Core Laboratories (CLB) 10-Q 25 Oct 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Oct. 24, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	CORE LABORATORIES N V
Entity Central Index Key	1,000,229
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		44,220,731

Consolidated Balance Sheets Sta

Consolidated Balance Sheets Statement - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
CURRENT ASSETS:
Cash and cash equivalents	$ 14,100	$ 14,400
Accounts receivable, net of allowance for doubtful accounts of $2,841 and $2,590 at 2018 and 2017, respectively	143,325	133,097
Inventories	47,215	33,317
Prepaid expenses	13,308	12,592
Income taxes receivable	9,061	7,508
Other current assets	12,116	6,513
TOTAL CURRENT ASSETS	239,125	207,427
PROPERTY, PLANT AND EQUIPMENT, net	121,945	123,098
INTANGIBLES, net	9,724	9,396
GOODWILL	222,876	179,044
DEFERRED TAX ASSETS	12,977	10,719
OTHER ASSETS	59,950	55,128
TOTAL ASSETS	666,597	584,812
CURRENT LIABILITIES:
Accounts payable	41,012	41,697
Accrued payroll and related costs	25,603	28,887
Taxes other than payroll and income	6,976	7,313
Unearned revenue	15,265	12,627
Income taxes payable	2,569	825
Other current liabilities	12,084	9,227
TOTAL CURRENT LIABILITIES	103,509	100,576
LONG-TERM DEBT, net	295,745	226,989
CONTRACT LIABILITIES	2,378	4,442
DEFERRED COMPENSATION	56,819	52,786
DEFERRED TAX LIABILITIES	7,229	5,323
OTHER LONG-TERM LIABILITIES	39,505	45,964
COMMITMENTS AND CONTINGENCIES (Note 8)
Preference shares, EUR 0.02 par value; 6,000,000 shares authorized, none issued or outstanding	0	0
Common shares, EUR 0.02 par value; 200,000,000 shares authorized, 44,796,252 issued and 44,220,731 outstanding at 2018 and 44,796,252 issued and 44,184,205 outstanding at 2017	1,148	1,148
Additional paid-in capital	61,649	54,463
Retained earnings	171,617	173,855
Accumulated other comprehensive income (loss)	(7,277)	(8,353)
Treasury shares (at cost), 575,521 at 2018 and 612,047 at 2017	(69,699)	(76,269)
Total Core Laboratories N.V. shareholders' equity	157,438	144,844
Non-controlling interest	3,974	3,888
TOTAL EQUITY	161,412	148,732
TOTAL LIABILITIES AND EQUITY	$ 666,597	$ 584,812

Consolidated Balance Sheets Bal

Consolidated Balance Sheets Balance Sheet Parenthetical $ in Thousands	Sep. 30, 2018€ / shares	Sep. 30, 2018USD ($)shares	Dec. 31, 2017€ / shares	Dec. 31, 2017USD ($)shares
Statement of Financial Position [Abstract]
Allowance for doubtful accounts | $		$ 2,841		$ 2,590
Common stock, par value (euro per share) | € / shares	€ 0.02		€ 0.02
Common stock, shares authorized (in shares)		200,000,000		200,000,000
Common stock, shares issued (in shares)		44,796,252		44,796,252
Common stock, shares outstanding (in shares)		44,220,731		44,184,205
Treasury stock (in share)		575,521		612,047
Preferred stock, par value (euro per share) | € / shares	€ 0.02		€ 0.02
Preferred stock, shares authorized (in shares)		6,000,000		6,000,000
Preferred stock, shares issued (in shares)		0		0
Preferred stock, shares outstanding (in shares)		0		0

Consolidated Statements of Oper

Consolidated Statements of Operations Statement - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
REVENUE:
Services	$ 124,145	$ 117,285	$ 366,025	$ 354,827
Product sales	58,001	45,602	161,614	122,881
Total revenue	182,146	162,887	527,639	477,708
OPERATING EXPENSES:
Cost of services, exclusive of depreciation expense shown below	88,435	83,715	258,482	247,357
Cost of product sales, exclusive of depreciation expense shown below	39,744	34,646	112,788	97,659
General and administrative expense, exclusive of depreciation expense shown below	13,278	11,887	38,189	35,743
Depreciation	5,436	5,743	16,646	17,802
Amortization	244	250	720	684
Other (income) expense, net	130	(23)	170	900
OPERATING INCOME	34,879	26,669	100,644	77,563
Interest expense	3,278	2,707	9,694	8,017
Income from continuing operations before income tax expense	31,601	23,962	90,950	69,546
Income tax expense	9,404	3,595	19,697	10,233
Income from continuing operations	22,197	20,367	71,253	59,313
Income from discontinued operations, net of income taxes	208	686	(466)	2,131
Net income	22,405	21,053	70,787	61,444
Net income attributable to non-controlling interest	(7)	(33)	96	10
Net income attributable to Core Laboratories N.V.	$ 22,412	$ 21,086	$ 70,691	$ 61,434
EARNINGS PER SHARE INFORMATION:
Basic earnings per share from continuing operations (in dollar per share)	$ 0.50	$ 0.46	$ 1.61	$ 1.34
Basic earnings (loss) per share from discontinued operations (in dollar per share)	0.01	0.02	(0.01)	0.05
Basic earnings per share attributable to Core Laboratories N.V. (in dollar per share)	0.51	0.48	1.60	1.39
Diluted earnings per share from continuing operations (in dollar per share)	0.50	0.46	1.60	1.34
Diluted earnings (loss) per share from discontinued operations (in dollar per share)	0	0.02	(0.01)	0.05
Diluted earnings per share attributable to Core Laboratories N.V. (in dollar per share)	0.50	0.48	1.59	1.39
Cash dividends per share (in dollars per share)	$ 0.55	$ 0.55	$ 1.65	$ 1.65
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING:
Basic (in shares)	44,216	44,141	44,199	44,155
Diluted (in shares)	44,591	44,332	44,613	44,335

