Advanced Energy Industries (AEIS) 10-K 2 Mar 20 2019 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Feb. 28, 2020	Jun. 28, 2019
Document and Entity Information
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2019
Entity File Number	000-26966
Entity Registrant Name	ADVANCED ENERGY INDUSTRIES INC
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	84-0846841
Entity Address, Address Line One	1595 Wynkoop Street, Suite 800, Denver
Entity Address, City or Town	Denver
Entity Address, State or Province	CO
Entity Address, Country	US
Entity Address, Postal Zip Code	80202
City Area Code	970
Local Phone Number	407-4670
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	AEIS
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		38,407,225
Entity Central Index Key	0000927003
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Public Float			$ 2,135,524,772

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 346,441	$ 349,301
Marketable securities	2,614	2,470
Accounts and other receivable, net of allowances of $7,745 and $1,856, respectively	246,564	100,442
Inventories	230,019	97,987
Income taxes receivable	4,245	2,220
Other current assets	36,825	10,173
Current assets from discontinued operations	30	5,855
Total current assets	866,738	568,448
Property and equipment, net	108,109	31,269
Operating lease right-of-use assets	105,404
Deposits and other assets	22,287	6,874
Goodwill	202,932	101,900
Intangible assets, net	184,011	54,910
Deferred income tax assets	42,656	47,099
Non-current assets from discontinued operations	269	5,984
TOTAL ASSETS	1,532,406	816,484
Current liabilities:
Accounts payable	170,671	39,646
Income taxes payable	9,687	13,258
Accrued payroll and employee benefits	51,545	21,775
Other accrued expenses	40,777	22,999
Customer deposits and other	10,926	7,345
Current portion of long-term debt	17,500
Current portion of operating lease liabilities	18,312
Current liabilities from discontinued operations	914	5,286
Total current liabilities	320,332	110,309
Long-term debt	321,527
Operating lease liabilities	90,538
Pension benefits	68,169	19,407
Deferred income tax liabilities	9,952	6,988
Uncertain tax positions	16,055	14,318
Long-term deferred revenue	8,011	29,108
Other long-term liabilities	19,675	18,337
Non-current liabilities from discontinued operations	887	10,715
Total liabilities	855,146	209,182
Commitments and contingencies (Note 19)
Stockholders' equity:
Preferred stock, $0.001 par value, 1,000 shares authorized, none issued and outstanding
Common stock, $0.001 par value, 70,000 shares authorized; 38,358 and 38,164 issued and outstanding, respectively	38	38
Additional paid-in capital	104,849	97,418
Accumulated other comprehensive loss	(5,897)	(3,449)
Retained earnings	577,724	512,783
Advanced Energy stockholders' equity	676,714	606,790
Noncontrolling interest	546	512
Total stockholders' equity	677,260	607,302
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 1,532,406	$ 816,484

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Consolidated Balance Sheets
Accounts receivable, allowances	$ 7,745	$ 1,856
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	0
Preferred stock, shares outstanding	0	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)	38,358,000	38,164,000
Common stock, shares outstanding (in shares)	38,358,000	38,164,000

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Total sales, net	$ 788,948	$ 718,892	$ 671,012
Total cost of sales	473,296	353,285	314,631
Gross profit	315,652	365,607	356,381
Operating expenses:
Research and development	101,503	76,008	57,999
Selling, general and administrative	142,555	108,033	93,262
Amortization of intangible assets	12,168	5,774	4,350
Restructuring expense	5,038	4,239
Total operating expenses	261,264	194,054	155,611
Operating income	54,388	171,553	200,770
Other income (expense), net	12,806	823	(2,579)
Income from continuing operations, before income taxes	67,194	172,376	198,191
Provision for income taxes	10,699	25,227	62,090
Income from continuing operations	56,495	147,149	136,101
Income (loss) from discontinued operations, net of income taxes	8,480	(38)	1,760
Net income	64,975	147,111	137,861
Income from continuing operations attributable to noncontrolling interest	34	86
Net income attributable to Advanced Energy Industries, Inc.	$ 64,941	$ 147,025	$ 137,861
Basic weighted-average common shares outstanding	38,281	39,081	39,754
Diluted weighted-average common shares outstanding	38,495	39,352	40,176
Earnings per share:
Continuing operations: Basic earnings per share	$ 1.47	$ 3.76	$ 3.42
Continuing operations: Diluted earnings per share	1.47	3.74	3.39
Discontinued operations: Basic earnings per share	0.22		0.04
Discontinued operations: Diluted earnings per share	0.22		0.04
Net income:
Basic earnings per share	1.70	3.76	3.47
Diluted earnings per share	$ 1.69	$ 3.74	$ 3.43
Product [Member]
Total sales, net	$ 678,061	$ 610,326	$ 578,650
Total cost of sales	416,976	298,597	267,587
Service [Member]
Total sales, net	110,887	108,566	92,362
Total cost of sales	$ 56,320	$ 54,688	$ 47,044

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Consolidated Statements of Comprehensive Income
Net income	$ 64,975	$ 147,111	$ 137,861
Other comprehensive income, net of income taxes
Foreign currency translation	(2,523)	(5,285)	8,305
Unrealized loss on marketable securities			(2)
Minimum benefit retirement liability	75	(697)	1,163
Comprehensive income	62,527	141,129	147,327
Comprehensive income attributable to noncontrolling interest	34	86
Comprehensive income attributable to Advanced Energy Industries, Inc.	$ 62,493	$ 141,043	$ 147,327

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Foreign Currency Translation	Unrealized Gain (Loss)on Marketable Securities	Minimum Benefit Retirement Liability	Retained Earnings	Non-controlling Interest	Total
Beginning Balance at Dec. 31, 2016	$ 40	$ 203,603	$ (3,610)	$ 2	$ (3,325)	$ 195,364		$ 392,074
Beginning Balance (in shares) at Dec. 31, 2016	39,712,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock issued from equity plans		(1,316)						(1,316)
Stock issued from equity plans (in shares)	314,000
Stock-based compensation		12,549						12,549
Stock buyback		(29,993)						(29,993)
Stock buyback (in shares)	(422,000)
Foreign currency translation			8,305					8,305
Unrealized loss on marketable securities				(2)				(2)
Minimum benefit retirement liability					1,163			1,163
Net income						137,861		137,861
Comprehensive income			8,305	$ (2)	1,163	137,861		147,327
Ending Balance at Dec. 31, 2017	$ 40	184,843	4,695		(2,162)	333,225		520,641
Ending Balance (in shares) at Dec. 31, 2017	39,604,000
Adoption of new accounting standards						32,533		32,533
Non-controlling interest from acquisition							$ 426	426
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock issued from equity plans		(2,005)						(2,005)
Stock issued from equity plans (in shares)	256,000
Stock-based compensation		9,703						9,703
Stock buyback	$ (2)	(95,123)						(95,125)
Stock buyback (in shares)	(1,696,000)
Foreign currency translation			(5,285)					(5,285)
Minimum benefit retirement liability					(697)			(697)
Net income						147,025	86	147,111
Comprehensive income			(5,285)		(697)	147,025	86	141,129
Ending Balance at Dec. 31, 2018	$ 38	97,418	(590)		(2,859)	512,783	512	$ 607,302
Ending Balance (in shares) at Dec. 31, 2018	38,164,000							38,164,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock issued from equity plans		104						$ 104
Stock issued from equity plans (in shares)	194,000
Stock-based compensation		7,327						7,327
Foreign currency translation			(2,523)					(2,523)
Minimum benefit retirement liability					75			75
Net income						64,941	34	64,975
Comprehensive income			(2,523)		75	64,941	34	62,527
Ending Balance at Dec. 31, 2019	$ 38	$ 104,849	$ (3,113)		$ (2,784)	$ 577,724	$ 546	$ 677,260
Ending Balance (in shares) at Dec. 31, 2019	38,358,000							38,358,000

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 64,975	$ 147,111	$ 137,861
Income (loss) from discontinued operations, net of income taxes	8,480	(38)	1,760
Income (loss) from continuing operations, net of income taxes	56,495	147,149	136,101
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	26,147	13,592	9,424
Stock-based compensation expense	7,327	9,703	12,549
Provision for deferred income taxes	1,015	5,618	28,765
Loss on foreign exchange hedge			3,489
Discounts on notes receivable	1,100
Gain on sale of central inverter service business	(14,795)
Net loss on disposal of assets	700	481	122
Changes in operating assets and liabilities, net of assets acquired:
Accounts and other receivable, net	(18,879)	3,445	(7,497)
Inventories	3,687	(11,276)	(19,261)
Other assets	23,544	(2,975)	(1,030)
Accounts payable	(16,094)	(12,618)	1,812
Other liabilities and accrued expenses	(12,486)	(3,239)	7,159
Income taxes	(9,862)	1,547	18,323
Net cash provided by (used in) operating activities from continuing operations	47,899	151,427	189,956
Net cash provided by (used in) operating activities from discontinued operations	493	(156)	(7,255)
Net cash provided by operating activities	48,392	151,271	182,701
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of marketable securities		(95)	(107)
Proceeds from sale of marketable securities	1,742	589	1,903
Acquisitions, net of cash acquired	(366,101)	(93,756)	(17,347)
Issuance of notes receivable	(4,300)
Purchase of foreign exchange hedge			(3,489)
Purchases of property and equipment	(25,188)	(20,330)	(9,042)
Net cash provided by (used in) investing activities from continuing operations	(393,847)	(113,592)	(28,082)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from long-term borrowings	347,486
Payments on long-term borrowings	(8,750)
Purchase and retirement of common stock		(95,125)	(29,993)
Net payments related to stock-based award activities	104	(2,009)	(1,314)
Net cash provided by (used in) financing activities from continuing operations	338,840	(97,134)	(31,307)
EFFECT OF CURRENCY TRANSLATION ON CASH	(1,496)	(1,030)	2,208
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(8,111)	(60,485)	125,520
CASH AND CASH EQUIVALENTS, beginning of period	354,552	415,037	289,517
CASH AND CASH EQUIVALENTS, end of period	346,441	354,552	415,037
Less cash and cash equivalents from discontinued operations		5,251	7,754
CASH AND CASH EQUIVALENTS FROM CONTINUING OPERATIONS, end of period	346,441	349,301	407,283
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash paid for interest	3,479	228	66
Cash paid for income taxes	18,594	16,190	5,314
Cash received for refunds of income taxes	$ 1,762	$ 1,135	$ 1,448

Operations and Summary of Signi

Operations and Summary of Significant Accounting Policies and Estimates	12 Months Ended
	Dec. 31, 2019
Operations and Summary of Significant Accounting Policies and Estimates
OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND ESTIMATES	NOTE 1. OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND ESTIMATES 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, refine, and modify the raw electrical power from the utility and convert it into various types of highly-controllable usable power that is predictable, repeatable and customizable. We operate in a single segment structure for power electronics conversion products and we operate in four vertical markets or applications to enable tracking of market trends. Our power solutions enable innovation in complex semiconductor and thin film plasma processes such as dry etch, strip, chemical and physical deposition, high and low voltage applications such as process control, computing, networking, telecommunication, analytical instrumentation, medical equipment, industrial technology and temperature-critical thermal applications such as material and chemical processing. We also supply related instrumentation products for advanced temperature measurement and control, electrostatic instrumentation products for test and measurement applications, and gas sensing and monitoring solutions for multiple industrial markets. Our network of global service support centers provides local repair and field service capability in key regions as well as provide upgrades and refurbishment services, and sales of used equipment to businesses that use our products. As of December 31, 2015, we discontinued our Inverter production, engineering, and sales product line. As such, all Inverter revenues, costs, assets and liabilities are reported in Discontinued Operations for all periods presented herein. See Note 4. Disposed and Discontinued Operations Principles of Consolidation Use of Estimates in the Preparation of the Consolidated Financial Statements — Foreign Currency Translation — The functional currency of certain of our foreign subsidiaries is the local currency. Assets and liabilities of these foreign subsidiaries are translated to the United States dollar at prevailing exchange rates at the balance sheet date; revenues and expenses are translated at the average exchange rates in effect for each period. Translation adjustments resulting from this process are reported as a separate component of Other Comprehensive Income. For certain other subsidiaries the functional currency is the US Dollar. Foreign currency transactions are recorded based on exchange rates at the time such transactions arise. Subsequent changes in exchange rates for foreign currency denominated monetary assets and liabilities result in foreign currency transaction gains and losses which are reflected as unrealized (based on period end remeasurement) or realized (upon settlement of the transactions) in other income, net in our Consolidated Statements of Operations. ​ Fair Value — U.S. GAAP for fair value establishes a hierarchy that prioritizes fair value measurements based on the types of inputs used for the various valuation techniques (market approach, income approach, and cost approach). The Company’s financial assets and liabilities are measured using inputs from the three levels of the fair value hierarchy. The three levels of the hierarchy and the related inputs are as follows: ● Level 1 — Quoted prices (unadjusted) in active markets for identical assets or liabilities that the entity can access at the measurement date. ● Level 2 — Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. ● Level 3 — Unobservable inputs for the asset or liability. The Company categorizes fair value measurements within the fair value hierarchy based upon the lowest level of the most significant inputs used to determine fair value. The carrying amounts of our cash and cash equivalents, accounts receivable, accounts payable and other current assets and liabilities approximate fair value as recorded due to the short-term nature of these instruments. The fair value of derivatives is estimated utilizing observable foreign exchange rates adjusted for non-performance credit risk associated with our counterparties. The fair value of contingent consideration and other acquired assets and liabilities associated with the acquisition of Artesyn, are based on Level 3 inputs. There were transfers Note 8 Derivative Financial Instruments Note 22, Credit Facility The Company’s non-financial assets, which primarily consist of property and equipment, goodwill, and other intangible assets, are not required to be carried at fair value on a recurring basis and are reported at carrying value. However, on a periodic basis or whenever events or changes in circumstances indicate that their carrying value may not be fully recoverable (and at least annually for goodwill and indefinite-lived intangible assets), non-financial instruments are assessed for impairment and, if applicable, written down to and recorded at fair value. See Note 12. Goodwill Note 13. Intangible Assets Cash, Cash Equivalents, and Marketable Securities Sometimes we invest excess cash in money market funds not insured by the Federal Deposit Insurance Corporation. We believe that the investments in money market funds are on deposit with credit-worthy financial institutions and that the funds are highly liquid. The investments in money market funds are reported at fair value, with interest income recorded in earnings and are included in “Cash and cash equivalents.” Concentrations of Credit Risk — We have established an allowance for doubtful accounts based upon factors surrounding the credit risk of specific customers, historical trends, and other information. Accounts Receivable and Allowance for Doubtful Accounts — Changes in allowance for doubtful accounts are summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 Balances at beginning of period ​ $ 1,856 ​ $ 1,748 Additions from acquisition ​ ​ 1,884 ​ ​ 416 Additions - charged to expense ​ 4,207 ​ 109 Deductions - write-offs, net of recoveries ​ (202) ​ (417) Balances at end of period ​ $ 7,745 ​ $ 1,856 ​ Inventories We regularly review inventory quantities on hand and record a provision to write-down excess and obsolete inventory to its estimated net realizable value, if less than cost, based primarily on historical usage and our estimated forecast of product demand. Demand for our products can fluctuate significantly. A significant decrease in demand could result in an increase in the charges for excess inventory quantities on hand. In addition, our industry is subject to technological change, new product development, and product technological obsolescence that could result in an increase in the amount of obsolete inventory quantities on hand. Therefore, any significant unanticipated changes in demand or technological developments could have a significant impact on the value of our inventory and our reported operating results. Property and Equipment 3 Amortization of leasehold improvements is calculated using the straight-line method over the lease term or the estimated useful life of the assets, whichever period is shorter. Leasehold additions and improvements are capitalized, while maintenance and repairs are expensed as incurred. When depreciable assets are retired, or otherwise disposed of, the cost and related accumulated depreciation are removed from the accounts and any related gains or losses are included in other income, net, in our Consolidated Statements of Operations. Purchase accounting Intangible Assets, Goodwill and Other Long-Lived Assets The estimation of useful lives and expected cash flows requires us to make judgments regarding future periods that are subject to some factors outside of our control. Changes in these estimates can result in revisions to our carrying value of these assets and may result in material charges to our results of operations. The annual impairment test for goodwill can be performed using an assessment of qualitative factors in determining if it is more likely than not that goodwill is impaired. If this assessment indicates that it is more likely than not that goodwill is impaired, the next step of impairment testing compares the fair value of a reporting unit to its carrying value. Goodwill would be impaired if the resulting implied fair value of goodwill was less than the recorded carrying value of the goodwill. Debt Issuance Costs Note 22. Credit Facility Revenue Recognition We maintain a worldwide support organization in 10 countries, including the United States, the PRC, Japan, Korea, Taiwan, Germany, Ireland, Singapore, Israel and Great Britain. 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. As part of our ongoing service business, we satisfy our service obligations under extended warranties and preventive maintenance contracts. Extended warranties had previously been offered on our discontinued inverter products. Any up-front fees received for extended warranties or maintenance plans are deferred and recognized ratably over the service periods, as defined in the agreements. Research and Development Expenses Warranty Costs 12 five Note 4. Disposed and Discontinued Operations Note 15. Warranties Stock-Based Compensation Income Taxes We assess the recoverability of our net deferred tax assets and the need for a valuation allowance on a quarterly basis. Our assessment includes a number of factors including historical results and taxable income projections for each jurisdiction. The ultimate realization of deferred income tax assets is dependent on the generation of taxable income in appropriate jurisdictions during the periods in which those temporary differences are deductible. We consider the scheduled reversal of deferred income tax liabilities, projected future taxable income, and tax planning strategies in determining the amount of the valuation allowance. Based on the level of historical taxable income and projections for future taxable income over the periods in which the deferred income tax assets are deductible, we determine if we will realize the benefits of these deductible differences. Accounting for income taxes requires a two-step approach to recognize and measure uncertain tax positions. In general, we are subject to regular examination of our income tax returns by the Internal Revenue Service and other tax authorities. The first step is to evaluate the tax position for recognition by determining, if based on the technical merits, it is more likely than not that the position will be sustained upon audit, including resolutions of related appeals or litigation processes, if any. The second step is to measure the tax benefit as the largest amount that is more than 50% likely of being realized upon ultimate settlement. We regularly assess the likelihood of favorable or unfavorable outcomes resulting from these examinations to determine the adequacy of our provision for income taxes. This evaluation is based on factors including, but not limited to, changes in facts or circumstances, changes in tax law, effectively settled issues under audit, and new audit activity. On December 22, 2017, the Tax Act was enacted into law and the new legislation contains several key tax provisions that affected us, including a one-time mandatory transition tax on accumulated foreign earnings and a reduction of the corporate income tax rate to 21%, among others. In conjunction with the Tax Act enactment, the SEC issued Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act Leases — Right-of-use assets and operating lease liabilities are recognized at the present value of the future lease payments at the lease commencement date. The interest rate used to determine the present value of the future lease payments is our incremental borrowing rate, because the interest rate implicit in our leases is not readily determinable. Our incremental borrowing rate is estimated to approximate the interest rate on a collateralized basis with similar terms and payments. Our lease terms include periods under options to extend or terminate the lease when it is reasonably certain that we will exercise that option. Right-of-use assets also include any prepaid lease payments and lease incentives. Operating lease expense is recognized on a straight-line basis over the lease term. Commitments and Contingencies these uncertainties in a manner inconsistent with our expectations could have a significant impact on our results of operations and financial condition NEW ACCOUNTING STANDARDS New Accounting Standards Adopted 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 the Tax Act to retained earnings. ASU 2018-02 is effective for fiscal years beginning after December 15, 2018, including interim periods within those years. We adopted ASU 2018-02 during the first quarter of fiscal year 2019 which did not materially impact our Consolidated Financial Statements. In June 2018, the FASB issued ASU 2018-07, "Compensation-Stock Compensation (Topic 718)", Improvements to Non-employee Share-based Payments (“ASU 2018-07”). This ASU expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from non-employees. ASU 2018-07 is effective for fiscal years beginning after December 15, 2018. The new guidance is required to be applied retrospectively with the cumulative effect recognized at the date of initial application. We adopted ASU 2018-07 during the first quarter of fiscal year 2019 which did not materially impact our Consolidated Financial Statements. In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842),” to increase transparency and comparability among organizations by recognizing lease right-of-use 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. We adopted ASU 2016-02 using the modified retrospective approach and recorded $38.2 million of operating lease right-of-use assets and $38.4 million of operating lease liabilities 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. 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. New Accounting Standards In June 2016, the FASB issued ASU 2016-13, "Financial Instruments—Credit Losses (Topic 326)", Measurement of Credit Losses on Financial Instruments ("ASU 2016-13"). This ASU changes the methodology for measuring credit losses on financial instruments and the timing of when such losses are recorded. ASU 2016-13 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2019. Early adoption is permitted for fiscal years, and interim periods within those years, beginning after December 15, 2018. We are currently assessing the impact ASU 2016-13 will have on our Consolidated Financial Statements. In August 2018, the FASB issued ASU 2018-13, "Fair Value Measurement (Topic 820)" ("ASU 2018-13"). ASU 2018-13 modifies the disclosure requirements on fair value measurements in Topic 820, Fair Value Measurement, based on the concepts in the Concepts Statement, including the consideration of costs and benefits. ASU 2018-13 is effective for fiscal years ending after December 15, 2019 and shall be applied to all periods presented on a retrospective basis. Early adoption is permitted. We are currently assessing and do not believe ASU 2018-13 will have a significant impact on our fair value measurements disclosure requirements. In August 2018, the FASB issued ASU 2018-14, "Compensation—Retirement Benefits—Defined Benefit Plans—General (Subtopic 715-20)" ("ASU 2018-14"). ASU 2018-14 eliminates requirements for certain disclosures and requires additional disclosures under defined benefit pension plans and other post-retirement plans. ASU 2018-14 is effective for fiscal years ending after December 15, 2020 and shall be applied to all periods presented on a retrospective basis. Early adoption is permitted. We are currently assessing and do not believe ASU 2018-14 will have a significant impact on our defined benefit plan disclosure requirements. ​ In December 2019, the FASB issued authoritative guidance intended to simplify the accounting for income taxes (ASU 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes”). This guidance eliminates certain exceptions to the general approach to the income tax accounting model, and adds new guidance to reduce the complexity in accounting for income taxes. This guidance is effective for annual periods after December 15, 2020, including interim periods within those annual periods. We are currently evaluating the potential impact of this guidance on our financial statements.

