec. 31, 2017
Balance Sheet Related Disclosures [Abstract]
Accounts and Other Receivables, Net, Current	$ 116,900		$ 95,680	$ 87,429
Inventories	96,842		74,889	78,450
Assets, Current	650,572		599,915	595,225
Assets	813,661		755,078	733,308
Accrued Income Taxes, Current	13,011		6,286	5,365
Liabilities, Current	126,634			106,119
Deferred Tax Liabilities, Net, Noncurrent	6,592		5,699	4,556
Liabilities	236,452		214,731	212,667
Retained Earnings (Accumulated Deficit)	399,410		352,931	333,225
Stockholders' Equity Attributable to Parent	576,747			520,641
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	577,209		540,347	520,641
Liabilities and Equity	813,661		755,078	$ 733,308
Income Statement [Abstract]
Product	171,209	$ 128,827
Revenue, Net	195,617	149,351
Product	79,806	60,117
Cost of Goods and Services Sold	91,972	70,520
Gross Profit	103,645	78,831
Operating Income (Loss)	56,103	43,268
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	56,129	40,060
Provision for income taxes	9,759	4,619
Income from continuing operations attributable to Advanced Energy Industries, Inc.	46,370	35,441
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	46,510	37,535
Net Income (Loss) Attributable to Parent	46,479	37,535
Statement of Cash Flows [Abstract]
Increase (Decrease) in Accounts Receivable	17,457	431
Increase (Decrease) in Inventories	17,113	8,047
Increase (Decrease) in Income Taxes	5,642	3,286
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	34,885	$ 42,659
Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Income Statement [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(704)
Statement of Cash Flows [Abstract]
Increase (Decrease) in Accounts Receivable	1,460
Increase (Decrease) in Inventories	(526)
Increase (Decrease) in Income Taxes	(230)
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	0
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Balance Sheet Related Disclosures [Abstract]
Accounts and Other Receivables, Net, Current	107,190
Inventories	100,928
Assets, Current	644,948
Assets	808,037
Accrued Income Taxes, Current	12,781
Liabilities, Current	126,404
Deferred Tax Liabilities, Net, Noncurrent	5,449
Liabilities	235,079
Retained Earnings (Accumulated Deficit)	395,159
Stockholders' Equity Attributable to Parent	572,496
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	572,958
Liabilities and Equity	808,037
Income Statement [Abstract]
Product	169,749
Revenue, Net	194,157
Product	79,280
Cost of Goods and Services Sold	91,446
Gross Profit	102,711
Operating Income (Loss)	55,169
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	55,195
Provision for income taxes	9,529
Income from continuing operations attributable to Advanced Energy Industries, Inc.	45,666
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	45,806
Net Income (Loss) Attributable to Parent	45,775
Statement of Cash Flows [Abstract]
Increase (Decrease) in Accounts Receivable	15,997
Increase (Decrease) in Inventories	17,639
Increase (Decrease) in Income Taxes	5,412
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	34,885
Accounting Standards Update 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Balance Sheet Related Disclosures [Abstract]
Accounts and Other Receivables, Net, Current	(9,710)		8,251
Inventories	4,086		(3,561)
Assets, Current	(5,624)		4,690
Assets	(5,624)		4,690
Accrued Income Taxes, Current	(230)		0
Liabilities, Current	(230)
Deferred Tax Liabilities, Net, Noncurrent	(1,143)		1,143
Liabilities	(1,373)		1,143
Retained Earnings (Accumulated Deficit)	(4,251)		3,547
Stockholders' Equity Attributable to Parent	(4,251)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(4,251)		3,547
Liabilities and Equity	(5,624)		$ 4,690
Income Statement [Abstract]
Product	(1,460)
Revenue, Net	(1,460)
Product	(526)
Cost of Goods and Services Sold	(526)
Gross Profit	(934)
Operating Income (Loss)	(934)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	(934)
Provision for income taxes	(230)
Income from continuing operations attributable to Advanced Energy Industries, Inc.	(704)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(704)
Net Income (Loss) Attributable to Parent	$ (704)

Revenue Narrative (Details)

Revenue Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Revenue [Abstract]
Deferred Service Revenue	$ 36.3	$ 37.5

Discontinued Operations Stateme

Discontinued Operations Statement of Operations for Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales	$ 0	$ 0
Cost of sales	112	(828)
Total operating income (including restructuring)	(61)	(1,120)
Operating (loss) income from discontinued operations	(51)	1,948
Other income	124	163
(Benefit) provision for income taxes	73	2,111
(Benefit) provision for income taxes	(67)	17
Income from discontinued operations, net of income taxes	$ 140	$ 2,094