Consolidated Statement of Other

Consolidated Statement of Other Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 22,405	$ 21,053	$ 70,787	$ 61,444
Gain (loss) in fair value of interest rate swaps	205	(47)	1,086	(244)
Interest rate swap amounts reclassified to interest expense	4	112	93	419
Income taxes on derivatives	(44)	(23)	(248)	(61)
Total derivatives	165	42	931	114
Amortization to net income of prior service cost	(19)	(20)	(58)	(58)
Amortization to net income of actuarial loss	84	110	252	330
Income taxes on pension and other postretirement benefit plans	(16)	(22)	(49)	(68)
Total pension and other postretirement benefit plans	49	68	145	204
Total other comprehensive income	214	110	1,076	318
Comprehensive income	22,619	21,163	71,863	61,762
Comprehensive income (loss) attributable to non-controlling interest	(7)	(33)	96	10
Comprehensive income attributable to Core Laboratories N.V.	$ 22,626	$ 21,196	$ 71,767	$ 61,752

Consolidated Statements of Cash

Consolidated Statements of Cash Flows Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Income from continuing operations	$ 71,253	$ 59,313
Income from discontinued operations, net of income taxes	(466)	2,131
Net income	70,787	61,444
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation	18,533	17,323
Depreciation and amortization	17,366	18,486
Changes to value of life insurance policies	(3,459)	(4,541)
Deferred income taxes	(311)	3,914
Other non-cash items	1,114	(362)
Changes in assets and liabilities, net of effect of acquisitions:
Accounts receivable	(11,972)	(15,488)
Inventories	(12,121)	(796)
Prepaid expenses and other current assets	(935)	(1,545)
Other assets	(451)	1,960
Accounts payable	(2,571)	2,307
Accrued expenses	(1,452)	(10,676)
Unearned revenues	742	(1,393)
Other long-term liabilities	(1,344)	7,722
Net cash provided by operating activities	73,926	78,355
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(16,063)	(14,264)
Patents and other intangibles	(970)	(282)
Business acquisitions, net of cash acquired	47,314	0
Proceeds from sale of assets	270	643
Premiums on life insurance	(788)	(1,351)
Net cash used in investing activities	(64,865)	(15,254)
CASH FLOWS FROM FINANCING ACTIVITIES:
Repayment of debt borrowings	(80,000)	(89,000)
Proceeds from debt borrowings	150,000	106,000
Debt financing costs	(1,645)	0
Non-controlling interest - dividend	(10)	(27)
Dividends paid	(72,929)	(72,861)
Repurchase of common shares	(4,777)	(8,197)
Net cash used in financing activities	(9,361)	(64,085)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(300)	(984)
CASH AND CASH EQUIVALENTS, beginning of period	14,400	14,764
CASH AND CASH EQUIVALENTS, end of period	$ 14,100	$ 13,780

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	BASIS OF PRESENTATION The accompanying unaudited consolidated financial statements include the accounts of Core Laboratories N.V. and its subsidiaries for which we have a controlling voting interest and/or a controlling financial interest. These financial statements have been prepared in accordance with United States ("U.S.") generally accepted accounting principles ("GAAP") for interim financial information using the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, these financial statements do not include all of the information and footnote disclosures required by U.S. GAAP and should be read in conjunction with the audited financial statements and the summary of significant accounting policies and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2017 (the " 2017 Annual Report"). Core Laboratories N.V. uses the equity method of accounting for investments in which it has less than a majority interest and over which it does not exercise control but does exert significant influence. We use the cost method to record certain other investments in which we own less than 20% of the outstanding equity and do not exercise control or exert significant influence. Non-controlling interests have been recorded to reflect outside ownership attributable to consolidated subsidiaries that are less than 100% owned. In the opinion of management, all adjustments considered necessary for a fair statement of the results for the interim periods presented have been included in these financial statements. Furthermore, the operating results presented for the three and nine months ended September 30, 2018 may not necessarily be indicative of the results that may be expected for the year ending December 31, 2018 . Core Laboratories N.V.'s balance sheet information for the year ended December 31, 2017 was derived from the 2017 audited consolidated financial statements but does not include all disclosures in accordance with U.S. GAAP. References to "Core Lab", the "Company", "we", "our" and similar phrases are used throughout this Quarterly Report on Form 10-Q and relate collectively to Core Laboratories N.V. and its consolidated subsidiaries. We operate our business in two reportable segments. These complementary segments provide different services and products and utilize different technologies for improving reservoir performance and increasing oil and gas recovery from new and existing fields. • Reservoir Description: Encompasses the characterization of petroleum reservoir rock, fluid and gas samples to increase production and improve recovery of oil and gas from our clients' reservoirs. We provide laboratory based analytical and field services to characterize properties of crude oil and petroleum products to the oil and gas industry. We also provide proprietary and joint industry studies based on these types of analysis. • Production Enhancement: Includes services and products relating to reservoir well completions, perforations, stimulations and production. We provide integrated diagnostic services to evaluate and monitor the effectiveness of well completions and to develop solutions aimed at increasing the effectiveness of enhanced oil recovery projects. Certain reclassifications were made to prior period amounts in order to conform to the current period presentation. These reclassifications had no impact on the reported net income or cash flows for the three and nine months ended September 30, 2017 .

Inventories

Inventories	9 Months Ended
	Sep. 30, 2018
Inventory Disclosure [Abstract]
Inventories	INVENTORIES Inventories consisted of the following (in thousands): September 30, December 31, Finished goods $ 27,067 $ 21,668 Parts and materials 13,058 10,613 Work in progress 7,090 1,036 Total inventories $ 47,215 $ 33,317 We include freight costs incurred for shipping inventory to our clients in the Cost of product sales caption in the accompanying Consolidated Statements of Operations.