Business Acquisitions

Business Acquisitions	12 Months Ended
	Dec. 31, 2019
Business Acquisitions
BUSINESS ACQUISITIONS	NOTE 2. BUSINESS ACQUISITIONS 2019 Acquisitions In September 2019, we completed the acquisition of Artesyn pursuant to the Stock Purchase Agreement (“Acquisition Agreement”), as amended, dated May 14, 2019. Pursuant to the Acquisition Agreement, we acquired all of Artesyn’s issued and outstanding shares for a preliminary purchase price of $361.3 million, net of cash acquired, including the assumption of certain liabilities and subject to an adjustment for net working capital. The purchase price included the contingent consideration related to a potential payment back to the seller per the Acquisition Agreement for any tax benefit arising from the utilization of acquired net operating losses through 2021 at the federal income tax rate of 21.0%. The amount recorded represents our best estimate of the present value of the tax benefit we will achieve utilizing the acquired net operating losses through 2021. In connection with the Acquisition Agreement, we entered into a credit agreement that provided us with aggregate financing of Note 22. Credit Facility Artesyn’s Embedded Power business is one of the world’s largest providers of highly engineered, application-specific power supplies for demanding applications. This acquisition will diversify our product portfolio and give us access to additional growth markets, including hyperscale data centers, telecom infrastructure in next generation 5G networks, embedded industrial power applications and medical power for diagnostic and treatment applications. The components of the fair value of the total consideration transferred for the acquisition is as follows: ​ ​ ​ ​ ​ ​ ​ Cash paid for acquisition ​ $ 389,326 Non-cash consideration ​ 2,000 Contingent consideration and working capital adjustments ​ ​ (6,848) Total fair value of consideration transferred ​ ​ 384,478 Less cash acquired ​ (23,225) Total purchase price ​ $ 361,253 ​ The following table summarizes the estimated preliminary fair values of the assets acquired and liabilities assumed from the acquisition in 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Preliminary: September 10, 2019 ​ Measurement Period Adjustments ​ Preliminary: December 31, 2019 Accounts and other receivable, net ​ $ 128,221 ​ $ - ​ $ 128,221 Inventories ​ 140,678 ​ ​ (900) ​ ​ 139,778 Property and equipment ​ 65,016 ​ ​ (1,984) ​ ​ 63,032 Operating lease right-of-use assets ​ ​ 60,217 ​ ​ (144) ​ ​ 60,073 Goodwill ​ 143,262 ​ ​ (30,222) ​ ​ 113,040 Intangible assets ​ 125,000 ​ ​ (1,000) ​ ​ 124,000 Deferred income tax assets ​ 14,767 ​ ​ (14,767) ​ ​ — Other assets ​ 61,511 ​ ​ 2,507 ​ ​ 64,018 Total assets acquired ​ 738,672 ​ ​ (46,510) ​ ​ 692,162 Accounts payable ​ 144,652 ​ ​ 50 ​ ​ 144,702 Operating lease liability ​ ​ 59,634 ​ ​ 477 ​ ​ 60,111 Pension liability ​ ​ 48,494 ​ ​ 192 ​ ​ 48,686 Deferred income tax liabilities ​ 37,218 ​ ​ (31,372) ​ ​ 5,846 Other liabilities ​ 80,876 ​ ​ (9,312) ​ ​ 71,564 Total liabilities assumed ​ 370,874 ​ ​ (39,965) ​ ​ 330,909 Total fair value of net assets acquired ​ $ 367,798 ​ $ (6,545) ​ $ 361,253 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization ​ ​ ​ Artesyn ​ Method ​ Useful Life Technology ​ $ 28,000 ​ Straight-line 5 Customer relationships ​ 75,000 ​ Straight-line 15 Tradename ​ 21,000 ​ Straight-line 10 Total ​ $ 124,000 ​ ​ 2018 Acquisitions In September 2018, Advanced Energy acquired LumaSense Technologies Holdings, Inc. ("LumaSense"), a privately held company with primary operations in Santa Clara, California, Frankfurt, Germany, and Ballerup, Denmark for a purchase price of $84.7 million, net of cash acquired. In May 2018, Advanced Energy acquired the electrostatic technology and product line (“Electrostatic Product Line”) from Monroe Electronics, Inc. ("Monroe"), a privately held electronics manufacturer in Lyndonville, New York for $3.0 million in cash. In February 2018, Advanced Energy acquired Trek Holding Co., LTD ("Trek"), a privately held company with operations in Tokyo, Japan and Lockport, New York, for $6.1 million, net of cash acquired. 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 our 2018 acquisitions are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Electrostatic ​ ​ ​ ​ ​ ​ Trek ​ Product Line ​ LumaSense ​ Total Cash paid for acquisition ​ $ 11,723 ​ $ 3,000 ​ $ 94,946 ​ $ 109,669 Less cash acquired ​ (5,651) ​ — ​ (10,262) ​ (15,913) Total purchase price ​ $ 6,072 ​ $ 3,000 ​ $ 84,684 ​ $ 93,756 ​ In 2019, Advanced Energy finalized the assessment of fair value for the assets acquired and liabilities assumed related to the LumaSense acquisition. The following table summarizes the fair values of the assets acquired and liabilities assumed from the LumaSense acquisition, including measurement period adjustments. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Preliminary: December 31, 2018 ​ Measurement Period Adjustments ​ Adjusted: December 31, 2019 Accounts and other receivable, net ​ $ 7,167 ​ $ - ​ $ 7,167 Inventories ​ 9,372 ​ ​ - ​ ​ 9,372 Property and equipment ​ 1,353 ​ ​ - ​ ​ 1,353 Goodwill ​ 48,032 ​ ​ (11,774) ​ ​ 36,258 Intangible assets ​ 26,000 ​ ​ 17,240 ​ ​ 43,240 Deferred income tax assets ​ 8,116 ​ ​ (1,785) ​ ​ 6,331 Other assets ​ 5,126 ​ ​ 878 ​ ​ 6,004 Total assets acquired ​ 105,166 ​ ​ 4,559 ​ ​ 109,725 Accounts payable ​ 5,734 ​ ​ - ​ ​ 5,734 Deferred income tax liabilities ​ 7,984 ​ ​ 3,715 ​ ​ 11,699 Other liabilities ​ 6,764 ​ ​ 844 ​ ​ 7,608 Total liabilities assumed ​ 20,482 ​ ​ 4,559 ​ ​ 25,041 Total fair value of net assets acquired ​ $ 84,684 ​ $ - ​ $ 84,684 ​ During 2019, we adjusted the estimated values of the assets acquired and liabilities assumed based upon the final valuation report. These adjustments included additional liabilities, changes to deferred taxes and changes in the allocation of excess purchase price between goodwill and intangibles. ​ The final fair values of the assets acquired and liabilities assumed from our acquisitions in 2018 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Electrostatic ​ ​ ​ ​ ​ ​ Trek ​ Product Line ​ LumaSense ​ Total Accounts and other receivable, net ​ $ 2,818 ​ $ 77 ​ $ 7,167 ​ $ 10,062 Inventories ​ 3,941 ​ 292 ​ 9,372 ​ 13,605 Property and equipment ​ 594 ​ 50 ​ 1,353 ​ 1,997 Goodwill ​ — ​ 1,220 ​ 36,258 ​ 37,478 Intangible assets ​ 788 ​ 1,400 ​ 43,240 ​ 45,428 Deferred income tax assets ​ 606 ​ — ​ 6,331 ​ 6,937 Other assets ​ 854 ​ — ​ 6,004 ​ 6,858 Total assets acquired ​ 9,601 ​ 3,039 ​ 109,725 ​ 122,365 Accounts payable ​ 747 ​ 39 ​ 5,734 ​ 6,520 Deferred income tax liabilities ​ — ​ — ​ 11,699 ​ 11,699 Other liabilities ​ 2,782 ​ — ​ 7,608 ​ 10,390 Total liabilities assumed ​ 3,529 ​ 39 ​ 25,041 ​ 28,609 Total fair value of net assets acquired ​ $ 6,072 ​ $ 3,000 ​ $ 84,684 ​ $ 93,756 ​ A summary of the intangible assets acquired in 2018, amortization method and estimated useful lives are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Method and Useful life ​ ​ ​ ​ Electrostatic ​ ​ ​ Amortization ​ ​ ​ Trek ​ Product Line ​ LumaSense ​ Method ​ Useful Life Technology ​ $ 671 ​ $ 1,200 ​ $ 35,530 ​ Straight-line 10 - 15 Customer relationships ​ 117 ​ 200 ​ 4,360 ​ Straight-line 10 Tradename ​ — ​ — ​ 3,350 ​ Straight-line 10 Total ​ $ 788 ​ $ 1,400 ​ $ 43,240 ​ ​ ​ ​ ​ 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. The goodwill represents expected operating synergies from combining operations with the acquired companies and the estimated value associated with the enhancements to our comprehensive product lines. Pro forma results for Advanced Energy Inc. giving effect to the Artesyn Embedded Power Business and LumaSense Technologies Holdings, Inc. Transactions The following unaudited pro forma financial information presents the combined results of operations of Advanced Energy, LumaSense and Artesyn as if each of the acquisitions had been completed at the beginning of the fiscal year prior to their acquisition. The unaudited pro forma financial information is presented for informational purposes and is not indicative of the results of operations that would have been achieved if the acquisitions had taken place at the beginning of the year prior to the acquisition dates, nor are they indicative of future results. The unaudited pro forma financial information for the year ended December 31, 2019 includes Advanced Energy’s results, including the post-acquisition results of LumaSense, since September 1, 2018 and the post-acquisition results of Artesyn, since September 10, 2019. The unaudited pro forma financial information for the year ended December 31, 2019 and 2018 combines Advanced Energy’s results with the pre-acquisition results of Artesyn and LumaSense for that period. ​ The following table presents our unaudited pro forma results for the acquisitions of Artesyn and LumaSense: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2019 ​ 2018 ​ ​ As Reported Pro Forma As Reported Pro Forma Total sales ​ $ 788,948 $ 1,202,790 $ 718,892 $ 1,350,037 Net income attributable to Advanced Energy Industries, Inc. ​ $ 64,941 $ 83,104 $ 147,025 $ 158,422 Earnings per share: ​ ​ ​ ​ ​ Basic earnings per share ​ $ 1.70 ​ $ 2.17 ​ $ 3.76 ​ $ 4.05 Diluted earnings per share ​ $ 1.69 ​ $ 2.16 ​ $ 3.74 ​ $ 4.03 ​ The unaudited pro forma results for all periods presented include adjustments made to account for certain costs and transactions that would have been incurred had the acquisitions been completed at the beginning of the year prior to the year of acquisition. These include adjustments to amortization charges for acquired intangible assets, interest and financing expenses, transaction costs, amortization of purchased gross profit and the alignment of various accounting policies. These adjustments are net of any applicable tax impact and were included to arrive at the pro forma results above. Artesyn’s operating results have been included in the Advanced Energy’s operating results for the periods subsequent to the completion of the acquisition on September 10, 2019. During the year ended December 31, 2019, Artesyn contributed total sales of $220.3 million and net income of $7.1 million, including interest and other expense associated with the financing of the transaction.

Revenue

Revenue	12 Months Ended
	Dec. 31, 2019
Revenue
REVENUE	NOTE 3. REVENUE Revenue Recognition We recognize revenue when we have satisfied our performance obligations which typically occurs when control of the products or services have been transferred 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. 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 technology applications. We also supply thermal instrumentation products for advanced temperature measurement and control in these markets. As a result of the Artesyn acquisition, we now sell precision power conversion products into the telecom and networking, data center, and additional medical and industrial 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 our products. We principally serve original equipment manufacturers ("OEM") and end customers in the semiconductor, flat panel display, high voltage, solar panel, telecom and networking, data center, medical, and other industrial capital equipment markets. Our advanced power 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. Our embedded power products are used in a wide range of applications, including 5G, datacenter including hyperscale and other industrial and medical applications. Services Our global support services group offers warranty and after-market 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 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, Singapore 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. We record a contract liability for payments received for extended warranties or maintenance plans for which we have not yet provided the services. Revenue under these arrangements is recognized ratably over the underlying terms as we do not have historical information which would allow us to project the estimated service usage pattern at this time. ​ In May 2019, we sold our grid-tied central inverter repair and service operation to a third party. In connection with this sale, approximately $22.0 million of deferred revenue related to extended warranties and service contracts, were transferred to the buyer. See Note 4. Disposed and Discontinued Operations ​ Disaggregation of Revenue The following table presents our sales by product line, which includes certain reclassifications to prior comparative periods to conform to our current year presentation: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 ​ 2017 ​ Semiconductor Equipment ​ $ 403,018 ​ $ 533,770 ​ $ 554,063 ​ Industrial & Medical ​ 245,992 ​ 185,122 ​ 116,949 ​ Data Center Computing ​ ​ 91,438 ​ ​ — ​ ​ — ​ Telecom & Networking ​ ​ 48,500 ​ ​ — ​ ​ — Total ​ $ 788,948 ​ $ 718,892 ​ $ 671,012 ​ ​ ​ The following table presents our sales by geographic region: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 North America ​ $ 373,634 47.4 % $ 372,834 51.8 % $ 377,347 56.2 % Asia ​ 295,155 37.4 ​ 250,574 34.9 ​ 221,690 33.1 ​ Europe ​ 119,427 15.1 ​ 94,793 13.2 ​ 71,796 10.7 ​ Other ​ 732 0.1 ​ 691 0.1 ​ 179 — ​ Total ​ $ 788,948 100.0 % $ 718,892 100.0 % $ 671,012 100.0 % ​ 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: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Product and service revenue recognized at point in time ​ $ 786,918 ​ $ 715,055 ​ $ 667,440 Extended warranty and service contracts recognized over time ​ 2,030 ​ 3,837 ​ 3,572 Total ​ $ 788,948 ​ $ 718,892 ​ $ 671,012 ​

Disposed and Discontinued Opera

Disposed and Discontinued Operations	12 Months Ended
	Dec. 31, 2019
Disposed and Discontinued Operations
DISPOSED AND DISCONTINUED OPERATIONS	NOTE 4. DISPOSED AND DISCONTINUED OPERATIONS Disposed Operations In May 2019, we sold our grid-tied central solar inverter services business to Bold Renewables Holdings, LLC (“Buyer”) for $1.00 dollar and assumption of our initial product warranty and our extended warranty service obligations. In connection with this transaction, we entered into a Loan and Security Agreement with the Buyer. Under this agreement, we initially loaned $2.8 million to the buyer at closing and loaned an additional $1.5 million in the fourth quarter of 2019. We have made available an additional $3.75 million that may be borrowed in the future, subject to certain operating and liquidity covenants, for operating needs over the next ten years. The borrowings under the Loan and Security Agreement bear interest at 0% for the first 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 (loss) 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 (loss) from discontinued operations, net of income taxes" are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 Sales ​ $ — ​ $ — Cost of sales ​ (901) ​ (88) Total operating expense ​ 1,022 ​ 96 Operating income (loss) from discontinued operations ​ (121) ​ (8) Other income (expense) ​ 10,895 ​ (24) Income (loss) from discontinued operations before income taxes ​ 10,774 ​ (32) Provision (benefit) for income taxes ​ 2,294 ​ 6 Income (loss) from discontinued operations, net of income taxes ​ $ 8,480 ​ $ (38) ​ Assets and Liabilities of discontinued operations within the Consolidated Balance Sheets are comprised of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2019 2018 Cash and cash equivalents ​ $ — ​ $ 5,251 Accounts and other receivables, net ​ ​ — ​ ​ 406 Inventories ​ ​ 30 ​ ​ 198 Current assets of discontinued operations ​ ​ 30 ​ ​ 5,855 Other assets ​ ​ — ​ ​ 67 Deferred income tax assets ​ 269 ​ 5,917 Non-current assets of discontinued operations ​ ​ 269 ​ ​ 5,984 Accounts payable and other accrued expenses ​ ​ — ​ ​ 350 Accrued warranty ​ 914 ​ 4,936 Current liabilities of discontinued operations ​ ​ 914 ​ ​ 5,286 Accrued warranty ​ ​ 698 ​ ​ 10,429 Other liabilities ​ 189 ​ 286 Non-current liabilities of discontinued operations ​ $ 887 ​ $ 10,715 ​

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2019
Income Taxes
INCOME TAXES	NOTE 5. INCOME TAXES The geographic distribution of pretax income from continuing operations is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Domestic ​ $ (20,597) ​ $ 22,325 ​ $ 29,088 Foreign ​ 87,791 ​ 150,051 ​ 169,103 ​ ​ $ 67,194 ​ $ 172,376 ​ $ 198,191 ​ The provision for income taxes from continuing operations is summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Current: ​ ​ ​ Federal ​ $ (9,627) ​ $ 1,423 ​ $ 26,550 State ​ 882 ​ 12 ​ 601 Foreign ​ 18,429 ​ 13,772 ​ 9,621 Total current provision ​ $ 9,684 ​ $ 15,207 ​ $ 36,772 Deferred: ​ ​ ​ Federal ​ $ 3,822 ​ $ 4,021 ​ $ 28,297 State ​ (178) ​ 2,363 ​ (1,000) Foreign ​ (2,629) ​ 3,636 ​ (1,979) Total deferred provision ​ 1,015 ​ 10,020 ​ 25,318 Total provision for income taxes ​ $ 10,699 ​ $ 25,227 ​ $ 62,090 ​ The Company’s effective tax rates differ from the U.S. federal statutory rate of 21% for the years ended December 31, 2019 and December 31, 2018, primarily due to the benefit of tax credits and earnings in foreign jurisdictions which are subject to lower tax rates, offset by additional GILTI tax in the US and withholding taxes. The Company’s effective tax rate differs from the U.S. federal statutory rate of 35% for the year ended December 31, 2017, primarily due to the benefit related to the wind down of our solar inverter business and earnings in foreign jurisdictions, which are subject to lower tax rates, offset by the impact of U.S. tax reform. The principal causes of the difference between the federal statutory rate and the effective income tax rate for each the years below are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 ​ 2018 ​ 2017 Income taxes per federal statutory rate ​ $ 14,111 ​ $ 36,199 ​ $ 69,348 State income taxes, net of federal deduction ​ ​ 10 ​ ​ 2,372 ​ ​ 1,794 Transition tax - U.S. Tax Reform ​ ​ — ​ ​ 1,174 ​ ​ 61,690 Corporate tax rate changes - U.S. Tax Reform ​ ​ — ​ ​ (652) ​ ​ 11,177 Tax benefit associated with inverter business wind down ​ ​ — ​ ​ — ​ ​ (33,837) Stock based compensation ​ ​ (97) ​ ​ (974) ​ ​ (5,263) GILTI Tax ​ ​ 8,796 ​ ​ 13,064 ​ ​ — Tax effect of foreign operations ​ ​ (13,086) ​ ​ (19,162) ​ ​ (47,482) Uncertain tax position ​ ​ (4,487) ​ ​ (3,088) ​ ​ 4,948 Unremitted earnings ​ ​ 1,624 ​ ​ 2,564 ​ ​ — Tax credits ​ ​ (6,280) ​ ​ (9,844) ​ ​ (658) Change in valuation allowance ​ ​ 7,222 ​ ​ (1,306) ​ ​ 841 Withholding taxes ​ ​ 6,500 ​ ​ 1,371 ​ ​ — Other permanent items, net ​ ​ (3,614) ​ ​ 3,509 ​ ​ (468) Total provision for income taxes ​ $ 10,699 ​ $ 25,227 ​ $ 62,090 ​ ​ Deferred tax assets and liabilities are recognized for the future tax consequences of differences between the carrying amounts of assets and liabilities and their respective tax bases using enacted tax rates in effect for the year in which the differences are expected to be reversed. Significant deferred tax assets and liabilities consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 Deferred tax assets ​ ​ Stock based compensation ​ $ 1,757 ​ $ 1,337 Net operating loss and tax credit carryforwards ​ 86,879 ​ 38,622 Interest expense limitation ​ ​ 7,620 ​ ​ — Pension obligation ​ 13,473 ​ 3,302 Excess and obsolete inventory ​ 3,217 ​ 2,161 Deferred revenue ​ 3,305 ​ 6,903 Employee bonuses and commissions ​ 2,537 ​ 1,874 Depreciation and amortization ​ 29,015 ​ 29,525 Operating lease liabilities ​ ​ 23,451 ​ ​ — Other ​ 9,685 ​ 9,961 Deferred tax assets ​ 180,939 ​ 93,685 Less: Valuation allowance ​ (76,206) ​ (30,924) Net deferred tax assets ​ 104,733 ​ 62,761 Deferred tax liabilities ​ ​ Depreciation and amortization ​ 41,549 ​ 17,723 Unremitted earnings ​ 4,740 ​ 3,529 Operating lease right-of-use assets ​ ​ 22,774 ​ ​ — Other ​ 2,966 ​ 1,267 Deferred tax liabilities ​ 72,029 ​ 22,519 Net deferred tax assets ​ $ 32,704 ​ $ 40,242 ​ Of the $32.7 million and $40.2 million net deferred tax asset at December 31, 2019 and 2018, respectively, $42.7 million and $47.1 million is reflected as a net non-current deferred tax asset and $10.0 million and $7.0 million is reflected as a long-term liability at December 31, 2019 and 2018, respectively. As of December 31, 2019, the Company has recorded a valuation allowance on $16.0 million of its U.S. domestic deferred tax assets, largely attributable to acquired federal capital loss carryforwards for which the Company does not have sufficient income in the character to realize that attribute, and state carryforward attributes that are expected to expire before sufficient income can be realized in those jurisdictions. The remaining valuation allowance on deferred tax assets approximates $60.2 million and is associated primarily with operations in Austria, Germany, Hong Kong and Switzerland. As of December 31, 2019, there is not sufficient positive evidence to conclude that such deferred tax assets, presently reduced by a valuation allowance, will be recognized. The December 31, 2019 valuation allowance balance reflects an increase of $45.3 million during the year. The change in the valuation allowance is primarily due to increases from acquired Artesyn positions and current year activity, partially offset by decreases due to foreign exchange movements As of December 31, 2019, the Company had U.S., foreign and state tax loss carryforwards of $54.4 million, $206.8 million, and $146.2 million, respectively. Additionally, the Company had $40.7 million and $32.9 million of capital loss and interest expense limitation carryforwards, respectively. Finally, the Company had U.S. and state tax credit carryforwards of $3.8 million and $1.8 million, respectively. The U.S. and state net operating losses, tax credits, and interest expense limitation are subject to various utilization limitations under Section 382 of the Internal Revenue Code and applicable state laws. These Section 382 limited attributes have various expiration periods through 2036 or, in the case of the interest expense limitation amount, no expiration period. The majority of the foreign jurisdiction, and $4.6 million of the federal net operating loss carry forwards, have no expiration period. We operate under a tax holiday in one of our foreign jurisdictions. This tax holiday is in effect through June 30, 2027. The tax holiday is conditional upon our meeting certain employment and investment thresholds. The impact of the tax holiday decreased foreign taxes by $4.0 million and $17.8 million for 2019 and 2018, respectively. The benefit of the tax holiday on earnings per diluted share was $0.12 and $0.47 for 2019 and 2018, respectively. In the third quarter of 2019, following a review of our operations, liquidity and funding, tax implications of cash repatriation, political risk, and investment opportunities, we determined that the ability to access certain amounts of foreign earnings that were previously indefinitely reinvested would provide greater investment returns, treasury controls, and other working capital needs if repatriated to the U.S. Accordingly, in the third quarter of 2019, we withdrew the permanent reinvestment assertion on $123.9 million of earnings generated by certain of our operations through December 2018. Resulting from this change in permanent reinvestment assertion, the Company recorded a deferred tax liability of $2.9 million related to withholding and state income taxes. There is no certainty as to the timing of when such foreign earnings will be distributed to the United States in whole or in part. Certain foreign subsidiary earnings are subject to U.S. taxation under the U.S. Tax Act, which also repeals U.S. taxation on the subsequent repatriation of those earnings. We have not provided for U.S. state or foreign income taxes on $26.5 million of our subsidiaries’ undistributed earnings as of December 31, 2019. The $26.5 million of undistributed foreign earnings continue to be reinvested in our foreign operations, as we have determined that these earnings are necessary to support our planned growth and strategic acquisitions in our foreign operations, and as a result, these earnings remain indefinitely reinvested in those operations. In making this decision, we considered cash needs for investing in our existing businesses, currency controls, and the tax cost of cash repatriation. Determination of the amount of unrecognized deferred income tax liability related to these earnings is not practicable. We account for uncertain tax positions by applying a minimum recognition threshold to tax positions before recognizing these positions in the financial statements. The reconciliation of our total gross unrecognized tax benefits is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Balance at beginning of period ​ $ 13,162 ​ $ 15,990 ​ $ 11,401 Additions based on tax positions taken during a prior period ​ 484 ​ 94 ​ 1,258 Additions based on tax positions taken during a prior period - acquisitions ​ 4,479 ​ 757 ​ — Additions based on tax positions taken during the current period ​ — ​ — ​ 4,433 Reductions based on tax positions taken during a prior period ​ (4,295) ​ (153) ​ — Reductions related to a lapse of applicable statute of limitations ​ (821) ​ (3,144) ​ (1,102) Reductions related to a settlement with taxing authorities ​ — ​ (382) ​ — Balance at end of period ​ $ 13,009 ​ $ 13,162 ​ $ 15,990 ​ The unrecognized tax benefits of $13.0 million, if recognized, will impact the Company’s effective tax rate. In accordance with our accounting policy, we recognize accrued interest and penalties related to unrecognized tax benefits as a component of tax expense. We had $3.0 million and $1.2 million of accrued interest and penalties at December 31, 2019 and 2018, respectively. We expect the total amount of tax contingencies will decrease by approximately $3.5 million in 2020 based on statute of limitation expiration. With few exceptions, the Company is no longer subject to federal, state or foreign income tax examinations by tax authorities for years before 2016.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2019
Earnings Per Share
EARNINGS PER SHARE	NOTE 6. 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 diluted EPS is similar to the computation of 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 earnings per share for the years ended December 31, 2019, 2018 and 2017: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Income from continuing operations ​ $ 56,495 ​ $ 147,149 ​ $ 136,101 Income from continuing operations attributable to noncontrolling interest ​ 34 ​ 86 ​ — Income from continuing operations attributable to Advanced Energy Industries, Inc. ​ $ 56,461 ​ $ 147,063 ​ $ 136,101 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic weighted-average common shares outstanding ​ 38,281 ​ 39,081 ​ 39,754 Assumed exercise of dilutive stock options and restricted stock units ​ 214 ​ 271 ​ 422 Diluted weighted-average common shares outstanding ​ 38,495 ​ 39,352 ​ 40,176 Continuing operations: ​ ​ ​ Basic earnings per share ​ $ 1.47 ​ $ 3.76 ​ $ 3.42 Diluted earnings per share ​ $ 1.47 ​ $ 3.74 ​ $ 3.39 ​ The following stock options and restricted units were excluded in the computation of diluted earnings per share because they were anti-dilutive: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Restricted stock units — 2 — ​ Share Repurchase In September 2015, our Board of Directors authorized a program to repurchase up to $150.0 million of our common stock over a thirty-month period. In November 2017, our Board of Directors approved an extension of the share repurchase program to December 2019 from its original maturity of March 2018. In May 2018, our Board of Directors approved a $50 million increase in its authorization to repurchase shares of our common stock under this same program. On December 18, 2019, the Board of Directors authorized to remove the expiration date to the Company’s share repurchase program and increase the authorized amount by $25.1 million. As of December 31, 2019, the Company is authorized to repurchase shares of the Company’s common stock of up to a total of $50.0 million. In order to execute the repurchase of shares of our common stock, the Company periodically enters into stock repurchase agreements. During the years ended December 31, 2019, 2018 and 2017 the Company has repurchased the following shares of common stock: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ (in thousands, except per share amounts) ​ 2019 2018 2017 Amount paid to repurchase shares ​ $ — ​ $ 95,125 ​ $ 29,993 Number of shares repurchased ​ — ​ 1,696 ​ 422 Average repurchase price per share ​ $ — ​ $ 56.07 ​ $ 71.07 ​