Discontinued Operations Assets

Discontinued Operations Assets and Liabilities of Discontinued Operations (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash and cash equivalents	$ 7,654	$ 7,754	$ 6,339
Accounts and other receivables, net	1,379	1,363
Inventories	605	418
Current assets of discontinued operations	9,638	9,535
Other assets	71	72
Deferred income tax assets	11,013	11,013
Non-current assets of discontinued operations	11,084	11,085
Accounts payable and other accrued expenses	517	545
Accrued warranty	6,755	7,305
Current liabilities of discontinued operations	7,272	7,850
Accrued warranty	14,109	15,112
Other liabilities	170	165
Non-current liabilities of discontinued operations	$ 14,279	$ 15,277

Income Taxes Schedule of tax ex

Income Taxes Schedule of tax expense and the effective tax rate for our income from continuing operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Federal statutory income tax rate	21.00%	35.00%
Income from continuing operations, before income taxes	$ 56,129	$ 40,060
Provision for income taxes	$ 9,759	$ 4,619
Effective tax rate	17.40%	11.50%

Income Taxes Narrative (Details

Income Taxes Narrative (Details)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Tax Contingency [Line Items]
Federal statutory income tax rate	21.00%	35.00%

Earnings Per Share Reconciliati

Earnings Per Share Reconciliation of the weighted-average shares outstanding used in the calculation of basic and diluted EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Earnings Per Share [Abstract]
Income from continuing operations attributable to Advanced Energy Industries, Inc.	$ 46,370	$ 35,441
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	31	0
Income from continuing operations attributable to noncontrolling interest	31	0
Income from continuing operations, net of income taxes	46,339	35,441
Net Income (Loss) Attributable to Parent	$ 46,479	$ 37,535
Basic weighted-average common shares outstanding	39,619	39,738
Assumed exercise of dilutive stock options and restricted stock units	376	441
Diluted weighted-average common shares outstanding	39,995	40,179
Income from Continuing Operations:
Income (Loss) from Continuing Operations, Per Basic Share	$ 1.17	$ 0.89
Income (Loss) from Continuing Operations, Per Diluted Share	$ 1.16	$ 0.88

Earnings Per Share Schedule of

Earnings Per Share Schedule of stock options and restricted units were excluded in the computation of diluted earnings per share because they were anti-dilutive (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock options and restricted units excluded from the computation of diluted earnings per share because they were anti-dilutive	2	1

Earnings Per Share Stock Buybac

Earnings Per Share Stock Buyback (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended
	Apr. 30, 2018	Aug. 31, 2017	Mar. 31, 2018	Sep. 16, 2015
Equity, Class of Treasury Stock [Line Items]
Authorized amount			$ 50	$ 150
Treasury stock, common, value			12.8
Treasury stock, shares, acquired (in shares)		180,942
Treasury stock acquired, average cost per share (in dollars per share)		$ 70.47
Remaining authorized repurchase amount			57.3
Stock Repurchase Plan and Agreement [Member]
Equity, Class of Treasury Stock [Line Items]
Remaining authorized repurchase amount			$ 37.2
Subsequent Event [Member]
Equity, Class of Treasury Stock [Line Items]
Treasury stock, common, value	$ 15.7
Treasury stock, shares, acquired (in shares)	254,015
Treasury stock acquired, average cost per share (in dollars per share)	$ 62.01

Marketable Securities (Details)

Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	$ 3,197	$ 3,104
Available-for-sale Debt Securities, Amortized Cost Basis	$ 3,196	$ 3,103

Marketable Securities The matur

Marketable Securities The maturities of our marketable securities available for sale (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	$ 3,197	$ 3,104
Available-for-sale Debt Securities, Amortized Cost Basis	$ 3,196	$ 3,103
Certificates of Deposit [Member] | Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturities of marketable securites, by date	Apr. 10, 2018
Certificates of Deposit [Member] | Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturities of marketable securites, by date	Mar. 18, 2019

Marketable Securities Compositi

Marketable Securities Composition of Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	$ 3,197	$ 3,104
Available-for-sale Debt Securities, Amortized Cost Basis	$ 3,196	$ 3,103

