ChampionX (CHX) 10-Q 19 Nov 19 2019 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2019	Nov. 15, 2019
Document and Entity Information [Abstract]
Document Type	10-Q
DocumentQuarterlyReport	true
Document Period End Date	Sep. 30, 2019
DocumentTransitionReport	false
Entity File Number	001-38441
Entity Registrant Name	Apergy Corporation
Entity Incorporation, State Country Name	DE
Entity Tax Identification Number	823066826
Entity Central Index Key	0001723089
Entity Address, Address Line One	2445 Technology Forest Blvd.
Entity Address, Address Line Two	Building 4, 12th Floor
Entity Address, City or Town	The Woodlands
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77381
City Area Code	281
Local Phone Number	403-5772
Security 12b Title	Common Stock, $0.01 Par Value
Trading Symbol	APY
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		77,459,846
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Amendment Flag	false

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (unaudited) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended						9 Months Ended
		Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Total revenue		$ 278,381			$ 316,468			$ 886,126	$ 905,444
Cost of goods and services		186,862			202,734			579,289	594,416
Gross profit		91,519			113,734			306,837	311,028
Selling, general and administrative expense		68,813			69,206			200,790	194,374
Interest expense, net		9,537			10,584			30,068	16,813
Other (income) expense, net		(309)			725			3,469	3,917
Income before income taxes		13,478			33,219			72,510	95,924
Provision for income taxes		3,059			7,723			15,672	24,159
Net income		10,419	$ 23,850	$ 22,569	25,496	$ 22,075	$ 24,194	56,838	71,765
Net income attributable to noncontrolling interest		194			232			547	295
Net income attributable to Apergy		$ 10,225			$ 25,264			$ 56,291	$ 71,470
Earnings per share, basic	[1]	$ 0.13			$ 0.33			$ 0.73	$ 0.92
Earnings per share, diluted	[1]	$ 0.13			$ 0.33			$ 0.73	$ 0.92
Weighted-average number of shares outstanding, basic	[1]	77,460			77,340			77,416	77,340
Weighted-average number of shares outstanding, diluted	[1]	77,573			77,569			77,615	77,742
Product revenue
Revenue		$ 244,651			$ 283,102			$ 787,698	$ 807,949
Other revenue
Revenue		$ 33,730			$ 33,366			$ 98,428	$ 97,495
[1]	See Note 4—Earnings Per Share

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Net income		$ 10,419	$ 25,496	$ 56,838	$ 71,765
Foreign currency translation adjustments [Abstract]
Foreign currency translation adjustments (1)	[1]	(2,900)	(515)	(836)	(9,080)
Pension and other post-retirement benefit plans [Abstract]
Net actuarial gain (loss) arising during period		0	0	(323)	170
Reclassification adjustment for net actuarial loss included in net income		68	86	203	181
Reclassification adjustment for settlement losses included in net income		0	353	355	353
Total pension and other post-retirement benefit plans (2)	[2]	68	439	235	704
Other comprehensive loss		(2,832)	(76)	(601)	(8,376)
Comprehensive income		7,587	25,420	56,237	63,389
Comprehensive income attributable to noncontrolling interest		194	232	547	295
Comprehensive income attributable to Apergy		$ 7,393	$ 25,188	$ 55,690	$ 63,094
[1]	Net of income tax (expense) benefit of nil for the three and nine months ended September 30, 2019 and 2018.
[2]	Net of income tax (expense) benefit of $23 and $161 for the three months ended September 30, 2019 and 2018, respectively, and $202 and $123 for the nine months ended September 30, 2019 and 2018, respectively.

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) (Parentheticals) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income (Paranthetical) [Abstract]
Foreign currency translation adjustments, tax	$ 0	$ 0	$ 0	$ 0
Pension and other post-retirement benefit plans, tax	$ 23	$ 161	$ 202	$ 123

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Assets
Cash and cash equivalents	$ 40,627	$ 41,832
Receivables, net of allowances of $3,987 in 2019 and $5,178 in 2018	236,381	249,948
Inventories, net	219,614	218,319
Prepaid expenses and other current assets	34,516	20,211
Total current assets	531,138	530,310
Property, plant and equipment, net of accumulated depreciation of $420,113 in 2019 and $392,344 in 2018	249,385	244,328
Goodwill	910,693	904,985
Intangible assets, net of accumulated amortization of $407,724 in 2019 and $380,960 in 2018	251,411	283,688
Other non-current assets	29,626	8,445
Total assets	1,972,253	1,971,756
Liabilities and Equity
Accounts payable	114,185	131,058
Accrued compensation and employee benefits	40,416	40,546
Accrued expenses and other current liabilities	51,852	30,391
Total current liabilities	206,453	201,995
Long-term debt	588,580	666,108
Deferred income taxes	97,588	101,724
Other long-term liabilities	37,826	20,402
Total liabilities	930,447	990,229
Stockholders' equity:
Common stock (2.5 billion shares authorized, $0.01 par value) 77.5 million shares and 77.4 million shares issued and outstanding in 2019 and 2018, respectively	775	774
Capital in excess of par value of common stock	971,075	965,372
Retained earnings	110,458	55,829
Accumulated other comprehensive loss	(43,507)	(42,906)
Total stockholders’ equity	1,038,801	979,069
Noncontrolling interest	3,005	2,458
Total equity	1,041,806	981,527
Total liabilities and equity	$ 1,972,253	$ 1,971,756

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Allowance for doubtful accounts receivable	$ 3,987	$ 5,178
Accumulated depreciation on property, plant, and equipment	420,113	392,344
Intangible assets, accumulated amortization	$ 407,724	$ 380,960
Par value of common stock (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	2,500,000,000	2,500,000,000
Common stock, shares issued (in shares)	77,500,000	77,400,000
Common stock, shares outstanding (in shares)	77,500,000	77,400,000

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (unaudited) - USD ($) $ in Thousands	Total	Common Stock, Par Value	Common Stock, Capital in excess of par value	Retained Earnings	Net Parent Investment in Apergy	Accum. Other Comp. Loss	Non-controlling Interest
Balance at Dec. 31, 2017	$ 1,640,385				$ 1,662,052	$ (26,416)	$ 4,749
Net income	24,194				24,052		142
Other comprehensive income (loss)	(1,642)					(1,642)
Net transfer to Dover	(1,635)				(1,635)
Balance at Mar. 31, 2018	1,661,302				1,685,784	(29,373)	4,891
Balance at Dec. 31, 2017	1,640,385				1,662,052	(26,416)	4,749
Net income	71,765
Other comprehensive income (loss)	(8,376)
Balance at Sep. 30, 2018	964,762	$ 773	$ 967,044	$ 33,258	0	(38,527)	2,214
Balance at Mar. 31, 2018	1,661,302				1,685,784	(29,373)	4,891
Net income	22,075			7,994	14,160		(79)
Other comprehensive income (loss)	(6,658)					(6,658)
Net transfer to Dover	(739,284)				(737,834)	(1,450)
Reclassification of Net Parent Investment	0		962,110		(962,110)
Stock Issued During Period, Value, New Issues	0	773	(773)
Stock-based compensation	851		851
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(2,720)						(2,720)
Other	(39)						(39)
Balance at Jun. 30, 2018	935,527	773	962,188	7,994	0	(37,481)	2,053
Net income	25,496			25,264			232
Other comprehensive income (loss)	(76)					(76)
Net transfer to Dover	2,118				3,088	(970)
Reclassification of Net Parent Investment	0		3,088		(3,088)
Stock-based compensation	1,768		1,768
Other	(71)						(71)
Balance at Sep. 30, 2018	964,762	773	967,044	33,258	0	(38,527)	2,214
Balance at Dec. 31, 2018	981,527	774	965,372	55,829	0	(42,906)	2,458
Net income	22,569			22,287			282
Other comprehensive income (loss)	1,189					1,189
Stock-based compensation	2,285		2,285
Taxes withheld on issuance of stock-based awards	(719)		(719)
Other	14						14
Balance at Mar. 31, 2019	1,005,203	774	966,938	76,454	0	(41,717)	2,754
Balance at Dec. 31, 2018	981,527	774	965,372	55,829	0	(42,906)	2,458
Net income	56,838
Other comprehensive income (loss)	(601)
Balance at Sep. 30, 2019	1,041,806	775	971,075	110,458	0	(43,507)	3,005
Balance at Mar. 31, 2019	1,005,203	774	966,938	76,454	0	(41,717)	2,754
Net income	23,850			23,779			71
Other comprehensive income (loss)	1,042					1,042
Stock-based compensation	2,736	1	2,735
Taxes withheld on issuance of stock-based awards	(1,080)		(1,080)
Other	(14)						(14)
Balance at Jun. 30, 2019	1,031,737	775	968,593	100,233	0	(40,675)	2,811
Net income	10,419			10,225			194
Other comprehensive income (loss)	(2,832)					(2,832)
Stock-based compensation	2,524		2,524
Taxes withheld on issuance of stock-based awards	(42)		(42)
Balance at Sep. 30, 2019	$ 1,041,806	$ 775	$ 971,075	$ 110,458	$ 0	$ (43,507)	$ 3,005

CONDENSED CONSOLIDATED STATEM_5

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash provided (required) by operating activities:
Net income	$ 56,838	$ 71,765
Adjustments to reconcile net income to net cash provided (required) by operating activities:
Depreciation	51,116	52,814
Amortization	38,504	38,863
Stock-based compensation	7,545	3,129
Impairment	1,849	0
Loss on sale of business	(2,475)	0
Deferred income taxes	(3,717)	(4,674)
Employee benefit plan expense	1,506	3,012
Other	517	6,286
Changes in operating assets and liabilities (net of effects of foreign exchange):
Receivables	12,218	(79,533)
Inventories	11,455	(21,149)
Prepaid expenses and other current assets	(16,742)	(4,640)
Accounts payable	(15,532)	27,776
Accrued compensation and employee benefits	(3,651)	10,628
Accrued expenses and other liabilities	14,288	23,709
Leased assets	34,645	33,331
Other	(634)	(1,624)
Net cash provided by operating activities	123,390	93,031
Cash provided (required) by investing activities:
Capital expenditures	(31,589)	(42,883)
Proceeds from sale of fixed assets	2,954	970
Payment on sale of business	(2,194)	0
Payment on acquisition	(12,500)	0
Purchase price adjustments on acquisition	0	53
Net cash required by investing activities	(43,329)	(41,860)
Cash provided (required) by financing activities:
Proceeds from long-term debt, net of discounts	36,500	713,963
Payment of debt issuance costs	0	(16,006)
Repayment of long-term debt	(111,500)	(20,000)
Distributions to Dover Corporation, net	0	(728,857)
Distribution to noncontrolling interest	0	(2,720)
Payment of finance lease obligations	(4,108)	(3,174)
Payments related to taxes withheld on stock-based compensation	(1,841)	0
Net cash required by financing activities	(80,949)	(56,794)
Effect of exchange rate changes on cash and cash equivalents	(317)	(75)
Net decrease in cash and cash equivalents	(1,205)	(5,698)
Cash and cash equivalents at beginning of period	41,832	23,712
Cash and cash equivalents at end of period	$ 40,627	$ 18,014

Basis of Presentation and Separ

Basis of Presentation and Separation	9 Months Ended
	Sep. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Separation	BASIS OF PRESENTATION AND SEPARATION Apergy Corporation (“Apergy”) is a leading provider of highly engineered equipment and technologies that help companies drill for and produce oil and gas safely and efficiently around the world. Our products provide efficient functioning throughout the lifecycle of a well—from drilling to completion to production. We report our results of operations in the following reporting segments: Production & Automation Technologies and Drilling Technologies. Our Production & Automation Technologies segment offerings consist of artificial lift equipment and solutions, including rod pumping systems, electric submersible pump systems, progressive cavity pumps and drive systems and plunger lifts, as well as a full automation and digital offerings consisting of equipment, software and Industrial Internet of Things solutions for downhole monitoring, wellsite productivity enhancement and asset integrity management. Our Drilling Technologies segment offerings provide market leading polycrystalline diamond cutters and bearings that result in cost effective and efficient drilling. Separation and Distribution On April 18, 2018, Dover Corporation’s (“Dover”) Board of Directors approved the separation of entities conducting its oil and gas energy business within Dover’s Energy segment (the “Separation”) into an independent, publicly traded company named Apergy Corporation. In accordance with the separation and distribution agreement, the two companies were separated by Dover distributing to Dover’s stockholders all 77,339,828 shares of common stock of Apergy on May 9, 2018. Each Dover shareholder received one share of Apergy stock for every two shares of Dover stock held at the close of business on the record date of April 30, 2018. Following the Separation, Dover retained no ownership interest in Apergy, and each company, as of May 9, 2018, has separate public ownership, boards of directors and management. Basis of Presentation Prior to the Separation, our results of operations, financial position and cash flows were derived from the consolidated financial statements and accounting records of Dover and reflect the combined historical results of operations, financial position and cash flows of certain Dover entities conducting its upstream oil and gas energy business within Dover’s Energy segment, including an allocated portion of Dover’s corporate costs. These financial statements have been presented as if such businesses had been combined for all periods prior to the Separation. All intercompany transactions and accounts within Dover were eliminated. The assets and liabilities were reflected on a historical cost basis since all of the assets and liabilities presented were wholly owned by Dover and were transferred within the Dover consolidated group. The statements of income also include expense allocations for certain corporate functions historically performed by Dover and not allocated to its operating segments, including corporate executive management, human resources, information technology, facilities, tax, shared services, finance and legal, including the costs of salaries, benefits and other related costs. These expense allocations were based on direct usage or benefit where identifiable, with the remainder allocated on the basis of revenue, headcount or other measures. These pre-Separation combined financial statements may not include all of the actual expenses that would have been incurred had we been a stand-alone public company during the periods presented prior to the Separation and consequently may not reflect our results of operations, financial position and cash flows had we been a stand-alone public company during the periods presented prior to the Separation. Actual costs that would have been incurred if we had been a stand-alone public company would depend on a variety of factors, including organizational structure and strategic decisions made in various areas, including information technology and infrastructure. Prior to the Separation, transactions between Apergy and Dover, with the exception of transactions discussed in Note 3— Related Party Transactions , are reflected in the condensed consolidated statements of cash flows as a financing activity in “Distributions to Dover Corporation, net.” Intercompany notes payable to Dover prior to the Separation were not settled in cash. Accordingly, no interest expense related to intercompany debt was presented in the condensed consolidated statements of income for the period presented prior to the Separation. See Note 3—Related Party Transactions for additional information. All financial information presented after the Separation represents the consolidated results of operations, financial position and cash flows of Apergy. Accordingly, our results of operations and cash flows consist of the consolidated results of Apergy during the periods ended September 30, 2019 and for the period from May 9, 2018 to September 30, 2018, and the combined results of operations and cash flows for the periods prior to May 9, 2018. Our balance sheets as of September 30, 2019 and December 31, 2018, reflect the consolidated balances of Apergy. Our management believes the assumptions underlying these condensed consolidated financial statements, including the assumptions regarding the allocation of corporate expenses from Dover for periods prior to the Separation, are reasonable. The legal transfer of the oil and gas energy businesses from Dover to Apergy occurred on May 9, 2018; however, for ease of reference, and unless otherwise stated or the context otherwise requires, all references to “Apergy Corporation,” “Apergy,” “we,” “us” or “our” refer (i) prior to the Separation, to the Apergy businesses, consisting of entities, assets and liabilities conducting the oil and gas business within Dover’s Energy segment and (ii) after the Separation, to Apergy Corporation and its consolidated subsidiaries. Interim Financial Information The accompanying unaudited condensed consolidated financial statements of Apergy have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission pertaining to interim financial information. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP have been condensed or omitted. Therefore, these financial statements should be read in conjunction with the audited consolidated financial statements, and notes thereto, which are included in our Annual Report on Form 10-K for the year ended December 31, 2018. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Although these estimates are based on management’s best knowledge of current events and actions that we may undertake in the future, actual results may differ from our estimates. In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments (consisting of normal recurring adjustments unless otherwise specified) necessary for a fair statement of our financial condition and results of operations as of and for the periods presented. Revenue, expenses, assets and liabilities can vary during each quarter of the year. Therefore, the results and trends in these financial statements may not be representative of the results that may be expected for the year ending December 31, 2019. Change in Accounting Estimate Effective January 1, 2019, we changed our estimate of the useful lives for certain equipment used within our leased asset program in our Production & Automation Technologies segment to better reflect the estimated periods in which the assets will remain in service. The estimated useful lives of the equipment, previously estimated at three years, was increased to five years. The effect of this change in estimate for the three months ended September 30, 2019 , was a reduction in depreciation expense of $2.5 million , an increase in net income of $1.9 million , and an increase in basic and diluted earnings per share of $0.02 per share. The effect of this change in estimate for the nine months ended September 30, 2019 , was a reduction in depreciation expense of $6.5 million , an increase in net income of $4.9 million , and an increase in basic and diluted earnings per share of $0.06 per share. Revisions, Reclassifications and Other Adjustments We revised our previously issued financial statements for the nine months ended September 30, 2018 , for the presentation of capital leases in the condensed consolidated statement of cash flow. The effect of the revisions was an increase of $0.2 million to cash provided by operating activities, a $3.0 million decrease to cash required by investing activities and a $3.2 million increase to cash required by financing activities. Certain prior-year amounts have been reclassified to conform to the current presentation. We recorded out-of-period adjustments primarily related to inventory and leased assets write-offs during the three months ended September 30, 2019 which increased revenue by $0.6 million , increased cost of goods and services by $2.6 million and decreased net income by $1.5 million . Management determined the errors were not material to the previously issued condensed consolidated interim financial statements as of and for the three months ended March 31, 2019 and the three and six months ended June 30, 2019. In addition, the correction of the errors in the three months ended September 30, 2019 was not material.