Marketable Securities

Marketable Securities	12 Months Ended
	Dec. 31, 2019
Marketable Securities
MARKETABLE SECURITIES	NOTE 7. MARKETABLE SECURITIES As of December 31, 2019, and December 31, 2018, our marketable securities consisted of certificates of deposit and, due to their short-term nature, the fair value of these securities approximated their carrying values which were $2.6 million and $2.5 million at December 31, 2019 and 2018, respectively. The maturities of our certificates of deposit as of December 31, 2019 ranged from March 18, 2020 to October 17, 2020. 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 December 31, 2019, we do not believe any of the underlying issuers of our marketable securities are at risk of default.

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2019
Derivative Financial Instruments
DERIVATIVE FINANCIAL INSTRUMENTS	We are impacted by changes in foreign currency exchange rates. We may manage these risks through the use of derivative financial instruments, primarily forward contracts with banks. During the years ended December 31, 2018 and 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 economically 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 forward contracts outstanding as of December 31, 2019 and 2018. At December 31, 2017, we had outstanding Euro and Pound Sterling forward contracts. The notional amount of foreign currency exchange forward 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 years ended December 31, 2019, 2018, and 2017, the gains and losses recorded related to the foreign currency exchange rate forward contracts are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Foreign currency loss from foreign currency exchange rate forward contracts ​ $ — ​ $ (750) ​ $ (1,438) ​ These gains and losses were offset by corresponding foreign currency gains and losses on the related intercompany debt and both are included as a component of Other income (expense), net, in our 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. 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 Consolidated Statement of Operations.

Accounts and Other Receivable

Accounts and Other Receivable	12 Months Ended
	Dec. 31, 2019
Accounts and Other Receivable
ACCOUNTS AND OTHER RECEIVABLE	NOTE 9. 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: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ 2019 2018 Amounts billed, net ​ $ 227,528 ​ $ 80,709 Unbilled receivables ​ ​ 19,036 ​ 19,733 Total receivables, net ​ $ 246,564 ​ $ 100,442 ​ Amounts billed, net consist of amounts that have been invoiced to our customers in accordance with terms and conditions, and are shown net of an allowance for doubtful accounts. These receivables are all short term in nature and do not include any financing components. Unbilled receivables consist of amounts where we have satisfied our contractual obligations related to inventory stocking contracts with customers. Such amounts are typically invoiced 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. These contracts do not include any financing components.

Inventories

Inventories	12 Months Ended
	Dec. 31, 2019
Inventories
INVENTORIES	NOTE 10. 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 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2019 2018 Parts and raw materials ​ $ 134,816 ​ $ 76,647 Work in process ​ 10,269 ​ 6,644 Finished goods ​ 84,934 ​ 14,696 Total ​ $ 230,019 ​ $ 97,987 ​

Property and Equipment, Net

Property and Equipment, Net	12 Months Ended
	Dec. 31, 2019
Property and Equipment, Net
PROPERTY AND EQUIPMENT, NET	NOTE 11. PROPERTY AND EQUIPMENT, NET Property and equipment, net is comprised of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2019 2018 Buildings and land ​ $ 1,693 ​ $ 1,737 Machinery and equipment ​ 108,945 ​ 41,330 Computer and communication equipment ​ 29,106 ​ 24,051 Furniture and fixtures ​ 4,119 ​ 3,203 Vehicles ​ 262 ​ 282 Leasehold improvements ​ 33,041 ​ 20,593 Construction in process ​ 9,089 ​ 867 ​ ​ 186,255 ​ 92,063 Less: Accumulated depreciation ​ (78,146) ​ (60,794) Property and equipment, net ​ $ 108,109 ​ $ 31,269 ​ Depreciation expense is recorded in continuing operations and allocated within Cost of Sales, Research and development expense and Selling, general and administrative expense in our Consolidated Statements of Operations as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Depreciation expense ​ $ 13,979 ​ $ 7,818 ​ $ 5,074 ​

Goodwill

Goodwill	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets
GOODWILL	NOTE 12. GOODWILL The following summarizes the changes in goodwill during the years ended December 31, 2019 and 2018: ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2017 ​ $ 53,812 Measurement period adjustments to preliminary purchase price allocation ​ ​ — Additions from acquisition ​ ​ 49,252 Foreign currency translation ​ ​ (1,164) December 31, 2018 ​ ​ 101,900 Measurement period adjustments to preliminary purchase price allocation ​ ​ (41,996) Additions from acquisition ​ ​ 143,262 Foreign currency translation ​ ​ (234) December 31, 2019 ​ $ 202,932 ​ Adjustments are the result of finalizing the LumaSense acquisition purchase price allocation along with measurement period adjustments to the purchase price allocation from the Artesyn acquisition with the residual adjustments getting recorded to goodwill. Additions are the result of our acquisition of Artesyn during the year ended December 31, 2019 and our acquisitions of LumaSense, Trek and Monroe’s electrostatic technology and product line during the year ended December 31, 2018, as described in Note 2. Business Acquisitions.

Intangible Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets
INTANGIBLE ASSETS	NOTE 13. INTANGIBLE ASSETS Intangible assets consisted of the following as of December 31, 2019 and 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Carrying Accumulated Net Carrying December 31, 2019 ​ Amount ​ Amortization ​ Amount Technology ​ $ 83,368 ​ $ (14,250) ​ $ 69,118 Customer relationships ​ 108,995 ​ (18,197) ​ 90,798 Trademarks and other ​ 26,888 ​ (2,793) ​ 24,095 Total ​ $ 219,251 ​ $ (35,240) ​ $ 184,011 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Carrying Accumulated Net Carrying December 31, 2018 ​ Amount ​ Amortization ​ Amount Technology ​ $ 39,879 ​ $ (7,927) ​ $ 31,952 Customer relationships ​ 35,509 ​ (13,484) ​ 22,025 Trademarks and other ​ 2,501 ​ (1,568) ​ 933 Total ​ $ 77,889 ​ $ (22,979) ​ $ 54,910 ​ At December 31, 2019, the weighted average remaining useful life of intangibles subject to amortization was approximately 11.2 years. Amortization expense related to intangible assets is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Amortization expense ​ $ 12,168 ​ $ 5,774 ​ $ 4,350 ​ Estimated amortization expense related to intangibles is as follows: ​ ​ ​ ​ Year Ending December 31, ​ ​ 2020 ​ $ 20,109 2021 ​ 20,009 2022 ​ 19,745 2023 ​ 19,727 2024 ​ 16,888 Thereafter ​ 87,533 Total ​ $ 184,011 ​

Restructuring Costs

Restructuring Costs	12 Months Ended
	Dec. 31, 2019
Restructuring Costs
RESTRUCTURING COSTS	NOTE 14. RESTRUCTURING COSTS During the year ended December 31, 2019, we recorded a total pre-tax charge of $5.0 million for severance and facility relocation associated with our manufacturing footprint consolidation and optimization, acquisition integration, and reorganization for business efficiency improvement. For the year ended December 31, 2018, we recorded total severance and related costs of $4.2 million. The cumulative costs recognized under this restructuring plan are $9.3 million. ​ The table below summarizes the restructuring charges for the years ended: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cumulative Cost ​ ​ ​ ​ ​ ​ ​ ​ Through December 31, ​ ​ 2019 ​ ​ 2018 ​ ​ 2019 Severance and related charges $ 3,041 ​ $ 4,239 ​ $ 7,280 Facility relocation and closure charges 1,996 ​ — ​ 1,996 Total restructuring charges $ 5,038 ​ $ 4,239 ​ $ 9,277 ​ The following table summarizes our restructuring liabilities at December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cost ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Incurred ​ Cost Paid ​ Effect of ​ ​ ​ ​ ​ Balance at ​ and ​ or ​ Changes in ​ Balance at ​ ​ December 31, ​ Charged to ​ Otherwise ​ Exchange ​ December 31, ​ ​ 2018 ​ Expense ​ Settled ​ Rates ​ 2019 Total restructuring liabilities ​ $ 3,806 ​ $ 5,038 ​ $ (6,673) ​ $ 1 ​ $ 2,172 ​

Warranties

Warranties	12 Months Ended
	Dec. 31, 2019
Warranties
WARRANTIES	NOTE 15. 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: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Balances at beginning of period ​ $ 2,084 ​ $ 2,312 ​ $ 2,329 Warranty acquired in business combinations ​ 4,818 ​ 305 ​ 118 Increases to accruals ​ 1,752 ​ 1,606 ​ 2,029 Warranty expenditures ​ (2,249) ​ (2,127) ​ (2,184) Effect of changes in exchange rates ​ 8 ​ (12) ​ 20 Balances at end of period ​ $ 6,413 ​ $ 2,084 ​ $ 2,312 ​

Leases

Leases	12 Months Ended
	Dec. 31, 2019
Leases
LEASES	NOTE 16. LEASES The Company adopted authoritative guidance related to leases effective January 1, 2019 using the modified retrospective method. The comparative information presented in the Consolidated Financial Statements was not restated and is reported under the accounting standards in effect for the periods presented. See the section Leases in Note 1. Operations and Summary of Significant Accounting Policies and Estimates The Company’s leases consist primarily of manufacturing and office space under non-cancelable operating leases expiring at various dates through 2033. Leases with an original term of twelve months or less are not reported in the Consolidated Balance Sheet; expense for these short-term leases is recognized on a straight-line basis over the lease term. Most leases include one or more options to renew. The exercise of these renewal options is at the Company’s discretion. We regularly evaluate the renewal options and when they are reasonably certain of exercise, we include the renewal period in the lease term, the right-of-use assets and lease liabilities. Due to the Company’s centralized treasury function, the Company utilizes a portfolio approach to discount its lease obligations. The Company assesses the expected lease term at lease inception and discounts the lease using a fully secured annual incremental borrowing rate, adjusted for time value corresponding with the expected lease term. New leases are negotiated and executed to meet business objectives on an on-going basis. During the first fiscal quarter of 2020, we expect to record additional right of use assets and related liabilities for facilities in Fort Collins, Colorado, USA. The lease extensions in Fort Collins, Colorado commenced in January 2020 and extended the expected lease terms to 16 years; the right of use asset and operating lease liability Components of operating lease cost were as follows: ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, 2019 Operating lease cost $ 11,052 ​ Short-term and variable lease cost ​ 4,726 ​ Total operating lease cost $ 15,778 ​ ​ Maturities of our lease liabilities for all operating leases at December 31, 2019 are as follows: ​ ​ ​ ​ ​ Year Ending December 31, ​ 2020 ​ $ 22,351 2021 ​ 19,771 2022 ​ 13,503 2023 ​ 10,786 2024 ​ ​ 9,601 Thereafter ​ ​ 56,355 Total lease payments ​ ​ 132,367 Less: Interest ​ ​ (23,517) Present value of lease liabilities ​ $ 108,850 ​ ​ Other information related to leases, including supplemental cash flow information, consists of: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ December 31, 2019 Weighted average remaining lease term (in years) ​ ​ ​ 7.50 ​ Weighted average discount rate ​ ​ ​ 4.05 % Cash paid for operating leases ​ ​ $ 12,101 ​ Right-of-use assets obtained in exchange for operating lease liabilities (1) ​ ​ $ 84,551 ​ ​ (1) Included in 2019 are the right-of-use assets of $60.1 million obtained in connection with the acquisition of Artesyn in September 2019. See Note 2. Business Combinations for more details. Comparative Information as Reported Under Previous Accounting Standards The following comparative information is reported based upon previous accounting standards in effect for the periods presented. Future minimum lease payments under operating leases were: ​ ​ ​ ​ Year Ending December 31, ​ 2019 ​ $ 9,093 2020 ​ 7,561 2021 ​ 6,938 2022 ​ 3,862 2023 ​ ​ 3,448 Thereafter ​ 18,349 Total lease payments ​ $ 49,251 ​ Rent expense for operating leases was approximately $7.4 million and $6.5 million during the years ended December 31, 2018 and 2017, respectively.

Employee Retirement Plans and P

Employee Retirement Plans and Postretirement Benefits	12 Months Ended
	Dec. 31, 2019
Employee Retirement Plans and Postretirement Benefits
EMPLOYEE RETIREMENT PLANS AND POSTRETIREMENT BENEFITS	NOTE 17. EMPLOYEE RETIREMENT PLANS AND POSTRETIREMENT BENEFITS Defined Contribution Plans We have a 401(k) profit-sharing and retirement savings plan covering substantially all full-time U.S. employees. Participants may defer up to the maximum amount allowed as determined by law. Participants are immediately vested in their contributions. Profit-sharing contributions to the plan, which are discretionary, are approved by the Board of Directors. Vesting in the profit-sharing contribution account is based on years of service, with most participants fully vested after four years of credited service. For the years ended December 31, 2019, 2018, and 2017 our contribution for participants in our 401(k) plan was based on matching 50% of contributions made by employees up to 6% of the employee’s compensation. During the years ended December 31, 2019, 2018, and 2017 we recognized total defined contribution plan costs of $1.6 million, $1.4 million, and $1.1 million, respectively. Defined Benefit Plan We maintain defined benefit pension plans for certain of our non-U.S. employees in the U.K., Germany, and Philippines. Each plan is managed locally and in accordance with respective local laws and regulations. ​ 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. ​ In connection with the acquisition of Artesyn in September of 2019, the Company acquired certain pension plans and, as a result, started including the related balances in its Consolidated Balance Sheets at December 31, 2019 and the expenses attributable to these plans for the period from September 10, 2019 to December 31, 2019 in its Consolidated Statement of Operations. See Note 2. Business Acquisitions ​ The information provided below includes one pension plan which is part of discontinued operations. As such, all related liabilities and expenses are reported in discontinued operations in the Company’s Consolidated Balance Sheets and Consolidated Statements of Operations for all periods presented. ​ The Company’s projected benefit obligation and plan assets for defined benefit pension plans at December 31, 2019 and 2018 and the related assumptions used to determine the related liabilities are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 Projected benefit obligation, beginning of year ​ $ 33,178 ​ $ 34,498 Acquisition ​ 48,350 ​ 1,063 Service cost ​ 272 ​ 841 Interest cost ​ 1,211 ​ 802 Actuarial loss ​ (193) ​ (988) Benefits paid ​ (1,779) ​ (1,113) Translation adjustment ​ 2,223 ​ (1,925) Projected benefit obligation, end of year ​ $ 83,262 ​ $ 33,178 Fair value of plan assets, beginning of year ​ $ 13,433 ​ $ 14,181 Acquisitions ​ 102 ​ 981 Actual return on plan assets ​ 380 ​ 675 Contributions ​ 644 ​ 828 Benefits paid ​ (1,176) ​ (1,086) Actuarial gain ​ 1,064 ​ (1,357) Translation adjustment ​ 456 ​ (789) Fair value of plan assets, end of year ​ $ 14,903 ​ $ 13,433 Funded status of plan ​ $ (68,359) ​ $ (19,745) ​ The components of net periodic pension benefit cost recognized in our Consolidated Statements of Operations for the periods presented are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Service cost ​ $ 272 ​ $ 841 ​ $ — Interest cost ​ ​ 1,211 ​ ​ 802 ​ ​ 809 Expected return on plan assets ​ (615) ​ (665) ​ (597) Amortization of actuarial gains and losses ​ 411 ​ 478 ​ 503 Net periodic pension cost ​ $ 1,279 ​ $ 1,456 ​ $ 715 ​ Assumptions used in the determination of the net periodic pension cost are: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Discount rate 2.7 % 2.8 % 2.6 % Expected long-term return on plan assets 4.6 % 4.8 % 4.8 % ​ The fair value of the Company’s qualified pension plan assets by category for the years ended December 31, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ Level 1 Level 2 Level 3 Total Multi-Asset Fund ​ $ — ​ $ 4,825 ​ $ — ​ $ 4,825 Diversified Growth Fund ​ — ​ 4,855 ​ — ​ 4,855 Index-Linked Gilts ​ — ​ 1,934 ​ — ​ 1,934 Corporate Bonds ​ — ​ 2,090 ​ — ​ 2,090 Insurance Contracts ​ ​ — ​ — ​ 1,045 ​ 1,045 Cash ​ 154 ​ — ​ — ​ 154 Total ​ $ 154 ​ $ 13,704 ​ $ 1,045 ​ $ 14,903 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2018 ​ Level 1 Level 2 Level 3 Total Multi-Asset Fund ​ $ — ​ $ 4,570 ​ $ — ​ $ 4,570 Diversified Growth Fund ​ — ​ 4,650 ​ — ​ 4,650 Index-Linked Gilts ​ — ​ 2,044 ​ — ​ 2,044 Corporate Bonds ​ — ​ 2,044 ​ — ​ 2,044 Insurance Contracts ​ ​ — ​ ​ — ​ ​ 72 ​ ​ 72 Cash ​ 53 ​ — ​ — ​ 53 Total ​ $ 53 ​ $ 13,308 ​ $ 72 ​ $ 13,433 ​ At December 31, 2019 our plan’s assets of $14.9 million were invested in five separate funds including a multi-asset fund (32.4%), a diversified growth fund (32.6%), an index-linked gilt (13.0%), corporate bonds (14.0%), and insurance contracts (7%). The asset and growth funds aim to generate an ‘equity-like’ return over an economic cycle with significantly reduced volatility relative to equity markets and have scope to use a diverse range of asset classes, including equities, bonds, cash and alternatives, e.g. property, infrastructure, high yield bonds, floating rate debt, private, equity, hedge funds and currency. The bond fund and gilt fund are invested in index-linked gilts and corporate bonds. These investments are intended to provide a degree of protection against changes in the value of our plan’s liabilities related to changes in long-term expectations for interest rates and inflation expectations. Expected future payments under defined benefit pension plans, based on foreign exchange rates as of December 31, 2019, are as follows: ​ ​ ​ ​ Expected Future Benefit Payments ​ ​ ​ 2020 $ 6,113 2021 ​ ​ 7,039 2022 ​ ​ 5,673 2023 ​ ​ 5,716 2024 ​ ​ 14,487 Thereafter ​ ​ 134,802 ​