Marketable Securities Fair Valu

Marketable Securities Fair Value of our Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Assets, Fair Value Disclosure, Recurring	$ 3,197	$ 3,104
Fair Value, Inputs, Level 1 [Member]
Schedule of Available-for-sale Securities [Line Items]
Assets, Fair Value Disclosure, Recurring	0	0
Fair Value, Inputs, Level 2 [Member]
Schedule of Available-for-sale Securities [Line Items]
Assets, Fair Value Disclosure, Recurring	3,197	3,104
Fair Value, Inputs, Level 3 [Member]
Schedule of Available-for-sale Securities [Line Items]
Assets, Fair Value Disclosure, Recurring	$ 0	$ 0

Derivative Financial Instrume70

Derivative Financial Instruments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2017
Derivative [Line Items]
Derivative, notional amount		$ 16.3
Gain (Loss) on Foreign Currency Cash Flow Hedge Ineffectiveness	$ 3.5

Derivative Financial Instrume71

Derivative Financial Instruments Gain (loss) on foreign currency exchange contracts (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Foreign Exchange [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ (750)	$ 39

Accounts and Other Receivable72

Accounts and Other Receivables Components of Accounts and Other Receivables (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts and Other Receivables, Net, Current	$ 116,900	$ 95,680	$ 87,429
Billed Revenues [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts and Other Receivables, Net, Current	107,190		87,429
Unbilled Revenues [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts and Other Receivables, Net, Current	$ 9,710		$ 0

Inventories Components of inven

Inventories Components of inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Parts and raw materials	$ 71,284		$ 58,567
Work in process	13,054		7,986
Finished goods	12,504		11,897
Inventory, Net	$ 96,842	$ 74,889	$ 78,450

Property and Equipment Details

Property and Equipment Details of property and equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 81,756	$ 85,183
Less: Accumulated depreciation	(61,050)	(67,388)
Property and equipment, net	20,706	17,795
Buildings and Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,846	1,788
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	37,886	36,579
Computer and Communication Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	25,391	26,819
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,479	1,568
Vehicles [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	273	341
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	14,156	17,286
Construction in Process [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 725	$ 802

Property and Equipment Deprecia

Property and Equipment Depreciation expense recorded in continuing operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 1,604	$ 1,025

Goodwill Schedule of the change

Goodwill Schedule of the changes in goodwill (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 53,812
Additions	110
Effect of Changes in Exchange Rates	984
Ending Balance	$ 54,906

Intangible Assets Schedule of o

Intangible Assets Schedule of other intangible assets (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 52,989	$ 51,359
Finite-Lived Intangible Assets, Accumulated Amortization	(19,544)	(17,860)
Finite-lived intangible assets, net	33,445	33,499
Technology-based [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	19,397	18,702
Finite-Lived Intangible Assets, Accumulated Amortization	(6,192)	(5,559)
Finite-lived intangible assets, net	13,205	13,143
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	30,885	30,034
Finite-Lived Intangible Assets, Accumulated Amortization	(11,763)	(10,787)
Finite-lived intangible assets, net	19,122	19,247
Trademarks and other [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	2,707	2,623
Finite-Lived Intangible Assets, Accumulated Amortization	(1,589)	(1,514)
Finite-lived intangible assets, net	$ 1,118	$ 1,109

Intangible Assets Schedule of a

Intangible Assets Schedule of amortization expense relating to other intangible assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 52,989		$ 51,359
Finite-Lived Intangible Assets, Accumulated Amortization	(19,544)		(17,860)
Finite-lived intangible assets, net	33,445		33,499
Amortization expense	1,257	$ 962
Technology Equipment [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	19,397		18,702
Finite-Lived Intangible Assets, Accumulated Amortization	(6,192)		(5,559)
Finite-lived intangible assets, net	$ 13,205		$ 13,143

Intangible Assets Schedule of F

Intangible Assets Schedule of Finite-Lived Intangible Assets, Future Amortization Expense (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
2016 (remaining)	$ 3,778
2,017	5,019
2,018	4,313
2,019	4,207
2,020	3,938
Thereafter	12,190
Finite-lived intangible assets, net	$ 33,445	$ 33,499

Warranties Narrative (Details)

Warranties Narrative (Details)	3 Months Ended
	Mar. 31, 2018
Minimum [Member]
Product Liability Contingency [Line Items]
Standard Product Warranty Term	12 months
Maximum [Member]
Product Liability Contingency [Line Items]
Standard Product Warranty Term	24 months