New Accounting Standards

New Accounting Standards	9 Months Ended
	Sep. 30, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
New Accounting Standards	NEW ACCOUNTING STANDARDS Recently Adopted Accounting Standards Effective January 1, 2019, we adopted Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2016-02, “ Leases (Topic 842). ” This update requires a lessee to recognize in the statement of financial position a right-of-use asset representing its right to use the underlying asset for the lease term and a liability for future lease payments. Similar to past guidance, the update continues to differentiate between finance leases and operating leases; however, this distinction now primarily relates to differences in the manner of expense recognition over time and in the classification of lease payments in the statement of cash flows. Additionally, lessors will be required to classify leases as sales-type, finance or operating, with classification affecting the pattern of income recognition. Classification for both lessees and lessors is now based on an assessment of whether a lease contract is economically similar to the purchase of a non-financial asset from the perspective of control. The update also requires quantitative and qualitative disclosures to enable users to understand the amount, timing, and judgments related to leases and the related cash flows. We applied the provisions of this ASU to our lease contracts as of January 1, 2019, using the modified retrospective method of adoption. Prior period amounts have not been adjusted and continue to be reflected in accordance with our historical accounting policies. As of January 1, 2019, we recorded operating lease right-of-use assets of $27.0 million , operating lease liabilities of $28.7 million , and a reduction to retained earnings of $1.7 million as a result of the adoption of this guidance. We have applied the following practical expedients and elections under the new standard: • We elected to utilize the package of transition practical expedients, which among other things, allowed us to carry forward our historical lease classifications for existing leases. • For contracts in which we are a lessee, we have elected to account for each lease component and its associated non-lease components as a single lease component. • We elected to utilize the short term lease exemption for lease contracts with a term of less than 12 months. These contracts are excluded from the measurement of our right-of-use assets and lease liabilities and are recognized in earnings on a straight-line basis over their lease term. • We elected to utilize the practical expedient to exclude sales tax from the measurement of lease revenue. Lessee accounting —Lease liabilities are measured at the lease commencement date and are based on the present value of remaining payments contractually required under the contract. Payments that are variable in nature are excluded from the measurement of our lease liabilities and are recorded as an expense as incurred. Options to renew or extend a lease are included in the measurement of our lease liabilities only when it is reasonably certain that we will exercise these rights. In estimating the present value of our lease liabilities, payments are discounted at our incremental borrowing rate (“IBR”), which has been applied utilizing a portfolio approach. We utilized information publicly available from companies within our industry with similar credit profiles to construct a company-specific yield curve in order to estimate the rate of interest we would pay to borrow at various lease terms. At lease commencement, we recognize a lease right-of-use asset equal to our lease liability, adjusted for lease payments paid to the lessor prior to the lease commencement date, and any initial direct costs incurred. Operating lease expense is recorded on a straight-line basis over the lease term. For finance leases, we amortize our right-of-use assets on a straight-line basis over the shorter of the asset’s useful life or the lease term. Additionally, interest expense is recognized each period related to the accretion of our lease liabilities over their respective lease terms. Lessor accounting —Our lease arrangements generally allow customers to rent equipment on a daily basis with no stated end date. Customers may return the equipment at any point subsequent to the lease commencement date without penalty. We account for these arrangements as a daily renewal option beginning on the lease commencement date, with the lease term determined as the period in which it is reasonably certain the option will be exercised. Based on our assessment of the lease classification criteria, our lease arrangements have been classified as operating leases. Our lease arrangements generally include lease and non-lease components for which revenue is recognized based on each component’s standalone price. Lease revenue is recognized on a straight-line basis over the term of the lease and is included in “Other revenue” in the condensed consolidated statement of income. Non-lease revenue related to our lease arrangements is recognized in accordance with our revenue recognition accounting policy. Assets in our lease program are reported in “Property, plant, and equipment, net” on our condensed consolidated balance sheets and are depreciated over their estimated useful lives to an estimated salvage value. Leased equipment damaged in operation is generally charged to the customer. Charges for damaged leased equipment is recorded as “Product revenue” and the remaining net book value of the leased asset is expensed as “Costs of goods and services” in the condensed consolidated statements of income. See Note 13—Leases for additional information related to our lease accounting. See Note 20—Cash Flow Information for additional information regarding the presentation of our leases within our condensed consolidated statements of cash flows. Effective July 1, 2019, we adopted ASU 2018-15, “ Intangibles—Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. ” The amendments in this update align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by the amendments in this update. The amendments in this update have been applied prospectively to all implementation costs incurred after the date of adoption. The impact of adopting the new standard was not material to our financial statements for the three months ended September 30, 2019 . Recently Issued Accounting Standards In June 2016, the FASB issued ASU 2016-13, “ Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments .” The update amends the impairment model to utilize an expected loss methodology in place of the currently used incurred loss methodology, which may result in earlier recognition of losses related to financial instruments. The guidance will be effective for us on January 1, 2020. Early adoption is permitted for annual periods beginning after December 15, 2018. We do not expect the adoption of this ASU to have a material impact on our financial statements. In August 2018, the FASB issued ASU 2018-14, “ Compensation—Retirement Benefits—Defined Benefit Plans—General (Subtopic 715-20): Disclosure Framework—Changes to the Disclosure Requirements for Defined Benefit Plans.” The amendment modifies certain disclosure requirements for defined benefit plans. Among other requirements and modifications, the amendment requires an explanation of the reasons for significant gains and losses related to changes in the benefit obligation for the period. The guidance will be effective for us with our annual filing for the year ended December 31, 2020. We do not expect the adoption of this ASU to have a material impact on our financial statements.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2019
Related Party Transactions [Abstract]
Related Party Transactions Disclosure [Text Block]	RELATED PARTY TRANSACTIONS Prior to the Separation, Dover provided certain services to us, including corporate executive management, human resources, information technology, facilities, tax, shared services, finance and legal services. Dover continued to provide us certain of these services on a temporary basis following the Separation under a transition services agreement. Under the transition services agreement, Apergy paid a fee to Dover for services rendered under the transition services agreement, which fee was intended to allow Dover to recover all of its direct and indirect costs generally without profit. The transition services agreement was terminated on January 31, 2019, consistent with the initial term provided within the agreement. Financial information presented prior to the Separation does not include all the expenses that would have been incurred had Apergy been a stand-alone public company. The corporate expenses allocated by Dover to these financial statements were $7.4 million for the nine months ended September 30, 2018 , which were recorded in “Selling, general and administrative expense” in the condensed consolidated statement of income. For periods prior to the Separation, transactions between Apergy and Dover are reflected in “Distributions to Dover Corporation, net” in the condensed consolidated statement of cash flows for the nine months ended September 30, 2018, as a financing activity. Revenue with Dover and its affiliates were not material for the periods presented. We recognized royalty expense of $2.3 million for the nine months ended September 30, 2018, related to the use of Dover’s intellectual property and patents which was included in “Other (income) expense, net” in the condensed consolidated statement of income. On April 1, 2018, patents and other intangibles owned by Dover related to our operations transferred to Apergy, and consequently, Apergy no longer incurred royalty charges related to these assets from Dover.

Earnings per Share

Earnings per Share	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Earnings Per Share	EARNINGS PER SHARE On May 9, 2018, 77,339,828 shares of our common stock were distributed to Dover stockholders in conjunction with the Separation. See Note 1—Basis of Presentation and Separation for additional information. For comparative purposes, and to provide a more meaningful calculation of weighted-average shares outstanding, we have assumed the shares issued in conjunction with the Separation to be outstanding as of the beginning of each period prior to the Separation. In addition, we have assumed the potential dilutive securities outstanding as of May 8, 2018, were outstanding and fully dilutive in each of the periods with positive income prior to the Separation. A reconciliation of the number of shares used for the basic and diluted earnings per share calculation was as follows: Three Months Ended September 30, Nine Months Ended September 30, (in thousands, except per share data) 2019 2018 2019 2018 Net income attributable to Apergy $ 10,225 $ 25,264 $ 56,291 $ 71,470 Weighted-average number of shares outstanding 77,460 77,340 77,416 77,340 Dilutive effect of stock-based compensation 113 229 199 402 Total shares and dilutive securities 77,573 77,569 77,615 77,742 Basic earnings per share attributable to Apergy $ 0.13 $ 0.33 $ 0.73 $ 0.92 Diluted earnings per share attributable to Apergy $ 0.13 $ 0.33 $ 0.73 $ 0.92

Acquisitions (Notes)

Acquisitions (Notes)	9 Months Ended
	Sep. 30, 2019
Business Combinations [Abstract]
Business Combination Disclosure [Text Block]	ACQUISITIONS On July 31, 2019, Apergy entered into an asset purchase agreement to acquire certain assets, which meet the definition of a business, used in the manufacturing of downhole monitoring systems. The acquisition is included among the consolidated subsidiaries reported in our Production & Automation Technologies segment and provides digital technology strategic to our artificial lift product offering. The acquisition-date fair value of the consideration transferred consisted of the following: (in thousands) Cash $ 12,500 Contingent consideration (1) 1,500 Total consideration transferred $ 14,000 _______________________ (1) Contingent consideration is payable to the seller based on the acquired business exceeding a revenue target over an eighteen month period ending January 2021. Achievement of the revenue target is considered probable. The following table summarizes the final fair values of the assets acquired at the acquisition date: (in thousands) Inventory $ 1,840 Customer relationships 2,650 Technology - Technical know-how 4,000 Goodwill 5,510 Total assets acquired $ 14,000 The amortization period is 15 years for acquired customer relationships and technology. The goodwill recognized as a result of the acquisition is tax deductible and primarily reflects the expected benefits to be derived from operational synergies. Results of operations of the acquired business have been included in our condensed consolidated financial statements as of the acquisition date. Pro forma results of operations have not been presented as the effects of the acquisition are not material to our condensed consolidated financial statements.

Dispositions (Notes)

Dispositions (Notes)	9 Months Ended
	Sep. 30, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]	DISPOSITIONS During March 2019, we classified our pressure vessel manufacturing business in our Production & Automated Technologies segment as held for sale. We recognized an impairment loss of $1.7 million during the nine months ended September 30, 2019, which was recorded in “Selling, general and administrative expense” in the condensed consolidated statement of income, to adjust the carrying amount of the disposal group to fair value. See Note 17—Fair Value Measurements for additional information. In June 2019, we completed the sale of our pressure vessel manufacturing business and made a cash payment of $2.2 million , resulting in a loss on disposition of $2.5 million , which was recorded in “Other (income) expense, net” in the condensed consolidated statement of income for the nine months ended September 30, 2019.

Inventories

Inventories	9 Months Ended
	Sep. 30, 2019
Inventory, Net [Abstract]
Inventories	INVENTORIES Inventories consisted of the following: (in thousands) September 30, 2019 December 31, 2018 Raw materials $ 49,752 $ 52,057 Work in progress 14,603 11,416 Finished goods 179,548 180,624 243,903 244,097 LIFO and valuation adjustments (24,289 ) (25,778 ) Inventories, net $ 219,614 $ 218,319

Goodwill

Goodwill	9 Months Ended
	Sep. 30, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	GOODWILL The carrying amount of goodwill, including changes therein, by reporting segment was as follows: (in thousands) Production & Automation Technologies Drilling Technologies Total December 31, 2018 $ 803,849 $ 101,136 $ 904,985 Acquisition 5,510 — 5,510 Foreign currency translation 198 — 198 September 30, 2019 $ 809,557 $ 101,136 $ 910,693

Debt

Debt	9 Months Ended
	Sep. 30, 2019
Debt Disclosure [Abstract]
Debt	DEBT Long-term debt consisted of the following: (in thousands) September 30, 2019 December 31, 2018 Revolving credit facility $ — $ — Term loan facility 295,000 370,000 6.375% Senior Notes due 2026 300,000 300,000 Finance lease obligations 3,706 7,485 Total 598,706 677,485 Net unamortized discounts and issuance costs (10,126 ) (11,377 ) Total long-term debt $ 588,580 $ 666,108

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Guarantees and Indemnifications We have provided indemnities in connection with sales of certain businesses and assets, including representations and warranties, covenants and related indemnities for environmental health and safety, tax and employment matters. We do not have any material liabilities recorded for these indemnifications and are not aware of any claims or other information that would give rise to material payments under such indemnities. In connection with the Separation, we entered into agreements with Dover that govern the treatment between Dover and us for certain indemnification matters and litigation responsibility. Generally, the separation and distribution agreement provides for cross-indemnities principally designed to place financial responsibility for the obligations and liabilities of our business with us and to place financial responsibility for the obligations and liabilities of Dover’s business with Dover. The separation and distribution agreement also establishes procedures for handling claims subject to indemnification and related matters. In addition, pursuant to the tax matters agreement, we have agreed to indemnify Dover and its affiliates against any and all tax-related liabilities incurred by them relating to the Separation and/or certain related transactions to the extent caused by an acquisition of Apergy stock or assets or by any other action or failure to act undertaken by Apergy or its affiliates. During the three months ended September 30, 2019 , and pursuant to the provisions of the tax matters agreement with Dover, we recognized $3.4 million of indemnification expense within “Selling, general and administrative expense” in the condensed consolidated statements of income with respect to certain liabilities related to tax audits for the 2012-2016 tax years. The tax audits and related assessments have not been completed. As of September 30, 2019 and December 31, 2018 , we had $13.0 million and $3.6 million , respectively, of outstanding letters of credit, surety bonds and guarantees which expire at various dates through 2025. These financial instruments are primarily maintained as security for insurance, warranty and other performance obligations. Generally, we would only be liable for the amount of these letters of credit and surety bonds in the event of default in the performance of our obligations, the probability of which we believe is remote. Litigation and Environmental Matters We are involved in various pending or potential legal actions in the ordinary course of our business. These proceedings primarily involve claims by private parties alleging injury arising out of use of our products, patent infringement, employment matters, and commercial disputes. We review the probable outcome of such proceedings, the costs and expenses reasonably expected to be incurred and accrued to-date, and the availability and extent of insurance coverage. We accrue a liability for legal matters that are probable and estimable, and as of September 30, 2019 and December 31, 2018 , these liabilities were not material. Management is unable to predict the ultimate outcome of these actions because of the inherent uncertainty of litigation. However, management believes the most probable, ultimate resolution of these matters will not have a material adverse effect on our consolidated financial position, results of operations or cash flows. Prior to the Separation, groundwater contamination was discovered at the Norris Sucker Rods plant site located in Tulsa, Oklahoma ("Norris"). Initial remedial efforts were undertaken at the time of discovery of the contamination and Norris has since coordinated monitoring and remediation with the Oklahoma Department of Environmental Quality ("ODEQ"). As part of the ongoing long-term remediation process, Norris contracted an engineering and consulting firm to develop a range of possible additional remedial alternatives in order to accelerate the remediation process and associated cost estimates for the work. In October 2019, we received the firm’s preliminary remedial alternatives for consideration. Now that we have such recommendations, we expect to begin discussions with ODEQ regarding our proposed long-term remediation plan. The plan is subject to ODEQ’s review, input, and approval. Because we have not yet finalized a plan for further remediation at the site and discussions with ODEQ remain ongoing, we cannot fully anticipate the timing, outcome or possible impact of such further remedial activities, financial or otherwise. At September 30, 2019 , as a result of the recommendations in the report, we have accrued liabilities for these remediation efforts of approximately $2.0 million with such charges recorded within “Selling, general and administrative expense” in the condensed consolidated statements of income. Liabilities could increase in the future at such time as we ultimately reach agreement with ODEQ on our remediation plan and such liabilities become probable and can be reasonably estimated.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2019
Stockholders' Equity Note [Abstract]
Stockholders' Equity	STOCKHOLDERS' EQUITY Capital stock —The following is a summary of our capital stock activity: (in thousands) Common Stock March 31, 2018 — Issuance of common stock 77,340 June 30, 2018 77,340 Shares issued—share-based compensation 1 September 30, 2018 77,341 (in thousands) Common Stock December 31, 2018 77,353 Shares issued—share-based compensation 39 March 31, 2019 77,392 Shares issued—share-based compensation 67 June 30, 2019 77,459 Shares issued—share-based compensation 1 September 30, 2019 77,460 Accumulated other comprehensive loss —Accumulated other comprehensive loss consisted of the following: (in thousands) Foreign Currency Translation Defined Pension and Other Post-Retirement Benefits Accumulated Other Comprehensive Loss December 31, 2017 $ (21,936 ) $ (4,480 ) $ (26,416 ) Reclassification adjustment for cumulative effect of change in accounting principle — (1,315 ) (1,315 ) Other comprehensive loss before reclassifications, net of tax (1,691 ) — (1,691 ) Reclassification adjustment for net losses included in net income, net of tax — 49 49 Other comprehensive income (loss), net of tax (1,691 ) 49 (1,642 ) March 31, 2018 (23,627 ) (5,746 ) (29,373 ) Net transfer from Dover — (1,450 ) (1,450 ) Other comprehensive income (loss) before reclassifications, net of tax (6,874 ) 170 (6,704 ) Reclassification adjustment for net losses included in net income, net of tax — 46 46 Other comprehensive income (loss), net of tax (6,874 ) 216 (6,658 ) June 30, 2018 (30,501 ) (6,980 ) (37,481 ) Net transfer from Dover — (970 ) (970 ) Other comprehensive loss before reclassifications, net of tax (515 ) — (515 ) Reclassification adjustment for net losses included in net income, net of tax — 439 439 Other comprehensive income (loss), net of tax (515 ) 439 (76 ) September 30, 2018 $ (31,016 ) $ (7,511 ) $ (38,527 ) (in thousands) Foreign Currency Translation Defined Pension and Other Post-Retirement Benefits Accumulated Other Comprehensive Loss December 31, 2018 $ (36,146 ) $ (6,760 ) $ (42,906 ) Other comprehensive income (loss) before reclassifications, net of tax 1,090 (323 ) 767 Reclassification adjustment for net losses included in net income, net of tax — 422 422 Other comprehensive income, net of tax 1,090 99 1,189 March 31, 2019 (35,056 ) (6,661 ) (41,717 ) Other comprehensive income before reclassifications, net of tax 974 — 974 Reclassification adjustment for net losses included in net income, net of tax — 68 68 Other comprehensive income, net of tax 974 68 1,042 June 30, 2019 (34,082 ) (6,593 ) (40,675 ) Other comprehensive loss before reclassifications, net of tax (2,900 ) — (2,900 ) Reclassification adjustment for net losses included in net income, net of tax — 68 68 Other comprehensive income (loss), net of tax (2,900 ) 68 (2,832 ) September 30, 2019 $ (36,982 ) $ (6,525 ) $ (43,507 ) Reclassifications from accumulated other comprehensive loss —Reclassification adjustments from accumulated other comprehensive loss to net income related to defined pension and other post-retirement benefits consisted of the following: Three Months Ended September 30, Nine Months Ended September 30, Affected line items on the condensed consolidated statements of income (in thousands) 2019 2018 2019 2018 Amortization of actuarial loss and other (1) $ 91 $ 116 $ 274 $ 242 Other (income) expense, net Settlement loss (1) — 484 486 484 Other (income) expense, net Total before tax 91 600 760 726 Income before income taxes Tax benefit (23 ) (161 ) (202 ) (192 ) Provision for income taxes $ 68 $ 439 $ 558 $ 534 Net income _______________________ (1) These accumulated other comprehensive loss components are included in the computation of net periodic benefit cost (See Note 15—Employee Benefit Plans for additional information).