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2019
Stock-Based Compensation
STOCK-BASED COMPENSATION	NOTE 18. As of December 31, 2019, we had two active stock-based incentive compensation plan: the 2017 Omnibus Incentive Plan and the Employee Stock Purchase Plan (“ESPP”). All new equity compensation grants are issued under these two plans; however, outstanding awards previously issued under inactive plans will continue to vest and remain exercisable in accordance with the terms of the respective plans. Our stock plans are administered by the Board of Directors Compensation Committee. At December 31, 2019, there were 3.3 million shares reserved and 2.5 million shares available for future grant under our stock-based incentive plans. On May 4, 2017, the stockholders approved the Company’s 2017 Omnibus Incentive Plan ("the 2017 Plan") and reserved 5.2 million shares under the plan. The 2017 Plan replaced the 2008 Omnibus Incentive Plan ("the 2008 Plan"), and all awards previously granted under the 2008 Plan continue to vest and/or are exercisable under the 2017 Plan in accordance with their original terms and conditions. The 2017 Plan and 2008 Plan provide for the grant of stock options, stock appreciation rights, restricted stock, stock units (including deferred stock units), unrestricted stock, and dividend equivalent rights. Additionally, awards issued may be issued as performance-based awards to align stock compensation awards to the attainment of annual or long-term performance goals. As of December 31, 2019, there were 2.3 million shares available for grant under the 2017 Plan. The Company grants restricted stock units and performance stock units. The grant date fair values of restricted stock units and performance stock units are based on the closing market price of our common stock on the grant date. Our restricted stock units vest based on continued service. Our performance stock units vest based on achievement of certain performance goals and certification of performance achievement by the Compensation Committee of the Board of Directors. Stock-based compensation expense, net of forfeitures, is recognized on a straight-line basis over the requisite service period. For performance stock units, compensation expense is updated for the Company’s expected performance level against performance goals at the end of each reporting period, which involves judgment as to achievement of certain performance metrics. ​ Stock-based Compensation Expense 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 years ended December 31 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Stock-based compensation expense ​ $ 7,327 ​ $ 9,703 ​ $ 12,549 ​ Our stock-based compensation expense is based on the value of the portion of share-based payment awards that are ultimately expected to vest, assuming estimated forfeitures at the time of grant. Estimated forfeiture rates for our stock-based compensation expense applicable to stock options and restricted stock units ("RSU’s") was approximately 10%, 10% and 17% for the years ended December 31, 2019, 2018 and 2017, respectively. Restricted Stock Units The fair value of our Restricted Stock Units ("RSUs") is determined based upon the closing fair market value of our common stock on the grant date. Changes in the unvested RSU’s during the years ended December 31, 2019, 2018 and 2017 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2019 ​ 2018 ​ 2017 ​ ​ ​ Weighted- ​ Weighted- ​ Weighted- ​ ​ ​ ​ Average ​ ​ ​ Average ​ ​ ​ Average ​ ​ ​ ​ Grant ​ ​ ​ Grant ​ ​ ​ Grant ​ ​ Shares ​ Value ​ Shares ​ Value ​ Shares ​ Value RSUs outstanding at beginning of period 352 ​ $ 58.17 386 ​ $ 51.06 354 ​ $ 29.60 RSUs granted 380 ​ 52.24 245 ​ 64.48 252 ​ 63.63 RSUs vested (155) ​ 50.95 (207) ​ 54.94 (211) ​ 30.62 RSUs forfeited (43) ​ 51.82 (72) ​ 50.79 (9) ​ 33.91 RSUs outstanding at end of period 534 ​ $ 56.56 352 ​ $ 58.17 386 ​ $ 51.06 ​ The total intrinsic value of RSUs converted to shares for the years ended December 31, 2019, 2018 and 2017 were $8.3 million, $13.6 million and $14.8 million, respectively. As of December 31, 2019, there was $5.9 million of total unrecognized compensation cost, net of expected forfeitures related to non-vested RSUs granted, which is expected to be recognized through fiscal November 2022, with a weighted-average remaining vesting period of 1.3 years. Stock Options 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 The fair value of options granted during the year ended December 31, 2015 was estimated on the date of grant using the Black-Scholes-Merton option pricing model using the following assumptions: the risk-free interest rate was 1.1% - 1.4%, the expected term was 4.3 years and expected volatility was 43%. The risk-free interest rate was based on the five-year U.S. Treasury Bill at the time of the grant. We utilize our historical experience in determining the expected term of our stock options and volatility of our common stock. We have not historically issued dividends. Changes in our outstanding stock options during the years ended December 31, 2019, 2018 and 2017 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2019 ​ 2018 ​ 2017 ​ ​ ​ Weighted- ​ Weighted- ​ Weighted- ​ ​ ​ ​ Average ​ ​ ​ Average ​ ​ ​ Average ​ ​ ​ ​ Exercise ​ ​ ​ Exercise ​ ​ ​ Exercise ​ ​ Shares ​ Price ​ Shares ​ Price ​ Shares ​ Price Options outstanding at beginning of period 230 ​ $ 20.73 317 ​ $ 18.97 474 ​ $ 17.47 Options exercised (42) ​ 17.73 (83) ​ 14.41 (152) ​ 14.32 Options forfeited — ​ — — ​ — (2) ​ 26.32 Options expired (3) ​ 9.91 (4) ​ 11.97 (3) ​ 11.09 Options outstanding at end of period 185 ​ $ 21.56 230 ​ $ 20.73 317 ​ $ 18.97 Options vested during the year — ​ 2 ​ 9 ​ ​ ​ The total intrinsic value of options exercised for the years ended December 31, 2019, 2018 and 2017 was $1.6 million, $4.1 million and $9.7 million, respectively. All options outstanding at December 31, 2019 are vested and have aggregate intrinsic value of $9.2 million and weighted-average remaining contractual life of 4.1 years. The following table summarizes information about the stock options outstanding at December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding ​ Options Exercisable ​ ​ ​ ​ Weighted-Average ​ Weighted- ​ ​ ​ Weighted- ​ ​ Number ​ Remaining ​ Average ​ Number ​ Average Range of Exercise Prices Outstanding Contractual Life Exercise Price Exercisable Exercise Price 9.51 - 13.85 23 1.42 years ​ $ 12.00 23 ​ $ 12.00 14.21 - 16.25 20 0.72 years ​ 15.06 20 ​ 15.06 18.77 - 18.77 43 4.75 years ​ 18.77 43 ​ 18.77 26.32 - 26.32 99 5.10 years ​ 26.32 99 ​ 26.32 9.51 - 26.32 185 4.09 years ​ $ 21.56 185 ​ $ 21.56 ​ ​ Employee Stock Purchase Plan The ESPP, a stockholder-approved plan, provides for the issuance of rights to purchase up to 1,000,000 shares of common stock. In May 2010, stockholders approved an increase from 500,000 to 1,000,000 shares authorized for sale under our ESPP. Employees below the Vice President level are eligible to participate in the ESPP if employed by us for at least 20 hours per week during at least five months per calendar year. Participating employees may contribute up to the lesser of 15% of their eligible earnings or $5,000 during each plan period. Currently, the plan period is six months. The purchase price of common stock purchased under the ESPP is currently equal to the lower of: 1) 85% of the fair market value of our common stock on the commencement date of each plan period or 2) 85% of the fair market value of our common shares on each plan period purchase date. At December 31, 2019, 0.2 million shares remained available for future issuance under the ESPP. Purchase rights granted under the ESPP are valued using the Black-Scholes-Merton model. As of December 31, 2019, there was $0.2 million of total unrecognized compensation cost related to the ESPP that is expected to be recognized over a remaining period of five months. Total compensation expense was $0.5 million for the year ended December 31, 2019 and $0.4 million for the year ended December 31, 2018, and $0.2 million for the year ended December 31, 2017. The fair value of each purchase right granted under the ESPP was estimated on the date of grant using the Black-Scholes-Merton option pricing model with the following assumptions: ​ ​ ​ ​ ​ ​ ​ ​ ​ 2019 2018 2017 Risk-free interest rates 1.62% - 2.31 % 2.10% - 2.56 % 1.07% - 1.45 % Expected dividend yield rates — % — % — % Expected term 0.5 years 0.5 years 0.5 years ​ Expected volatility 41.3 % 38.0 % 33.3 % ​ The risk-free interest rate is based on the six-month U.S. Treasury Bill at the time of the grant. We utilize our historical experience in determining the expected term of our stock options and volatility of our common stock. We have not historically issued dividends.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies
COMMITMENTS AND CONTINGENCIES	NOTE 19. COMMITMENTS AND CONTINGENCIES Disputes and Legal Actions We are involved in disputes and legal actions arising in the normal course of our business. While we currently believe that the amount of any ultimate loss would not be material to our financial position, the outcome of these actions is inherently difficult to predict. In the event of an adverse outcome, the ultimate loss could have a material adverse effect on our financial position or reported results of operations. An unfavorable decision in patent litigation also could require material changes in production processes and products or result in our inability to ship products or components found to have violated third-party patent rights. We accrue loss contingencies in connection with our commitments and contingencies, including litigation, when it is probable that a loss has occurred, and the amount of the loss can be reasonably estimated. The Company is currently not a party to any legal action that the Company believes would reasonably have a material adverse impact on its business, financial condition, results of operations or cash flows. ​

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2019
Related Party Transactions
RELATED PARTY TRANSACTIONS	NOTE 20. 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 years ended December 31, 2019, 2018, and 2017, we engaged in the following transactions with companies related to members of our Board of Directors, as described below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Sales to related parties ​ $ 1,340 ​ $ 1,028 ​ $ 1,425 Number of related party customers ​ 1 ​ 1 ​ 1 ​ Our accounts receivable balance from related party customers with outstanding balances as of December 31, 2019 and December 31, 2018 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ 2019 2018 Accounts receivable from related parties ​ $ — ​ $ 109 Number of related party customers ​ 1 ​ 1 ​ We did not have any outstanding accounts payable with our related parties as of December 31, 2019 or December 31, 2018.

Geographic and Significant Cust

Geographic and Significant Customer Information	12 Months Ended
	Dec. 31, 2019
Geographic and Significant Customer Information
GEOGRAPHIC AND SIGNIFICANT CUSTOMER INFORMATION	NOTE 21. GEOGRAPHIC AND 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 years ended December 31, 2019 and 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 Applied Materials, Inc. ​ $ 164,724 20.9 % $ 258,027 35.9 % LAM Research ​ 88,251 11.2 % 109,005 15.2 % ​ 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 December 31, 2019 and December 31, 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 ​ 2018 Applied Materials, Inc. ​ $ 36,849 14.9 % $ 34,301 34.2 % Nidec Motor Corporation ​ ​ 38,071 ​ 15.4 ​ ​ * * % LAM Research ​ * * % 12,181 12.1 % ​ * Customer’s balance was less than 10% of the total accounts receivable balance. ​ Our sales to Applied Materials, Inc., LAM Research, and Nidec Corporation 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. The following table summarizes long-lived assets by geographic area as of December 31, 2019 and December 31, 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2019 2018 United States ​ $ 239,511 ​ $ 115,869 Asia ​ 301,020 ​ 12,274 Europe ​ 59,925 ​ 59,936 Total ​ $ 600,456 ​ $ 188,079 ​ Long-lived assets include property and equipment, operating lease right-of-use assets goodwill and other intangible assets.

Credit Facility

Credit Facility	12 Months Ended
	Dec. 31, 2019
Credit Facility
CREDIT FACILITY	NOTE 22. CREDIT FACILITY In September 2019, in connection with the Artesyn Acquisition Agreement, the Company entered into a credit agreement (“Credit Agreement”) that provided aggregate financing of $500.0 million, consisting of a $350.0 million senior unsecured term loan facility (the “Term Loan Facility”) and a $150.0 million senior unsecured revolving facility the (“Revolving Facility”). Both the Term Loan Facility and Revolving Facility mature on September 10, 2024. The Revolving Facility and Term Loan Facility bear interest, at the option of the Company, at a rate based on a reserve adjusted Eurodollar Rate or a Base Rate, as defined in the Credit Agreement, plus an applicable margin. Additionally, the Revolving Facility is subject to an unused line fee. As of December 31, 2019, the effective interest rate for the Revolving Facility and Term Loan Facility was 2.55% and the effective rate for the unused line fee was 0.10%. As of December 31, 2019, the Company had $150.0 million available to withdraw on the Revolving Facility and was in compliance with all covenants. The fair value of the Company’s outstanding debt approximates its carrying value of $339.0 million as of December 31, 2019. In connection ​ As of December 31, 2019, the debt obligation on our Consolidated Balance Sheets consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ Debt: ​ Amount Term Loan Facility ​ $ 341,250 Less: debt issuance costs ​ ​ (2,223) Total debt ​ ​ 339,027 Less current portion of debt ​ ​ (17,500) Total long-term debt ​ $ 321,527 ​ Contractual maturities of the Company’s debt obligations, excluding amortization of debt issuance costs, as of are as December 31, 2019 follows: ​ ​ ​ ​ ​ ​ Amount 2020 ​ $ 17,500 2021 ​ ​ 17,500 2022 ​ ​ 17,500 2023 ​ ​ 17,500 2024 ​ ​ 271,250 Total ​ $ 341,250 ​ Interest expense and unused line of credit fees were recorded in Other income (expense), net, in our Consolidated Statements of Operations as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Interest expense ​ $ 2,994 ​ $ — ​ $ — Amortization of debt issuance costs ​ ​ 186 ​ ​ — ​ ​ — Unused line of credit fees and other ​ ​ 236 ​ ​ 228 ​ ​ 66 Total interest expense ​ $ 3,416 ​ $ 228 ​ $ 66 ​

Supplemental Quarterly Financia

Supplemental Quarterly Financial Data	12 Months Ended
	Dec. 31, 2019
Supplemental Quarterly Financial Data
SUPPLEMENTAL QUARTERLY FINANCIAL DATA	NOTE 23. SUPPLEMENTAL QUARTERLY FINANCIAL DATA (UNAUDITED) The following tables present unaudited quarterly results for each of the eight quarters in the periods ended December 31, 2019 and 2018, in thousands. We believe that all necessary adjustments have been included in the amounts stated below to present fairly such quarterly information. Due to the volatility of the industries in which our customers operate, the operating results for any quarter are not necessarily indicative of results for any subsequent period. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quarter Ended ​ December 31, September 30, June 30, March 31, ​ ​ 2019 ​ 2019 ​ 2019 ​ 2019 Sales, net ​ $ 338,268 ​ $ 175,127 ​ $ 134,810 ​ $ 140,743 Gross Profit ​ $ 112,295 ​ $ 73,491 ​ $ 64,126 ​ $ 65,740 Restructuring Expense ​ $ 1,418 ​ $ 152 ​ $ 1,795 ​ $ 1,673 Operating income ​ $ 22,202 ​ $ 9,390 ​ $ 11,005 ​ $ 11,791 Income from continuing operations, net of income taxes ​ $ 10,479 ​ $ 7,256 ​ $ 23,373 ​ $ 15,387 Loss (income) from discontinued operations, net of income taxes ​ $ (210) ​ $ 375 ​ $ 8,324 ​ $ (9) Net Income ​ $ 10,269 ​ $ 7,631 ​ $ 31,697 ​ $ 15,378 Income from continuing operations attributable to noncontrolling interest ​ $ 5 ​ $ 10 ​ $ 11 ​ $ 8 Net income attributable to Advanced Energy Industries, Inc. ​ $ 10,264 ​ $ 7,621 ​ $ 31,686 ​ $ 15,370 Earnings (Loss) Per Share: ​ ​ ​ ​ Continuing Operations: ​ ​ ​ ​ Basic earnings per share ​ $ 0.27 ​ $ 0.19 ​ $ 0.61 ​ $ 0.40 Diluted earnings per share ​ $ 0.27 ​ $ 0.19 ​ $ 0.61 ​ $ 0.40 Discontinued Operations: ​ ​ ​ ​ Basic loss per share ​ $ (0.01) ​ $ 0.01 ​ $ 0.22 ​ $ — Diluted loss per share ​ $ (0.01) ​ $ 0.01 ​ $ 0.22 ​ $ — Net Income: ​ ​ ​ ​ Basic earnings per share ​ $ 0.27 ​ $ 0.20 ​ $ 0.83 ​ $ 0.40 Diluted earnings per share ​ $ 0.27 ​ $ 0.20 ​ $ 0.82 ​ $ 0.40 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quarter Ended ​ December 31, September 30, June 30, March 31, ​ ​ 2018 ​ 2018 ​ 2018 ​ 2018 Sales, net ​ $ 154,161 ​ $ 173,082 ​ $ 196,032 ​ $ 195,617 Gross Profit ​ $ 75,188 ​ $ 85,539 ​ $ 101,235 ​ $ 103,645 Restructuring Expense ​ $ 3,836 ​ $ 403 ​ $ — ​ $ — Operating income ​ $ 19,570 ​ $ 39,862 ​ $ 56,018 ​ $ 56,103 Income from continuing operations, net of income taxes ​ $ 19,222 ​ $ 35,157 ​ $ 46,400 ​ $ 46,370 Income (loss) from discontinued operations, net of income taxes ​ $ 188 ​ $ (371) ​ $ 5 ​ $ 140 Net Income ​ $ 19,410 ​ $ 34,786 ​ $ 46,405 ​ $ 46,510 Income from continuing operations attributable to noncontrolling interest ​ $ 4 ​ $ 7 ​ $ 44 ​ $ 31 Net income attributable to Advanced Energy Industries, Inc. ​ $ 19,406 ​ $ 34,779 ​ $ 46,361 ​ $ 46,479 Earnings (Loss) Per Share: ​ $ ​ ​ ​ Continuing Operations: ​ ​ ​ ​ Basic earnings per share ​ $ 0.50 ​ $ 0.90 ​ $ 1.18 ​ $ 1.17 Diluted earnings per share ​ $ 0.50 ​ $ 0.90 ​ $ 1.17 ​ $ 1.16 Discontinued Operations: ​ ​ ​ ​ Basic loss per share ​ $ — ​ $ (0.01) ​ $ — ​ $ — Diluted loss per share ​ $ — ​ $ (0.01) ​ $ — ​ $ — Net Income: ​ ​ ​ ​ ​ Basic earnings per share ​ $ 0.51 ​ $ 0.89 ​ $ 1.18 ​ $ 1.17 Diluted earnings per share ​ $ 0.50 ​ $ 0.89 ​ $ 1.17 ​ $ 1.16 ​

Operations and Summary of Sig_2

Operations and Summary of Significant Accounting Policies and Estimates (Policies)	12 Months Ended
	Dec. 31, 2019
Operations and Summary of Significant Accounting Policies and Estimates
Principles of Consolidation	Principles of Consolidation
Use of Estimates in the Preparation of the Consolidated Financial Statements	Use of Estimates in the Preparation of the Consolidated Financial Statements —
Foreign Currency Translation	Foreign Currency Translation — The functional currency of certain of our foreign subsidiaries is the local currency. Assets and liabilities of these foreign subsidiaries are translated to the United States dollar at prevailing exchange rates at the balance sheet date; revenues and expenses are translated at the average exchange rates in effect for each period. Translation adjustments resulting from this process are reported as a separate component of Other Comprehensive Income. For certain other subsidiaries the functional currency is the US Dollar. Foreign currency transactions are recorded based on exchange rates at the time such transactions arise. Subsequent changes in exchange rates for foreign currency denominated monetary assets and liabilities result in foreign currency transaction gains and losses which are reflected as unrealized (based on period end remeasurement) or realized (upon settlement of the transactions) in other income, net in our Consolidated Statements of Operations.
Fair Value of Financial Instruments	Fair Value — U.S. GAAP for fair value establishes a hierarchy that prioritizes fair value measurements based on the types of inputs used for the various valuation techniques (market approach, income approach, and cost approach). The Company’s financial assets and liabilities are measured using inputs from the three levels of the fair value hierarchy. The three levels of the hierarchy and the related inputs are as follows: ● Level 1 — Quoted prices (unadjusted) in active markets for identical assets or liabilities that the entity can access at the measurement date. ● Level 2 — Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. ● Level 3 — Unobservable inputs for the asset or liability. The Company categorizes fair value measurements within the fair value hierarchy based upon the lowest level of the most significant inputs used to determine fair value. The carrying amounts of our cash and cash equivalents, accounts receivable, accounts payable and other current assets and liabilities approximate fair value as recorded due to the short-term nature of these instruments. The fair value of derivatives is estimated utilizing observable foreign exchange rates adjusted for non-performance credit risk associated with our counterparties. The fair value of contingent consideration and other acquired assets and liabilities associated with the acquisition of Artesyn, are based on Level 3 inputs. There were transfers Note 8 Derivative Financial Instruments Note 22, Credit Facility The Company’s non-financial assets, which primarily consist of property and equipment, goodwill, and other intangible assets, are not required to be carried at fair value on a recurring basis and are reported at carrying value. However, on a periodic basis or whenever events or changes in circumstances indicate that their carrying value may not be fully recoverable (and at least annually for goodwill and indefinite-lived intangible assets), non-financial instruments are assessed for impairment and, if applicable, written down to and recorded at fair value. See Note 12. Goodwill Note 13. Intangible Assets
Cash, Cash Equivalents, and Marketable Securities	Cash, Cash Equivalents, and Marketable Securities Sometimes we invest excess cash in money market funds not insured by the Federal Deposit Insurance Corporation. We believe that the investments in money market funds are on deposit with credit-worthy financial institutions and that the funds are highly liquid. The investments in money market funds are reported at fair value, with interest income recorded in earnings and are included in “Cash and cash equivalents.”
Concentrations of Credit Risk	Concentrations of Credit Risk — We have established an allowance for doubtful accounts based upon factors surrounding the credit risk of specific customers, historical trends, and other information.
Accounts Receivable and Allowance for Doubtful Accounts	Accounts Receivable and Allowance for Doubtful Accounts — Changes in allowance for doubtful accounts are summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 Balances at beginning of period ​ $ 1,856 ​ $ 1,748 Additions from acquisition ​ ​ 1,884 ​ ​ 416 Additions - charged to expense ​ 4,207 ​ 109 Deductions - write-offs, net of recoveries ​ (202) ​ (417) Balances at end of period ​ $ 7,745 ​ $ 1,856 ​
Inventories	Inventories We regularly review inventory quantities on hand and record a provision to write-down excess and obsolete inventory to its estimated net realizable value, if less than cost, based primarily on historical usage and our estimated forecast of product demand. Demand for our products can fluctuate significantly. A significant decrease in demand could result in an increase in the charges for excess inventory quantities on hand. In addition, our industry is subject to technological change, new product development, and product technological obsolescence that could result in an increase in the amount of obsolete inventory quantities on hand. Therefore, any significant unanticipated changes in demand or technological developments could have a significant impact on the value of our inventory and our reported operating results.
Property and Equipment	Property and Equipment 3 Amortization of leasehold improvements is calculated using the straight-line method over the lease term or the estimated useful life of the assets, whichever period is shorter. Leasehold additions and improvements are capitalized, while maintenance and repairs are expensed as incurred. When depreciable assets are retired, or otherwise disposed of, the cost and related accumulated depreciation are removed from the accounts and any related gains or losses are included in other income, net, in our Consolidated Statements of Operations.
Purchase accounting	Purchase accounting
Intangible Assets, Goodwill and Other Long-Lived Assets	Intangible Assets, Goodwill and Other Long-Lived Assets The estimation of useful lives and expected cash flows requires us to make judgments regarding future periods that are subject to some factors outside of our control. Changes in these estimates can result in revisions to our carrying value of these assets and may result in material charges to our results of operations. The annual impairment test for goodwill can be performed using an assessment of qualitative factors in determining if it is more likely than not that goodwill is impaired. If this assessment indicates that it is more likely than not that goodwill is impaired, the next step of impairment testing compares the fair value of a reporting unit to its carrying value. Goodwill would be impaired if the resulting implied fair value of goodwill was less than the recorded carrying value of the goodwill.
Debt Issuance Costs	Debt Issuance Costs Note 22. Credit Facility
Revenue Recognition	Revenue Recognition We maintain a worldwide support organization in 10 countries, including the United States, the PRC, Japan, Korea, Taiwan, Germany, Ireland, Singapore, Israel and Great Britain. 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. As part of our ongoing service business, we satisfy our service obligations under extended warranties and preventive maintenance contracts. Extended warranties had previously been offered on our discontinued inverter products. Any up-front fees received for extended warranties or maintenance plans are deferred and recognized ratably over the service periods, as defined in the agreements.
Research and Development Expenses	Research and Development Expenses
Warranty Costs	Warranty Costs 12 five Note 4. Disposed and Discontinued Operations Note 15. Warranties
Stock-Based Compensation	Stock-Based Compensation
Income Taxes	Income Taxes We assess the recoverability of our net deferred tax assets and the need for a valuation allowance on a quarterly basis. Our assessment includes a number of factors including historical results and taxable income projections for each jurisdiction. The ultimate realization of deferred income tax assets is dependent on the generation of taxable income in appropriate jurisdictions during the periods in which those temporary differences are deductible. We consider the scheduled reversal of deferred income tax liabilities, projected future taxable income, and tax planning strategies in determining the amount of the valuation allowance. Based on the level of historical taxable income and projections for future taxable income over the periods in which the deferred income tax assets are deductible, we determine if we will realize the benefits of these deductible differences. Accounting for income taxes requires a two-step approach to recognize and measure uncertain tax positions. In general, we are subject to regular examination of our income tax returns by the Internal Revenue Service and other tax authorities. The first step is to evaluate the tax position for recognition by determining, if based on the technical merits, it is more likely than not that the position will be sustained upon audit, including resolutions of related appeals or litigation processes, if any. The second step is to measure the tax benefit as the largest amount that is more than 50% likely of being realized upon ultimate settlement. We regularly assess the likelihood of favorable or unfavorable outcomes resulting from these examinations to determine the adequacy of our provision for income taxes. This evaluation is based on factors including, but not limited to, changes in facts or circumstances, changes in tax law, effectively settled issues under audit, and new audit activity. On December 22, 2017, the Tax Act was enacted into law and the new legislation contains several key tax provisions that affected us, including a one-time mandatory transition tax on accumulated foreign earnings and a reduction of the corporate income tax rate to 21%, among others. In conjunction with the Tax Act enactment, the SEC issued Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act
Leases	Leases — Right-of-use assets and operating lease liabilities are recognized at the present value of the future lease payments at the lease commencement date. The interest rate used to determine the present value of the future lease payments is our incremental borrowing rate, because the interest rate implicit in our leases is not readily determinable. Our incremental borrowing rate is estimated to approximate the interest rate on a collateralized basis with similar terms and payments. Our lease terms include periods under options to extend or terminate the lease when it is reasonably certain that we will exercise that option. Right-of-use assets also include any prepaid lease payments and lease incentives. Operating lease expense is recognized on a straight-line basis over the lease term.
Commitments and Contingencies	Commitments and Contingencies these uncertainties in a manner inconsistent with our expectations could have a significant impact on our results of operations and financial condition
New Accounting Standards Adopted	New Accounting Standards Adopted 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 the Tax Act to retained earnings. ASU 2018-02 is effective for fiscal years beginning after December 15, 2018, including interim periods within those years. We adopted ASU 2018-02 during the first quarter of fiscal year 2019 which did not materially impact our Consolidated Financial Statements. In June 2018, the FASB issued ASU 2018-07, "Compensation-Stock Compensation (Topic 718)", Improvements to Non-employee Share-based Payments (“ASU 2018-07”). This ASU expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from non-employees. ASU 2018-07 is effective for fiscal years beginning after December 15, 2018. The new guidance is required to be applied retrospectively with the cumulative effect recognized at the date of initial application. We adopted ASU 2018-07 during the first quarter of fiscal year 2019 which did not materially impact our Consolidated Financial Statements. In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842),” to increase transparency and comparability among organizations by recognizing lease right-of-use 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. We adopted ASU 2016-02 using the modified retrospective approach and recorded $38.2 million of operating lease right-of-use assets and $38.4 million of operating lease liabilities 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. 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.
New Accounting Standards Issued But Not Yet Adopted	New Accounting Standards In June 2016, the FASB issued ASU 2016-13, "Financial Instruments—Credit Losses (Topic 326)", Measurement of Credit Losses on Financial Instruments ("ASU 2016-13"). This ASU changes the methodology for measuring credit losses on financial instruments and the timing of when such losses are recorded. ASU 2016-13 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2019. Early adoption is permitted for fiscal years, and interim periods within those years, beginning after December 15, 2018. We are currently assessing the impact ASU 2016-13 will have on our Consolidated Financial Statements. In August 2018, the FASB issued ASU 2018-13, "Fair Value Measurement (Topic 820)" ("ASU 2018-13"). ASU 2018-13 modifies the disclosure requirements on fair value measurements in Topic 820, Fair Value Measurement, based on the concepts in the Concepts Statement, including the consideration of costs and benefits. ASU 2018-13 is effective for fiscal years ending after December 15, 2019 and shall be applied to all periods presented on a retrospective basis. Early adoption is permitted. We are currently assessing and do not believe ASU 2018-13 will have a significant impact on our fair value measurements disclosure requirements. In August 2018, the FASB issued ASU 2018-14, "Compensation—Retirement Benefits—Defined Benefit Plans—General (Subtopic 715-20)" ("ASU 2018-14"). ASU 2018-14 eliminates requirements for certain disclosures and requires additional disclosures under defined benefit pension plans and other post-retirement plans. ASU 2018-14 is effective for fiscal years ending after December 15, 2020 and shall be applied to all periods presented on a retrospective basis. Early adoption is permitted. We are currently assessing and do not believe ASU 2018-14 will have a significant impact on our defined benefit plan disclosure requirements.