Significant Accounting Policies

Significant Accounting Policies Update	9 Months Ended
	Sep. 30, 2018
Accounting Changes and Error Corrections [Abstract]
Significant Accounting Policies Update	SIGNIFICANT ACCOUNTING POLICIES UPDATE Our significant accounting policies are detailed in "Note 1: Summary of Significant Accounting Policies" of our Annual Report on Form 10-K for the year ended December 31, 2017 . Significant changes to our accounting policies as a result of adopting Topic 606 - Revenue From Contracts with Customers are discussed below: Revenue Recognition All of our revenue is derived from contracts with clients and is reported as revenue in the Consolidated Statements of Operations. Our contracts generally include standard commercial payment terms generally acceptable in each region, and do not include financing with extended payment terms. We have no significant obligations for refunds, warranties, or similar obligations. Our revenue does not include taxes collected from our customers. In certain circumstances we apply the guidance in Accounting Standards Codification Topic 606 - Revenue From Contracts with Customers ("Topic 606") to a portfolio of contracts with similar characteristics. We use estimates and assumptions when accounting for a portfolio that reflect the size and composition of the portfolio of contracts. A performance obligation is a promise in a contract to transfer a distinct service or good to a client, and is the unit of account under Topic 606. We have contracts with two general groups of performance obligations: those that require us to perform analysis and/or diagnostic tests in our laboratory or at the client's wellsite and those from the sale of tools, diagnostic and equipment products and related services. We recognize revenue at an amount that reflects the consideration expected to be received in exchange for such services or goods as described below by applying the five-step method to: (1) identify the contract(s) with clients; (2) identify the performance obligation(s) in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligation(s) in the contract; and (5) recognize revenue when (or as) we satisfy the performance obligation(s). Services Revenue : We provide a variety of services to clients in the oil and gas industry. Where services are provided related to the testing and analysis of rock and fluids, we recognize revenue upon the provision of the test results or analysis to the client. For our design, field engineering and completion diagnostic services, we recognize revenue upon the delivery of those services at the well site or delivery of diagnostic data. In the case of our consortia studies, we have multiple performance obligations and revenue is recognized at the point in time when the testing and analysis results on each contributed core are made available to our consortia members. We conduct testing and provide analysis services in support of our consortia studies recognizing revenue as the testing and analysis results are made available to our consortia members. Product Sales Revenue : We manufacture equipment that we sell to our clients in the oil and gas industry. Revenue is recognized when title to that equipment passes to the client, which is typically when the product is shipped to the client or picked up by the client at our facilities, as set out in the contract. For arrangements that include multiple performance obligations, we allocate revenue to each performance obligation based on estimates of the price that we would charge the client for each promised service or product if it were sold on a standalone basis. To a lesser extent in all of our business segments, we enter into other types of contracts including service arrangements and non-subscription software and licensing agreements. We recognize revenue for these arrangements over time or at a point in time depending on our evaluation of when the client obtains control of the promised services or products. Contract Assets and Liabilities Contract assets and liabilities result due to the timing of revenue recognition, billings and cash collections. Contract assets include our right to payment for goods and services already transferred to a customer when the right to payment is conditional on something other than the passage of time, for example contracts where we recognize revenue over time but do not have a contractual right to payment until we complete the performance obligations. Contract assets are included in our accounts receivable and are not material as of September 30, 2018 . Contract liabilities consist of advance payments received and billings in excess of revenue recognized. We generally receive up-front payments relating to our consortia studies; we recognize revenue over the life of the study as the testing and analysis results are made available to our consortia members. We record billings in excess of revenue recognized for contracts with a duration less than twelve months as unearned revenue. We classify contract liabilities for contracts with a duration greater than twelve months as current or non-current based on the timing of when we expect to recognize revenue. The current portion of contract liabilities is included in unearned revenue and the non-current portion of contract liabilities is included in long-term contract liabilities in our consolidated balance sheet. The total balance of our contract liabilities at September 30, 2018 and December 31, 2017 was $7.2 million and $6.7 million , respectively. Disaggregation of Revenue We contract with clients for service revenue and/or product sales revenue. We present revenue disaggregated by services and product sales in our Consolidated Statements of Operations. For revenue disaggregated by reportable segment, please see Note 16 , Segment Reporting .

Contract Assets and Contract Li

Contract Assets and Contract Liabilities	9 Months Ended
	Sep. 30, 2018
Revenue from Contract with Customer [Abstract]
Contract Assets and Contract Liabilities	CONTRACT ASSETS AND CONTRACT LIABILITIES The balance of contract assets and contract liabilities consisted of the following (in thousands): September 30, 2018 December 31, 2017 Contract assets Current $ 679 $ 325 Non-Current 245 — $ 924 $ 325 Contract Liabilities Current $ 4,843 $ 2,252 Non-current 2,378 4,442 $ 7,221 $ 6,694 September 30, 2018 Estimate of when contract liabilities will be recognized within 12 months $ 4,843 within 12 to 24 months 1,994 greater than 24 months 384 We did not recognize any impairment losses on our receivables and contract assets for the three and nine months ended September 30, 2018 .

Acquisitions Acquisitions

Acquisitions Acquisitions	9 Months Ended
	Sep. 30, 2018
Business Combinations [Abstract]
Acquistions	ACQUISITIONS In September 2018, we acquired a business providing downhole technologies associated with perforating systems for $49.1 million in cash. These downhole technologies will significantly enhance Core Lab's Production Enhancement operations and its ability to bring new and innovative product offerings to our clients. We have accounted for this acquisition by allocating the purchase price to the net assets acquired based on their estimated fair values at the date of acquisition which resulted in an increase to goodwill of $44.8 million . We have not finalized the assessment of the fair values of assets acquired and liabilities assumed; estimates of certain assets and liabilities require significant judgments and assumptions, and our estimates of acquisition date fair value will be determined upon finalization of our analysis. The fair value estimates are subject to adjustment during the measurement period subsequent to the acquisition date, not to exceed one year. The acquisition is included in the Production Enhancement business segment. Acquisition-related costs totaling $0.7 million that were incurred and expensed in the third quarter of 2018 are included in Other expenses. These costs consisted of various advisory fees, and other direct incremental costs. The acquisition of this business did not have a material impact on our Consolidated Balance Sheet or Consolidated Statements of Operations.