Revenue

Revenue	9 Months Ended
	Sep. 30, 2019
Revenue from Contract with Customer [Abstract]
Revenue	REVENUE Disaggregation of Revenue Revenue disaggregated by revenue type was as follows: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2019 2018 2019 2018 Product revenue $ 244,651 $ 283,102 $ 787,698 $ 807,949 Service revenue 20,708 20,471 62,056 62,014 Lease and other revenue 13,022 12,895 36,372 35,481 Total revenue $ 278,381 $ 316,468 $ 886,126 $ 905,444 Revenue disaggregated by end market in each of our reporting segments was as follows: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2019 2018 2019 2018 Drilling Technologies $ 54,878 $ 75,254 $ 202,764 $ 209,727 Production & Automation Technologies: Artificial lift 176,253 187,872 531,127 543,302 Digital products 34,460 31,248 100,056 86,761 Other production equipment 13,245 22,380 53,083 66,444 Intra-segment eliminations (455 ) (286 ) (904 ) (790 ) 223,503 241,214 683,362 695,717 Total revenue $ 278,381 $ 316,468 $ 886,126 $ 905,444 Revenue disaggregated by geography was as follows: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2019 2018 2019 2018 United States $ 210,905 $ 252,747 $ 680,396 $ 712,499 Canada 19,224 20,759 54,009 58,639 Middle East 16,317 13,645 44,360 40,091 Europe 10,468 7,625 40,518 27,805 Latin America 6,835 8,364 23,936 25,097 Australia 8,002 8,939 22,009 24,951 Asia-Pacific and other 6,630 4,389 20,898 16,362 Total revenue $ 278,381 $ 316,468 $ 886,126 $ 905,444 Revenue is attributed to regions based on the location of our direct customer, which in some instances is an intermediary and not necessarily the end user. Contract balances Contract assets and contract liabilities from contracts with customers were as follows: (in thousands) September 30, 2019 December 31, 2018 Contract assets $ 2,044 $ 4,571 Contract liabilities - current 6,798 5,863

Leases (Notes)

Leases (Notes)	9 Months Ended
	Sep. 30, 2019
Leases [Abstract]
Lessor and Lessee Leases [Text Block]	LEASES Lessee Accounting We have operating and finance leases for real estate, vehicles and equipment. Certain of our vehicle leases include residual value guarantees, which have been excluded from the measurement of our lease liabilities as we do not believe it is probable the residual value guarantees will be paid at the end of the lease. Our real estate and vehicle leases generally include options to renew or extend the lease term at our discretion. These options are included in the measurement of our lease liabilities only when it is reasonably certain that we will exercise these rights. Balance sheet presentation —Leases are presented in our condensed consolidated balance sheet as follows: (in thousands) Balance Sheet Classification September 30, 2019 Right-of Use Assets: Finance leases Property, plant, and equipment, net $ 8,115 Operating leases Other non-current assets 21,604 Total lease right-of-use assets 29,719 Lease Liabilities: Finance leases - current Accrued expenses and other current liabilities 4,336 Finance leases Long-term debt 3,706 Operating leases - current Accrued expenses and other current liabilities 7,709 Operating leases Other long-term liabilities 16,758 Total lease liabilities $ 32,509 Components of total lease cost —Components of total lease cost were as follows: (in thousands) Three Months Ended September 30, 2019 Nine Months Ended September 30, 2019 Finance lease cost: Amortization of right-of-use assets $ 1,041 $ 3,717 Interest on lease liabilities 60 293 Operating lease cost 2,302 8,140 Short-term lease cost 1,331 3,253 Variable lease cost 145 707 Sublease income (133 ) (367 ) Total net lease cost $ 4,746 $ 15,743 Lease term and discount rate —Our weighted-average remaining lease term and weighted-average discount rate for operating and finance leases are as follows: September 30, 2019 Weighted-average remaining lease term (years): Operating lease 4.6 Finance lease 2.0 Weighted-average discount rate: Operating lease 6.6 % Finance lease 5.2 % Maturity Analysis —Future minimum payments on our operating and finance leases as of September 30, 2019 are as follows: (in thousands) Operating Finance 2019 $ 2,482 $ 1,509 2020 7,823 4,114 2021 4,646 2,368 2022 3,934 420 2023 3,471 77 Thereafter 7,017 2 Total future minimum lease payments 29,373 8,490 Interest included within lease payments (4,906 ) (448 ) Total lease liabilities $ 24,467 $ 8,042 Lessor Accounting Lease revenue is primarily generated from our electric submersible pump (“ESP”) leased asset program within our Production & Automation Technologies segment. Our lease arrangements generally allow customers to rent equipment on a daily basis with no stated end date. Customers may return the equipment at any point subsequent to the lease commencement date without penalty. We account for these arrangements as a daily renewal option beginning on the lease commencement date, with the lease term determined as the period in which it is reasonably certain the option will be exercised. The average length of these arrangements generally range from six months to nine months. Lease revenue was $11.6 million and $32.8 million for the three and nine month periods ended September 30, 2019 , respectively. Leased assets —Components of our leased assets are as follows: (in thousands) September 30, 2019 Property, plant, and equipment $ 170,889 Accumulated depreciation (69,993 ) Property, plant, and equipment, net $ 100,896 Depreciation expense on our leased assets was $9.5 million and $27.3 million for the three month and nine month periods ended September 30, 2019 , respectively.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES Prior to the Separation, the operations of Apergy were included in Dover’s U.S. combined federal and state income tax returns. Consequently, income tax expense is presented for the pre-Separation periods as if Apergy filed its own tax returns in each jurisdiction and include tax losses and tax credits that may not reflect tax positions taken by Dover. In many cases, tax losses and tax credits generated by Apergy prior to the Separation have been utilized by Dover. Our income tax provision reflected effective tax rates of 22.7% and 23.2% for the three months ended September 30, 2019 and 2018 , respectively, and 21.6% and 25.2% for the nine months ended September 30, 2019 and 2018 , respectively. The year-over-year decrease in the effective rates reflects tax benefits for foreign tax basis step-up, stock compensation, and favorable U.S. state tax rate changes. Additionally, the year-over-year decrease in the effective tax rates includes a one-time charge during the nine months ended September 30, 2018 related to certain reorganizations of our subsidiaries as a result of the Separation.

Employee Benefit Plans

Employee Benefit Plans	9 Months Ended
	Sep. 30, 2019
Defined Benefit Plan [Abstract]
Employee Benefit Plans	EMPLOYEE BENEFIT PLANS Prior to the Separation, certain of our employees participated in defined benefit and non-qualified plans sponsored by Dover, which included participants of other Dover subsidiaries. For periods prior to the Separation, we accounted for such plans as multi-employer benefit plans and recorded a proportionate share of the cost in our condensed consolidated statements of income. Total net periodic benefit cost was $0.4 million and $1.1 million for the three months ended September 30, 2019 and 2018 , respectively, and $1.5 million and $2.9 million for the nine months ended September 30, 2019 and 2018 , respectively. Prior to the Separation, our net periodic benefit costs included benefit costs associated with plans accounted for as single-employer plans and an allocation from Dover for plans accounted for as multi-employer plans. After the Separation, total net periodic benefit costs include all costs associated with the plans we sponsor, including plans that transferred to Apergy.

Equity and Cash Incentive Progr

Equity and Cash Incentive Program	9 Months Ended
	Sep. 30, 2019
Share-based Payment Arrangement, Noncash Expense [Abstract]
Equity and Cash Incentive Program	EQUITY AND CASH INCENTIVE PROGRAM Prior to the Separation, Dover granted share-based awards to its officers and other key employees, including certain Apergy individuals. All awards granted under the program consisted of Dover common shares and are not necessarily indicative of the results that Apergy would have experienced as a stand-alone public company for the periods presented prior to the Separation. Effective with the Separation, outstanding Dover share-based awards were converted to Apergy share-based awards, with the exception of outstanding Dover performance share awards that relate to performance periods ending after the Separation. Such performance share awards were cancelled effective with the Separation. Stock-based compensation expense is reported within “Selling, general and administrative expense” in the condensed consolidated statements of income. Stock-based compensation expense relating to all stock-based incentive plans was as follows: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2019 2018 2019 2018 Stock-based compensation expense $ 2,524 $ 1,768 $ 7,545 $ 3,129 Tax benefit (615 ) (421 ) (1,841 ) (717 ) Stock-based compensation expense, net of tax $ 1,909 $ 1,347 $ 5,704 $ 2,412 A summary of activity relating to our share-based awards for the nine months ended September 30, 2019 , is as follows: (in shares) Stock-Settled Appreciation Rights Performance Share Awards Restricted Stock Units Outstanding at January 1, 2019 477,950 86,817 414,840 Granted — 92,919 155,777 Forfeited (7,030 ) (5,010 ) (16,032 ) Exercised / Vested (46,125 ) — (141,437 ) Outstanding at September 30, 2019 424,795 174,726 413,148

Fair Value Measurements (Notes)

Fair Value Measurements (Notes)	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS We had no outstanding derivative contracts as of September 30, 2019 and December 31, 2018 . Other assets and liabilities measured at fair value on a recurring basis as of September 30, 2019 and December 31, 2018 , were not significant; thus, no fair value disclosures are presented. The fair value, based on Level 1 quoted market rates, of our Senior Notes was approximately $300.0 million at September 30, 2019 , as compared to the $300.0 million face value of the debt. The fair value, based on Level 2 quoted market rates, of our term loan facility was approximately $295.6 million at September 30, 2019 , as compared to the $295.0 million face value of the debt. The carrying amounts of cash and cash equivalents, trade receivables, accounts payable, as well as amounts included in other current assets and other current liabilities that meet the definition of financial instruments, approximate fair value due to their short-term nature. Impairment of Assets Held For Sale In March 2019, we classified our pressure vessel manufacturing business in our Production & Automation Technologies segment as held for sale and recognized an impairment loss of $1.7 million to adjust the carrying amount of the disposal group to fair value. The fair value was determined by a negotiated selling price through a non-binding expression of interest with a third party, a Level 3 input. We completed the sale of our pressure vessel manufacturing business in June 2019. See Note 6—Dispositions for additional information. Acquisition On July 31, 2019, Apergy entered into an asset purchase agreement to acquire certain assets, which meet the definition of a business. See Note 5—Acquisitions for additional information. The fair value of the contingent consideration is based on the probability of the acquired business achieving an eighteen month revenue target, a Level 3 input. As of September 30, 2019, the estimated fair value of the contingent consideration liability was $1.5 million , as attainment of the revenue target was deemed probable. Credit Risk By their nature, financial instruments involve risk, including credit risk, for non-performance by counterparties. Financial instruments that potentially subject us to credit risk primarily consist of trade receivables. We manage the credit risk on financial instruments by transacting only with what management believes are financially secure counterparties, requiring credit approvals and credit limits, and monitoring counterparties’ financial condition. Our maximum exposure to credit loss in the event of non-performance by the counterparty is limited to the amount drawn and outstanding on the financial instrument. Allowances for losses on trade receivables are established based on collectability assessments.

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2019
Segment Reporting [Abstract]
Segment Information	SEGMENT INFORMATION We report our results of operations in the following reporting segments: Production & Automation Technologies and Drilling Technologies. Segment revenue and segment operating profit were as follows: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2019 2018 2019 2018 Segment revenue: Production & Automation Technologies $ 223,503 $ 241,214 $ 683,362 $ 695,717 Drilling Technologies 54,878 75,254 202,764 209,727 Total revenue $ 278,381 $ 316,468 $ 886,126 $ 905,444 Income before income taxes: Segment operating profit: Production & Automation Technologies $ 17,329 $ 24,175 $ 54,411 $ 57,272 Drilling Technologies 13,796 26,209 64,853 71,738 Total segment operating profit 31,125 50,384 119,264 129,010 Corporate expense and other (1) 8,110 6,581 16,686 16,273 Interest expense, net 9,537 10,584 30,068 16,813 Income before income taxes $ 13,478 $ 33,219 $ 72,510 $ 95,924 _______________________ (1) Corporate expense and other includes costs not directly attributable or allocated to our reporting segments such as corporate executive management and other administrative functions, costs related to our Separation from Dover and the results attributable to our noncontrolling interest.