Warranties Changes in accrued p

Warranties Changes in accrued product warranties (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Movement in Standard Product Warranty Accrual [Roll Forward]
Balances at beginning of period	$ 2,312	$ 2,329
Standard and Extended Product Warranty Accrual, Additions from Business Acquisition	92	0
Increases to accruals related to sales during the period	178	2,181
Product Warranty Expense	(506)	(389)
Product Warranty Accrual, Foreign Exchange Impact	8	5
Balances at end of period	$ 2,084	$ 4,126

Pension Liability (Details)

Pension Liability (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	$ (20,490)		$ (19,797)
Defined Benefit Plan, Interest Cost	218	$ 264
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	(161)	(140)
Pension Cost (Reversal of Cost)	193	$ 194
Payments through April 30, 2024 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	900
Payments from May 1, 2024 through November 30, 2033 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 1,900

Pension Liability Net Periodic

Pension Liability Net Periodic Pension Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Postemployment Benefits [Abstract]
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	$ 161	$ 140
Defined Benefit Plan, Interest Cost	218	264
Defined Benefit Plan, Amortization of Gain (Loss)	136	70
Pension Cost (Reversal of Cost)	$ 193	$ 194

Pension Liability Net Pension L

Pension Liability Net Pension Liability (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	$ (20,490)	$ (19,797)

Stock-Based Compensation Schedu

Stock-Based Compensation Schedule of stock-based compensation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based compensation expense	$ 4,494	$ 3,398

Stock-Based Compensation Summar

Stock-Based Compensation Summary of stock option activity (Details) - Time Based [Member] - $ / shares shares in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	299	317
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 19.02	$ 18.97
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	(17)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 18.36
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period	(1)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	$ 12.19

Stock-Based Compensation Summ87

Stock-Based Compensation Summary of non-vested Restricted Stock Units activity (Details) - Restricted Stock Units (RSUs) [Member] - $ / shares shares in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 69.32
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 47.51
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	336	386
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	160
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	$ 52.59
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(155)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(55)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 59.64	$ 51.06

Stock-Based Compensation Narrat

Stock-Based Compensation Narrative (Details) shares in Millions	Mar. 31, 2018shares
2017 OMNIBUS Incentive Plan [Member] [Domain]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	2.7

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	Mar. 31, 2018USD ($)
Other Commitments [Line Items]
Purchase Commitment, Remaining Minimum Amount Committed	$ 177.4

Related Party Transactions (Det

Related Party Transactions (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)Companies	Mar. 31, 2017Companies	Dec. 31, 2017USD ($)
Related Party Transaction [Line Items]
Related Party Transactions, Number of Companies	1	1
Accounts Receivable, Related Parties | $	$ 7		$ 27
Management [Member]
Related Party Transaction [Line Items]
Related Party Transactions, Number of Companies	1	1

Related Party Transactions Sche

Related Party Transactions Schedule of related party transactions (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)Companies	Mar. 31, 2017USD ($)Companies	Dec. 31, 2017USD ($)
Related Party Transaction [Line Items]
Accounts Receivable, Related Parties | $	$ 7		$ 27
Sales - related parties | $	$ 73	$ 577
Related Party Transactions, Number of Companies | Companies	1	1
Management [Member]
Related Party Transaction [Line Items]
Related Party Transactions, Number of Companies | Companies	1	1

Geographic and Customer Infor92

Geographic and Customer Information Significant Customer Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Concentration Risk [Line Items]
Product	$ 171,209	$ 128,827
Applied Materials, Inc. [Member] | Sales Revenue, Goods, Net [Member]
Concentration Risk [Line Items]
Product	$ 69,872	$ 54,518
Concentration Risk, Percentage	35.70%	36.50%
Lam Research [Member] | Sales Revenue, Goods, Net [Member]
Concentration Risk [Line Items]
Product	$ 39,726	$ 32,016
Concentration Risk, Percentage	20.30%	21.40%
Accounts Receivable [Member] | Applied Materials, Inc. [Member] | Customer Concentration Risk [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	39.50%	42.00%
Concentration Risk, Amount	$ 46,131		$ 36,755
Accounts Receivable [Member] | Lam Research [Member] | Customer Concentration Risk [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	13.70%	6.20%
Concentration Risk, Amount	$ 15,957		$ 5,421

Credit Facility (Details)

Credit Facility (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)
Line of Credit Facility [Line Items]
Interest Expense	$ 0.1
Bank of America N.A. [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 150
Debt, Weighted Average Interest Rate	3.13%
Funded Debt To EBITDA Ratio	2
London Interbank Offered Rate (LIBOR) [Member] | Bank of America N.A. [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.25%
Funded Debt To EBITDA Ratio [Member] | Bank of America N.A. [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.75%