Discontinued Operations

Discontinued Operations	9 Months Ended
	Sep. 30, 2018
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	DISCONTINUED OPERATIONS In the first quarter of 2018, in a continuing effort to streamline our business and align our business strategy for further integration of services and products, the Company committed to divest the business of our full range of permanent downhole monitoring systems and related services, which had been part of our Production Enhancement segment. We anticipate the sale of this business line will occur by the end of the first quarter of 2019. The associated results of operations are separately reported as Discontinued Operations for all periods presented on the Consolidated Statements of Operations. Balance sheet items for this discontinued business, including an allocation of goodwill from the Production Enhancement segment, have been reclassified to Other current assets and Other current liabilities in the Consolidated Balance Sheet. Cash flows from this discontinued business are shown in the table below. As such, the results from continuing operations for the Company and segment highlights for Production Enhancement, exclude these discontinued operations. Selected data for this discontinued business consisted of the following (in thousands): Three Months Ended September 30, 2018 September 30, 2017 Service revenue $ 167 $ 265 Sales revenue 2,058 3,095 Total revenue 2,225 3,360 Cost of services, exclusive of depreciation expense shown below 87 91 Cost of product sales, exclusive of depreciation expense shown below 1,944 2,438 Depreciation and Amortization 14 98 Other Expense (1 ) (74 ) Operating Income 181 807 Income tax expense (benefit) (27 ) 121 Income (loss) from discontinued operations, net of income taxes $ 208 $ 686 Nine Months Ended September 30, 2018 September 30, 2017 Service revenue $ 1,069 $ 898 Sales revenue 3,768 9,351 Total revenue 4,837 10,249 Cost of services, exclusive of depreciation expense shown below 961 482 Cost of product sales, exclusive of depreciation expense shown below 4,124 7,082 Depreciation and Amortization 115 334 Other Expense (income) 22 (148 ) Operating Income (loss) (385 ) 2,499 Income tax expense 81 368 Income (loss) from discontinued operations, net of income taxes $ (466 ) $ 2,131 September 30, 2018 December 31, 2017 Current assets $ 3,262 $ 2,549 Non-current assets 1,847 1,048 Total assets $ 5,109 $ 3,597 Current liabilities $ 740 $ 221 Non-current liabilities 77 75 Total liabilities $ 817 $ 296 Net cash provided by (used in) operating activities of discontinued operations for the three and nine months ended September 30, 2018 was $(0.8) million and $(0.5) million , respectively.

Long-Term Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2018
Debt and Capital Lease Obligations [Abstract]
Long-Term Debt	LONG-TERM DEBT We have no capital lease obligations. Long-term debt is as follows (in thousands): September 30, December 31, Senior notes $ 150,000 $ 150,000 Credit facility 148,000 78,000 Total long-term debt 298,000 228,000 Less: Debt issuance costs (2,255 ) (1,011 ) Long-term debt, net $ 295,745 $ 226,989 We have two series of senior notes outstanding with an aggregate principal amount of $150 million ("Senior Notes") issued in a private placement transaction. Series A consists of $75 million in aggregate principal amount of notes that bear interest at a fixed rate of 4.01% and are due in full on September 30, 2021 . Series B consists of $75 million in aggregate principal amount of notes that bear interest at a fixed rate of 4.11% and are due in full on September 30, 2023 . Interest on each series of the Senior Notes is payable semi-annually on March 30 and September 30. On June 19, 2018, we entered into an agreement to amend our revolving credit facility ("Credit Facility"). To appropriately size the facility, the aggregate borrowing commitment has been reduced from $400 million to $300 million . The Credit Facility provides an option to increase the commitment under the Credit Facility by an additional $100 million to bring the total borrowings available to $400 million if certain prescribed conditions are met by the Company. The Credit Facility bears interest at variable rates from LIBOR plus 1.375% to a maximum of LIBOR plus 2.00% . Any outstanding balance under the Credit Facility is due June 19, 2023 , when the Credit Facility matures. Our available capacity at any point in time is reduced by borrowings outstanding at the time and outstanding letters of credit which totaled $16.5 million at September 30, 2018 , resulting in an available borrowing capacity under the Credit Facility of $135.5 million . In addition to those items under the Credit Facility, we had $13.9 million of outstanding letters of credit and performance guarantees and bonds from other sources as of September 30, 2018 . The terms of the Credit Facility, which remained substantially the same, and Senior Notes require us to meet certain covenants, including, but not limited to, an interest coverage ratio (consolidated EBITDA divided by interest expense) and a leverage ratio (consolidated net indebtedness divided by consolidated EBITDA), where consolidated EBITDA (as defined in each agreement) and interest expense are calculated using the most recent four fiscal quarters. The Credit Facility has the more restrictive covenants with a minimum interest coverage ratio of 3.0 to 1.0 and a maximum leverage ratio of 2.5 to 1.0. We believe that we are in compliance with all such covenants contained in our credit agreements. Certain of our material, wholly-owned subsidiaries are guarantors or co-borrowers under the Credit Facility and Senior Notes. In 2014, we entered into two interest rate swap agreements for a total notional amount of $50 million . See Note 14 - Derivative Instruments and Hedging Activities . The estimated fair value of total debt at September 30, 2018 and December 31, 2017 approximated the book value of total debt. The fair value was estimated using Level 2 inputs by calculating the sum of the discounted future interest and principal payments through the date of maturity.

Pensions

Pensions	9 Months Ended
	Sep. 30, 2018
Retirement Benefits [Abstract]
Pensions	PENSION Defined Benefit Plan We provide a noncontributory defined benefit pension plan covering substantially all of our Dutch employees ("Dutch Plan") who were hired prior to 2007. The pension benefit is based on years of service and final pay or career average pay, depending on when the employee began participating. The benefits earned by the employees are immediately vested. The following table summarizes the components of net periodic pension cost under the Dutch Plan (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Service cost $ 359 $ 401 $ 1,100 $ 1,142 Interest cost 308 295 944 838 Expected return on plan assets (266 ) (249 ) (815 ) (709 ) Amortization of prior service cost (19 ) (20 ) (58 ) (58 ) Amortization of actuarial loss 84 110 252 330 Net periodic pension cost $ 466 $ 537 $ 1,423 $ 1,543 Upon adoption of ASU 2017-07 ("Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost") on January 1, 2018, the service cost component of net periodic pension cost is included in cost of sales and cost of services; the interest cost component of net periodic pension cost is included in the line item "interest expense" in the income statement and all other components of net periodic pension cost are included in the line item "other (income) expense, net" in the income statement. During the nine months ended September 30, 2018 , we contributed $1.3 million to fund the estimated 2018 premiums on investment contracts held by the Dutch Plan.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES We have been and may from time to time be named as a defendant in legal actions that arise in the ordinary course of business. These include, but are not limited to, employment-related claims and contractual disputes or claims for personal injury or property damage which occur in connection with the provision of our services and products. Management does not currently believe that any of our pending contractual, employment-related, personal injury or property damage claims and disputes will have a material effect on our future results of operations, financial position or cash flow.