Operations and Summary of Sig_3

Operations and Summary of Significant Accounting Policies and Estimates (Tables)	12 Months Ended
	Dec. 31, 2019
Operations and Summary of Significant Accounting Policies and Estimates
Schedule of changes in allowance for doubtful accounts	Changes in allowance for doubtful accounts are summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 Balances at beginning of period ​ $ 1,856 ​ $ 1,748 Additions from acquisition ​ ​ 1,884 ​ ​ 416 Additions - charged to expense ​ 4,207 ​ 109 Deductions - write-offs, net of recoveries ​ (202) ​ (417) Balances at end of period ​ $ 7,745 ​ $ 1,856

Business Acquisitions (Tables)

Business Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2019
Business Acquisition [Line Items]
Schedule of fair value of assets acquired and liabilities assumed	The final fair values of the assets acquired and liabilities assumed from our acquisitions in 2018 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Electrostatic ​ ​ ​ ​ ​ ​ Trek ​ Product Line ​ LumaSense ​ Total Accounts and other receivable, net ​ $ 2,818 ​ $ 77 ​ $ 7,167 ​ $ 10,062 Inventories ​ 3,941 ​ 292 ​ 9,372 ​ 13,605 Property and equipment ​ 594 ​ 50 ​ 1,353 ​ 1,997 Goodwill ​ — ​ 1,220 ​ 36,258 ​ 37,478 Intangible assets ​ 788 ​ 1,400 ​ 43,240 ​ 45,428 Deferred income tax assets ​ 606 ​ — ​ 6,331 ​ 6,937 Other assets ​ 854 ​ — ​ 6,004 ​ 6,858 Total assets acquired ​ 9,601 ​ 3,039 ​ 109,725 ​ 122,365 Accounts payable ​ 747 ​ 39 ​ 5,734 ​ 6,520 Deferred income tax liabilities ​ — ​ — ​ 11,699 ​ 11,699 Other liabilities ​ 2,782 ​ — ​ 7,608 ​ 10,390 Total liabilities assumed ​ 3,529 ​ 39 ​ 25,041 ​ 28,609 Total fair value of net assets acquired ​ $ 6,072 ​ $ 3,000 ​ $ 84,684 ​ $ 93,756
Schedule of unaudited pro forma information	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2019 ​ 2018 ​ ​ As Reported Pro Forma As Reported Pro Forma Total sales ​ $ 788,948 $ 1,202,790 $ 718,892 $ 1,350,037 Net income attributable to Advanced Energy Industries, Inc. ​ $ 64,941 $ 83,104 $ 147,025 $ 158,422 Earnings per share: ​ ​ ​ ​ ​ Basic earnings per share ​ $ 1.70 ​ $ 2.17 ​ $ 3.76 ​ $ 4.05 Diluted earnings per share ​ $ 1.69 ​ $ 2.16 ​ $ 3.74 ​ $ 4.03
Artesyn's Embedded Power Business [Member]
Business Acquisition [Line Items]
Schedule of components of the fair value of total consideration transferred	The components of the fair value of the total consideration transferred for the acquisition is as follows: ​ ​ ​ ​ ​ ​ ​ Cash paid for acquisition ​ $ 389,326 Non-cash consideration ​ 2,000 Contingent consideration and working capital adjustments ​ ​ (6,848) Total fair value of consideration transferred ​ ​ 384,478 Less cash acquired ​ (23,225) Total purchase price ​ $ 361,253
Schedule of fair value of assets acquired and liabilities assumed	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Preliminary: September 10, 2019 ​ Measurement Period Adjustments ​ Preliminary: December 31, 2019 Accounts and other receivable, net ​ $ 128,221 ​ $ - ​ $ 128,221 Inventories ​ 140,678 ​ ​ (900) ​ ​ 139,778 Property and equipment ​ 65,016 ​ ​ (1,984) ​ ​ 63,032 Operating lease right-of-use assets ​ ​ 60,217 ​ ​ (144) ​ ​ 60,073 Goodwill ​ 143,262 ​ ​ (30,222) ​ ​ 113,040 Intangible assets ​ 125,000 ​ ​ (1,000) ​ ​ 124,000 Deferred income tax assets ​ 14,767 ​ ​ (14,767) ​ ​ — Other assets ​ 61,511 ​ ​ 2,507 ​ ​ 64,018 Total assets acquired ​ 738,672 ​ ​ (46,510) ​ ​ 692,162 Accounts payable ​ 144,652 ​ ​ 50 ​ ​ 144,702 Operating lease liability ​ ​ 59,634 ​ ​ 477 ​ ​ 60,111 Pension liability ​ ​ 48,494 ​ ​ 192 ​ ​ 48,686 Deferred income tax liabilities ​ 37,218 ​ ​ (31,372) ​ ​ 5,846 Other liabilities ​ 80,876 ​ ​ (9,312) ​ ​ 71,564 Total liabilities assumed ​ 370,874 ​ ​ (39,965) ​ ​ 330,909 Total fair value of net assets acquired ​ $ 367,798 ​ $ (6,545) ​ $ 361,253
Summary of intangible assets	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization ​ ​ ​ Artesyn ​ Method ​ Useful Life Technology ​ $ 28,000 ​ Straight-line 5 Customer relationships ​ 75,000 ​ Straight-line 15 Tradename ​ 21,000 ​ Straight-line 10 Total ​ $ 124,000 ​
LumaSense Technology Holdings Inc. [Member]
Business Acquisition [Line Items]
Schedule of components of the fair value of total consideration transferred	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Electrostatic ​ ​ ​ ​ ​ ​ Trek ​ Product Line ​ LumaSense ​ Total Cash paid for acquisition ​ $ 11,723 ​ $ 3,000 ​ $ 94,946 ​ $ 109,669 Less cash acquired ​ (5,651) ​ — ​ (10,262) ​ (15,913) Total purchase price ​ $ 6,072 ​ $ 3,000 ​ $ 84,684 ​ $ 93,756
Schedule of fair value of assets acquired and liabilities assumed	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Preliminary: December 31, 2018 ​ Measurement Period Adjustments ​ Adjusted: December 31, 2019 Accounts and other receivable, net ​ $ 7,167 ​ $ - ​ $ 7,167 Inventories ​ 9,372 ​ ​ - ​ ​ 9,372 Property and equipment ​ 1,353 ​ ​ - ​ ​ 1,353 Goodwill ​ 48,032 ​ ​ (11,774) ​ ​ 36,258 Intangible assets ​ 26,000 ​ ​ 17,240 ​ ​ 43,240 Deferred income tax assets ​ 8,116 ​ ​ (1,785) ​ ​ 6,331 Other assets ​ 5,126 ​ ​ 878 ​ ​ 6,004 Total assets acquired ​ 105,166 ​ ​ 4,559 ​ ​ 109,725 Accounts payable ​ 5,734 ​ ​ - ​ ​ 5,734 Deferred income tax liabilities ​ 7,984 ​ ​ 3,715 ​ ​ 11,699 Other liabilities ​ 6,764 ​ ​ 844 ​ ​ 7,608 Total liabilities assumed ​ 20,482 ​ ​ 4,559 ​ ​ 25,041 Total fair value of net assets acquired ​ $ 84,684 ​ $ - ​ $ 84,684
Summary of intangible assets	A summary of the intangible assets acquired in 2018, amortization method and estimated useful lives are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Method and Useful life ​ ​ ​ ​ Electrostatic ​ ​ ​ Amortization ​ ​ ​ Trek ​ Product Line ​ LumaSense ​ Method ​ Useful Life Technology ​ $ 671 ​ $ 1,200 ​ $ 35,530 ​ Straight-line 10 - 15 Customer relationships ​ 117 ​ 200 ​ 4,360 ​ Straight-line 10 Tradename ​ — ​ — ​ 3,350 ​ Straight-line 10 Total ​ $ 788 ​ $ 1,400 ​ $ 43,240 ​ ​ ​ ​

Revenue (Tables)

Revenue (Tables)	12 Months Ended
	Dec. 31, 2019
Revenue
Schedule of disaggregation of revenue	Disaggregation of Revenue The following table presents our sales by product line, which includes certain reclassifications to prior comparative periods to conform to our current year presentation: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 ​ 2017 ​ Semiconductor Equipment ​ $ 403,018 ​ $ 533,770 ​ $ 554,063 ​ Industrial & Medical ​ 245,992 ​ 185,122 ​ 116,949 ​ Data Center Computing ​ ​ 91,438 ​ ​ — ​ ​ — ​ Telecom & Networking ​ ​ 48,500 ​ ​ — ​ ​ — Total ​ $ 788,948 ​ $ 718,892 ​ $ 671,012 ​ ​ ​ The following table presents our sales by geographic region: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 North America ​ $ 373,634 47.4 % $ 372,834 51.8 % $ 377,347 56.2 % Asia ​ 295,155 37.4 ​ 250,574 34.9 ​ 221,690 33.1 ​ Europe ​ 119,427 15.1 ​ 94,793 13.2 ​ 71,796 10.7 ​ Other ​ 732 0.1 ​ 691 0.1 ​ 179 — ​ Total ​ $ 788,948 100.0 % $ 718,892 100.0 % $ 671,012 100.0 % ​ 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: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Product and service revenue recognized at point in time ​ $ 786,918 ​ $ 715,055 ​ $ 667,440 Extended warranty and service contracts recognized over time ​ 2,030 ​ 3,837 ​ 3,572 Total ​ $ 788,948 ​ $ 718,892 ​ $ 671,012

Disposed and Discontinued Ope_2

Disposed and Discontinued Operations (Tables)	12 Months Ended
	Dec. 31, 2019
Disposed and Discontinued Operations
Schedule of disposal groups, including discontinued operations	The significant items included in "Income (loss) from discontinued operations, net of income taxes" are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 Sales ​ $ — ​ $ — Cost of sales ​ (901) ​ (88) Total operating expense ​ 1,022 ​ 96 Operating income (loss) from discontinued operations ​ (121) ​ (8) Other income (expense) ​ 10,895 ​ (24) Income (loss) from discontinued operations before income taxes ​ 10,774 ​ (32) Provision (benefit) for income taxes ​ 2,294 ​ 6 Income (loss) from discontinued operations, net of income taxes ​ $ 8,480 ​ $ (38) ​ Assets and Liabilities of discontinued operations within the Consolidated Balance Sheets are comprised of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2019 2018 Cash and cash equivalents ​ $ — ​ $ 5,251 Accounts and other receivables, net ​ ​ — ​ ​ 406 Inventories ​ ​ 30 ​ ​ 198 Current assets of discontinued operations ​ ​ 30 ​ ​ 5,855 Other assets ​ ​ — ​ ​ 67 Deferred income tax assets ​ 269 ​ 5,917 Non-current assets of discontinued operations ​ ​ 269 ​ ​ 5,984 Accounts payable and other accrued expenses ​ ​ — ​ ​ 350 Accrued warranty ​ 914 ​ 4,936 Current liabilities of discontinued operations ​ ​ 914 ​ ​ 5,286 Accrued warranty ​ ​ 698 ​ ​ 10,429 Other liabilities ​ 189 ​ 286 Non-current liabilities of discontinued operations ​ $ 887 ​ $ 10,715

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Income Taxes
Schedule of geographic distribution of pretax income from continuing operations	The geographic distribution of pretax income from continuing operations is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Domestic ​ $ (20,597) ​ $ 22,325 ​ $ 29,088 Foreign ​ 87,791 ​ 150,051 ​ 169,103 ​ ​ $ 67,194 ​ $ 172,376 ​ $ 198,191
Schedule of tax expense and the effective tax rate for our income from continuing operations	The provision for income taxes from continuing operations is summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Current: ​ ​ ​ Federal ​ $ (9,627) ​ $ 1,423 ​ $ 26,550 State ​ 882 ​ 12 ​ 601 Foreign ​ 18,429 ​ 13,772 ​ 9,621 Total current provision ​ $ 9,684 ​ $ 15,207 ​ $ 36,772 Deferred: ​ ​ ​ Federal ​ $ 3,822 ​ $ 4,021 ​ $ 28,297 State ​ (178) ​ 2,363 ​ (1,000) Foreign ​ (2,629) ​ 3,636 ​ (1,979) Total deferred provision ​ 1,015 ​ 10,020 ​ 25,318 Total provision for income taxes ​ $ 10,699 ​ $ 25,227 ​ $ 62,090
Schedule of effective income tax rate reconciliation	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 ​ 2018 ​ 2017 Income taxes per federal statutory rate ​ $ 14,111 ​ $ 36,199 ​ $ 69,348 State income taxes, net of federal deduction ​ ​ 10 ​ ​ 2,372 ​ ​ 1,794 Transition tax - U.S. Tax Reform ​ ​ — ​ ​ 1,174 ​ ​ 61,690 Corporate tax rate changes - U.S. Tax Reform ​ ​ — ​ ​ (652) ​ ​ 11,177 Tax benefit associated with inverter business wind down ​ ​ — ​ ​ — ​ ​ (33,837) Stock based compensation ​ ​ (97) ​ ​ (974) ​ ​ (5,263) GILTI Tax ​ ​ 8,796 ​ ​ 13,064 ​ ​ — Tax effect of foreign operations ​ ​ (13,086) ​ ​ (19,162) ​ ​ (47,482) Uncertain tax position ​ ​ (4,487) ​ ​ (3,088) ​ ​ 4,948 Unremitted earnings ​ ​ 1,624 ​ ​ 2,564 ​ ​ — Tax credits ​ ​ (6,280) ​ ​ (9,844) ​ ​ (658) Change in valuation allowance ​ ​ 7,222 ​ ​ (1,306) ​ ​ 841 Withholding taxes ​ ​ 6,500 ​ ​ 1,371 ​ ​ — Other permanent items, net ​ ​ (3,614) ​ ​ 3,509 ​ ​ (468) Total provision for income taxes ​ $ 10,699 ​ $ 25,227 ​ $ 62,090
Schedule of deferred tax assets and liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 Deferred tax assets ​ ​ Stock based compensation ​ $ 1,757 ​ $ 1,337 Net operating loss and tax credit carryforwards ​ 86,879 ​ 38,622 Interest expense limitation ​ ​ 7,620 ​ ​ — Pension obligation ​ 13,473 ​ 3,302 Excess and obsolete inventory ​ 3,217 ​ 2,161 Deferred revenue ​ 3,305 ​ 6,903 Employee bonuses and commissions ​ 2,537 ​ 1,874 Depreciation and amortization ​ 29,015 ​ 29,525 Operating lease liabilities ​ ​ 23,451 ​ ​ — Other ​ 9,685 ​ 9,961 Deferred tax assets ​ 180,939 ​ 93,685 Less: Valuation allowance ​ (76,206) ​ (30,924) Net deferred tax assets ​ 104,733 ​ 62,761 Deferred tax liabilities ​ ​ Depreciation and amortization ​ 41,549 ​ 17,723 Unremitted earnings ​ 4,740 ​ 3,529 Operating lease right-of-use assets ​ ​ 22,774 ​ ​ — Other ​ 2,966 ​ 1,267 Deferred tax liabilities ​ 72,029 ​ 22,519 Net deferred tax assets ​ $ 32,704 ​ $ 40,242
Summary of income tax contingencies	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Balance at beginning of period ​ $ 13,162 ​ $ 15,990 ​ $ 11,401 Additions based on tax positions taken during a prior period ​ 484 ​ 94 ​ 1,258 Additions based on tax positions taken during a prior period - acquisitions ​ 4,479 ​ 757 ​ — Additions based on tax positions taken during the current period ​ — ​ — ​ 4,433 Reductions based on tax positions taken during a prior period ​ (4,295) ​ (153) ​ — Reductions related to a lapse of applicable statute of limitations ​ (821) ​ (3,144) ​ (1,102) Reductions related to a settlement with taxing authorities ​ — ​ (382) ​ — Balance at end of period ​ $ 13,009 ​ $ 13,162 ​ $ 15,990

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2019
Earnings Per Share
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 earnings per share for the years ended December 31, 2019, 2018 and 2017: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Income from continuing operations ​ $ 56,495 ​ $ 147,149 ​ $ 136,101 Income from continuing operations attributable to noncontrolling interest ​ 34 ​ 86 ​ — Income from continuing operations attributable to Advanced Energy Industries, Inc. ​ $ 56,461 ​ $ 147,063 ​ $ 136,101 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic weighted-average common shares outstanding ​ 38,281 ​ 39,081 ​ 39,754 Assumed exercise of dilutive stock options and restricted stock units ​ 214 ​ 271 ​ 422 Diluted weighted-average common shares outstanding ​ 38,495 ​ 39,352 ​ 40,176 Continuing operations: ​ ​ ​ Basic earnings per share ​ $ 1.47 ​ $ 3.76 ​ $ 3.42 Diluted earnings per share ​ $ 1.47 ​ $ 3.74 ​ $ 3.39
Schedule of stock options and restricted units excluded in the computation of diluted earnings per share	The following stock options and restricted units were excluded in the computation of diluted earnings per share because they were anti-dilutive: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Restricted stock units — 2 —
Schedule of repurchase of shares of common stock	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ (in thousands, except per share amounts) ​ 2019 2018 2017 Amount paid to repurchase shares ​ $ — ​ $ 95,125 ​ $ 29,993 Number of shares repurchased ​ — ​ 1,696 ​ 422 Average repurchase price per share ​ $ — ​ $ 56.07 ​ $ 71.07

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2019
Derivative Financial Instruments
Schedule of derivative instruments gains and losses	During the years ended December 31, 2019, 2018, and 2017, the gains and losses recorded related to the foreign currency exchange rate forward contracts are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Foreign currency loss from foreign currency exchange rate forward contracts ​ $ — ​ $ (750) ​ $ (1,438)

Accounts and Other Receivable (

Accounts and Other Receivable (Tables)	12 Months Ended
	Dec. 31, 2019
Accounts and Other Receivable
Schedule of 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: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ 2019 2018 Amounts billed, net ​ $ 227,528 ​ $ 80,709 Unbilled receivables ​ ​ 19,036 ​ 19,733 Total receivables, net ​ $ 246,564 ​ $ 100,442

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2019
Inventories
Schedule of 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 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2019 2018 Parts and raw materials ​ $ 134,816 ​ $ 76,647 Work in process ​ 10,269 ​ 6,644 Finished goods ​ 84,934 ​ 14,696 Total ​ $ 230,019 ​ $ 97,987