Condensed Consolidating Financi

Condensed Consolidating Financial Statements (Notes)	9 Months Ended
	Sep. 30, 2019
Condensed Financial Information Disclosure [Abstract]
Condensed Financial Information of Parent Company Only Disclosure [Text Block]	CONDENSED CONSOLIDATING FINANCIAL INFORMATION Apergy Corporation has senior notes outstanding, the payment obligations of which are fully and unconditionally guaranteed by certain 100-percent-owned subsidiaries of Apergy on a joint and several basis. The following financial information presents the results of operations, financial position and cash flows for: • Apergy Corporation (issuer); • 100-percent-owned guarantor subsidiaries; • All other non-guarantor subsidiaries; and • Adjustments and eliminations necessary to present Apergy results on a consolidated basis. This condensed consolidating financial information should be read in conjunction with the accompanying condensed consolidated financial statements and related notes. Three Months Ended September 30, 2019 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Product revenue $ — $ 211,988 $ 32,663 $ — $ 244,651 Other revenue — 31,664 14,278 (12,212 ) 33,730 Total revenue — 243,652 46,941 (12,212 ) 278,381 Cost of goods and services — 162,031 36,979 (12,148 ) 186,862 Gross profit — 81,621 9,962 (64 ) 91,519 Selling, general and administrative expense 64 62,289 6,460 — 68,813 Interest expense, net 9,502 32 3 — 9,537 Other (income) expense, net — (1,011 ) 702 — (309 ) Income (loss) before income taxes and equity in earnings of affiliates (9,566 ) 20,311 2,797 (64 ) 13,478 Provision for (benefit from) income taxes (2,180 ) 2,181 3,072 (14 ) 3,059 Income (loss) before equity in earnings of affiliates (7,386 ) 18,130 (275 ) (50 ) 10,419 Equity in earnings of affiliates 17,611 5,926 5,841 (29,378 ) — Net income 10,225 24,056 5,566 (29,428 ) 10,419 Net income attributable to noncontrolling interest — — 194 — 194 Net income attributable to Apergy $ 10,225 $ 24,056 $ 5,372 $ (29,428 ) $ 10,225 Comprehensive income attributable to Apergy $ 7,393 $ 23,079 $ 3,501 $ (26,580 ) $ 7,393 Three Months Ended September 30, 2018 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Product revenue $ — $ 250,549 $ 32,553 $ — $ 283,102 Other revenue — 32,230 11,933 (10,797 ) 33,366 Total revenue — 282,779 44,486 (10,797 ) 316,468 Cost of goods and services — 175,718 37,899 (10,883 ) 202,734 Gross profit — 107,061 6,587 86 113,734 Selling, general and administrative expense 86 63,659 5,461 — 69,206 Interest expense, net 10,492 84 9 (1 ) 10,584 Other (income) expense, net — (711 ) 1,435 1 725 Income (loss) before income taxes and equity in earnings of affiliates (10,578 ) 44,029 (318 ) 86 33,219 Provision for (benefit from) income taxes (2,574 ) 8,743 1,536 18 7,723 Income (loss) before equity in earnings of affiliates (8,004 ) 35,286 (1,854 ) 68 25,496 Equity in earnings of affiliates 33,268 5,347 12,604 (51,219 ) — Net income 25,264 40,633 10,750 (51,151 ) 25,496 Net income attributable to noncontrolling interest — — 232 — 232 Net income attributable to Apergy $ 25,264 $ 40,633 $ 10,518 $ (51,151 ) $ 25,264 Comprehensive income attributable to Apergy $ 25,188 $ 39,903 $ 11,171 $ (51,074 ) $ 25,188 Nine Months Ended September 30, 2019 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Product revenue $ — $ 700,014 $ 87,684 $ — $ 787,698 Other revenue — 90,801 39,751 (32,124 ) 98,428 Total revenue — 790,815 127,435 (32,124 ) 886,126 Cost of goods and services — 505,375 106,122 (32,208 ) 579,289 Gross profit — 285,440 21,313 84 306,837 Selling, general and administrative expense 207 182,867 17,716 — 200,790 Interest expense, net 29,791 256 21 — 30,068 Other expense, net — 1,952 1,517 — 3,469 Income (loss) before income taxes and equity in earnings of affiliates (29,998 ) 100,365 2,059 84 72,510 Provision for (benefit from) income taxes (6,918 ) 21,122 1,450 18 15,672 Income (loss) before equity in earnings of affiliates (23,080 ) 79,243 609 66 56,838 Equity in earnings of affiliates 79,371 14,974 18,015 (112,360 ) — Net income 56,291 94,217 18,624 (112,294 ) 56,838 Net income attributable to noncontrolling interest — — 547 — 547 Net income attributable to Apergy $ 56,291 $ 94,217 $ 18,077 $ (112,294 ) $ 56,291 Comprehensive income attributable to Apergy $ 55,690 $ 93,750 $ 17,932 $ (111,682 ) $ 55,690 Nine Months Ended September 30, 2018 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Product revenue $ — $ 713,865 $ 94,084 $ — $ 807,949 Other revenue — 95,284 34,374 (32,163 ) 97,495 Total revenue — 809,149 128,458 (32,163 ) 905,444 Cost of goods and services — 514,816 111,142 (31,542 ) 594,416 Gross profit — 294,333 17,316 (621 ) 311,028 Selling, general and administrative expense 1,588 176,539 16,247 — 194,374 Interest expense, net 16,494 288 32 (1 ) 16,813 Other expense, net — 2,065 1,851 1 3,917 Income (loss) before income taxes and equity in earnings of affiliates (18,082 ) 115,441 (814 ) (621 ) 95,924 Provision for (benefit from) income taxes (4,217 ) 23,911 4,595 (130 ) 24,159 Income (loss) before equity in earnings of affiliates (13,865 ) 91,530 (5,409 ) (491 ) 71,765 Equity in earnings of affiliates 85,335 18,292 37,049 (140,676 ) — Net income 71,470 109,822 31,640 (141,167 ) 71,765 Net income attributable to noncontrolling interest — — 295 — 295 Net income attributable to Apergy $ 71,470 $ 109,822 $ 31,345 $ (141,167 ) $ 71,470 Comprehensive income attributable to Apergy $ 63,094 $ 109,177 $ 23,614 $ (132,791 ) $ 63,094 September 30, 2019 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Assets Cash and cash equivalents $ 108 $ 29,041 $ 11,478 $ — $ 40,627 Receivables, net 394 206,521 38,300 (8,834 ) 236,381 Inventories, net — 188,555 32,609 (1,550 ) 219,614 Prepaid expenses and other current assets 78 29,793 4,645 — 34,516 Total current assets 580 453,910 87,032 (10,384 ) 531,138 Property, plant and equipment, net — 237,649 11,736 — 249,385 Goodwill — 633,771 276,922 — 910,693 Advances due from affiliates 536,389 20,230 88,035 (644,654 ) — Investment in subsidiaries 1,096,182 713,088 563,185 (2,372,455 ) — Intangible assets, net — 171,259 80,152 — 251,411 Other non-current assets 3,304 19,011 7,311 — 29,626 Total assets 1,636,455 2,248,918 1,114,373 (3,027,493 ) 1,972,253 Liabilities and Equity Accounts payable 24 102,808 20,187 (8,834 ) 114,185 Accrued compensation and employee benefits — 34,301 6,115 — 40,416 Accrued expenses and other current liabilities 9,750 33,536 10,116 (1,550 ) 51,852 Total current liabilities 9,774 170,645 36,418 (10,384 ) 206,453 Advances due to affiliates — 624,424 20,230 (644,654 ) — Long-term debt 584,875 3,586 119 — 588,580 Deferred income taxes — 80,735 16,853 — 97,588 Other long-term liabilities — 32,277 5,549 — 37,826 Total liabilities 594,649 911,667 79,169 (655,038 ) 930,447 Equity Total stockholders’ equity 1,041,806 1,337,251 1,032,199 (2,372,455 ) 1,038,801 Noncontrolling interest — — 3,005 — 3,005 Total equity 1,041,806 1,337,251 1,035,204 (2,372,455 ) 1,041,806 Total liabilities and equity $ 1,636,455 $ 2,248,918 $ 1,114,373 $ (3,027,493 ) $ 1,972,253 December 31, 2018 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Assets Cash and cash equivalents $ 108 $ 27,533 $ 14,191 $ — $ 41,832 Receivables, net 1,743 230,230 35,019 (17,044 ) 249,948 Inventories, net — 189,015 30,936 (1,632 ) 218,319 Prepaid expenses and other current assets 24,583 17,064 3,106 (24,542 ) 20,211 Total current assets 26,434 463,842 83,252 (43,218 ) 530,310 Property, plant and equipment, net — 231,373 12,955 — 244,328 Goodwill — 633,771 271,214 — 904,985 Advances due from affiliates 600,802 14,185 82,889 (697,876 ) — Investment in subsidiaries 1,013,869 687,691 545,298 (2,246,858 ) — Intangible assets, net — 198,531 85,157 — 283,688 Other non-current assets 3,996 2,371 2,078 — 8,445 Total assets 1,645,101 2,231,764 1,082,843 (2,987,952 ) 1,971,756 Liabilities and Equity Accounts payable 22 114,745 33,335 (17,044 ) 131,058 Accrued compensation and employee benefits — 35,278 5,268 — 40,546 Accrued expenses and other current liabilities 4,929 46,722 4,914 (26,174 ) 30,391 Total current liabilities 4,951 196,745 43,517 (43,218 ) 201,995 Advances due to affiliates — 683,700 14,176 (697,876 ) — Long-term debt 658,623 7,363 122 — 666,108 Deferred income taxes — 81,296 20,428 — 101,724 Other long-term liabilities — 19,441 961 — 20,402 Total liabilities 663,574 988,545 79,204 (741,094 ) 990,229 Equity Total stockholders’ equity 981,527 1,243,219 1,001,181 (2,246,858 ) 979,069 Noncontrolling interest — — 2,458 — 2,458 Total equity 981,527 1,243,219 1,003,639 (2,246,858 ) 981,527 Total liabilities and equity $ 1,645,101 $ 2,231,764 $ 1,082,843 $ (2,987,952 ) $ 1,971,756 Nine Months Ended September 30, 2019 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Cash provided (required) by operating activities $ (36,254 ) $ 161,085 $ (1,441 ) $ — $ 123,390 Cash provided (required) by investing activities: Capital expenditures — (30,387 ) (1,202 ) — (31,589 ) Proceeds from sale of fixed assets — 2,935 19 — 2,954 Payment on sale of business — (2,194 ) — — (2,194 ) Payment on acquisition — (12,500 ) — — (12,500 ) Net cash required by investing activities — (42,146 ) (1,183 ) — (43,329 ) Cash provided (required) by financing activities: Proceeds from long-term debt 36,500 — — — 36,500 Repayment of long-term debt (111,500 ) — — — (111,500 ) Advances due to (from) affiliates 111,254 (111,573 ) 319 — — Payments of finance lease obligations — (4,070 ) (38 ) — (4,108 ) Payments related to taxes withheld on stock-based compensation — (1,788 ) (53 ) — (1,841 ) Net cash provided (required) by financing activities 36,254 (117,431 ) 228 — (80,949 ) Effect of exchange rate changes on cash and cash equivalents — — (317 ) — (317 ) Net increase (decrease) in cash and cash equivalents — 1,508 (2,713 ) — (1,205 ) Cash and cash equivalents at beginning of period 108 27,533 14,191 — 41,832 Cash and cash equivalents at end of period $ 108 $ 29,041 $ 11,478 $ — $ 40,627 Nine Months Ended September 30, 2018 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Cash provided (required) by operating activities $ (16,694 ) $ 104,136 $ 6,588 $ (999 ) $ 93,031 Cash provided (required) by investing activities: Capital expenditures — (40,797 ) (2,086 ) — (42,883 ) Proceeds from sale of fixed assets — 938 32 — 970 Purchase price adjustments on acquisition — — 53 — 53 Net cash required by investing activities — (39,859 ) (2,001 ) — (41,860 ) Cash provided (required) by financing activities: Proceeds from long-term debt, net of discounts 713,963 — — — 713,963 Payment of debt issue costs (16,006 ) — — — (16,006 ) Repayment of long-term debt (20,000 ) — — — (20,000 ) Advances due to (from) affiliates (660,836 ) 677,999 (17,163 ) — — Distributions to Dover Corporation, net (319 ) (736,557 ) 7,020 999 (728,857 ) Distribution to noncontrolling interest — — (2,720 ) — (2,720 ) Payments of finance lease obligations — (3,174 ) — — (3,174 ) Net cash provided (required) by financing activities 16,802 (61,732 ) (12,863 ) 999 (56,794 ) Effect of exchange rate changes on cash and cash equivalents — — (75 ) — (75 ) Net increase (decrease) in cash and cash equivalents 108 2,545 (8,351 ) — (5,698 ) Cash and cash equivalents at beginning of period — 5,763 17,949 — 23,712 Cash and cash equivalents at end of period $ 108 $ 8,308 $ 9,598 $ — $ 18,014

Cash Flow Information (Notes)

Cash Flow Information (Notes)	9 Months Ended
	Sep. 30, 2019
Supplemental Cash Flow Elements [Abstract]
Cash Flow, Supplemental Disclosures [Text Block]	CASH FLOW INFORMATION Supplemental cash flow information is as follows: (in thousands) Statement of Cash Flows Classification Nine Months Ended September 30, 2019 Cash information: Cash required by operating leases (1) Operating $ 8,955 Cash required by finance leases - interest Operating 295 Cash required by finance leases - principal Financing 4,108 Non-cash information: Operating lease additions (2) Non-cash $ 34,961 Finance lease additions Non-cash 3,990 _______________________ (1) Cash required by operating leases is reported net of operating lease expense in the operating section of our condensed consolidated statements of cash flows in “Accrued expenses and other liabilities.” (2) Operating lease additions include lease liabilities recognized at the time of adoption. Refer to Note 2—New Accounting Standards for additional information. Lease program Our ESP leased asset program is reported in our Production & Automation Technologies segment. At the time of purchase, assets are recorded to inventory and are transferred to property, plant, and equipment when a customer contracts for an asset under our lease program. During the nine months ended September 30, 2019 , we transferred $61.2 million of inventory into property, plant, and equipment as a result of assets entering our leased asset program. Expenditures for assets that are expected to be placed into our lease asset program and with a useful life of greater than one year are reported in “Capital expenditures” in the investing section of our condensed consolidated statements of cash flows. During the nine months ended September 30, 2019 and 2018 , such expenditures were estimated to be $13.9 million , and $17.3 million , respectively. Expenditures for assets that are expected to be placed into our leased asset program and with a useful life of one year are reported in “Leased assets” in the operating section of our condensed consolidated statement of cash flows. Additionally, the recovery of the carrying value from the sale of assets on lease is presented in “Leased assets” in the operating section of our condensed consolidated statements of cash flows. Sale of assets In March 2019, we completed the sale of an individual property previously classified as held for sale in our Production & Automation Technologies segment. Net proceeds of $2.1 million were received upon the close of the transaction, resulting in a gain that was not material to the condensed consolidated statement of income during the nine months ended September 30, 2019 . Refer to Note 6—Dispositions for information related to our sale of our pressure vessel manufacturing business in our Production & Automation Technologies segment.

Basis of Presentation and Sep_2

Basis of Presentation and Separation Change in Accounting Estimate (Policies)	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Basis of presentation	Basis of Presentation Prior to the Separation, our results of operations, financial position and cash flows were derived from the consolidated financial statements and accounting records of Dover and reflect the combined historical results of operations, financial position and cash flows of certain Dover entities conducting its upstream oil and gas energy business within Dover’s Energy segment, including an allocated portion of Dover’s corporate costs. These financial statements have been presented as if such businesses had been combined for all periods prior to the Separation. All intercompany transactions and accounts within Dover were eliminated. The assets and liabilities were reflected on a historical cost basis since all of the assets and liabilities presented were wholly owned by Dover and were transferred within the Dover consolidated group. The statements of income also include expense allocations for certain corporate functions historically performed by Dover and not allocated to its operating segments, including corporate executive management, human resources, information technology, facilities, tax, shared services, finance and legal, including the costs of salaries, benefits and other related costs. These expense allocations were based on direct usage or benefit where identifiable, with the remainder allocated on the basis of revenue, headcount or other measures. These pre-Separation combined financial statements may not include all of the actual expenses that would have been incurred had we been a stand-alone public company during the periods presented prior to the Separation and consequently may not reflect our results of operations, financial position and cash flows had we been a stand-alone public company during the periods presented prior to the Separation. Actual costs that would have been incurred if we had been a stand-alone public company would depend on a variety of factors, including organizational structure and strategic decisions made in various areas, including information technology and infrastructure. Prior to the Separation, transactions between Apergy and Dover, with the exception of transactions discussed in Note 3— Related Party Transactions , are reflected in the condensed consolidated statements of cash flows as a financing activity in “Distributions to Dover Corporation, net.” Intercompany notes payable to Dover prior to the Separation were not settled in cash. Accordingly, no interest expense related to intercompany debt was presented in the condensed consolidated statements of income for the period presented prior to the Separation. See Note 3—Related Party Transactions for additional information. All financial information presented after the Separation represents the consolidated results of operations, financial position and cash flows of Apergy. Accordingly, our results of operations and cash flows consist of the consolidated results of Apergy during the periods ended September 30, 2019 and for the period from May 9, 2018 to September 30, 2018, and the combined results of operations and cash flows for the periods prior to May 9, 2018. Our balance sheets as of September 30, 2019 and December 31, 2018, reflect the consolidated balances of Apergy. Our management believes the assumptions underlying these condensed consolidated financial statements, including the assumptions regarding the allocation of corporate expenses from Dover for periods prior to the Separation, are reasonable. The legal transfer of the oil and gas energy businesses from Dover to Apergy occurred on May 9, 2018; however, for ease of reference, and unless otherwise stated or the context otherwise requires, all references to “Apergy Corporation,” “Apergy,” “we,” “us” or “our” refer (i) prior to the Separation, to the Apergy businesses, consisting of entities, assets and liabilities conducting the oil and gas business within Dover’s Energy segment and (ii) after the Separation, to Apergy Corporation and its consolidated subsidiaries. Interim Financial Information The accompanying unaudited condensed consolidated financial statements of Apergy have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission pertaining to interim financial information. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP have been condensed or omitted. Therefore, these financial statements should be read in conjunction with the audited consolidated financial statements, and notes thereto, which are included in our Annual Report on Form 10-K for the year ended December 31, 2018. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Although these estimates are based on management’s best knowledge of current events and actions that we may undertake in the future, actual results may differ from our estimates. In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments (consisting of normal recurring adjustments unless otherwise specified) necessary for a fair statement of our financial condition and results of operations as of and for the periods presented. Revenue, expenses, assets and liabilities can vary during each quarter of the year. Therefore, the results and trends in these financial statements may not be representative of the results that may be expected for the year ending December 31, 2019.
Use of Estimates	The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Although these estimates are based on management’s best knowledge of current events and actions that we may undertake in the future, actual results may differ from our estimates. In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments (consisting of normal recurring adjustments unless otherwise specified) necessary for a fair statement of our financial condition and results of operations as of and for the periods presented. Revenue, expenses, assets and liabilities can vary during each quarter of the year. Therefore, the results and trends in these financial statements may not be representative of the results that may be expected for the year ending December 31, 2019. Change in Accounting Estimate Effective January 1, 2019, we changed our estimate of the useful lives for certain equipment used within our leased asset program in our Production & Automation Technologies segment to better reflect the estimated periods in which the assets will remain in service. The estimated useful lives of the equipment, previously estimated at three years, was increased to five years. The effect of this change in estimate for the three months ended September 30, 2019 , was a reduction in depreciation expense of $2.5 million , an increase in net income of $1.9 million , and an increase in basic and diluted earnings per share of $0.02 per share. The effect of this change in estimate for the nine months ended September 30, 2019 , was a reduction in depreciation expense of $6.5 million , an increase in net income of $4.9 million , and an increase in basic and diluted earnings per share of $0.06 per share.
Reclassifications	Revisions, Reclassifications and Other Adjustments We revised our previously issued financial statements for the nine months ended September 30, 2018 , for the presentation of capital leases in the condensed consolidated statement of cash flow. The effect of the revisions was an increase of $0.2 million to cash provided by operating activities, a $3.0 million decrease to cash required by investing activities and a $3.2 million increase to cash required by financing activities. Certain prior-year amounts have been reclassified to conform to the current presentation. We recorded out-of-period adjustments primarily related to inventory and leased assets write-offs during the three months ended September 30, 2019 which increased revenue by $0.6 million , increased cost of goods and services by $2.6 million and decreased net income by $1.5 million . Management determined the errors were not material to the previously issued condensed consolidated interim financial statements as of and for the three months ended March 31, 2019 and the three and six months ended June 30, 2019. In addition, the correction of the errors in the three months ended September 30, 2019 was not material.