Equity

Equity	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Equity	EQUITY During the three and nine months ended September 30, 2018 , we repurchased 6,736 and 42,994 of our common shares for $0.8 million and $4.8 million , respectively. These included rights to 6,736 and 22,994 shares valued at $0.8 million and $2.5 million , respectively, which were surrendered to us pursuant to the terms of a stock-based compensation plan in consideration of the participants' tax burdens that may result from the issuance of common shares under that plan. Such common shares, unless canceled, may be reissued for a variety of purposes such as future acquisitions, non-employee director stock awards or employee stock awards. We distributed 23,931 and 79,520 treasury shares upon vesting of stock-based awards during the three and nine months ended September 30, 2018 , respectively. In February, May and August 2018 , we paid a quarterly dividend of $0.55 per share of common stock. In addition, on October 9, 2018 , we declared a quarterly dividend of $0.55 per share of common stock for shareholders of record on October 19, 2018 and payable on November 20, 2018 . The following table summarizes our changes in equity for the nine months ended September 30, 2018 (in thousands): Common Shares Additional Paid-In Capital Retained Earnings Accumulated Treasury Stock Non-Controlling Interest Total Equity December 31, 2017 $ 1,148 $ 54,463 $ 173,855 $ (8,353 ) $ (76,269 ) $ 3,888 $ 148,732 Stock based-awards — 7,186 — — 11,347 — 18,533 Repurchase of common shares — — — — (4,777 ) — (4,777 ) Dividends paid — — (72,929 ) — — — (72,929 ) Non-controlling interest additions — — — — — (10 ) (10 ) Amortization of deferred pension costs, net of tax — — — 145 — — 145 Interest rate swaps, net of tax — — — 931 — — 931 Net income — — 70,691 — — 96 70,787 September 30, 2018 $ 1,148 $ 61,649 $ 171,617 $ (7,277 ) $ (69,699 ) $ 3,974 $ 161,412 Accumulated other comprehensive income (loss) consisted of the following (in thousands): September 30, December 31, Prior service cost $ 497 $ 541 Unrecognized net actuarial loss (8,514 ) (8,703 ) Fair value of derivatives, net of tax 740 (191 ) Total accumulated other comprehensive income (loss) $ (7,277 ) $ (8,353 )

Earnings per Share

Earnings per Share	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Earnings per Share	EARNINGS PER SHARE We compute basic earnings per common share by dividing net income attributable to Core Laboratories N.V. by the weighted average number of common shares outstanding during the period. Diluted earnings per common and potential common shares include additional shares in the weighted average share calculations associated with the incremental effect of dilutive restricted stock awards and contingently issuable shares, as determined using the treasury stock method. The following table summarizes the calculation of weighted average common shares outstanding used in the computation of diluted earnings per share (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Weighted average basic common shares outstanding 44,216 44,141 44,199 44,155 Effect of dilutive securities: Performance shares 221 159 269 148 Restricted stock 154 32 145 32 Weighted average diluted common and potential common shares outstanding 44,591 44,332 44,613 44,335

Other (Income) Expense, Net

Other (Income) Expense, Net	9 Months Ended
	Sep. 30, 2018
Other Income and Expenses [Abstract]
Other (Income) Expense, Net	OTHER (INCOME) EXPENSE, NET The components of other (income) expense, net, were as follows (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Sale of assets $ (136 ) $ (12 ) $ (643 ) $ (314 ) Results of non-consolidated subsidiaries (57 ) (112 ) (126 ) (287 ) Foreign exchange 1,135 139 2,221 707 Rents and royalties (264 ) (99 ) (500 ) (329 ) Return on pension assets and other pension costs (201 ) (159 ) (621 ) (437 ) Severance, compensation and other charges — — — 1,145 Acquisition-related costs 623 — 623 — Other, net (970 ) 220 (784 ) 415 Total other (income) expense, net $ 130 $ (23 ) $ 170 $ 900 Foreign exchange gains and losses are summarized in the following table (in thousands): Three Months Ended Nine Months Ended September 30, September 30, (Gains) losses by currency 2018 2017 2018 2017 Angolan Kwanza $ 33 $ (2 ) $ 194 $ (6 ) Australian Dollar 50 (13 ) 161 — British Pound 89 (27 ) 65 (82 ) Canadian Dollar (113 ) (119 ) 244 (82 ) Euro 108 431 92 1,266 Indonesian Rupiah 206 54 384 29 Turkish Lira 172 (7 ) 300 — Other currencies, net 590 (178 ) 781 (418 ) Total loss, net $ 1,135 $ 139 $ 2,221 $ 707

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	9 Months Ended
	Sep. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES We are exposed to market risks related to fluctuations in interest rates. To mitigate these risks, we utilize derivative instruments in the form of interest rate swaps. We do not enter into derivative transactions for speculative purposes. Interest Rate Risk Our Credit Facility bears interest at variable rates from LIBOR plus 1.375% to a maximum of LIBOR plus 2.00% . As a result of two interest rate swap agreements, we are subject to interest rate risk on debt in excess of $50 million drawn on our Credit Facility. In 2014, we entered into two interest rate swap agreements for a total notional amount of $50 million to hedge changes in the variable rate interest expense on $50 million of our existing or replacement LIBOR-priced debt. Under the first swap agreement of $25 million , we have fixed the LIBOR portion of the interest rate at 1.73% through August 29, 2019 , and under the second swap agreement of $25 million , we have fixed the LIBOR portion of the interest rate at 2.5% through August 29, 2024 . Each swap is measured at fair value and recorded in our Consolidated Balance Sheet as an asset or liability. They are designated and qualify as cash flow hedging instruments and are highly effective. Unrealized losses are deferred to shareholders' equity as a component of accumulated other comprehensive gain (loss) and are recognized in income as an increase or decrease to interest expense in the period in which the related cash flows being hedged are recognized in expense. At September 30, 2018 , we had fixed rate long-term debt aggregating $200 million and variable rate long-term debt aggregating $98 million , after taking into account the effect of the swaps. The fair values of outstanding derivative instruments are as follows (in thousands): Fair Value of Derivatives September 30, 2018 December 31, 2017 Balance Sheet Classification Derivatives designated as hedges: 5 year interest rate swap $ 196 $ 70 Other long-term assets 10 year interest rate swap 561 (492 ) Other long-term assets (liabilities) $ 757 $ (422 ) The fair value of all outstanding derivatives was determined using a model with inputs that are observable in the market (Level 2) or can be derived from or corroborated by observable data. The effect of the interest rate swaps on the Consolidated Statement of Operations was as follows (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Income Statement Classification Derivatives designated as hedges: 5 year interest rate swap $ (23 ) $ 31 $ (27 ) $ 136 Increase (decrease) to interest expense 10 year interest rate swap 27 81 120 283 Increase to interest expense $ 4 $ 112 $ 93 $ 419