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2019
Property and Equipment, Net
Schedule of details of property and equipment	Property and equipment, net is comprised of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2019 2018 Buildings and land ​ $ 1,693 ​ $ 1,737 Machinery and equipment ​ 108,945 ​ 41,330 Computer and communication equipment ​ 29,106 ​ 24,051 Furniture and fixtures ​ 4,119 ​ 3,203 Vehicles ​ 262 ​ 282 Leasehold improvements ​ 33,041 ​ 20,593 Construction in process ​ 9,089 ​ 867 ​ ​ 186,255 ​ 92,063 Less: Accumulated depreciation ​ (78,146) ​ (60,794) Property and equipment, net ​ $ 108,109 ​ $ 31,269
Schedule of depreciation expense recorded in continuing operations	Depreciation expense is recorded in continuing operations and allocated within Cost of Sales, Research and development expense and Selling, general and administrative expense in our Consolidated Statements of Operations as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Depreciation expense ​ $ 13,979 ​ $ 7,818 ​ $ 5,074

Goodwill (Tables)

Goodwill (Tables)	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets
Schedule of the changes in goodwill	The following summarizes the changes in goodwill during the years ended December 31, 2019 and 2018: ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2017 ​ $ 53,812 Measurement period adjustments to preliminary purchase price allocation ​ ​ — Additions from acquisition ​ ​ 49,252 Foreign currency translation ​ ​ (1,164) December 31, 2018 ​ ​ 101,900 Measurement period adjustments to preliminary purchase price allocation ​ ​ (41,996) Additions from acquisition ​ ​ 143,262 Foreign currency translation ​ ​ (234) December 31, 2019 ​ $ 202,932

Intangible Assets (Tables)

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets
Schedule of intangible assets	Intangible assets consisted of the following as of December 31, 2019 and 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Carrying Accumulated Net Carrying December 31, 2019 ​ Amount ​ Amortization ​ Amount Technology ​ $ 83,368 ​ $ (14,250) ​ $ 69,118 Customer relationships ​ 108,995 ​ (18,197) ​ 90,798 Trademarks and other ​ 26,888 ​ (2,793) ​ 24,095 Total ​ $ 219,251 ​ $ (35,240) ​ $ 184,011 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Carrying Accumulated Net Carrying December 31, 2018 ​ Amount ​ Amortization ​ Amount Technology ​ $ 39,879 ​ $ (7,927) ​ $ 31,952 Customer relationships ​ 35,509 ​ (13,484) ​ 22,025 Trademarks and other ​ 2,501 ​ (1,568) ​ 933 Total ​ $ 77,889 ​ $ (22,979) ​ $ 54,910
Schedule of amortization expense related to intangible assets	Amortization expense related to intangible assets is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Amortization expense ​ $ 12,168 ​ $ 5,774 ​ $ 4,350
Schedule of estimated amortization expense related to intangible assets	Estimated amortization expense related to intangibles is as follows: ​ ​ ​ ​ Year Ending December 31, ​ ​ 2020 ​ $ 20,109 2021 ​ 20,009 2022 ​ 19,745 2023 ​ 19,727 2024 ​ 16,888 Thereafter ​ 87,533 Total ​ $ 184,011

Restructuring Costs (Tables)

Restructuring Costs (Tables)	12 Months Ended
	Dec. 31, 2019
Restructuring Costs
Schedule of restructuring charges	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cumulative Cost ​ ​ ​ ​ ​ ​ ​ ​ Through December 31, ​ ​ 2019 ​ ​ 2018 ​ ​ 2019 Severance and related charges $ 3,041 ​ $ 4,239 ​ $ 7,280 Facility relocation and closure charges 1,996 ​ — ​ 1,996 Total restructuring charges $ 5,038 ​ $ 4,239 ​ $ 9,277
Schedule of restructuring liabilities	The following table summarizes our restructuring liabilities at December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cost ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Incurred ​ Cost Paid ​ Effect of ​ ​ ​ ​ ​ Balance at ​ and ​ or ​ Changes in ​ Balance at ​ ​ December 31, ​ Charged to ​ Otherwise ​ Exchange ​ December 31, ​ ​ 2018 ​ Expense ​ Settled ​ Rates ​ 2019 Total restructuring liabilities ​ $ 3,806 ​ $ 5,038 ​ $ (6,673) ​ $ 1 ​ $ 2,172

Warranties (Tables)

Warranties (Tables)	12 Months Ended
	Dec. 31, 2019
Warranties
Schedule of changes in accrued product warranties	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Balances at beginning of period ​ $ 2,084 ​ $ 2,312 ​ $ 2,329 Warranty acquired in business combinations ​ 4,818 ​ 305 ​ 118 Increases to accruals ​ 1,752 ​ 1,606 ​ 2,029 Warranty expenditures ​ (2,249) ​ (2,127) ​ (2,184) Effect of changes in exchange rates ​ 8 ​ (12) ​ 20 Balances at end of period ​ $ 6,413 ​ $ 2,084 ​ $ 2,312

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2019
Leases
Components of operating lease cost	​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, 2019 Operating lease cost $ 11,052 ​ Short-term and variable lease cost ​ 4,726 ​ Total operating lease cost $ 15,778 ​
Schedule of maturities of lease liabilities	Maturities of our lease liabilities for all operating leases at December 31, 2019 are as follows: ​ ​ ​ ​ ​ Year Ending December 31, ​ 2020 ​ $ 22,351 2021 ​ 19,771 2022 ​ 13,503 2023 ​ 10,786 2024 ​ ​ 9,601 Thereafter ​ ​ 56,355 Total lease payments ​ ​ 132,367 Less: Interest ​ ​ (23,517) Present value of lease liabilities ​ $ 108,850
Schedule of other information related to leases	Other information related to leases, including supplemental cash flow information, consists of: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ December 31, 2019 Weighted average remaining lease term (in years) ​ ​ ​ 7.50 ​ Weighted average discount rate ​ ​ ​ 4.05 % Cash paid for operating leases ​ ​ $ 12,101 ​ Right-of-use assets obtained in exchange for operating lease liabilities (1) ​ ​ $ 84,551 ​
Schedule of future minimum lease payments under operating leases	Future minimum lease payments under operating leases were: ​ ​ ​ ​ Year Ending December 31, ​ 2019 ​ $ 9,093 2020 ​ 7,561 2021 ​ 6,938 2022 ​ 3,862 2023 ​ ​ 3,448 Thereafter ​ 18,349 Total lease payments ​ $ 49,251

Employee Retirement Plans and_2

Employee Retirement Plans and Postretirement Benefits (Tables)	12 Months Ended
	Dec. 31, 2019
Employee Retirement Plans and Postretirement Benefits
Changes in projected benefit obligations and plan assets	The Company’s projected benefit obligation and plan assets for defined benefit pension plans at December 31, 2019 and 2018 and the related assumptions used to determine the related liabilities are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 Projected benefit obligation, beginning of year ​ $ 33,178 ​ $ 34,498 Acquisition ​ 48,350 ​ 1,063 Service cost ​ 272 ​ 841 Interest cost ​ 1,211 ​ 802 Actuarial loss ​ (193) ​ (988) Benefits paid ​ (1,779) ​ (1,113) Translation adjustment ​ 2,223 ​ (1,925) Projected benefit obligation, end of year ​ $ 83,262 ​ $ 33,178 Fair value of plan assets, beginning of year ​ $ 13,433 ​ $ 14,181 Acquisitions ​ 102 ​ 981 Actual return on plan assets ​ 380 ​ 675 Contributions ​ 644 ​ 828 Benefits paid ​ (1,176) ​ (1,086) Actuarial gain ​ 1,064 ​ (1,357) Translation adjustment ​ 456 ​ (789) Fair value of plan assets, end of year ​ $ 14,903 ​ $ 13,433 Funded status of plan ​ $ (68,359) ​ $ (19,745)
Schedule of net periodic pension benefit costs	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Service cost ​ $ 272 ​ $ 841 ​ $ — Interest cost ​ ​ 1,211 ​ ​ 802 ​ ​ 809 Expected return on plan assets ​ (615) ​ (665) ​ (597) Amortization of actuarial gains and losses ​ 411 ​ 478 ​ 503 Net periodic pension cost ​ $ 1,279 ​ $ 1,456 ​ $ 715
Schedule of assumptions used in determination of net period pension cost	Assumptions used in the determination of the net periodic pension cost are: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Discount rate 2.7 % 2.8 % 2.6 % Expected long-term return on plan assets 4.6 % 4.8 % 4.8 % ​ The fair value of the Company’s qualified pension plan assets by category for the years ended December 31, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ Level 1 Level 2 Level 3 Total Multi-Asset Fund ​ $ — ​ $ 4,825 ​ $ — ​ $ 4,825 Diversified Growth Fund ​ — ​ 4,855 ​ — ​ 4,855 Index-Linked Gilts ​ — ​ 1,934 ​ — ​ 1,934 Corporate Bonds ​ — ​ 2,090 ​ — ​ 2,090 Insurance Contracts ​ ​ — ​ — ​ 1,045 ​ 1,045 Cash ​ 154 ​ — ​ — ​ 154 Total ​ $ 154 ​ $ 13,704 ​ $ 1,045 ​ $ 14,903 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2018 ​ Level 1 Level 2 Level 3 Total Multi-Asset Fund ​ $ — ​ $ 4,570 ​ $ — ​ $ 4,570 Diversified Growth Fund ​ — ​ 4,650 ​ — ​ 4,650 Index-Linked Gilts ​ — ​ 2,044 ​ — ​ 2,044 Corporate Bonds ​ — ​ 2,044 ​ — ​ 2,044 Insurance Contracts ​ ​ — ​ ​ — ​ ​ 72 ​ ​ 72 Cash ​ 53 ​ — ​ — ​ 53 Total ​ $ 53 ​ $ 13,308 ​ $ 72 ​ $ 13,433
Schedule of fair value qualified pension plan assets	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Discount rate 2.7 % 2.8 % 2.6 % Expected long-term return on plan assets 4.6 % 4.8 % 4.8 %
Schedule of expected future benefit payments under defined benefit pension plans	Expected future payments under defined benefit pension plans, based on foreign exchange rates as of December 31, 2019, are as follows: ​ ​ ​ ​ Expected Future Benefit Payments ​ ​ ​ 2020 $ 6,113 2021 ​ ​ 7,039 2022 ​ ​ 5,673 2023 ​ ​ 5,716 2024 ​ ​ 14,487 Thereafter ​ ​ 134,802

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2019
Schedule of stock-based compensation	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Stock-based compensation expense ​ $ 7,327 ​ $ 9,703 ​ $ 12,549
Disclosure of compensation related costs	Changes in the unvested RSU’s during the years ended December 31, 2019, 2018 and 2017 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2019 ​ 2018 ​ 2017 ​ ​ ​ Weighted- ​ Weighted- ​ Weighted- ​ ​ ​ ​ Average ​ ​ ​ Average ​ ​ ​ Average ​ ​ ​ ​ Grant ​ ​ ​ Grant ​ ​ ​ Grant ​ ​ Shares ​ Value ​ Shares ​ Value ​ Shares ​ Value RSUs outstanding at beginning of period 352 ​ $ 58.17 386 ​ $ 51.06 354 ​ $ 29.60 RSUs granted 380 ​ 52.24 245 ​ 64.48 252 ​ 63.63 RSUs vested (155) ​ 50.95 (207) ​ 54.94 (211) ​ 30.62 RSUs forfeited (43) ​ 51.82 (72) ​ 50.79 (9) ​ 33.91 RSUs outstanding at end of period 534 ​ $ 56.56 352 ​ $ 58.17 386 ​ $ 51.06
Schedule of shares authorized under stock option plans, by exercise price range	The following table summarizes information about the stock options outstanding at December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding ​ Options Exercisable ​ ​ ​ ​ Weighted-Average ​ Weighted- ​ ​ ​ Weighted- ​ ​ Number ​ Remaining ​ Average ​ Number ​ Average Range of Exercise Prices Outstanding Contractual Life Exercise Price Exercisable Exercise Price 9.51 - 13.85 23 1.42 years ​ $ 12.00 23 ​ $ 12.00 14.21 - 16.25 20 0.72 years ​ 15.06 20 ​ 15.06 18.77 - 18.77 43 4.75 years ​ 18.77 43 ​ 18.77 26.32 - 26.32 99 5.10 years ​ 26.32 99 ​ 26.32 9.51 - 26.32 185 4.09 years ​ $ 21.56 185 ​ $ 21.56
Employee Stock [Member]
Schedule of valuation assumptions	The fair value of each purchase right granted under the ESPP was estimated on the date of grant using the Black-Scholes-Merton option pricing model with the following assumptions: ​ ​ ​ ​ ​ ​ ​ ​ ​ 2019 2018 2017 Risk-free interest rates 1.62% - 2.31 % 2.10% - 2.56 % 1.07% - 1.45 % Expected dividend yield rates — % — % — % Expected term 0.5 years 0.5 years 0.5 years ​ Expected volatility 41.3 % 38.0 % 33.3 %
Time Based [Member]
Schedule of stock options roll forward	Changes in our outstanding stock options during the years ended December 31, 2019, 2018 and 2017 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2019 ​ 2018 ​ 2017 ​ ​ ​ Weighted- ​ Weighted- ​ Weighted- ​ ​ ​ ​ Average ​ ​ ​ Average ​ ​ ​ Average ​ ​ ​ ​ Exercise ​ ​ ​ Exercise ​ ​ ​ Exercise ​ ​ Shares ​ Price ​ Shares ​ Price ​ Shares ​ Price Options outstanding at beginning of period 230 ​ $ 20.73 317 ​ $ 18.97 474 ​ $ 17.47 Options exercised (42) ​ 17.73 (83) ​ 14.41 (152) ​ 14.32 Options forfeited — ​ — — ​ — (2) ​ 26.32 Options expired (3) ​ 9.91 (4) ​ 11.97 (3) ​ 11.09 Options outstanding at end of period 185 ​ $ 21.56 230 ​ $ 20.73 317 ​ $ 18.97 Options vested during the year — ​ 2 ​ 9 ​
Schedule of restricted stock and restricted stock units activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding ​ Options Exercisable ​ ​ ​ ​ Weighted-Average ​ Weighted- ​ ​ ​ Weighted- ​ ​ Number ​ Remaining ​ Average ​ Number ​ Average Range of Exercise Prices Outstanding Contractual Life Exercise Price Exercisable Exercise Price 9.51 - 13.85 23 1.42 years ​ $ 12.00 23 ​ $ 12.00 14.21 - 16.25 20 0.72 years ​ 15.06 20 ​ 15.06 18.77 - 18.77 43 4.75 years ​ 18.77 43 ​ 18.77 26.32 - 26.32 99 5.10 years ​ 26.32 99 ​ 26.32 9.51 - 26.32 185 4.09 years ​ $ 21.56 185 ​ $ 21.56

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2019
Related Party Transactions
Schedule of related party transactions	During the years ended December 31, 2019, 2018, and 2017, we engaged in the following transactions with companies related to members of our Board of Directors, as described below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Sales to related parties ​ $ 1,340 ​ $ 1,028 ​ $ 1,425 Number of related party customers ​ 1 ​ 1 ​ 1 ​ Our accounts receivable balance from related party customers with outstanding balances as of December 31, 2019 and December 31, 2018 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ 2019 2018 Accounts receivable from related parties ​ $ — ​ $ 109 Number of related party customers ​ 1 ​ 1

Geographic and Significant Cu_2

Geographic and Significant Customer Information (Tables)	12 Months Ended
	Dec. 31, 2019
Geographic and Significant Customer Information
Schedules of concentration of risk, by risk factor	The following table summarizes sales, and percentages of sales, by customers that individually accounted for 10% or more of our sales for the years ended December 31, 2019 and 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 Applied Materials, Inc. ​ $ 164,724 20.9 % $ 258,027 35.9 % LAM Research ​ 88,251 11.2 % 109,005 15.2 % ​ 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 December 31, 2019 and December 31, 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 ​ 2018 Applied Materials, Inc. ​ $ 36,849 14.9 % $ 34,301 34.2 % Nidec Motor Corporation ​ ​ 38,071 ​ 15.4 ​ ​ * * % LAM Research ​ * * % 12,181 12.1 %
Schedule of long-lived assets by geographic area	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2019 2018 United States ​ $ 239,511 ​ $ 115,869 Asia ​ 301,020 ​ 12,274 Europe ​ 59,925 ​ 59,936 Total ​ $ 600,456 ​ $ 188,079

Credit Facility (Tables)

Credit Facility (Tables)	12 Months Ended
	Dec. 31, 2019
Credit Facility
Schedule of debt obligation	​ ​ ​ ​ ​ ​ ​ ​ ​ Debt: ​ Amount Term Loan Facility ​ $ 341,250 Less: debt issuance costs ​ ​ (2,223) Total debt ​ ​ 339,027 Less current portion of debt ​ ​ (17,500) Total long-term debt ​ $ 321,527
Schedule of contractual maturities of the Company's debt obligations	​ ​ ​ ​ ​ ​ Amount 2020 ​ $ 17,500 2021 ​ ​ 17,500 2022 ​ ​ 17,500 2023 ​ ​ 17,500 2024 ​ ​ 271,250 Total ​ $ 341,250
Schedule of interest expense and unused line of credit fees	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 2017 Interest expense ​ $ 2,994 ​ $ — ​ $ — Amortization of debt issuance costs ​ ​ 186 ​ ​ — ​ ​ — Unused line of credit fees and other ​ ​ 236 ​ ​ 228 ​ ​ 66 Total interest expense ​ $ 3,416 ​ $ 228 ​ $ 66

Supplemental Quarterly Financ_2

Supplemental Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2019
Supplemental Quarterly Financial Data
Schedule of quarterly financial data	The following tables present unaudited quarterly results for each of the eight quarters in the periods ended December 31, 2019 and 2018, in thousands. We believe that all necessary adjustments have been included in the amounts stated below to present fairly such quarterly information. Due to the volatility of the industries in which our customers operate, the operating results for any quarter are not necessarily indicative of results for any subsequent period. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quarter Ended ​ December 31, September 30, June 30, March 31, ​ ​ 2019 ​ 2019 ​ 2019 ​ 2019 Sales, net ​ $ 338,268 ​ $ 175,127 ​ $ 134,810 ​ $ 140,743 Gross Profit ​ $ 112,295 ​ $ 73,491 ​ $ 64,126 ​ $ 65,740 Restructuring Expense ​ $ 1,418 ​ $ 152 ​ $ 1,795 ​ $ 1,673 Operating income ​ $ 22,202 ​ $ 9,390 ​ $ 11,005 ​ $ 11,791 Income from continuing operations, net of income taxes ​ $ 10,479 ​ $ 7,256 ​ $ 23,373 ​ $ 15,387 Loss (income) from discontinued operations, net of income taxes ​ $ (210) ​ $ 375 ​ $ 8,324 ​ $ (9) Net Income ​ $ 10,269 ​ $ 7,631 ​ $ 31,697 ​ $ 15,378 Income from continuing operations attributable to noncontrolling interest ​ $ 5 ​ $ 10 ​ $ 11 ​ $ 8 Net income attributable to Advanced Energy Industries, Inc. ​ $ 10,264 ​ $ 7,621 ​ $ 31,686 ​ $ 15,370 Earnings (Loss) Per Share: ​ ​ ​ ​ Continuing Operations: ​ ​ ​ ​ Basic earnings per share ​ $ 0.27 ​ $ 0.19 ​ $ 0.61 ​ $ 0.40 Diluted earnings per share ​ $ 0.27 ​ $ 0.19 ​ $ 0.61 ​ $ 0.40 Discontinued Operations: ​ ​ ​ ​ Basic loss per share ​ $ (0.01) ​ $ 0.01 ​ $ 0.22 ​ $ — Diluted loss per share ​ $ (0.01) ​ $ 0.01 ​ $ 0.22 ​ $ — Net Income: ​ ​ ​ ​ Basic earnings per share ​ $ 0.27 ​ $ 0.20 ​ $ 0.83 ​ $ 0.40 Diluted earnings per share ​ $ 0.27 ​ $ 0.20 ​ $ 0.82 ​ $ 0.40 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quarter Ended ​ December 31, September 30, June 30, March 31, ​ ​ 2018 ​ 2018 ​ 2018 ​ 2018 Sales, net ​ $ 154,161 ​ $ 173,082 ​ $ 196,032 ​ $ 195,617 Gross Profit ​ $ 75,188 ​ $ 85,539 ​ $ 101,235 ​ $ 103,645 Restructuring Expense ​ $ 3,836 ​ $ 403 ​ $ — ​ $ — Operating income ​ $ 19,570 ​ $ 39,862 ​ $ 56,018 ​ $ 56,103 Income from continuing operations, net of income taxes ​ $ 19,222 ​ $ 35,157 ​ $ 46,400 ​ $ 46,370 Income (loss) from discontinued operations, net of income taxes ​ $ 188 ​ $ (371) ​ $ 5 ​ $ 140 Net Income ​ $ 19,410 ​ $ 34,786 ​ $ 46,405 ​ $ 46,510 Income from continuing operations attributable to noncontrolling interest ​ $ 4 ​ $ 7 ​ $ 44 ​ $ 31 Net income attributable to Advanced Energy Industries, Inc. ​ $ 19,406 ​ $ 34,779 ​ $ 46,361 ​ $ 46,479 Earnings (Loss) Per Share: ​ $ ​ ​ ​ Continuing Operations: ​ ​ ​ ​ Basic earnings per share ​ $ 0.50 ​ $ 0.90 ​ $ 1.18 ​ $ 1.17 Diluted earnings per share ​ $ 0.50 ​ $ 0.90 ​ $ 1.17 ​ $ 1.16 Discontinued Operations: ​ ​ ​ ​ Basic loss per share ​ $ — ​ $ (0.01) ​ $ — ​ $ — Diluted loss per share ​ $ — ​ $ (0.01) ​ $ — ​ $ — Net Income: ​ ​ ​ ​ ​ Basic earnings per share ​ $ 0.51 ​ $ 0.89 ​ $ 1.18 ​ $ 1.17 Diluted earnings per share ​ $ 0.50 ​ $ 0.89 ​ $ 1.17 ​ $ 1.16

Operations and Summary of Sig_4

Operations and Summary of Significant Accounting Policies and Estimates - Fair Value (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)item
Operations and Summary of Significant Accounting Policies and Estimates
Number of operating vertical markets | item	4
Transfers of financial assets into or from Level 3	$ 0
Transfers of financial liabilities into or from Level 3	$ 0

Operations and Summary of Sig_5

Operations and Summary of Significant Accounting Policies and Estimates - Summary of Changes in Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Operations and Summary of Significant Accounting Policies and Estimates
Increase in allowance for doubtful accounts	$ 4,200
Balances at beginning of period	1,856	$ 1,748
Additions from acquisition	1,884	416
Additions - charged to expense	4,207	109
Deductions - write-offs, net of recoveries	(202)	(417)
Balances at end of period	$ 7,745	$ 1,856

Operations and Summary of Sig_6

Operations and Summary of Significant Accounting Policies and Estimates - Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2019
Building [Member] | Minimum
Property, Plant and Equipment, Useful Life	20 years
Building [Member] | Maximum
Property, Plant and Equipment, Useful Life	40 years
Machinery, equipment, furniture and fixtures and vehicles [Member]
Property, Plant and Equipment, Useful Life	3 years
Machinery, equipment, furniture and fixtures and vehicles [Member] | Minimum
Property, Plant and Equipment, Useful Life	3 years
Machinery, equipment, furniture and fixtures and vehicles [Member] | Maximum
Property, Plant and Equipment, Useful Life	15 years
Computer and Communication Equipment [Member]
Property, Plant and Equipment, Useful Life	3 years