New Accounting Standards New Ac

New Accounting Standards New Accounting Standards (Policies)	9 Months Ended
	Sep. 30, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recently Adopted and Issued Accounting Standards	Recently Adopted Accounting Standards Effective January 1, 2019, we adopted Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2016-02, “ Leases (Topic 842). ” This update requires a lessee to recognize in the statement of financial position a right-of-use asset representing its right to use the underlying asset for the lease term and a liability for future lease payments. Similar to past guidance, the update continues to differentiate between finance leases and operating leases; however, this distinction now primarily relates to differences in the manner of expense recognition over time and in the classification of lease payments in the statement of cash flows. Additionally, lessors will be required to classify leases as sales-type, finance or operating, with classification affecting the pattern of income recognition. Classification for both lessees and lessors is now based on an assessment of whether a lease contract is economically similar to the purchase of a non-financial asset from the perspective of control. The update also requires quantitative and qualitative disclosures to enable users to understand the amount, timing, and judgments related to leases and the related cash flows. We applied the provisions of this ASU to our lease contracts as of January 1, 2019, using the modified retrospective method of adoption. Prior period amounts have not been adjusted and continue to be reflected in accordance with our historical accounting policies. As of January 1, 2019, we recorded operating lease right-of-use assets of $27.0 million , operating lease liabilities of $28.7 million , and a reduction to retained earnings of $1.7 million as a result of the adoption of this guidance. We have applied the following practical expedients and elections under the new standard: • We elected to utilize the package of transition practical expedients, which among other things, allowed us to carry forward our historical lease classifications for existing leases. • For contracts in which we are a lessee, we have elected to account for each lease component and its associated non-lease components as a single lease component. • We elected to utilize the short term lease exemption for lease contracts with a term of less than 12 months. These contracts are excluded from the measurement of our right-of-use assets and lease liabilities and are recognized in earnings on a straight-line basis over their lease term. • We elected to utilize the practical expedient to exclude sales tax from the measurement of lease revenue. Lessee accounting —Lease liabilities are measured at the lease commencement date and are based on the present value of remaining payments contractually required under the contract. Payments that are variable in nature are excluded from the measurement of our lease liabilities and are recorded as an expense as incurred. Options to renew or extend a lease are included in the measurement of our lease liabilities only when it is reasonably certain that we will exercise these rights. In estimating the present value of our lease liabilities, payments are discounted at our incremental borrowing rate (“IBR”), which has been applied utilizing a portfolio approach. We utilized information publicly available from companies within our industry with similar credit profiles to construct a company-specific yield curve in order to estimate the rate of interest we would pay to borrow at various lease terms. At lease commencement, we recognize a lease right-of-use asset equal to our lease liability, adjusted for lease payments paid to the lessor prior to the lease commencement date, and any initial direct costs incurred. Operating lease expense is recorded on a straight-line basis over the lease term. For finance leases, we amortize our right-of-use assets on a straight-line basis over the shorter of the asset’s useful life or the lease term. Additionally, interest expense is recognized each period related to the accretion of our lease liabilities over their respective lease terms. Lessor accounting —Our lease arrangements generally allow customers to rent equipment on a daily basis with no stated end date. Customers may return the equipment at any point subsequent to the lease commencement date without penalty. We account for these arrangements as a daily renewal option beginning on the lease commencement date, with the lease term determined as the period in which it is reasonably certain the option will be exercised. Based on our assessment of the lease classification criteria, our lease arrangements have been classified as operating leases. Our lease arrangements generally include lease and non-lease components for which revenue is recognized based on each component’s standalone price. Lease revenue is recognized on a straight-line basis over the term of the lease and is included in “Other revenue” in the condensed consolidated statement of income. Non-lease revenue related to our lease arrangements is recognized in accordance with our revenue recognition accounting policy. Assets in our lease program are reported in “Property, plant, and equipment, net” on our condensed consolidated balance sheets and are depreciated over their estimated useful lives to an estimated salvage value. Leased equipment damaged in operation is generally charged to the customer. Charges for damaged leased equipment is recorded as “Product revenue” and the remaining net book value of the leased asset is expensed as “Costs of goods and services” in the condensed consolidated statements of income. See Note 13—Leases for additional information related to our lease accounting. See Note 20—Cash Flow Information for additional information regarding the presentation of our leases within our condensed consolidated statements of cash flows. Effective July 1, 2019, we adopted ASU 2018-15, “ Intangibles—Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. ” The amendments in this update align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by the amendments in this update. The amendments in this update have been applied prospectively to all implementation costs incurred after the date of adoption. The impact of adopting the new standard was not material to our financial statements for the three months ended September 30, 2019 . Recently Issued Accounting Standards In June 2016, the FASB issued ASU 2016-13, “ Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments .” The update amends the impairment model to utilize an expected loss methodology in place of the currently used incurred loss methodology, which may result in earlier recognition of losses related to financial instruments. The guidance will be effective for us on January 1, 2020. Early adoption is permitted for annual periods beginning after December 15, 2018. We do not expect the adoption of this ASU to have a material impact on our financial statements. In August 2018, the FASB issued ASU 2018-14, “ Compensation—Retirement Benefits—Defined Benefit Plans—General (Subtopic 715-20): Disclosure Framework—Changes to the Disclosure Requirements for Defined Benefit Plans.” The amendment modifies certain disclosure requirements for defined benefit plans. Among other requirements and modifications, the amendment requires an explanation of the reasons for significant gains and losses related to changes in the benefit obligation for the period. The guidance will be effective for us with our annual filing for the year ended December 31, 2020. We do not expect the adoption of this ASU to have a material impact on our financial statements.

Earnings per Share (Tables)

Earnings per Share (Tables)	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Schedule of earnings per share, basic and diluted	A reconciliation of the number of shares used for the basic and diluted earnings per share calculation was as follows: Three Months Ended September 30, Nine Months Ended September 30, (in thousands, except per share data) 2019 2018 2019 2018 Net income attributable to Apergy $ 10,225 $ 25,264 $ 56,291 $ 71,470 Weighted-average number of shares outstanding 77,460 77,340 77,416 77,340 Dilutive effect of stock-based compensation 113 229 199 402 Total shares and dilutive securities 77,573 77,569 77,615 77,742 Basic earnings per share attributable to Apergy $ 0.13 $ 0.33 $ 0.73 $ 0.92 Diluted earnings per share attributable to Apergy $ 0.13 $ 0.33 $ 0.73 $ 0.92

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2019
Business Combinations [Abstract]
Schedule of Consideration Transferred [Table Text Block]	The acquisition-date fair value of the consideration transferred consisted of the following: (in thousands) Cash $ 12,500 Contingent consideration (1) 1,500 Total consideration transferred $ 14,000 _______________________ (1) Contingent consideration is payable to the seller based on the acquired business exceeding a revenue target over an eighteen month period ending January 2021. Achievement of the revenue target is considered probable.
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	The following table summarizes the final fair values of the assets acquired at the acquisition date: (in thousands) Inventory $ 1,840 Customer relationships 2,650 Technology - Technical know-how 4,000 Goodwill 5,510 Total assets acquired $ 14,000

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Sep. 30, 2019
Inventory, Net [Abstract]
Components of Inventory	Inventories consisted of the following: (in thousands) September 30, 2019 December 31, 2018 Raw materials $ 49,752 $ 52,057 Work in progress 14,603 11,416 Finished goods 179,548 180,624 243,903 244,097 LIFO and valuation adjustments (24,289 ) (25,778 ) Inventories, net $ 219,614 $ 218,319

Goodwill (Tables)

Goodwill (Tables)	9 Months Ended
	Sep. 30, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	The carrying amount of goodwill, including changes therein, by reporting segment was as follows: (in thousands) Production & Automation Technologies Drilling Technologies Total December 31, 2018 $ 803,849 $ 101,136 $ 904,985 Acquisition 5,510 — 5,510 Foreign currency translation 198 — 198 September 30, 2019 $ 809,557 $ 101,136 $ 910,693

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2019
Debt Disclosure [Abstract]
Schedule of Debt	Long-term debt consisted of the following: (in thousands) September 30, 2019 December 31, 2018 Revolving credit facility $ — $ — Term loan facility 295,000 370,000 6.375% Senior Notes due 2026 300,000 300,000 Finance lease obligations 3,706 7,485 Total 598,706 677,485 Net unamortized discounts and issuance costs (10,126 ) (11,377 ) Total long-term debt $ 588,580 $ 666,108

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2019
Class of Stock [Line Items]
Schedule of Stock by Class	The following is a summary of our capital stock activity: (in thousands) Common Stock March 31, 2018 — Issuance of common stock 77,340 June 30, 2018 77,340 Shares issued—share-based compensation 1 September 30, 2018 77,341 (in thousands) Common Stock December 31, 2018 77,353 Shares issued—share-based compensation 39 March 31, 2019 77,392 Shares issued—share-based compensation 67 June 30, 2019 77,459 Shares issued—share-based compensation 1 September 30, 2019 77,460
Schedule of Accumulated Other Comprehensive Loss	Accumulated other comprehensive loss consisted of the following: (in thousands) Foreign Currency Translation Defined Pension and Other Post-Retirement Benefits Accumulated Other Comprehensive Loss December 31, 2017 $ (21,936 ) $ (4,480 ) $ (26,416 ) Reclassification adjustment for cumulative effect of change in accounting principle — (1,315 ) (1,315 ) Other comprehensive loss before reclassifications, net of tax (1,691 ) — (1,691 ) Reclassification adjustment for net losses included in net income, net of tax — 49 49 Other comprehensive income (loss), net of tax (1,691 ) 49 (1,642 ) March 31, 2018 (23,627 ) (5,746 ) (29,373 ) Net transfer from Dover — (1,450 ) (1,450 ) Other comprehensive income (loss) before reclassifications, net of tax (6,874 ) 170 (6,704 ) Reclassification adjustment for net losses included in net income, net of tax — 46 46 Other comprehensive income (loss), net of tax (6,874 ) 216 (6,658 ) June 30, 2018 (30,501 ) (6,980 ) (37,481 ) Net transfer from Dover — (970 ) (970 ) Other comprehensive loss before reclassifications, net of tax (515 ) — (515 ) Reclassification adjustment for net losses included in net income, net of tax — 439 439 Other comprehensive income (loss), net of tax (515 ) 439 (76 ) September 30, 2018 $ (31,016 ) $ (7,511 ) $ (38,527 ) (in thousands) Foreign Currency Translation Defined Pension and Other Post-Retirement Benefits Accumulated Other Comprehensive Loss December 31, 2018 $ (36,146 ) $ (6,760 ) $ (42,906 ) Other comprehensive income (loss) before reclassifications, net of tax 1,090 (323 ) 767 Reclassification adjustment for net losses included in net income, net of tax — 422 422 Other comprehensive income, net of tax 1,090 99 1,189 March 31, 2019 (35,056 ) (6,661 ) (41,717 ) Other comprehensive income before reclassifications, net of tax 974 — 974 Reclassification adjustment for net losses included in net income, net of tax — 68 68 Other comprehensive income, net of tax 974 68 1,042 June 30, 2019 (34,082 ) (6,593 ) (40,675 ) Other comprehensive loss before reclassifications, net of tax (2,900 ) — (2,900 ) Reclassification adjustment for net losses included in net income, net of tax — 68 68 Other comprehensive income (loss), net of tax (2,900 ) 68 (2,832 ) September 30, 2019 $ (36,982 ) $ (6,525 ) $ (43,507 )
Reclassifications from accumulated other comprehensive loss	Reclassification adjustments from accumulated other comprehensive loss to net income related to defined pension and other post-retirement benefits consisted of the following: Three Months Ended September 30, Nine Months Ended September 30, Affected line items on the condensed consolidated statements of income (in thousands) 2019 2018 2019 2018 Amortization of actuarial loss and other (1) $ 91 $ 116 $ 274 $ 242 Other (income) expense, net Settlement loss (1) — 484 486 484 Other (income) expense, net Total before tax 91 600 760 726 Income before income taxes Tax benefit (23 ) (161 ) (202 ) (192 ) Provision for income taxes $ 68 $ 439 $ 558 $ 534 Net income _______________________ (1) These accumulated other comprehensive loss components are included in the computation of net periodic benefit cost (See Note 15—Employee Benefit Plans for additional information).