Income Tax Expense

Income Tax Expense	9 Months Ended
	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Tax Expense	INCOME TAX EXPENSE The effective tax rates for the three months ended September 30, 2018 and 2017 were 29.8% and 15.0% , respectively, and for the nine months ended September 30, 2018 and 2017 were 21.7% and 14.7% , respectively. Income tax expense of $9.4 million in the third quarter of 2018 increased by $5.8 million compared to $3.6 million in the same period in 2017 , due to the result of several items discrete to each quarter, along with changes in activity levels in jurisdictions with differing tax rates.

Financial Instruments

Financial Instruments	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Financial Instruments	FINANCIAL INSTRUMENTS The Company's only financial assets and liabilities which are measured at fair value on a recurring basis relate to certain aspects of the Company's benefit plans and our derivative instruments. We use the market approach to value certain assets and liabilities at fair value using significant other observable inputs (Level 2) with the assistance of a third-party specialist. We do not have any assets or liabilities measured at fair value on a recurring basis using quoted prices in an active market (Level 1) or significant unobservable inputs (Level 3). Gains and losses related to the fair value changes in the deferred compensation assets and liabilities are recorded in General and administrative expense in the Consolidated Statements of Operations. Gains and losses related to the fair value of the interest rate swaps are recorded in Other comprehensive income. The following table summarizes the fair value balances (in thousands): Fair Value Measurement at September 30, 2018 Total Level 1 Level 2 Level 3 Assets: Deferred compensation assets (1) $ 49,443 $ — $ 49,443 $ — 5 year interest rate swap 196 — 196 — 10 year interest rate swap 562 — 562 — 50,201 — 50,201 — Liabilities: Deferred compensation plan $ 40,452 $ — $ 40,452 $ — $ 40,452 $ — $ 40,452 $ — Fair Value Measurement at December 31, 2017 Total Level 1 Level 2 Level 3 Assets: Deferred compensation assets (1) $ 46,145 $ — $ 46,145 $ — 5 year interest rate swap 70 — 70 — $ 46,215 $ — $ 46,215 $ — Liabilities: Deferred compensation plan $ 37,280 $ — $ 37,280 $ — 10 year interest rate swap 492 — 492 — $ 37,772 $ — $ 37,772 $ — (1) Deferred compensation assets consist of the cash surrender value of life insurance policies and are intended to assist in the funding of the deferred compensation agreements.