Operations and Summary of Sig_7

Operations and Summary of Significant Accounting Policies and Estimates - Revenue Recognition and Warrant Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Contract liabilities related to extended warranties and service contracts	$ 9.2	$ 33.4
Precision Power Products [Member] | Minimum
Warranty period	12 months
Precision Power Products [Member] | Maximum
Warranty period	24 months
Inverter Products [Member] | Minimum
Warranty period	5 years
Inverter Products [Member] | Maximum
Warranty period	10 years
Building [Member] | Inverter Products [Member] | Maximum
Additional warranty period	20 years

Operations and Summary of Sig_8

Operations and Summary of Significant Accounting Policies and Estimates - Income Taxes (Details)	1 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operations and Summary of Significant Accounting Policies and Estimates
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	21.00%	35.00%

Operations and Summary of Sig_9

Operations and Summary of Significant Accounting Policies and Estimates - New Accounting Standards (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Mar. 31, 2019
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Operating lease right-of-use assets	$ 105,404
Operating Lease, Liability	$ 108,850
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Liabilities
Accounting Standards Update 2016-02 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Operating lease right-of-use assets	$ 105,400
Operating Lease, Liability	$ 108,900
Accounting Standards Update 2016-02 [Member] | Measurement Period Adjustments [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Operating lease right-of-use assets		$ 38,200
Operating Lease, Liability		$ 38,400

Business Acquisitions - 2019 Ac

Business Acquisitions - 2019 Acquisitions (Details) - USD ($) $ in Thousands	1 Months Ended				4 Months Ended	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	May 31, 2018	Feb. 28, 2018	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Feb. 01, 2018
Business Acquisition [Line Items]
Purchase price							$ 93,756
Effective federal statutory tax rate	21.00%					21.00%	21.00%	35.00%
Cash paid for acquisition							$ 109,669
Revolving Facility [Member]
Business Acquisition [Line Items]
Line of credit facility, borrowing capacity	$ 500,000
Term Loan Facility [Member]
Business Acquisition [Line Items]
Line of credit facility, borrowing capacity	350,000
Artesyn's Embedded Power Business [Member]
Business Acquisition [Line Items]
Purchase price	$ 361,300				$ 361,253	$ 361,253
Cash paid for acquisition					389,326
LumaSense Technology Holdings Inc. [Member]
Business Acquisition [Line Items]
Purchase price					$ 84,684	$ 84,684	84,684
Cash paid for acquisition		$ 84,700					94,946
Electrostatic Product Line [Member] [Member]
Business Acquisition [Line Items]
Purchase price							3,000
Cash paid for acquisition			$ 3,000				3,000
Trek Holding [Member]
Business Acquisition [Line Items]
Purchase price							6,072
Cash paid for acquisition				$ 6,100			$ 11,723
Trek Holding Co., LTD [Member] | Trek Holding Co., LTD [Member] | Trek Holding Co., LTD [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent									95.00%

Business Acquisitions - Schedul

Business Acquisitions - Schedule of Components of Fair Value of Consideration Transferred (Details) - USD ($) $ in Thousands	1 Months Ended			4 Months Ended	12 Months Ended
	Sep. 30, 2018	May 31, 2018	Feb. 28, 2018	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019
Business Acquisition [Line Items]
Cash paid for acquisition					$ 109,669
Less cash acquired					(15,913)
Total purchase price					93,756
Artesyn's Embedded Power Business [Member]
Business Acquisition [Line Items]
Cash paid for acquisition				$ 389,326
Non-cash consideration				2,000
Contingent consideration and working capital adjustments				(6,848)
Total fair value of consideration received				384,478
Less cash acquired				(23,225)
Total purchase price				361,253		$ 361,300
Trek Holding [Member]
Business Acquisition [Line Items]
Cash paid for acquisition			$ 6,100		11,723
Less cash acquired					(5,651)
Total purchase price					6,072
Electrostatic Product Line [Member] [Member]
Business Acquisition [Line Items]
Cash paid for acquisition		$ 3,000			3,000
Total purchase price					3,000
LumaSense Technology Holdings Inc. [Member]
Business Acquisition [Line Items]
Cash paid for acquisition	$ 84,700				94,946
Less cash acquired					(10,262)
Total purchase price				$ 84,684	$ 84,684

Business Acquisitions - Assets

Business Acquisitions - Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019	Sep. 10, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Accounts and other receivable, net				$ 10,062
Inventories				13,605
Property and equipment				1,997
Goodwill				37,478
Intangible assets				45,428
Deferred income tax assets				6,937
Other assets				6,858
Total assets acquired				122,365
Accounts payable				6,520
Deferred income tax liabilities				11,699
Other liabilities				10,390
Total liabilities assumed				28,609
Total fair value of net assets acquired				93,756
Artesyn's Embedded Power Business [Member]
Business Acquisition [Line Items]
Intangible assets	$ 124
Total fair value of net assets acquired	361,253	$ 361,300
Artesyn's Embedded Power Business [Member] | Preliminary [Member]
Business Acquisition [Line Items]
Accounts and other receivable, net			$ 128,221
Inventories			140,678
Property and equipment			65,016
Operating lease right-of-use assets			60,217
Goodwill			143,262
Intangible assets			125,000
Deferred income tax assets			14,767
Other assets			61,511
Total assets acquired			738,672
Accounts payable			144,652
Operating lease liability			59,634
Pension liability			48,494
Deferred income tax liabilities			37,218
Other liabilities			80,876
Total liabilities assumed			370,874
Total fair value of net assets acquired			$ 367,798
Artesyn's Embedded Power Business [Member] | Measurement Period Adjustments [Member]
Business Acquisition [Line Items]
Inventories	(900)
Property and equipment	(1,984)
Operating lease right-of-use assets	(144)
Goodwill	(30,222)
Intangible assets	(1,000)
Deferred income tax assets	(14,767)
Other assets	2,507
Total assets acquired	(46,510)
Accounts payable	50
Operating lease liability	477
Pension liability	192
Deferred income tax liabilities	(31,372)
Other liabilities	(9,312)
Total liabilities assumed	(39,965)
Total fair value of net assets acquired	(6,545)
Artesyn's Embedded Power Business [Member] | Preliminary [Member]
Business Acquisition [Line Items]
Accounts and other receivable, net	128,221
Inventories	139,778
Property and equipment	63,032
Operating lease right-of-use assets	60,073
Goodwill	113,040
Intangible assets	124,000
Other assets	64,018
Total assets acquired	692,162
Accounts payable	144,702
Operating lease liability	60,111
Pension liability	48,686
Deferred income tax liabilities	5,846
Other liabilities	71,564
Total liabilities assumed	330,909
Total fair value of net assets acquired	361,253
Trek Holding [Member]
Business Acquisition [Line Items]
Accounts and other receivable, net				2,818
Inventories				3,941
Property and equipment				594
Intangible assets				788
Deferred income tax assets				606
Other assets				854
Total assets acquired				9,601
Accounts payable				747
Other liabilities				2,782
Total liabilities assumed				3,529
Total fair value of net assets acquired				6,072
Electrostatic Product Line [Member] [Member]
Business Acquisition [Line Items]
Accounts and other receivable, net				77
Inventories				292
Property and equipment				50
Goodwill				1,220
Intangible assets				1,400
Total assets acquired				3,039
Accounts payable				39
Total liabilities assumed				39
Total fair value of net assets acquired				3,000
LumaSense Technology Holdings Inc. [Member]
Business Acquisition [Line Items]
Accounts and other receivable, net	7,167			7,167
Inventories	9,372			9,372
Property and equipment	1,353			1,353
Goodwill	36,258			36,258
Intangible assets	43,240			43,240
Deferred income tax assets	6,331			6,331
Other assets	6,004			6,004
Total assets acquired	109,725			109,725
Accounts payable	5,734			5,734
Deferred income tax liabilities	11,699			11,699
Other liabilities	7,608			7,608
Total liabilities assumed	25,041			25,041
Total fair value of net assets acquired	84,684			84,684
LumaSense Technology Holdings Inc. [Member] | Preliminary [Member]
Business Acquisition [Line Items]
Accounts and other receivable, net				7,167
Inventories				9,372
Property and equipment				1,353
Goodwill				48,032
Intangible assets				26,000
Deferred income tax assets				8,116
Other assets				5,126
Total assets acquired				105,166
Accounts payable				5,734
Deferred income tax liabilities				7,984
Other liabilities				6,764
Total liabilities assumed				20,482
Total fair value of net assets acquired				$ 84,684
LumaSense Technology Holdings Inc. [Member] | Measurement Period Adjustments [Member]
Business Acquisition [Line Items]
Goodwill	(11,774)
Intangible assets	17,240
Deferred income tax assets	(1,785)
Other assets	878
Total assets acquired	4,559
Deferred income tax liabilities	3,715
Other liabilities	844
Total liabilities assumed	$ 4,559

Business Acquisitions - Sched_2

Business Acquisitions - Schedule of Intangible Assets Acquired, Amortization Method, and Estimated Useful Lives (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2019
Business Acquisition [Line Items]
Amortizable intangible assets:		$ 45,428
Artesyn's Embedded Power Business [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:			$ 124
Trek Holding [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:		788
Electrostatic Product Line [Member] [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:		1,400
LumaSense Technology Holdings Inc. [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:		$ 43,240	43,240
Technology Equipment [Member] | Minimum
Business Acquisition [Line Items]
Useful Life		10 years
Technology Equipment [Member] | Maximum
Business Acquisition [Line Items]
Useful Life		15 years
Technology Equipment [Member] | Artesyn's Embedded Power Business [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:			28
Useful Life	5 years
Technology Equipment [Member] | Trek Holding [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:		$ 671
Technology Equipment [Member] | Electrostatic Product Line [Member] [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:		1,200
Technology Equipment [Member] | LumaSense Technology Holdings Inc. [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:		$ 35,530
Customer Relationships [Member]
Business Acquisition [Line Items]
Useful Life		10 years
Customer Relationships [Member] | Artesyn's Embedded Power Business [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:			75
Useful Life	15 years
Customer Relationships [Member] | Trek Holding [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:		$ 117
Customer Relationships [Member] | Electrostatic Product Line [Member] [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:		200
Customer Relationships [Member] | LumaSense Technology Holdings Inc. [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:		$ 4,360
Tradename [Member]
Business Acquisition [Line Items]
Useful Life		10 years
Tradename [Member] | Artesyn's Embedded Power Business [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:			$ 21
Useful Life	10 years
Tradename [Member] | LumaSense Technology Holdings Inc. [Member]
Business Acquisition [Line Items]
Amortizable intangible assets:		$ 3,350

Business Acquisitions - Unaudit

Business Acquisitions - Unaudited Pro Forma Results (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition, Pro Forma Information [Abstract]
Sales, net	$ 338,268	$ 175,127	$ 134,810	$ 140,743	$ 154,161	$ 173,082	$ 196,032	$ 195,617	$ 788,948	$ 718,892	$ 671,012
Total sales, Pro Forma									1,202,790	1,350,037
Net income attributable to Advanced Energy Industries, Inc, As Reported	$ 10,264	$ 7,621	$ 31,686	$ 15,370	$ 19,406	$ 34,779	$ 46,361	$ 46,479	64,941	147,025	$ 137,861
Net income attributable to Advanced Energy Industries, Inc., Pro Forma									$ 83,104	$ 158,422
Earnings Per Share, Pro Forma [Abstract]
Basic earnings per share, As Reported	$ 0.27	$ 0.20	$ 0.83	$ 0.40	$ 0.51	$ 0.89	$ 1.18	$ 1.17	$ 1.70	$ 3.76	$ 3.47
Basic earnings per share, Pro Forma									2.17	4.05
Diluted earnings per share	$ 0.27	$ 0.20	$ 0.82	$ 0.40	$ 0.50	$ 0.89	$ 1.17	$ 1.16	1.69	3.74	$ 3.43
Diluted earnings per share, Pro Forma									$ 2.16	$ 4.03
Net income	$ 10,269	$ 7,631	$ 31,697	$ 15,378	$ 19,410	$ 34,786	$ 46,405	$ 46,510	$ 64,975	$ 147,111	$ 137,861
Artesyn's Embedded Power Business [Member]
Business Acquisition, Pro Forma Information [Abstract]
Sales, net									220,300
Earnings Per Share, Pro Forma [Abstract]
Net income									$ 7,100

Revenue - Nature of goods and s

Revenue - Nature of goods and services (Details) - USD ($) $ in Millions	1 Months Ended	204 Months Ended
	May 31, 2019	Dec. 31, 2035	Dec. 31, 2019	Dec. 31, 2018
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Deferred revenue transferred to buyer during sale	$ 22
Contract with Customer, Liability			$ 9.2	$ 33.4
Minimum | Scenario, Forecast [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Recognition of Deferred Revenue, Expected Annual Amount		$ 0.2
Maximum | Scenario, Forecast [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Recognition of Deferred Revenue, Expected Annual Amount		$ 1

Revenue - Sales by product line

Revenue - Sales by product line (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue from External Customer [Line Items]
Sales, net	$ 338,268	$ 175,127	$ 134,810	$ 140,743	$ 154,161	$ 173,082	$ 196,032	$ 195,617	$ 788,948	$ 718,892	$ 671,012
Semiconductor Equipment [Member]
Revenue from External Customer [Line Items]
Sales, net									403,018	533,770	554,063
Industrial And Medical [Member]
Revenue from External Customer [Line Items]
Sales, net									245,992	$ 185,122	$ 116,949
Data Center Computing [Member]
Revenue from External Customer [Line Items]
Sales, net									91,438
Telecom And Networking [Member]
Revenue from External Customer [Line Items]
Sales, net									$ 48,500

Revenue - Sales by geographic r

Revenue - Sales by geographic region (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 338,268	$ 175,127	$ 134,810	$ 140,743	$ 154,161	$ 173,082	$ 196,032	$ 195,617	$ 788,948	$ 718,892	$ 671,012
Sales to external customers									100.00%	100.00%	100.00%
North America [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									$ 373,634	$ 372,834	$ 377,347
Sales to external customers									47.40%	51.80%	56.20%
Asia [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									$ 295,155	$ 250,574	$ 221,690
Sales to external customers									37.40%	34.90%	33.10%
Europe [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									$ 119,427	$ 94,793	$ 71,796
Sales to external customers									15.10%	13.20%	10.70%
Other [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									$ 732	$ 691	$ 179
Sales to external customers									0.10%	0.10%

Revenue - Net sales by extended

Revenue - Net sales by extended warranty and service contracts (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 338,268	$ 175,127	$ 134,810	$ 140,743	$ 154,161	$ 173,082	$ 196,032	$ 195,617	$ 788,948	$ 718,892	$ 671,012
Product and service revenue recognized at point in time
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									786,918	715,055	667,440
Extended warranty and service contracts recognized over time
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									$ 2,030	$ 3,837	$ 3,572

Disposed and Discontinued Ope_3

Disposed and Discontinued Operations - Disposed Operations (Details) - USD ($)	1 Months Ended	3 Months Ended
	May 31, 2019	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of services	$ 1
Loan	2,800,000
Additional loan		$ 1,500,000
Amount available to borrow	$ 3,750,000
Loan term	10 years
Disposed operation of discount eligibility	30 days
Disposed operations recognized reduction to gain on sale	$ 2,300,000
Non-cash gain, net of tax expense, from discontinued operations	8,600,000
Continuing Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of extended warranty service obligation	22,000,000
Non cash gain from continuing operations	14,800,000
Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of reduced liabilities held in discontinued operations	10,900,000
Tax expense from discontinued operations	$ 2,400,000
Interest Rate, First Seven Years [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of interest (percent)	0.00%
Interest Rate, Thereafter [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of interest (percent)	5.00%
Discounts On First Three Years [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of early payment discounts (percent)	50.00%
Discounts On Year Four And Five [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of early payment discounts (percent)	45.00%
Discounts Thereafter [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of early payment discounts (percent)	40.00%
Grid Tied Central Solar Inverter Services Business[Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Bold Renewables Holdings, LLC [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of services	$ 1

Disposed and Discontinued Ope_4

Disposed and Discontinued Operations - Statement of Operations for Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disposed and Discontinued Operations
Cost of sales									$ (901)	$ (88)
Total operating expense									1,022	96
Operating income (loss) from discontinued operations									(121)	(8)
Other income (expense)										(24)
Other income (expense)									10,895
Income (loss) from discontinued operations before income taxes									10,774	(32)
Provision (benefit) for income taxes									2,294	6
Income (loss) from discontinued operations, net of income taxes	$ (210)	$ 375	$ 8,324	$ (9)	$ 188	$ (371)	$ 5	$ 140	$ 8,480	$ (38)	$ 1,760

Disposed and Discontinued Ope_5

Disposed and Discontinued Operations - Assets and Liabilities of Discontinued Operations (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disposed and Discontinued Operations
Cash and cash equivalents		$ 5,251	$ 7,754
Other current assets		406
Inventories	$ 30	198
Current assets of discontinued operations	30	5,855
Other assets		67
Deferred income tax assets	269	5,917
Non-current assets of discontinued operations	269	5,984
Accounts payable and other accrued expenses		350
Accrued warranty	914	4,936
Current liabilities of discontinued operations	914	5,286
Accrued warranty	698	10,429
Other liabilities	189	286
Non-current liabilities of discontinued operations	$ 887	$ 10,715

Income Taxes - Earnings Before

Income Taxes - Earnings Before Income Taxes by Geographical Area (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes
Domestic	$ (20,597)	$ 22,325	$ 29,088
Foreign	87,791	150,051	169,103
Income from continuing operations, before income taxes	$ 67,194	$ 172,376	$ 198,191

Income Taxes - Components of In

Income Taxes - Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current
Federal	$ (9,627)	$ 1,423	$ 26,550
State	882	12	601
Foreign	18,429	13,772	9,621
Total current provision	9,684	15,207	36,772
Deferred
Federal	3,822	4,021	28,297
State	(178)	2,363	(1,000)
Foreign	(2,629)	3,636	(1,979)
Total deferred provision	1,015	10,020	25,318
Total provision for income taxes	$ 10,699	$ 25,227	$ 62,090

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Effective Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes
Income taxes per federal statutory rate	$ 14,111	$ 36,199	$ 69,348
State income taxes, net of federal deduction	10	2,372	1,794
Transition tax - U.S. Tax Reform		1,174	61,690
Corporate tax rate changes - U.S. Tax Reform		(652)	11,177
Tax benefit associated with inverter business wind down			(33,837)
Stock based compensation	(97)	(974)	(5,263)
GILTI Tax	8,796	13,064
Tax effect of foreign operations	(13,086)	(19,162)	(47,482)
Uncertain tax position	(4,487)	(3,088)	4,948
Unremitted earnings	1,624	2,564
Tax credits	(6,280)	(9,844)	(658)
Change in valuation allowance	7,222	(1,306)	841
Withholding taxes	6,500	1,371
Other permanent items, net	(3,614)	3,509	(468)
Total provision for income taxes	$ 10,699	$ 25,227	$ 62,090

Income Taxes - Schedule of tax

Income Taxes - Schedule of tax expense and effective tax rate for income from continuing operations (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes
Effective federal statutory tax rate	21.00%	21.00%	21.00%	35.00%
Income from continuing operations, before income taxes		$ 67,194	$ 172,376	$ 198,191
Provision for income taxes		$ 10,699	$ 25,227	$ 62,090

Income Taxes - Schedule of Net

Income Taxes - Schedule of Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Income Taxes
Stock based compensation	$ 1,757	$ 1,337
Net operating loss and tax credit carryforwards	86,879	38,622
Interest expense limitation	7,620
Pension obligation	13,473	3,302
Excess and obsolete inventory	3,217	2,161
Deferred revenue	3,305	6,903
Employee bonuses and commissions	2,537	1,874
Depreciation and Amortization	29,015	29,525
Operating lease liabilities	23,451
Other	9,685	9,961
Deferred tax assets	180,939	93,685
Less: Valuation allowance	(76,206)	(30,924)
Net deferred tax assets	104,733	62,761
Depreciation and amortization	41,549	17,723
Unremitted earnings	4,740	3,529
Operating lease right-of-use assets	22,774
Other	2,966	1,267
Deferred tax liabilities	72,029	22,519
Net deferred tax assets	32,704	40,242
Deferred income tax assets	42,656	47,099
Deferred income tax liabilities	$ 9,952	$ 6,988

Income Taxes - Valuation Allowa

Income Taxes - Valuation Allowances (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Valuation Allowance	$ 76,206	$ 30,924
Capital loss carryforwards	40,700
Interest expense limitation carryforwards	32,900
Federal net operating loss carry forwards, have no expiration period	4,600
Increase in valuation allowance	45,300
Withdrew of permanent reinvestment assertion	123,900
Deferred tax liability related to withholding and state income taxes	2,900
Deferred Tax Liabilities, Undistributed Foreign Earnings	4,740	3,529
Domestic Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Valuation Allowance	16,000
Operating Loss Carryforwards	54,400
Tax Credit Carryforward, Amount	3,800
Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Valuation Allowance	60,200
Operating Loss Carryforwards	206,800
Income Tax Holiday, Aggregate Dollar Amount	$ 4,000	$ 17,800
Income Tax Holiday, Income Tax Benefits Per Share	$ 0.12	$ 0.47
Undistributed Earnings of Foreign Subsidiaries	$ 26,500
Deferred Tax Liabilities, Undistributed Foreign Earnings	26,500
State Taxing Authority [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	146,200
Tax Credit Carryforward, Amount	$ 1,800

Income Taxes - Reconciliation_2

Income Taxes - Reconciliation of Tax Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
Balance at beginning of period	$ 13,162	$ 15,990	$ 11,401
Additions based on tax positions taken during a prior period	484	94	1,258
Additions based on tax positions taken during the current period			4,433
Reductions based on tax positions taken during a prior period	(4,295)	(153)
Reductions related to a lapse of applicable statute of limitations	(821)	(3,144)	(1,102)
Reductions related to a settlement with taxing authorities		(382)
Balance at end of period	13,009	13,162	$ 15,990
Acquisitions [Member]
Income Tax Contingency [Line Items]
Additions based on tax positions taken during a prior period	$ 4,479	$ 757

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes
Unrecognized Tax Benefits	$ 13,009	$ 13,162	$ 15,990	$ 11,401
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	3,000	$ 1,200
Decrease in Unrecognized Tax Benefits is Reasonably Possible	$ 3,500

Earnings Per Share - Reconcilia

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								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share
Income from continuing operations	$ 10,479	$ 7,256	$ 23,373	$ 15,387	$ 19,222	$ 35,157	$ 46,400	$ 46,370	$ 56,495	$ 147,149	$ 136,101
Income from continuing operations attributable to noncontrolling interest	$ 5	$ 10	$ 11	$ 8	$ 4	$ 7	$ 44	$ 31	34	86
Income from continuing operations attributable to Advanced Energy Industries, Inc.									$ 56,461	$ 147,063	$ 136,101
Basic weighted-average common shares outstanding									38,281	39,081	39,754
Assumed exercise of dilutive stock options and restricted stock units									214	271	422
Diluted weighted-average common shares outstanding									38,495	39,352	40,176
Continuing Operations:
Basic earnings per share (in dollars per share)	$ 0.27	$ 0.19	$ 0.61	$ 0.40	$ 0.50	$ 0.90	$ 1.18	$ 1.17	$ 1.47	$ 3.76	$ 3.42
Diluted earnings per share (in dollars per share)	$ 0.27	$ 0.19	$ 0.61	$ 0.40	$ 0.50	$ 0.90	$ 1.17	$ 1.16	$ 1.47	$ 3.74	$ 3.39