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 30, 2019
Revenue from Contract with Customer [Abstract]
Schedule of Disaggregation of Revenue	Revenue disaggregated by revenue type was as follows: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2019 2018 2019 2018 Product revenue $ 244,651 $ 283,102 $ 787,698 $ 807,949 Service revenue 20,708 20,471 62,056 62,014 Lease and other revenue 13,022 12,895 36,372 35,481 Total revenue $ 278,381 $ 316,468 $ 886,126 $ 905,444 Revenue disaggregated by end market in each of our reporting segments was as follows: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2019 2018 2019 2018 Drilling Technologies $ 54,878 $ 75,254 $ 202,764 $ 209,727 Production & Automation Technologies: Artificial lift 176,253 187,872 531,127 543,302 Digital products 34,460 31,248 100,056 86,761 Other production equipment 13,245 22,380 53,083 66,444 Intra-segment eliminations (455 ) (286 ) (904 ) (790 ) 223,503 241,214 683,362 695,717 Total revenue $ 278,381 $ 316,468 $ 886,126 $ 905,444 Revenue disaggregated by geography was as follows: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2019 2018 2019 2018 United States $ 210,905 $ 252,747 $ 680,396 $ 712,499 Canada 19,224 20,759 54,009 58,639 Middle East 16,317 13,645 44,360 40,091 Europe 10,468 7,625 40,518 27,805 Latin America 6,835 8,364 23,936 25,097 Australia 8,002 8,939 22,009 24,951 Asia-Pacific and other 6,630 4,389 20,898 16,362 Total revenue $ 278,381 $ 316,468 $ 886,126 $ 905,444
Schedule of Contract Balances	Contract assets and contract liabilities from contracts with customers were as follows: (in thousands) September 30, 2019 December 31, 2018 Contract assets $ 2,044 $ 4,571 Contract liabilities - current 6,798 5,863

Leases - Balance Sheet (Tables)

Leases - Balance Sheet (Tables)	9 Months Ended
	Sep. 30, 2019
Leases Statement of Financial Position [Abstract]
Lessee Statement of Financial Position [Table Text Block]	Leases are presented in our condensed consolidated balance sheet as follows: (in thousands) Balance Sheet Classification September 30, 2019 Right-of Use Assets: Finance leases Property, plant, and equipment, net $ 8,115 Operating leases Other non-current assets 21,604 Total lease right-of-use assets 29,719 Lease Liabilities: Finance leases - current Accrued expenses and other current liabilities 4,336 Finance leases Long-term debt 3,706 Operating leases - current Accrued expenses and other current liabilities 7,709 Operating leases Other long-term liabilities 16,758 Total lease liabilities $ 32,509

Leases - Lease Cost (Tables)

Leases - Lease Cost (Tables)	9 Months Ended
	Sep. 30, 2019
Leases [Abstract]
Lease, Cost [Table Text Block]	Components of total lease cost were as follows: (in thousands) Three Months Ended September 30, 2019 Nine Months Ended September 30, 2019 Finance lease cost: Amortization of right-of-use assets $ 1,041 $ 3,717 Interest on lease liabilities 60 293 Operating lease cost 2,302 8,140 Short-term lease cost 1,331 3,253 Variable lease cost 145 707 Sublease income (133 ) (367 ) Total net lease cost $ 4,746 $ 15,743 Lease term and discount rate —Our weighted-average remaining lease term and weighted-average discount rate for operating and finance leases are as follows: September 30, 2019 Weighted-average remaining lease term (years): Operating lease 4.6 Finance lease 2.0 Weighted-average discount rate: Operating lease 6.6 % Finance lease 5.2 %

Leases - Maturity Analysis (Tab

Leases - Maturity Analysis (Tables)	9 Months Ended
	Sep. 30, 2019
Leases [Abstract]
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	Future minimum payments on our operating and finance leases as of September 30, 2019 are as follows: (in thousands) Operating Finance 2019 $ 2,482 $ 1,509 2020 7,823 4,114 2021 4,646 2,368 2022 3,934 420 2023 3,471 77 Thereafter 7,017 2 Total future minimum lease payments 29,373 8,490 Interest included within lease payments (4,906 ) (448 ) Total lease liabilities $ 24,467 $ 8,042
Finance Lease, Liability, Maturity [Table Text Block]	Future minimum payments on our operating and finance leases as of September 30, 2019 are as follows: (in thousands) Operating Finance 2019 $ 2,482 $ 1,509 2020 7,823 4,114 2021 4,646 2,368 2022 3,934 420 2023 3,471 77 Thereafter 7,017 2 Total future minimum lease payments 29,373 8,490 Interest included within lease payments (4,906 ) (448 ) Total lease liabilities $ 24,467 $ 8,042

Leases - Lease Assets (Tables)

Leases - Lease Assets (Tables)	9 Months Ended
	Sep. 30, 2019
Assets Leased to Others [Member]
Lease assets [Table Text Block]	Components of our leased assets are as follows: (in thousands) September 30, 2019 Property, plant, and equipment $ 170,889 Accumulated depreciation (69,993 ) Property, plant, and equipment, net $ 100,896

Equity and Cash Incentive Pro_2

Equity and Cash Incentive Program - Stock-based compensation expense (Tables)	9 Months Ended
	Sep. 30, 2019
Share-based Payment Arrangement, Noncash Expense [Abstract]
Schedule of Stock-Based Compensation Expense	Stock-based compensation expense relating to all stock-based incentive plans was as follows: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2019 2018 2019 2018 Stock-based compensation expense $ 2,524 $ 1,768 $ 7,545 $ 3,129 Tax benefit (615 ) (421 ) (1,841 ) (717 ) Stock-based compensation expense, net of tax $ 1,909 $ 1,347 $ 5,704 $ 2,412

Equity and Cash Incentive Pro_3

Equity and Cash Incentive Program - Activity Rollforward (Tables)	9 Months Ended
	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Outstanding Award, Activity, Excluding Option [Table Text Block]	A summary of activity relating to our share-based awards for the nine months ended September 30, 2019 , is as follows: (in shares) Stock-Settled Appreciation Rights Performance Share Awards Restricted Stock Units Outstanding at January 1, 2019 477,950 86,817 414,840 Granted — 92,919 155,777 Forfeited (7,030 ) (5,010 ) (16,032 ) Exercised / Vested (46,125 ) — (141,437 ) Outstanding at September 30, 2019 424,795 174,726 413,148

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2019
Segment Reporting [Abstract]
Segment revenue and operating profit	Segment revenue and segment operating profit were as follows: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2019 2018 2019 2018 Segment revenue: Production & Automation Technologies $ 223,503 $ 241,214 $ 683,362 $ 695,717 Drilling Technologies 54,878 75,254 202,764 209,727 Total revenue $ 278,381 $ 316,468 $ 886,126 $ 905,444 Income before income taxes: Segment operating profit: Production & Automation Technologies $ 17,329 $ 24,175 $ 54,411 $ 57,272 Drilling Technologies 13,796 26,209 64,853 71,738 Total segment operating profit 31,125 50,384 119,264 129,010 Corporate expense and other (1) 8,110 6,581 16,686 16,273 Interest expense, net 9,537 10,584 30,068 16,813 Income before income taxes $ 13,478 $ 33,219 $ 72,510 $ 95,924 _______________________ (1) Corporate expense and other includes costs not directly attributable or allocated to our reporting segments such as corporate executive management and other administrative functions, costs related to our Separation from Dover and the results attributable to our noncontrolling interest.

Condensed Consolidating Finan_2

Condensed Consolidating Financial Statements Condensed Consolidating Financial Information (Tables)	9 Months Ended
	Sep. 30, 2019
Condensed Financial Statements, Captions [Line Items]
Condensed Income Statement [Table Text Block]	Three Months Ended September 30, 2019 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Product revenue $ — $ 211,988 $ 32,663 $ — $ 244,651 Other revenue — 31,664 14,278 (12,212 ) 33,730 Total revenue — 243,652 46,941 (12,212 ) 278,381 Cost of goods and services — 162,031 36,979 (12,148 ) 186,862 Gross profit — 81,621 9,962 (64 ) 91,519 Selling, general and administrative expense 64 62,289 6,460 — 68,813 Interest expense, net 9,502 32 3 — 9,537 Other (income) expense, net — (1,011 ) 702 — (309 ) Income (loss) before income taxes and equity in earnings of affiliates (9,566 ) 20,311 2,797 (64 ) 13,478 Provision for (benefit from) income taxes (2,180 ) 2,181 3,072 (14 ) 3,059 Income (loss) before equity in earnings of affiliates (7,386 ) 18,130 (275 ) (50 ) 10,419 Equity in earnings of affiliates 17,611 5,926 5,841 (29,378 ) — Net income 10,225 24,056 5,566 (29,428 ) 10,419 Net income attributable to noncontrolling interest — — 194 — 194 Net income attributable to Apergy $ 10,225 $ 24,056 $ 5,372 $ (29,428 ) $ 10,225 Comprehensive income attributable to Apergy $ 7,393 $ 23,079 $ 3,501 $ (26,580 ) $ 7,393 Three Months Ended September 30, 2018 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Product revenue $ — $ 250,549 $ 32,553 $ — $ 283,102 Other revenue — 32,230 11,933 (10,797 ) 33,366 Total revenue — 282,779 44,486 (10,797 ) 316,468 Cost of goods and services — 175,718 37,899 (10,883 ) 202,734 Gross profit — 107,061 6,587 86 113,734 Selling, general and administrative expense 86 63,659 5,461 — 69,206 Interest expense, net 10,492 84 9 (1 ) 10,584 Other (income) expense, net — (711 ) 1,435 1 725 Income (loss) before income taxes and equity in earnings of affiliates (10,578 ) 44,029 (318 ) 86 33,219 Provision for (benefit from) income taxes (2,574 ) 8,743 1,536 18 7,723 Income (loss) before equity in earnings of affiliates (8,004 ) 35,286 (1,854 ) 68 25,496 Equity in earnings of affiliates 33,268 5,347 12,604 (51,219 ) — Net income 25,264 40,633 10,750 (51,151 ) 25,496 Net income attributable to noncontrolling interest — — 232 — 232 Net income attributable to Apergy $ 25,264 $ 40,633 $ 10,518 $ (51,151 ) $ 25,264 Comprehensive income attributable to Apergy $ 25,188 $ 39,903 $ 11,171 $ (51,074 ) $ 25,188 Nine Months Ended September 30, 2019 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Product revenue $ — $ 700,014 $ 87,684 $ — $ 787,698 Other revenue — 90,801 39,751 (32,124 ) 98,428 Total revenue — 790,815 127,435 (32,124 ) 886,126 Cost of goods and services — 505,375 106,122 (32,208 ) 579,289 Gross profit — 285,440 21,313 84 306,837 Selling, general and administrative expense 207 182,867 17,716 — 200,790 Interest expense, net 29,791 256 21 — 30,068 Other expense, net — 1,952 1,517 — 3,469 Income (loss) before income taxes and equity in earnings of affiliates (29,998 ) 100,365 2,059 84 72,510 Provision for (benefit from) income taxes (6,918 ) 21,122 1,450 18 15,672 Income (loss) before equity in earnings of affiliates (23,080 ) 79,243 609 66 56,838 Equity in earnings of affiliates 79,371 14,974 18,015 (112,360 ) — Net income 56,291 94,217 18,624 (112,294 ) 56,838 Net income attributable to noncontrolling interest — — 547 — 547 Net income attributable to Apergy $ 56,291 $ 94,217 $ 18,077 $ (112,294 ) $ 56,291 Comprehensive income attributable to Apergy $ 55,690 $ 93,750 $ 17,932 $ (111,682 ) $ 55,690 Nine Months Ended September 30, 2018 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Product revenue $ — $ 713,865 $ 94,084 $ — $ 807,949 Other revenue — 95,284 34,374 (32,163 ) 97,495 Total revenue — 809,149 128,458 (32,163 ) 905,444 Cost of goods and services — 514,816 111,142 (31,542 ) 594,416 Gross profit — 294,333 17,316 (621 ) 311,028 Selling, general and administrative expense 1,588 176,539 16,247 — 194,374 Interest expense, net 16,494 288 32 (1 ) 16,813 Other expense, net — 2,065 1,851 1 3,917 Income (loss) before income taxes and equity in earnings of affiliates (18,082 ) 115,441 (814 ) (621 ) 95,924 Provision for (benefit from) income taxes (4,217 ) 23,911 4,595 (130 ) 24,159 Income (loss) before equity in earnings of affiliates (13,865 ) 91,530 (5,409 ) (491 ) 71,765 Equity in earnings of affiliates 85,335 18,292 37,049 (140,676 ) — Net income 71,470 109,822 31,640 (141,167 ) 71,765 Net income attributable to noncontrolling interest — — 295 — 295 Net income attributable to Apergy $ 71,470 $ 109,822 $ 31,345 $ (141,167 ) $ 71,470 Comprehensive income attributable to Apergy $ 63,094 $ 109,177 $ 23,614 $ (132,791 ) $ 63,094
Condensed Balance Sheet [Table Text Block]	September 30, 2019 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Assets Cash and cash equivalents $ 108 $ 29,041 $ 11,478 $ — $ 40,627 Receivables, net 394 206,521 38,300 (8,834 ) 236,381 Inventories, net — 188,555 32,609 (1,550 ) 219,614 Prepaid expenses and other current assets 78 29,793 4,645 — 34,516 Total current assets 580 453,910 87,032 (10,384 ) 531,138 Property, plant and equipment, net — 237,649 11,736 — 249,385 Goodwill — 633,771 276,922 — 910,693 Advances due from affiliates 536,389 20,230 88,035 (644,654 ) — Investment in subsidiaries 1,096,182 713,088 563,185 (2,372,455 ) — Intangible assets, net — 171,259 80,152 — 251,411 Other non-current assets 3,304 19,011 7,311 — 29,626 Total assets 1,636,455 2,248,918 1,114,373 (3,027,493 ) 1,972,253 Liabilities and Equity Accounts payable 24 102,808 20,187 (8,834 ) 114,185 Accrued compensation and employee benefits — 34,301 6,115 — 40,416 Accrued expenses and other current liabilities 9,750 33,536 10,116 (1,550 ) 51,852 Total current liabilities 9,774 170,645 36,418 (10,384 ) 206,453 Advances due to affiliates — 624,424 20,230 (644,654 ) — Long-term debt 584,875 3,586 119 — 588,580 Deferred income taxes — 80,735 16,853 — 97,588 Other long-term liabilities — 32,277 5,549 — 37,826 Total liabilities 594,649 911,667 79,169 (655,038 ) 930,447 Equity Total stockholders’ equity 1,041,806 1,337,251 1,032,199 (2,372,455 ) 1,038,801 Noncontrolling interest — — 3,005 — 3,005 Total equity 1,041,806 1,337,251 1,035,204 (2,372,455 ) 1,041,806 Total liabilities and equity $ 1,636,455 $ 2,248,918 $ 1,114,373 $ (3,027,493 ) $ 1,972,253 December 31, 2018 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Assets Cash and cash equivalents $ 108 $ 27,533 $ 14,191 $ — $ 41,832 Receivables, net 1,743 230,230 35,019 (17,044 ) 249,948 Inventories, net — 189,015 30,936 (1,632 ) 218,319 Prepaid expenses and other current assets 24,583 17,064 3,106 (24,542 ) 20,211 Total current assets 26,434 463,842 83,252 (43,218 ) 530,310 Property, plant and equipment, net — 231,373 12,955 — 244,328 Goodwill — 633,771 271,214 — 904,985 Advances due from affiliates 600,802 14,185 82,889 (697,876 ) — Investment in subsidiaries 1,013,869 687,691 545,298 (2,246,858 ) — Intangible assets, net — 198,531 85,157 — 283,688 Other non-current assets 3,996 2,371 2,078 — 8,445 Total assets 1,645,101 2,231,764 1,082,843 (2,987,952 ) 1,971,756 Liabilities and Equity Accounts payable 22 114,745 33,335 (17,044 ) 131,058 Accrued compensation and employee benefits — 35,278 5,268 — 40,546 Accrued expenses and other current liabilities 4,929 46,722 4,914 (26,174 ) 30,391 Total current liabilities 4,951 196,745 43,517 (43,218 ) 201,995 Advances due to affiliates — 683,700 14,176 (697,876 ) — Long-term debt 658,623 7,363 122 — 666,108 Deferred income taxes — 81,296 20,428 — 101,724 Other long-term liabilities — 19,441 961 — 20,402 Total liabilities 663,574 988,545 79,204 (741,094 ) 990,229 Equity Total stockholders’ equity 981,527 1,243,219 1,001,181 (2,246,858 ) 979,069 Noncontrolling interest — — 2,458 — 2,458 Total equity 981,527 1,243,219 1,003,639 (2,246,858 ) 981,527 Total liabilities and equity $ 1,645,101 $ 2,231,764 $ 1,082,843 $ (2,987,952 ) $ 1,971,756
Condensed Cash Flow Statement [Table Text Block]	Nine Months Ended September 30, 2019 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Cash provided (required) by operating activities $ (36,254 ) $ 161,085 $ (1,441 ) $ — $ 123,390 Cash provided (required) by investing activities: Capital expenditures — (30,387 ) (1,202 ) — (31,589 ) Proceeds from sale of fixed assets — 2,935 19 — 2,954 Payment on sale of business — (2,194 ) — — (2,194 ) Payment on acquisition — (12,500 ) — — (12,500 ) Net cash required by investing activities — (42,146 ) (1,183 ) — (43,329 ) Cash provided (required) by financing activities: Proceeds from long-term debt 36,500 — — — 36,500 Repayment of long-term debt (111,500 ) — — — (111,500 ) Advances due to (from) affiliates 111,254 (111,573 ) 319 — — Payments of finance lease obligations — (4,070 ) (38 ) — (4,108 ) Payments related to taxes withheld on stock-based compensation — (1,788 ) (53 ) — (1,841 ) Net cash provided (required) by financing activities 36,254 (117,431 ) 228 — (80,949 ) Effect of exchange rate changes on cash and cash equivalents — — (317 ) — (317 ) Net increase (decrease) in cash and cash equivalents — 1,508 (2,713 ) — (1,205 ) Cash and cash equivalents at beginning of period 108 27,533 14,191 — 41,832 Cash and cash equivalents at end of period $ 108 $ 29,041 $ 11,478 $ — $ 40,627 Nine Months Ended September 30, 2018 (in thousands) Apergy Corporation Subsidiary Guarantors Subsidiary Non-guarantors Adjustments and eliminations Total Cash provided (required) by operating activities $ (16,694 ) $ 104,136 $ 6,588 $ (999 ) $ 93,031 Cash provided (required) by investing activities: Capital expenditures — (40,797 ) (2,086 ) — (42,883 ) Proceeds from sale of fixed assets — 938 32 — 970 Purchase price adjustments on acquisition — — 53 — 53 Net cash required by investing activities — (39,859 ) (2,001 ) — (41,860 ) Cash provided (required) by financing activities: Proceeds from long-term debt, net of discounts 713,963 — — — 713,963 Payment of debt issue costs (16,006 ) — — — (16,006 ) Repayment of long-term debt (20,000 ) — — — (20,000 ) Advances due to (from) affiliates (660,836 ) 677,999 (17,163 ) — — Distributions to Dover Corporation, net (319 ) (736,557 ) 7,020 999 (728,857 ) Distribution to noncontrolling interest — — (2,720 ) — (2,720 ) Payments of finance lease obligations — (3,174 ) — — (3,174 ) Net cash provided (required) by financing activities 16,802 (61,732 ) (12,863 ) 999 (56,794 ) Effect of exchange rate changes on cash and cash equivalents — — (75 ) — (75 ) Net increase (decrease) in cash and cash equivalents 108 2,545 (8,351 ) — (5,698 ) Cash and cash equivalents at beginning of period — 5,763 17,949 — 23,712 Cash and cash equivalents at end of period $ 108 $ 8,308 $ 9,598 $ — $ 18,014

Cash Flow Information (Tables)

Cash Flow Information (Tables)	9 Months Ended
	Sep. 30, 2019
Supplemental Cash Flow Elements [Abstract]
Schedule of Cash Flow, Supplemental Disclosures [Table Text Block]	Supplemental cash flow information is as follows: (in thousands) Statement of Cash Flows Classification Nine Months Ended September 30, 2019 Cash information: Cash required by operating leases (1) Operating $ 8,955 Cash required by finance leases - interest Operating 295 Cash required by finance leases - principal Financing 4,108 Non-cash information: Operating lease additions (2) Non-cash $ 34,961 Finance lease additions Non-cash 3,990 _______________________ (1) Cash required by operating leases is reported net of operating lease expense in the operating section of our condensed consolidated statements of cash flows in “Accrued expenses and other liabilities.” (2) Operating lease additions include lease liabilities recognized at the time of adoption. Refer to Note 2—New Accounting Standards for additional information.