Segment Reporting

Segment Reporting	9 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
Segment Reporting	SEGMENT REPORTING We operate our business in two reportable segments. These complementary segments provide different services and products and utilize different technologies for improving reservoir performance and increasing oil and gas recovery from new and existing fields. • Reservoir Description: Encompasses the characterization of petroleum reservoir rock, fluid and gas samples to increase production and improve recovery of oil and gas from our clients' reservoirs. We provide laboratory based analytical and field services to characterize properties of crude oil and petroleum products to the oil and gas industry. We also provide proprietary and joint industry studies based on these types of analysis. • Production Enhancement: Includes services and products relating to reservoir well completions, perforations, stimulations and production. We provide integrated diagnostic services to evaluate and monitor the effectiveness of well completions and to develop solutions aimed at increasing the effectiveness of enhanced oil recovery projects. Results for these segments are presented below. We use the same accounting policies to prepare our segment results as are used to prepare our Consolidated Financial Statements. All interest and other non-operating income (expense) is attributable to Corporate & Other and is not allocated to specific segments. Summarized financial information concerning our segments is shown in the following table (in thousands): Reservoir Description Production Enhancement Corporate & Other 1 Consolidated Three Months Ended September 30, 2018 Revenue from unaffiliated clients $ 103,609 $ 78,537 $ — $ 182,146 Inter-segment revenue 58 141 (199 ) — Segment operating income 14,956 19,243 680 34,879 Total assets (at end of period) 321,025 276,345 69,227 666,597 Capital expenditures 2,437 1,680 31 4,148 Depreciation and amortization 4,138 1,037 505 5,680 Three Months Ended September 30, 2017 Revenue from unaffiliated clients $ 101,442 $ 61,445 $ — $ 162,887 Inter-segment revenue 54 87 (141 ) — Segment operating income (loss) 14,621 12,165 (117 ) 26,669 Total assets (at end of period) 315,346 203,413 63,985 582,744 Capital expenditures 2,930 1,605 367 4,902 Depreciation and amortization 4,383 1,092 518 5,993 Nine Months Ended September 30, 2018 Revenue from unaffiliated clients $ 306,525 $ 221,114 $ — $ 527,639 Inter-segment revenue 178 293 (471 ) — Segment operating income 44,473 55,357 814 100,644 Total assets 321,025 276,345 69,227 666,597 Capital expenditures 10,002 5,465 596 16,063 Depreciation and amortization 12,675 3,045 1,646 17,366 Nine Months Ended September 30, 2017 Revenue from unaffiliated clients $ 310,650 $ 167,058 $ — $ 477,708 Inter-segment revenue 275 537 (812 ) — Segment operating income (loss) 2 49,231 28,633 (301 ) 77,563 Total assets 315,346 203,413 63,985 582,744 Capital expenditures 7,605 5,394 1,265 14,264 Depreciation and amortization 13,531 3,398 1,557 18,486 (1) "Corporate & Other" represents those items that are not directly related to a particular segment, eliminations and the assets and liabilities of discontinued operations. (2) Reclassification of $682,000 from Corporate & Other to Production Enhancement related to general and administrative overhead costs of discontinued operations.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	9 Months Ended
	Sep. 30, 2018
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Accounting Pronouncements	RECENT ACCOUNTING PRONOUNCEMENTS Pronouncements Adopted in 2018 In May 2014, the FASB issued ASU 2014-09 ("Revenue from Contracts with Customers"), which provides guidance on revenue recognition. The core principle of this guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. This guidance requires entities to apply a five-step method to (1) identify the contract(s) with customers; (2) identify the performance obligation(s) in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligation(s) in the contract; and (5) recognize revenue when (or as) the entity satisfies a performance obligation. We adopted this standard and all related amendments on January 1, 2018. The adoption of this standard did not result in any material changes to our revenue recognition policies and procedures nor to our financial statements. Upon adoption we used the modified retrospective approach; this approach resulted in no cumulative adjustment to retained earnings or net income and no adjustments to prior periods. In March 2017, the FASB issued ASU 2017-07 ("Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost"), which requires that an employer report the service cost component of net periodic pension cost in the same line item as other compensation costs arising from services rendered by the pertinent employees during the period. The other components of net benefit cost are required to be presented in the income statement separately from the service cost component and outside a subtotal of income from operations. We adopted this standard on January 1, 2018. We used the practical expedient method which allows us to use the amounts disclosed in our pension footnote for the three and nine months ended September 30, 2017 as the estimation basis for applying the retrospective presentation requirements. The adoption of this standard did not result in any material changes to our consolidated financial statements. Pronouncements Not Yet Effective In February 2016, the FASB issued ASU 2016-02 ("Leases"), which introduces the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous guidance. The new standard establishes a right-of-use ("ROU") model that requires a lessee to record an ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. The new standard is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years with early adoption permitted. In July 2018, the FASB issued ASU 2018-11 ("Targeted Improvements to Leases"), which provides companies with an additional transition method that allows the effects of the adoption of the new standard to be recognized as a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. We are evaluating this optional transition method for adoption and anticipate the adoption of this standard will have a material impact on our Consolidated Balance Sheets, increasing both asset balances and liability balances; however, there should not be a material impact to our Consolidated Statement of Operations. In June 2016, the FASB issued ASU 2016-13 ("Measurement of Credit Losses on Financial Instruments") which replaces the incurred loss impairment methodology in current GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. The new standard is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years with early adoption permitted in fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. We are evaluating the impact that the adoption of this standard will have on our consolidated financial statements. In February 2018, the FASB issued ASU 2018-02 ("Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income"), which provides companies with an option to reclassify stranded tax effects resulting from enactment of the Tax Cuts and Jobs Act ("TCJA") from accumulated other comprehensive income to retained earnings. The new standard is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years with early adoption permitted, and would be applied either in the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the tax rate as a result of TCJA is recognized. We do not expect the adoption of this standard to have a material impact on our consolidated financial statements.

Significant Accounting Polici_2

Significant Accounting Policies Update (Policies)	9 Months Ended
	Sep. 30, 2018
Accounting Changes and Error Corrections [Abstract]
New Accounting Pronouncements	Revenue Recognition All of our revenue is derived from contracts with clients and is reported as revenue in the Consolidated Statements of Operations. Our contracts generally include standard commercial payment terms generally acceptable in each region, and do not include financing with extended payment terms. We have no significant obligations for refunds, warranties, or similar obligations. Our revenue does not include taxes collected from our customers. In certain circumstances we apply the guidance in Accounting Standards Codification Topic 606 - Revenue From Contracts with Customers ("Topic 606") to a portfolio of contracts with similar characteristics. We use estimates and assumptions when accounting for a portfolio that reflect the size and composition of the portfolio of contracts. A performance obligation is a promise in a contract to transfer a distinct service or good to a client, and is the unit of account under Topic 606. We have contracts with two general groups of performance obligations: those that require us to perform analysis and/or diagnostic tests in our laboratory or at the client's wellsite and those from the sale of tools, diagnostic and equipment products and related services. We recognize revenue at an amount that reflects the consideration expected to be received in exchange for such services or goods as described below by applying the five-step method to: (1) identify the contract(s) with clients; (2) identify the performance obligation(s) in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligation(s) in the contract; and (5) recognize revenue when (or as) we satisfy the performance obligation(s). Services Revenue : We provide a variety of services to clients in the oil and gas industry. Where services are provided related to the testing and analysis of rock and fluids, we recognize revenue upon the provision of the test results or analysis to the client. For our design, field engineering and completion diagnostic services, we recognize revenue upon the delivery of those services at the well site or delivery of diagnostic data. In the case of our consortia studies, we have multiple performance obligations and revenue is recognized at the point in time when the testing and analysis results on each contributed core are made available to our consortia members. We conduct testing and provide analysis services in support of our consortia studies recognizing revenue as the testing and analysis results are made available to our consortia members. Product Sales Revenue : We manufacture equipment that we sell to our clients in the oil and gas industry. Revenue is recognized when title to that equipment passes to the client, which is typically when the product is shipped to the client or picked up by the client at our facilities, as set out in the contract. For arrangements that include multiple performance obligations, we allocate revenue to each performance obligation based on estimates of the price that we would charge the client for each promised service or product if it were sold on a standalone basis. To a lesser extent in all of our business segments, we enter into other types of contracts including service arrangements and non-subscription software and licensing agreements. We recognize revenue for these arrangements over time or at a point in time depending on our evaluation of when the client obtains control of the promised services or products. Contract Assets and Liabilities Contract assets and liabilities result due to the timing of revenue recognition, billings and cash collections. Contract assets include our right to payment for goods and services already transferred to a customer when the right to payment is conditional on something other than the passage of time, for example contracts where we recognize revenue over time but do not have a contractual right to payment until we complete the performance obligations. Contract assets are included in our accounts receivable and are not material as of September 30, 2018 . Contract liabilities consist of advance payments received and billings in excess of revenue recognized. We generally receive up-front payments relating to our consortia studies; we recognize revenue over the life of the study as the testing and analysis results are made available to our consortia members. We record billings in excess of revenue recognized for contracts with a duration less than twelve months as unearned revenue. We classify contract liabilities for contracts with a duration greater than twelve months as current or non-current based on the timing of when we expect to recognize revenue. The current portion of contract liabilities is included in unearned revenue and the non-current portion of contract liabilities is included in long-term contract liabilities in our consolidated balance sheet. The total balance of our contract liabilities at September 30, 2018 and December 31, 2017 was $7.2 million and $6.7 million , respectively.