Earnings Per Share - Schedule o

Earnings Per Share - Schedule of stock options and restricted units excluded in the computation of diluted earnings per share (Details) shares in Thousands	12 Months Ended
	Dec. 31, 2018shares
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

Earnings Per Share - Stock Buyb

Earnings Per Share - Stock Buyback (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 18, 2019	May 03, 2018	Sep. 16, 2015
Earnings Per Share
Authorized amount				$ 50,000		$ 150,000
Authorized program period repurchase	30 months
Authorized amount increase				$ 25,100	$ 50,000
Amount paid to repurchase shares		$ 95,125	$ 29,993
Number of shares repurchased		1,696	422
Average repurchase price per share		$ 56.07	$ 71.07

Marketable Securities (Details)

Marketable Securities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Certificates of Deposit [Member]
Marketable Securities [Line Items]
Fair value	$ 2.6	$ 2.5

Derivative Financial Instrume_3

Derivative Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Foreign currency loss from foreign currency exchange rate forward contracts		$ (750)	$ (1,438)
Derivative, notional amount			$ 16,300
Foreign Exchange Contract [Member] | Cash Flow Hedge
Derivative [Line Items]
Gain (Loss) on Foreign Currency Cash Flow Hedge	$ 3,500

Accounts and Other Receivable_2

Accounts and Other Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total receivables, net	$ 246,564	$ 100,442
Amounts billed, net
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total receivables, net	227,528	80,709
Unbilled receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total receivables, net	$ 19,036	$ 19,733

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Inventories
Parts and raw materials	$ 134,816	$ 76,647
Work in process	10,269	6,644
Finished goods	84,934	14,696
Total	$ 230,019	$ 97,987

Property and Equipment, Net - D

Property and Equipment, Net - Details of property and equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 186,255	$ 92,063
Less: Accumulated depreciation	(78,146)	(60,794)
Property and equipment, net	108,109	31,269
Buildings and Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,693	1,737
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	108,945	41,330
Computer and Communication Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	29,106	24,051
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	4,119	3,203
Vehicles [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	262	282
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	33,041	20,593
Construction in Process [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 9,089	$ 867

Property and Equipment, Net -_2

Property and Equipment, Net - Depreciation expense recorded in continuing operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property and Equipment, Net
Depreciation expense	$ 13,979	$ 7,818	$ 5,074

Goodwill - Schedule of the chan

Goodwill - Schedule of the changes in goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill and Intangible Assets
Beginning Balance	$ 101,900	$ 53,812
Measurement period adjustments to preliminary purchase price allocation	(41,996)
Additions from acquisition	143,262	49,252
Foreign currency translation	(234)	(1,164)
Ending Balance	$ 202,932	$ 101,900

Intangible Assets - Schedule of

Intangible Assets - Schedule of intangible assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 219,251	$ 77,889
Finite-Lived Intangible Assets, Accumulated Amortization	(35,240)	(22,979)
Finite-lived intangible assets, net	$ 184,011	54,910
Amortization of weighted average remaining useful life	11 years 2 months 12 days
Technology Equipment [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 83,368	39,879
Finite-Lived Intangible Assets, Accumulated Amortization	(14,250)	(7,927)
Finite-lived intangible assets, net	69,118	31,952
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	108,995	35,509
Finite-Lived Intangible Assets, Accumulated Amortization	(18,197)	(13,484)
Finite-lived intangible assets, net	90,798	22,025
Trademarks and other [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	26,888	2,501
Finite-Lived Intangible Assets, Accumulated Amortization	(2,793)	(1,568)
Finite-lived intangible assets, net	$ 24,095	$ 933

Intangible Assets - Schedule _2

Intangible Assets - Schedule of amortization expense relating to intangible assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill and Intangible Assets
Amortization expense	$ 12,168	$ 5,774	$ 4,350

Intangible Assets - Schedule _3

Intangible Assets - Schedule of Finite-Lived Intangible Assets, Future Amortization Expense (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Goodwill and Intangible Assets
2020	$ 20,109
2021	20,009
2022	19,745
2023	19,727
2024	16,888
Thereafter	87,533
Finite-lived intangible assets, net	$ 184,011	$ 54,910

Restructuring Costs (Details)

Restructuring Costs (Details) - USD ($) $ in Thousands	3 Months Ended						12 Months Ended		24 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring expense	$ 1,418	$ 152	$ 1,795	$ 1,673	$ 3,836	$ 403	$ 5,038	$ 4,239	$ 9,277
Severance and related charges
Restructuring Cost and Reserve [Line Items]
Restructuring expense							3,041	$ 4,239	7,280
Facility relocation and closure charges
Restructuring Cost and Reserve [Line Items]
Restructuring expense							$ 1,996		$ 1,996

Restructuring Costs - Schedule

Restructuring Costs - Schedule of Restructuring liabilities (Details) - USD ($) $ in Thousands	3 Months Ended						12 Months Ended		24 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019
Restructuring Reserve [Roll Forward]
Beginning balance				$ 3,806			$ 3,806
Cost incurred and charged to expense	$ 1,418	$ 152	$ 1,795	$ 1,673	$ 3,836	$ 403	5,038	$ 4,239	$ 9,277
Cost paid or otherwise settled							(6,673)
Effect of change in exchange rates							1
Ending balance	$ 2,172				$ 3,806		2,172	3,806	2,172
Severance and related charges
Restructuring Reserve [Roll Forward]
Cost incurred and charged to expense							3,041	$ 4,239	7,280
Facility relocation and closure charges
Restructuring Reserve [Roll Forward]
Cost incurred and charged to expense							$ 1,996		$ 1,996

Warranties - Changes in accrued

Warranties - Changes in accrued product warranties (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Movement in Standard Product Warranty Accrual [Roll Forward]
Balances at beginning of period	$ 2,084	$ 2,312	$ 2,329
Warranty acquired in business combinations	4,818	305	118
Increases to accruals	1,752	1,606	2,029
Warranty expenditures	(2,249)	(2,127)	(2,184)
Effect of changes in exchange rates	8	(12)	20
Balances at end of period	$ 6,413	$ 2,084	$ 2,312

Warranties - Narrative (Details

Warranties - Narrative (Details)	12 Months Ended
	Dec. 31, 2019
Minimum
Product Liability Contingency [Line Items]
Standard Product Warranty Term	12 months
Maximum
Product Liability Contingency [Line Items]
Standard Product Warranty Term	24 months

Leases - Components of operatin

Leases - Components of operating lease expense (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Leases
Operating lease cost	$ 11,052
Short-term and variable lease cost	4,726
Total operating lease costs	$ 15,778

Leases - Operating lease maturi

Leases - Operating lease maturity schedule (Details) $ in Thousands	Dec. 31, 2019USD ($)
Leases
2020	$ 22,351
2021	19,771
2022	13,503
2023	10,786
2024	9,601
Thereafter	56,355
Total lease payments	132,367
Less: Interest	(23,517)
Present value of lease liabilities	$ 108,850

Leases - Other lease cost infor

Leases - Other lease cost information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Lessee, Lease, Description [Line Items]
Term of contract	16 years
Right of use assets	$ 21,800
Lease liability	$ 21,800
Weighted Average Remaining Lease Term	7 years 6 months
Weighted Average Discount Rate	4.05%
Cash paid for operating leases	$ 12,101
Right-of-use assets obtained in exchange for operating lease liabilities	84,551
Artesyn's Embedded Power Business [Member]
Lessee, Lease, Description [Line Items]
Right-of-use assets obtained in exchange for operating lease liabilities	$ 60,100

Leases - Future minimum lease p

Leases - Future minimum lease payments under operating leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Future minimum lease payments under operating leases were:
2019		$ 9,093
2020		7,561
2021		6,938
2022		3,862
2023		3,448
Thereafter		18,349
Total lease payments		49,251
Rent expense for operating leases	$ 7,400	$ 6,500

Employee Retirement Plans and_3

Employee Retirement Plans and Postretirement Benefits - Defined Contribution Plan (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Employee Retirement Plans and Postretirement Benefits
Defined Contribution Plan, vesting period	4 years
Matching contributions	50.00%
Employer Matching Contribution, Percent of Employees' Gross Pay	6.00%
Defined Contribution Plan, Cost	$ 1.6	$ 1.4	$ 1.1

Employee Retirement Plans and_4

Employee Retirement Plans and Postretirement Benefits - Projected Benefit Obligation and Plan Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Changes in projected benefit obligation
Projected benefit obligation, beginning of year	$ 33,178	$ 34,498
Acquisition	48,350	1,063
Service cost	272	841
Interest cost	1,211	802	$ 809
Actuarial loss	(193)	(988)
Benefits paid	(1,779)	(1,113)
Translation adjustment	2,223	(1,925)
Projected benefit obligation, end of year	83,262	33,178	34,498
Changes in fair value of plan assets
Fair value of plan assets, beginning of year	13,433	14,181
Acquisitions	102	981
Actual return on plan assets	380	675
Contributions	644	828
Benefits paid	(1,176)	(1,086)
Actuarial gain	1,064	(1,357)
Translation adjustment	456	(789)
Fair value of plan assets, end of year	14,903	13,433	$ 14,181
Funded status of plan	$ (68,359)	$ (19,745)

Employee Retirement Plans and_5

Employee Retirement Plans and Postretirement Benefits - Net periodic pension benefit cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net periodic pension benefit cost
Service cost	$ 272	$ 841
Interest cost	1,211	802	$ 809
Expected return on plan assets	(615)	(665)	(597)
Amortization of actuarial gain and losses	411	478	503
Net periodic pension cost	$ 1,279	$ 1,456	$ 715

Employee Retirement Plans and_6

Employee Retirement Plans and Postretirement Benefits - Net Periodic Pension Cost Assumptions (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assumptions used in the determination of the net periodic pension cost:
Discount rate	2.70%	2.80%	2.60%
Expected long-term return on plan assets	4.60%	4.80%	4.80%

Employee Retirement Plans and_7

Employee Retirement Plans and Postretirement Benefits - Fair Value of Plan Assets by Category (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	$ 14,903	$ 13,433	$ 14,181
Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	13,704	13,308
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	1,045	72
Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	154	53
Multi-asset Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	$ 4,825	4,570
Investment percentage within Plan Asset category	32.40%
Multi-asset Fund [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	$ 4,825	4,570
Defined Growth Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	$ 4,855	4,650
Investment percentage within Plan Asset category	32.60%
Defined Growth Fund [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	$ 4,855	4,650
Index-Linked Gilts [Member]
Defined Benefit Plan Disclosure [Line Items]
Investment percentage within Plan Asset category	13.00%
Index-Linked Gilts [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	$ 1,934	2,044
Index-Linked Gilts [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	1,934	2,044
Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	$ 2,090	2,044
Investment percentage within Plan Asset category	14.00%
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	$ 2,090	2,044
Insurance Contract [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	$ 1,045	72
Investment percentage within Plan Asset category	7.00%
Insurance Contract [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	$ 1,045	72
Defined Benefit Plan, Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	154	53
Defined Benefit Plan, Cash [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of Plan Assets	$ 154	$ 53

Employee Retirement Plans and_8

Employee Retirement Plans and Postretirement Benefits - Expected Future Benefit Payments (Details) $ in Thousands	Dec. 31, 2019USD ($)
Expected Future Benefit Payments
2020	$ 6,113
2021	7,039
2022	5,673
2023	5,716
2024	14,487
Thereafter	$ 134,802

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details)	12 Months Ended
	Dec. 31, 2019USD ($)plan$ / sharesshares	Dec. 31, 2018USD ($)$ / shares	Dec. 31, 2017USD ($)$ / shares	Dec. 31, 2016	May 04, 2017shares	May 01, 2010shares	Apr. 30, 2010shares
Stock-based incentive compensation plans | plan	2
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Reserved | shares	3,300,000				5,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | shares	2,500,000
Estimated Forfeiture rates for Share Based Compensation	10.00%	10.00%	17.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value	$ 1,600,000	$ 4,100,000	$ 9,700,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 9,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	4 years 1 month 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms	1 year 3 months 18 days
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term				4 years 3 months 18 days
Share based Compensation Arrangement By Share based Payment Award Options Contractual Term	10 years
Stock-based compensation expense	$ 7,327,000	$ 9,703,000	$ 12,549,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate				43.00%
2017 OMNIBUS Incentive Plan [Member] [Domain]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | shares	2,300,000
Restricted Stock Units (RSUs) [Member]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 5,900,000
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	6 months	6 months	6 months
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate	41.30%	38.00%	33.30%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.00%	0.00%	0.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			1.10%
Vesting period	3 years
Minimum | Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	1.62%	2.10%	1.07%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			1.40%
Vesting period	4 years
Maximum | Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	2.31%	2.56%	1.45%
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value	$ 8,300,000	$ 13,600,000	$ 14,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares	$ 52.24	$ 64.48	$ 63.63
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | shares	1,000,000					1,000,000	500,000
Share-based Compensation Arrangement By Share-based Payment Award, Employee Contribution, Amount	$ 5,000
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date	85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Purchase Date	85.00%
Employee Stock [Member] | Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | shares	200,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 200,000
Employee Service Share-based Compensation recognized remaining period	5 months
Stock-based compensation expense	$ 500,000	$ 400,000	$ 200,000
Employee Stock [Member] | Maximum
Share-based Compensation Arrangement By Share-based Payment Award, Employee Contribution, Percent	15.00%

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of stock-based compensation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock-Based Compensations
Stock-based compensation expense	$ 7,327	$ 9,703	$ 12,549

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value Assumptions by Grant Year (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Estimated Forfeiture rates for Share Based Compensation	10.00%	10.00%	17.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term				4 years 3 months 18 days
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate				43.00%
Stock-based compensation expense	$ 7,327	$ 9,703	$ 12,549
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.00%	0.00%	0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	6 months	6 months	6 months
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate	41.30%	38.00%	33.30%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			1.10%
Minimum | Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	1.62%	2.10%	1.07%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			1.40%
Maximum | Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	2.31%	2.56%	1.45%

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule of Weighted Average Fair Value and Intrinsic Value (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock-Based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value	$ 1.6	$ 4.1	$ 9.7

Stock-Based Compensation - Chan

Stock-Based Compensation - Changes in Outstanding Stock Options (Details) - Time Based [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 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, Beginning Balance	230	317	474
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	(42)	(83)	(152)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	0	0	(2)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period	(3)	(4)	(3)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance	185	230	317
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Beginning Balance	$ 20.73	$ 18.97	$ 17.47
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	17.73	14.41	14.32
Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price	0	0	26.32
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	9.91	11.97	11.09
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Ending Balance	$ 21.56	$ 20.73	$ 18.97
Options Vested During the Year	$ 0	$ 2	$ 9

Stock-Based Compensation - Sc_3

Stock-Based Compensation - Schedule of Stock Options by Exercise Price (Details) shares in Thousands	12 Months Ended
	Dec. 31, 2019$ / sharesshares
9.51 - 13.85 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options | shares	23
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	1 year 5 months 1 day
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 12
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | shares	23
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 12
14.21 - 16.25 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options | shares	20
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	8 months 19 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 15.06
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | shares	20
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 15.06
18.77 - 18.77 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options | shares	43
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	4 years 9 months
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 18.77
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | shares	43
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 18.77
26.32 - 26.32 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options | shares	99
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	5 years 1 month 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 26.32
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | shares	99
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 26.32
9.51 - 26.32 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options | shares	185
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	4 years 1 month 2 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 21.56
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | shares	185
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 21.56
Minimum | 9.51 - 13.85 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price, Beginning Balance	9.51
Minimum | 14.21 - 16.25 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price, Beginning Balance	14.21
Minimum | 18.77 - 18.77 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price, Beginning Balance	18.77
Minimum | 26.32 - 26.32 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price, Beginning Balance	26.32
Minimum | 9.51 - 26.32 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price, Beginning Balance	9.51
Maximum | 9.51 - 13.85 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price, Beginning Balance	13.85
Maximum | 14.21 - 16.25 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price, Beginning Balance	16.25
Maximum | 18.77 - 18.77 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price, Beginning Balance	18.77
Maximum | 26.32 - 26.32 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price, Beginning Balance	26.32
Maximum | 9.51 - 26.32 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price, Beginning Balance	$ 26.32

Stock-Based Compensation - Ch_2

Stock-Based Compensation - Changes in RSU (Details) - Restricted Stock Units (RSUs) [Member] - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	534	352	386	354
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 56.56	$ 58.17	$ 51.06	$ 29.60
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	380	245	252
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(155)	(207)	(211)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	$ 50.95	$ 54.94	$ 30.62
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(43)	(72)	(9)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 51.82	$ 50.79	$ 33.91
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 52.24	$ 64.48	$ 63.63

Stock-Based Compensation - Sc_4

Stock-Based Compensation - Schedule of Weighted Average Fair Value and Intrinsic Value for RSUs (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value	$ 1.6	$ 4.1	$ 9.7
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 56.56	$ 58.17	$ 51.06	$ 29.60
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value	$ 8.3	$ 13.6	$ 14.8

Related Party Transactions (Det

Related Party Transactions (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)company	Dec. 31, 2018USD ($)company	Dec. 31, 2017USD ($)company
Related Party Transactions
Sales to related parties | $	$ 1,340	$ 1,028	$ 1,425
Number of related party customers | company	1	1	1

Related Party Transactions - Sc

Related Party Transactions - Schedule of related party transactions (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019company	Dec. 31, 2018USD ($)company	Dec. 31, 2017company
Related Party Transactions
Accounts receivable from related parties | $		$ 109
Number of related party customers | company	1	1	1

Geographic and Significant Cu_3

Geographic and Significant Customer Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue, Major Customer [Line Items]
Sales, net	$ 338,268	$ 175,127	$ 134,810	$ 140,743	$ 154,161	$ 173,082	$ 196,032	$ 195,617	$ 788,948	$ 718,892	$ 671,012
Product [Member]
Revenue, Major Customer [Line Items]
Sales, net									678,061	610,326	$ 578,650
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Applied Materials, Inc. [Member]
Revenue, Major Customer [Line Items]
Sales, net									$ 164,724	$ 258,027
Concentration Risk, Percentage									20.90%	35.90%
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Lam Research [Member]
Revenue, Major Customer [Line Items]
Sales, net									$ 88,251	$ 109,005
Concentration Risk, Percentage									11.20%	15.20%
Accounts Receivable [Member] | Applied Materials, Inc. [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage									14.90%	34.20%
Accounts receivable	36,849				34,301				$ 36,849	$ 34,301
Accounts Receivable [Member] | Nidec Motor Corporation [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage									15.40%
Accounts receivable	$ 38,071								$ 38,071
Accounts Receivable [Member] | Lam Research [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage										12.10%
Accounts receivable					$ 12,181					$ 12,181

Geographic and Significant Cu_4

Geographic and Significant Customer Information - Schedule of Long-lived Assets by Geographic Region (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Long-Lived Assets	$ 600,456	$ 188,079
United States [Member]
Segment Reporting Information [Line Items]
Long-Lived Assets	239,511	115,869
Asia [Member]
Segment Reporting Information [Line Items]
Long-Lived Assets	301,020	12,274
Europe [Member]
Segment Reporting Information [Line Items]
Long-Lived Assets	$ 59,925	$ 59,936

Credit Facility (Details)

Credit Facility (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019
Line of Credit Facility [Line Items]
Carrying value of outstanding debt	$ 341,250
Long-term debt	$ 339,027
Revolving Facility [Member]
Line of Credit Facility [Line Items]
Line of credit facility, borrowing capacity		$ 500,000
Unused line fee payment percentage	0.10%
Credit availability under the Loan Agreement	$ 150,000
Revolving Facility [Member] | Bank of America N.A. [Member]
Line of Credit Facility [Line Items]
Line of credit facility, current borrowing capacity	150,000
Term Loan Facility [Member]
Line of Credit Facility [Line Items]
Line of credit facility, borrowing capacity		350,000
Carrying value of outstanding debt	$ 341,250
Unsecured Revolving Facility [Member]
Line of Credit Facility [Line Items]
Line of credit facility, borrowing capacity		$ 150,000
Revolving Credit Facility and Term Loan Facility
Line of Credit Facility [Line Items]
Effective rate percentage	2.55%

Credit Facility - Debt obligati

Credit Facility - Debt obligation (Details) $ in Thousands	Dec. 31, 2019USD ($)
Debt:
Carrying value of outstanding debt	$ 341,250
Less: debt issuance costs	(2,223)
Total debt	339,027
Less current portion of debt	(17,500)
Total long-term debt	321,527
Term Loan Facility [Member]
Debt:
Carrying value of outstanding debt	$ 341,250

Credit Facility - Contractual m

Credit Facility - Contractual maturities (Details) $ in Thousands	Dec. 31, 2019USD ($)
Credit Facility
2020	$ 17,500
2021	17,500
2022	17,500
2023	17,500
2024	271,250
Total	$ 341,250

Credit Facility - Interest expe

Credit Facility - Interest expense and unused line of credit fees (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Credit Facility
Interest expense	$ 2,994
Amortization of debt issuance costs	186
Unused line of credit fees	236	$ 228	$ 66
Total interest expense	$ 3,416	$ 228	$ 66

Supplemental Quarterly Financ_3

Supplemental Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended			24 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019
Supplemental Quarterly Financial Data
Sales, net	$ 338,268	$ 175,127	$ 134,810	$ 140,743	$ 154,161	$ 173,082	$ 196,032	$ 195,617	$ 788,948	$ 718,892	$ 671,012
Gross profit	112,295	73,491	64,126	65,740	75,188	85,539	101,235	103,645	315,652	365,607	356,381
Restructuring expense	1,418	152	1,795	1,673	3,836	403			5,038	4,239		$ 9,277
Operating income	22,202	9,390	11,005	11,791	19,570	39,862	56,018	56,103	54,388	171,553	200,770
Income (loss) from continuing operations, net of income taxes	10,479	7,256	23,373	15,387	19,222	35,157	46,400	46,370	56,495	147,149	136,101
Income (loss) from discontinued operations, net of income taxes	(210)	375	8,324	(9)	188	(371)	5	140	8,480	(38)	1,760
Net income	10,269	7,631	31,697	15,378	19,410	34,786	46,405	46,510	64,975	147,111	137,861
Income from continuing operations attributable to noncontrolling interest	5	10	11	8	4	7	44	31	34	86
Net income attributable to Advanced Energy Industries, Inc.	$ 10,264	$ 7,621	$ 31,686	$ 15,370	$ 19,406	$ 34,779	$ 46,361	$ 46,479	$ 64,941	$ 147,025	$ 137,861
Continuing operations: Basic earnings per share	$ 0.27	$ 0.19	$ 0.61	$ 0.40	$ 0.50	$ 0.90	$ 1.18	$ 1.17	$ 1.47	$ 3.76	$ 3.42
Continuing operations: Diluted earnings per share	0.27	0.19	0.61	0.40	0.50	0.90	1.17	1.16	1.47	3.74	3.39
Discontinued operations: Basic earnings per share	(0.01)	0.01	0.22			(0.01)			0.22		0.04
Discontinued operations: Diluted earnings per share	(0.01)	0.01	0.22			(0.01)			0.22		0.04
Basic earnings per share	0.27	0.20	0.83	0.40	0.51	0.89	1.18	1.17	1.70	3.76	3.47
Diluted earnings per share	$ 0.27	$ 0.20	$ 0.82	$ 0.40	$ 0.50	$ 0.89	$ 1.17	$ 1.16	$ 1.69	$ 3.74	$ 3.43