Basis of Presentation and Sep_3

Basis of Presentation and Separation - Separation and Distribution (Details)	May 09, 2018shares
Debt Instrument [Line Items]
Number of companies separated	2
Common stock issued (in shares)	77,339,828

Basis of Presentation and Sep_4

Basis of Presentation and Separation - Change in accounting estimate (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Depreciation			$ (51,116)	$ (52,814)
Net income attributable to Apergy	$ 10,225	$ 25,264	56,291	$ 71,470
Change in service life
Depreciation	2,500		6,500
Net income attributable to Apergy	$ 1,900		$ 4,900
Earnings per share, basic and diluted	$ 0.02		$ 0.06

Basis of Presentation and Sep_5

Basis of Presentation and Separation - Revisions and restatements (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2018
Net Cash Provided by (Used in) Operating Activities		$ 123,390	$ 93,031
Net Cash Provided by (Used in) Investing Activities		(43,329)	(41,860)
Net Cash Provided by (Used in) Financing Activities		$ 80,949	56,794
Immaterial error correction - revenue	$ 600
Immaterial error correction - cost of sales	2,600
Immaterial Error Correction - net income	$ 1,500
Restatement Adjustment [Member]
Net Cash Provided by (Used in) Operating Activities			200
Net Cash Provided by (Used in) Investing Activities			3,000
Net Cash Provided by (Used in) Financing Activities			$ 3,200

New Accounting Standards New _2

New Accounting Standards New Accounting Standards (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, right-of-use asset	$ 21,604
Operating lease, liability	$ 24,467
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, right-of-use asset		$ 27,000
Operating lease, liability		28,700
Reclassification adjustment for cumulative effect of change in accounting principle		$ 1,700

Related Party Transactions (Det

Related Party Transactions (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)
Related party transaction, selling, general and administrative expenses	$ 7.4
Royalty Agreements [Member]
Related party transaction, royalty expenses	$ 2.3

Earnings per Share (Details)

Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands		May 09, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Common stock issued (in shares)		77,339,828
Net income attributable to Apergy			$ 10,225	$ 25,264	$ 56,291	$ 71,470
Weighted-average number of shares outstanding	[1]		77,460,000	77,340,000	77,416,000	77,340,000
Dilutive effect of stock-based compensation			113,000	229,000	199,000	402,000
Total shares and dilutive securities	[1]		77,573,000	77,569,000	77,615,000	77,742,000
Basic earnings per share attributable to Apergy (in dollars per share)	[1]		$ 0.13	$ 0.33	$ 0.73	$ 0.92
Diluted earnings per share attributable to Apergy (in dollars per share)	[1]		$ 0.13	$ 0.33	$ 0.73	$ 0.92
[1]	See Note 4—Earnings Per Share

Acquisitions (Details)

Acquisitions (Details) - USD ($) $ in Thousands		Jul. 31, 2019	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Business Combinations [Abstract]
Cash consideration		$ 12,500	$ 12,500	$ 0
Contingent consideration	[1]	1,500
Total consideration transferred		14,000
Acquired Finite-Lived Intangible Assets [Line Items]
Inventory		1,840
Goodwill		5,510	$ 910,693		$ 904,985
Total assets acquired		14,000
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets		2,650
Technology - Technical know-how
Acquired Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets		$ 4,000
[1]	Contingent consideration is payable to the seller based on the acquired business exceeding a revenue target over an eighteen month period ending January 2021. Achievement of the revenue target is considered probable.

Acquisitions Details - Narrativ

Acquisitions Details - Narrative (Details)	Jul. 31, 2019
Technology - Technical know-how
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	15 years
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	15 years

Dispositions (Details)

Dispositions (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Dispositions [Abstract]
Impairment of held-for-sale assets	$ 1,700
Payment on sale of business	2,194	$ 0
Loss on sale of business	$ 2,475	$ 0

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Inventory, Net [Abstract]
Raw materials	$ 49,752	$ 52,057
Work in progress	14,603	11,416
Finished goods	179,548	180,624
Subtotal	243,903	244,097
LIFO and valuation adjustments	(24,289)	(25,778)
Inventories, net	$ 219,614	$ 218,319

Goodwill (Details)

Goodwill (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Jul. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Balance	$ 910,693	$ 5,510	$ 904,985
Acquisition	5,510
Foreign currency translation	198
Balance	910,693
Production and Automation Technologies [Member]
Goodwill [Roll Forward]
Balance	809,557		803,849
Acquisition	5,510
Foreign currency translation	198
Balance	809,557
Drilling Technologies [Member]
Goodwill [Roll Forward]
Balance	101,136		$ 101,136
Balance	$ 101,136

Debt - Long-term Debt (Details)

Debt - Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Finance lease liabilities, noncurrent	$ 3,706
Capital lease obligations, noncurrent		$ 7,485
Total	598,706	677,485
Net unamortized discounts and issuance costs	(10,126)	(11,377)
Total long-term debt	588,580	666,108
Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	0	0
Term Loan Facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 295,000	$ 370,000
Senior Notes | 6.375% Senior Notes Due May 2026
Debt Instrument [Line Items]
Debt interest rate	6.375%	6.375%
Long-term debt, gross	$ 300,000	$ 300,000

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Letters of credit outstanding and surety bonds, amount	$ 13	$ 3.6
Accrued liability - environmental	2
Tax Indemnification Agreement [Member]
Loss Contingencies [Line Items]
Loss Contingency, Loss in Period	$ 3.4

Stockholders' Equity - Capital

Stockholders' Equity - Capital stock activity (Details) - shares	May 09, 2018	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2018	Mar. 31, 2018
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)		77,500,000					77,400,000
Issuance of common stock (shares)	77,339,828
Common Stock [Member]
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)		77,460,000	77,459,000	77,392,000	77,341,000	77,340,000	77,353,000	0
Issuance of common stock (shares)						77,340,000
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture		1,000	67,000	39,000	1,000

Stockholders' Equity - Accumula

Stockholders' Equity - Accumulated other comprehensive loss (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Jan. 01, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance			$ 979,069				$ 979,069
Net transfer to Dover				$ 2,118	$ (739,284)	$ (1,635)
Other comprehensive loss	$ (2,832)	$ 1,042	1,189	(76)	(6,658)	(1,642)	(601)	$ (8,376)
Ending balance	1,038,801						1,038,801
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(40,675)	(41,717)	(42,906)	(37,481)	(29,373)	(26,416)	(42,906)	(26,416)
Reclassification adjustment for cumulative effect of change in accounting principle									$ (1,315)
Net transfer to Dover				(970)	(1,450)
Other comprehensive income (loss) before reclassifications, net of tax	(2,900)	974	767	(515)	(6,704)	(1,691)
Reclassification adjustment for net losses included in net income, net of tax	68	68	422	439	46	49
Other comprehensive loss	(2,832)	1,042	1,189	(76)	(6,658)	(1,642)
Ending balance	(43,507)	(40,675)	(41,717)	(38,527)	(37,481)	(29,373)	(43,507)	(38,527)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(34,082)	(35,056)	(36,146)	(30,501)	(23,627)	(21,936)	(36,146)	(21,936)
Other comprehensive income (loss) before reclassifications, net of tax	(2,900)	974	1,090	(515)	(6,874)	(1,691)
Other comprehensive loss	(2,900)	974	1,090	(515)	(6,874)	(1,691)
Ending balance	(36,982)	(34,082)	(35,056)	(31,016)	(30,501)	(23,627)	(36,982)	(31,016)
Defined Pension and Other Post-Retirement Benefits
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(6,593)	(6,661)	(6,760)	(6,980)	(5,746)	(4,480)	(6,760)	(4,480)
Reclassification adjustment for cumulative effect of change in accounting principle									$ (1,315)
Net transfer to Dover				(970)	(1,450)
Other comprehensive income (loss) before reclassifications, net of tax			(323)		170
Reclassification adjustment for net losses included in net income, net of tax	68	68	422	439	46	49
Other comprehensive loss	68	68	99	439	216	49
Ending balance	$ (6,525)	$ (6,593)	$ (6,661)	$ (7,511)	$ (6,980)	$ (5,746)	$ (6,525)	$ (7,511)

Stockholders' Equity - Reclassi

Stockholders' Equity - Reclassifications from accumulated other comprehensive loss (Details) - USD ($) $ in Thousands		3 Months Ended						9 Months Ended
		Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other (income) expense, net		$ (309)			$ 725			$ 3,469	$ 3,917
Total before tax		(13,478)			(33,219)			(72,510)	(95,924)
Tax benefit		3,059			7,723			15,672	24,159
Net income		(10,419)	$ (23,850)	$ (22,569)	(25,496)	$ (22,075)	$ (24,194)	(56,838)	(71,765)
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) And Net Transition Including Portion Attributable to Noncontrolling Interest [Member] [Member] | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other (income) expense, net	[1]	91			116			274	242
Accumulated Defined Benefit Plans Adjustment, Settlement Gain (Loss) Including Portion Attributable to Noncontrolling Interest [Member] [Member] | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other (income) expense, net	[1]				484			486	484
Accumulated Defined Benefit Plans Adjustment Including Portion Attributable to Noncontrolling Interest [Member] | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax		91			600			760	726
Tax benefit		(23)			(161)			(202)	(192)
Net income		$ 68			$ 439			$ 558	$ 534
[1]	These accumulated other comprehensive loss components are included in the computation of net periodic benefit cost (See Note 15—Employee Benefit Plans for additional information)

Revenue - Disaggregation of Rev

Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Lease and other revenue	$ 13,022	$ 12,895	$ 36,372	$ 35,481
Revenue	278,381	316,468	886,126	905,444
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenue	210,905	252,747	680,396	712,499
CANADA
Disaggregation of Revenue [Line Items]
Revenue	19,224	20,759	54,009	58,639
Middle East [Member]
Disaggregation of Revenue [Line Items]
Revenue	16,317	13,645	44,360	40,091
Europe [Member]
Disaggregation of Revenue [Line Items]
Revenue	10,468	7,625	40,518	27,805
Latin America [Member]
Disaggregation of Revenue [Line Items]
Revenue	6,835	8,364	23,936	25,097
AUSTRALIA
Disaggregation of Revenue [Line Items]
Revenue	8,002	8,939	22,009	24,951
Asia-Pacific and other [Member]
Disaggregation of Revenue [Line Items]
Revenue	6,630	4,389	20,898	16,362
Product [Member]
Disaggregation of Revenue [Line Items]
Revenue	244,651	283,102	787,698	807,949
Service [Member]
Disaggregation of Revenue [Line Items]
Revenue	20,708	20,471	62,056	62,014
Drilling Technologies [Member]
Disaggregation of Revenue [Line Items]
Revenue	54,878	75,254	202,764	209,727
Production and Automation Technologies [Member]
Disaggregation of Revenue [Line Items]
Revenue	223,503	241,214	683,362	695,717
Production and Automation Technologies [Member] | Intra-segment eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue	(455)	(286)	(904)	(790)
Production and Automation Technologies [Member] | Artificial lift [Member]
Disaggregation of Revenue [Line Items]
Revenue	176,253	187,872	531,127	543,302
Production and Automation Technologies [Member] | Digital products [Member]
Disaggregation of Revenue [Line Items]
Revenue	34,460	31,248	100,056	86,761
Production and Automation Technologies [Member] | Other production equipment [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 13,245	$ 22,380	$ 53,083	$ 66,444

Revenue - Contract Balances (De

Revenue - Contract Balances (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Contract assets	$ 2,044	$ 4,571
Contract liabilities - current	$ 6,798	$ 5,863

Leases (Details)

Leases (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Leases [Abstract]
Operating Lease, Lease Income, Lease Payments	$ 11.6	$ 32.8

Leases - Balance Sheet (Details

Leases - Balance Sheet (Details) $ in Thousands	Sep. 30, 2019USD ($)
Leases Statement of Financial Position [Abstract]
Finance lease, right-of-use asset	$ 8,115
Operating lease, right-of-use asset	21,604
Total right-of-use assets	29,719
Finance lease, liability, current	4,336
Finance lease liabilities, noncurrent	3,706
Operating lease, liability, current	7,709
Operating lease, liability, noncurrent	16,758
Total lease liability	$ 32,509

Leases - Lease Cost (Details)

Leases - Lease Cost (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019USD ($)	Sep. 30, 2019USD ($)
Leases [Abstract]
Finance lease cost, amortization of right-of-use assets	$ 1,041	$ 3,717
Finance lease cost, Interest on lease liabilities	60	293
Operating lease cost	2,302	8,140
Short-term lease cost	1,331	3,253
Variable lease cost	145	707
Sublease income	(133)	(367)
Total net lease cost	$ 4,746	$ 15,743
Operating lease, weighted-average remaining lease term	4 years 7 months	4 years 7 months
Finance lease, weighted-average remaining lease term	2 years	2 years
Operating lease, weighted-average discount rate (as a percent)	6.60%	6.60%
Finance lease, weighted-average discount rate (as a percent)	5.20%	5.20%

Leases - Maturity Tables (Detai

Leases - Maturity Tables (Details) $ in Thousands	Sep. 30, 2019USD ($)
Leases [Abstract]
Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year	$ 2,482
Lessee, Operating Lease, Liability, Payments, Due Year Two	7,823
Lessee, Operating Lease, Liability, Payments, Due Year Three	4,646
Lessee, Operating Lease, Liability, Payments, Due Year Four	3,934
Lessee, Operating Lease, Liability, Payments, Due Year Five	3,471
Lessee, Operating Lease, Liability, Payments, Due after Year Five	7,017
Lessee, Operating Lease, Liability, Payments, Due	29,373
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	(4,906)
Operating lease, liability	24,467
Finance Lease, Liability, Payments, Remainder of Fiscal Year	1,509
Finance Lease, Liability, Payments, Due Year Two	4,114
Finance Lease, Liability, Payments, Due Year Three	2,368
Finance Lease, Liability, Payments, Due Year Four	420
Finance Lease, Liability, Payments, Due Year Five	77
Finance Lease, Liability, Payments, Due after Year Five	2
Finance Lease, Liability, Payment, Due	8,490
Finance Lease, Liability, Undiscounted Excess Amount	(448)
Finance Lease, Liability	$ 8,042

Leases - Lease Assets (Details)

Leases - Lease Assets (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Accumulated depreciation	$ (420,113)	$ (420,113)	$ (392,344)
Property, plant, and equipment, net	249,385	249,385	$ 244,328
Assets Leased to Others [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment	170,889	170,889
Accumulated depreciation	(69,993)	(69,993)
Property, plant, and equipment, net	100,896	100,896
Depreciation expense	$ 9,500	$ 27,300

Income Taxes (Details)

Income Taxes (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Effective tax rate (as a percent)	22.70%	23.20%	21.60%	25.20%

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Plan [Abstract]
Net periodic benefit cost	$ 0.4	$ 1.1	$ 1.5	$ 2.9

Equity and Cash Incentive Pro_4

Equity and Cash Incentive Program (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Stock-based compensation expense [Abstract]
Stock-based compensation expense	$ 2,524	$ 1,768	$ 7,545	$ 3,129
Tax benefit	(615)	(421)	(1,841)	(717)
Stock-based compensation expense, net of tax	$ 1,909	$ 1,347	$ 5,704	$ 2,412
Stock-Settled Appreciation Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding (in shares)	424,795		424,795		477,950
Forfeited (in shares)			(7,030)
Exercised (in shares)			(46,125)
Performance Share Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding (in shares)	174,726		174,726		86,817
Granted (in shares)			92,919
Forfeited (in shares)			(5,010)
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding (in shares)	413,148		413,148		414,840
Granted (in shares)			155,777
Forfeited (in shares)			(16,032)
Vested (in shares)			(141,437)

Fair Value Measurements (Detail

Fair Value Measurements (Details) $ in Millions	9 Months Ended
	Sep. 30, 2019USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of held-for-sale assets	$ 1.7
Contingent consideration	1.5
Senior Notes | 6.375% Senior Notes Due May 2026
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Principal amount of debt issued	300
Senior Notes | 6.375% Senior Notes Due May 2026 | Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt, fair value	300
Term Loan Facility
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Principal amount of debt issued	295
Term Loan Facility | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt, fair value	$ 295.6

Segment Information (Details)

Segment Information (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Reconciliation from Segment Totals to Consolidated [Abstract]
Revenue		$ 278,381	$ 316,468	$ 886,126	$ 905,444
Reconciliation of Earnings from Continuing Operations from Segments to Consolidated [Abstract]
Income before income taxes		13,478	33,219	72,510	95,924
Production and Automation Technologies [Member]
Reconciliation from Segment Totals to Consolidated [Abstract]
Revenue		223,503	241,214	683,362	695,717
Reconciliation of Earnings from Continuing Operations from Segments to Consolidated [Abstract]
Income before income taxes		17,329	24,175	54,411	57,272
Drilling Technologies [Member]
Reconciliation from Segment Totals to Consolidated [Abstract]
Revenue		54,878	75,254	202,764	209,727
Reconciliation of Earnings from Continuing Operations from Segments to Consolidated [Abstract]
Income before income taxes		13,796	26,209	64,853	71,738
Total segments [Member]
Reconciliation of Earnings from Continuing Operations from Segments to Consolidated [Abstract]
Income before income taxes		31,125	50,384	119,264	129,010
Corporate expense / other [Member]
Reconciliation of Earnings from Continuing Operations from Segments to Consolidated [Abstract]
Income before income taxes	[1]	(8,110)	(6,581)	(16,686)	(16,273)
Interest Expense [Member]
Reconciliation of Earnings from Continuing Operations from Segments to Consolidated [Abstract]
Income before income taxes		$ (9,537)	$ (10,584)	$ (30,068)	$ (16,813)
[1]	Corporate expense and other includes costs not directly attributable or allocated to our reporting segments such as corporate executive management and other administrative functions, costs related to our Separation from Dover and the results attributable to our noncontrolling interest.

Condensed Consolidating Finan_3

Condensed Consolidating Financial Statements Condensed Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Condensed Financial Statements, Captions [Line Items]
Total revenue	$ 278,381			$ 316,468			$ 886,126	$ 905,444
Cost of goods and services	186,862			202,734			579,289	594,416
Gross Profit	91,519			113,734			306,837	311,028
Selling, general and administrative expense	68,813			69,206			200,790	194,374
Interest expense, net	9,537			10,584			30,068	16,813
Other (income) expense, net	(309)			725			3,469	3,917
Income before income taxes	13,478			33,219			72,510	95,924
Provision for income taxes	3,059			7,723			15,672	24,159
Income (loss) before equity in earnings of affiliates	10,419			25,496			56,838	71,765
Net income	10,419	$ 23,850	$ 22,569	25,496	$ 22,075	$ 24,194	56,838	71,765
Net income attributable to noncontrolling interest	194			232			547	295
Net income attributable to Apergy	10,225			25,264			56,291	71,470
Comprehensive income attributable to Apergy	7,393			25,188			55,690	63,094
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Total revenue	(12,212)			(10,797)			(32,124)	(32,163)
Cost of goods and services	(12,148)			(10,883)			(32,208)	(31,542)
Gross Profit	(64)			86			84	(621)
Interest expense, net				(1)				(1)
Other (income) expense, net				1				1
Income before income taxes	(64)			86			84	(621)
Provision for income taxes	(14)			18			18	(130)
Income (loss) before equity in earnings of affiliates	(50)			68			66	(491)
Equity in earnings of affiliates	(29,378)			(51,219)			(112,360)	(140,676)
Net income	(29,428)			(51,151)			(112,294)	(141,167)
Net income attributable to Apergy	(29,428)			(51,151)			(112,294)	(141,167)
Comprehensive income attributable to Apergy	(26,580)			(51,074)			(111,682)	(132,791)
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Total revenue	46,941			44,486			127,435	128,458
Cost of goods and services	36,979			37,899			106,122	111,142
Gross Profit	9,962			6,587			21,313	17,316
Selling, general and administrative expense	6,460			5,461			17,716	16,247
Interest expense, net	3			9			21	32
Other (income) expense, net	702			1,435			1,517	1,851
Income before income taxes	2,797			(318)			2,059	(814)
Provision for income taxes	3,072			1,536			1,450	4,595
Income (loss) before equity in earnings of affiliates	(275)			(1,854)			609	(5,409)
Equity in earnings of affiliates	5,841			12,604			18,015	37,049
Net income	5,566			10,750			18,624	31,640
Net income attributable to noncontrolling interest	194			232			547	295
Net income attributable to Apergy	5,372			10,518			18,077	31,345
Comprehensive income attributable to Apergy	3,501			11,171			17,932	23,614
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Total revenue	243,652			282,779			790,815	809,149
Cost of goods and services	162,031			175,718			505,375	514,816
Gross Profit	81,621			107,061			285,440	294,333
Selling, general and administrative expense	62,289			63,659			182,867	176,539
Interest expense, net	32			84			256	288
Other (income) expense, net	(1,011)			(711)			1,952	2,065
Income before income taxes	20,311			44,029			100,365	115,441
Provision for income taxes	2,181			8,743			21,122	23,911
Income (loss) before equity in earnings of affiliates	18,130			35,286			79,243	91,530
Equity in earnings of affiliates	5,926			5,347			14,974	18,292
Net income	24,056			40,633			94,217	109,822
Net income attributable to Apergy	24,056			40,633			94,217	109,822
Comprehensive income attributable to Apergy	23,079			39,903			93,750	109,177
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Selling, general and administrative expense	64			86			207	1,588
Interest expense, net	9,502			10,492			29,791	16,494
Income before income taxes	(9,566)			(10,578)			(29,998)	(18,082)
Provision for income taxes	(2,180)			(2,574)			(6,918)	(4,217)
Income (loss) before equity in earnings of affiliates	(7,386)			(8,004)			(23,080)	(13,865)
Equity in earnings of affiliates	17,611			33,268			79,371	85,335
Net income	10,225			25,264			56,291	71,470
Net income attributable to Apergy	10,225			25,264			56,291	71,470
Comprehensive income attributable to Apergy	7,393			25,188			55,690	63,094
Product revenue
Condensed Financial Statements, Captions [Line Items]
Revenue	244,651			283,102			787,698	807,949
Product revenue | Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenue	32,663			32,553			87,684	94,084
Product revenue | Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenue	211,988			250,549			700,014	713,865
Other revenue
Condensed Financial Statements, Captions [Line Items]
Revenue	33,730			33,366			98,428	97,495
Other revenue | Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Revenue	(12,212)			(10,797)			(32,124)	(32,163)
Other revenue | Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenue	14,278			11,933			39,751	34,374
Other revenue | Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenue	$ 31,664			$ 32,230			$ 90,801	$ 95,284

Condensed Consolidating Finan_4

Condensed Consolidating Financial Statements Condensed Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jul. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	$ 40,627				$ 41,832	$ 18,014			$ 23,712
Receivables, net	236,381				249,948
Inventories, net	219,614				218,319
Prepaid expenses and other current assets	34,516				20,211
Total current assets	531,138				530,310
Property, plant, and equipment, net	249,385				244,328
Goodwill	910,693	$ 5,510			904,985
Intangible assets, net	251,411				283,688
Other non-current assets	29,626				8,445
Total assets	1,972,253				1,971,756
Accounts payable	114,185				131,058
Accrued compensation and employee benefits	40,416				40,546
Accrued expenses and other current liabilities	51,852				30,391
Total current liabilities	206,453				201,995
Long-term debt	588,580				666,108
Deferred income taxes	97,588				101,724
Other long-term liabilities	37,826				20,402
Total liabilities	930,447				990,229
Total stockholders’ equity	1,038,801				979,069
Noncontrolling interest	3,005				2,458
Total equity	1,041,806		$ 1,031,737	$ 1,005,203	981,527	964,762	$ 935,527	$ 1,661,302	1,640,385
Total liabilities and equity	1,972,253				1,971,756
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents
Receivables, net	(8,834)				(17,044)
Inventories, net	(1,550)				(1,632)
Prepaid expenses and other current assets					(24,542)
Total current assets	(10,384)				(43,218)
Advances due from affiliates	(644,654)				(697,876)
Investments in subsidiaries	(2,372,455)				(2,246,858)
Total assets	(3,027,493)				(2,987,952)
Accounts payable	(8,834)				(17,044)
Accrued expenses and other current liabilities	(1,550)				(26,174)
Total current liabilities	(10,384)				(43,218)
Advances due to affiliates	(644,654)				(697,876)
Total liabilities	(655,038)				(741,094)
Total stockholders’ equity	(2,372,455)				(2,246,858)
Total equity	(2,372,455)				(2,246,858)
Total liabilities and equity	(3,027,493)				(2,987,952)
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	108				108	108
Receivables, net	394				1,743
Prepaid expenses and other current assets	78				24,583
Total current assets	580				26,434
Advances due from affiliates	536,389				600,802
Investments in subsidiaries	1,096,182				1,013,869
Other non-current assets	3,304				3,996
Total assets	1,636,455				1,645,101
Accounts payable	24				22
Accrued expenses and other current liabilities	9,750				4,929
Total current liabilities	9,774				4,951
Long-term debt	584,875				658,623
Total liabilities	594,649				663,574
Total stockholders’ equity	1,041,806				981,527
Total equity	1,041,806				981,527
Total liabilities and equity	1,636,455				1,645,101
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	29,041				27,533	8,308			5,763
Receivables, net	206,521				230,230
Inventories, net	188,555				189,015
Prepaid expenses and other current assets	29,793				17,064
Total current assets	453,910				463,842
Property, plant, and equipment, net	237,649				231,373
Goodwill	633,771				633,771
Advances due from affiliates	20,230				14,185
Investments in subsidiaries	713,088				687,691
Intangible assets, net	171,259				198,531
Other non-current assets	19,011				2,371
Total assets	2,248,918				2,231,764
Accounts payable	102,808				114,745
Accrued compensation and employee benefits	34,301				35,278
Accrued expenses and other current liabilities	33,536				46,722
Total current liabilities	170,645				196,745
Advances due to affiliates	624,424				683,700
Long-term debt	3,586				7,363
Deferred income taxes	80,735				81,296
Other long-term liabilities	32,277				19,441
Total liabilities	911,667				988,545
Total stockholders’ equity	1,337,251				1,243,219
Total equity	1,337,251				1,243,219
Total liabilities and equity	2,248,918				2,231,764
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	11,478				14,191	$ 9,598			$ 17,949
Receivables, net	38,300				35,019
Inventories, net	32,609				30,936
Prepaid expenses and other current assets	4,645				3,106
Total current assets	87,032				83,252
Property, plant, and equipment, net	11,736				12,955
Goodwill	276,922				271,214
Advances due from affiliates	88,035				82,889
Investments in subsidiaries	563,185				545,298
Intangible assets, net	80,152				85,157
Other non-current assets	7,311				2,078
Total assets	1,114,373				1,082,843
Accounts payable	20,187				33,335
Accrued compensation and employee benefits	6,115				5,268
Accrued expenses and other current liabilities	10,116				4,914
Total current liabilities	36,418				43,517
Advances due to affiliates	20,230				14,176
Long-term debt	119				122
Deferred income taxes	16,853				20,428
Other long-term liabilities	5,549				961
Total liabilities	79,169				79,204
Total stockholders’ equity	1,032,199				1,001,181
Noncontrolling interest	3,005				2,458
Total equity	1,035,204				1,003,639
Total liabilities and equity	$ 1,114,373				$ 1,082,843

Condensed Consolidating Finan_5

Condensed Consolidating Financial Statements Condensed Statement of Cash Flows (Details) - USD ($) $ in Thousands	Jul. 31, 2019	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Condensed Financial Statements, Captions [Line Items]
Cash provided (required) by operating activities		$ 123,390	$ 93,031
Capital expenditures		(31,589)	(42,883)
Proceeds from sale of fixed assets		2,954	970
Payment on sale of business		(2,194)	0
Payment on acquisition	$ (12,500)	(12,500)	0
Purchase price adjustments on acquisition		0	(53)
Net cash required by investing activities		(43,329)	(41,860)
Proceeds from long-term debt, net of discounts		36,500	713,963
Payment of debt issuance costs		0	16,006
Repayment of long-term debt		(111,500)	(20,000)
Distributions to Dover Corporation, net		0	(728,857)
Distribution to noncontrolling interest		0	2,720
Payments of finance lease obligations		(4,108)	(3,174)
Payments related to taxes withheld on stock-based compensation		(1,841)	0
Net cash required by financing activities		(80,949)	(56,794)
Effect of exchange rate changes on cash and cash equivalents		(317)	(75)
Net decrease in cash and cash equivalents		(1,205)	(5,698)
Cash and cash equivalents		40,627	18,014	$ 41,832	$ 23,712
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided (required) by operating activities			(999)
Distributions to Dover Corporation, net			999
Payments related to taxes withheld on stock-based compensation		0
Net cash required by financing activities			999
Cash and cash equivalents
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided (required) by operating activities		(1,441)	6,588
Capital expenditures		(1,202)	(2,086)
Proceeds from sale of fixed assets		19	32
Purchase price adjustments on acquisition			(53)
Net cash required by investing activities		(1,183)	(2,001)
Advances due to (from) affiliates		319	(17,163)
Distributions to Dover Corporation, net			7,020
Distribution to noncontrolling interest			2,720
Payments of finance lease obligations		(38)
Payments related to taxes withheld on stock-based compensation		(53)
Net cash required by financing activities		228	(12,863)
Effect of exchange rate changes on cash and cash equivalents		(317)	(75)
Net decrease in cash and cash equivalents		(2,713)	(8,351)
Cash and cash equivalents		11,478	9,598	14,191	17,949
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided (required) by operating activities		(36,254)	(16,694)
Proceeds from long-term debt, net of discounts		36,500	713,963
Payment of debt issuance costs			16,006
Repayment of long-term debt		(111,500)	(20,000)
Advances due to (from) affiliates		111,254	(660,836)
Distributions to Dover Corporation, net			(319)
Net cash required by financing activities		36,254	16,802
Net decrease in cash and cash equivalents			108
Cash and cash equivalents		108	108	108
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided (required) by operating activities		161,085	104,136
Capital expenditures		(30,387)	(40,797)
Proceeds from sale of fixed assets		2,935	938
Payment on sale of business		(2,194)
Payment on acquisition		(12,500)
Net cash required by investing activities		(42,146)	(39,859)
Advances due to (from) affiliates		(111,573)	677,999
Distributions to Dover Corporation, net			(736,557)
Payments of finance lease obligations		(4,070)	(3,174)
Payments related to taxes withheld on stock-based compensation		(1,788)
Net cash required by financing activities		(117,431)	(61,732)
Net decrease in cash and cash equivalents		1,508	2,545
Cash and cash equivalents		$ 29,041	$ 8,308	$ 27,533	$ 5,763

Cash Flow Information Cash Flow

Cash Flow Information Cash Flow Information (Details) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018
Cash required by operating leases	[1]	$ 8,955
Cash required by finance leases - interest		295
Cash required by finance leases - principal		4,108
Operating lease additions	[2]	34,961
Finance lease additions		3,990
Transfers from inventory		61,200
Proceeds from divestiture of property held-for-sale		2,100
Assets Leased to Others [Member]
Payments to Acquire Machinery and Equipment		$ 13,900	$ 17,300
[1]	Cash required by operating leases is reported net of operating lease expense in the operating section of our condensed consolidated statements of cash flows in “Accrued expenses and other liabilities.”
[2]	Operating lease additions include lease liabilities recognized at the time of adoption. Refer to Note 2—New Accounting Standards for additional information.

Uncategorized Items - apy-20190

Label	Element	Value
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ (1,662,000)
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	(1,662,000)
AOCI Attributable to Parent [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	(1,315,000)
Net parent investment in Apergy [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 1,315,000