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Sep. 30, 2018
Inventory Disclosure [Abstract]
Schedule of Inventory, Current	Inventories consisted of the following (in thousands): September 30, December 31, Finished goods $ 27,067 $ 21,668 Parts and materials 13,058 10,613 Work in progress 7,090 1,036 Total inventories $ 47,215 $ 33,317

Contract Assets and Contract _2

Contract Assets and Contract Liabilities (Tables)	9 Months Ended
	Sep. 30, 2018
Revenue from Contract with Customer [Abstract]
Contract with Customer, Asset and Liability	The balance of contract assets and contract liabilities consisted of the following (in thousands): September 30, 2018 December 31, 2017 Contract assets Current $ 679 $ 325 Non-Current 245 — $ 924 $ 325 Contract Liabilities Current $ 4,843 $ 2,252 Non-current 2,378 4,442 $ 7,221 $ 6,694 September 30, 2018 Estimate of when contract liabilities will be recognized within 12 months $ 4,843 within 12 to 24 months 1,994 greater than 24 months 384

Discontinued Operations (Tables

Discontinued Operations (Tables)	9 Months Ended
	Sep. 30, 2018
Discontinued Operations and Disposal Groups [Abstract]
Disposal Groups, Including Discontinued Operations	Selected data for this discontinued business consisted of the following (in thousands): Three Months Ended September 30, 2018 September 30, 2017 Service revenue $ 167 $ 265 Sales revenue 2,058 3,095 Total revenue 2,225 3,360 Cost of services, exclusive of depreciation expense shown below 87 91 Cost of product sales, exclusive of depreciation expense shown below 1,944 2,438 Depreciation and Amortization 14 98 Other Expense (1 ) (74 ) Operating Income 181 807 Income tax expense (benefit) (27 ) 121 Income (loss) from discontinued operations, net of income taxes $ 208 $ 686 Nine Months Ended September 30, 2018 September 30, 2017 Service revenue $ 1,069 $ 898 Sales revenue 3,768 9,351 Total revenue 4,837 10,249 Cost of services, exclusive of depreciation expense shown below 961 482 Cost of product sales, exclusive of depreciation expense shown below 4,124 7,082 Depreciation and Amortization 115 334 Other Expense (income) 22 (148 ) Operating Income (loss) (385 ) 2,499 Income tax expense 81 368 Income (loss) from discontinued operations, net of income taxes $ (466 ) $ 2,131 September 30, 2018 December 31, 2017 Current assets $ 3,262 $ 2,549 Non-current assets 1,847 1,048 Total assets $ 5,109 $ 3,597 Current liabilities $ 740 $ 221 Non-current liabilities 77 75 Total liabilities $ 817 $ 296

Long-Term Debt (Tables)

Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2018
Debt and Capital Lease Obligations [Abstract]
Schedule of Long-term Debt Instruments	We have no capital lease obligations. Long-term debt is as follows (in thousands): September 30, December 31, Senior notes $ 150,000 $ 150,000 Credit facility 148,000 78,000 Total long-term debt 298,000 228,000 Less: Debt issuance costs (2,255 ) (1,011 ) Long-term debt, net $ 295,745 $ 226,989

Pensions (Tables)

Pensions (Tables)	9 Months Ended
	Sep. 30, 2018
Retirement Benefits [Abstract]
Schedule of Net Benefit Costs	The following table summarizes the components of net periodic pension cost under the Dutch Plan (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Service cost $ 359 $ 401 $ 1,100 $ 1,142 Interest cost 308 295 944 838 Expected return on plan assets (266 ) (249 ) (815 ) (709 ) Amortization of prior service cost (19 ) (20 ) (58 ) (58 ) Amortization of actuarial loss 84 110 252 330 Net periodic pension cost $ 466 $ 537 $ 1,423 $ 1,543

Equity (Tables)

Equity (Tables)	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Schedule of Stockholders Equity	The following table summarizes our changes in equity for the nine months ended September 30, 2018 (in thousands): Common Shares Additional Paid-In Capital Retained Earnings Accumulated Treasury Stock Non-Controlling Interest Total Equity December 31, 2017 $ 1,148 $ 54,463 $ 173,855 $ (8,353 ) $ (76,269 ) $ 3,888 $ 148,732 Stock based-awards — 7,186 — — 11,347 — 18,533 Repurchase of common shares — — — — (4,777 ) — (4,777 ) Dividends paid — — (72,929 ) — — — (72,929 ) Non-controlling interest additions — — — — — (10 ) (10 ) Amortization of deferred pension costs, net of tax — — — 145 — — 145 Interest rate swaps, net of tax — — — 931 — — 931 Net income — — 70,691 — — 96 70,787 September 30, 2018 $ 1,148 $ 61,649 $ 171,617 $ (7,277 ) $ (69,699 ) $ 3,974 $ 161,412
Schedule of Accumulated Other Comprehensive Income (Loss)	Accumulated other comprehensive income (loss) consisted of the following (in thousands): September 30, December 31, Prior service cost $ 497 $ 541 Unrecognized net actuarial loss (8,514 ) (8,703 ) Fair value of derivatives, net of tax 740 (191 ) Total accumulated other comprehensive income (loss) $ (7,277 ) $ (8,353 )

Earnings per Share (Tables)

Earnings per Share (Tables)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Schedule of Weighted Average Number of Shares	The following table summarizes the calculation of weighted average common shares outstanding used in the computation of diluted earnings per share (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Weighted average basic common shares outstanding 44,216 44,141 44,199 44,155 Effect of dilutive securities: Performance shares 221 159 269 148 Restricted stock 154 32 145 32 Weighted average diluted common and potential common shares outstanding 44,591 44,332 44,613 44,335

Other (Income) Expense, Net (Ta

Other (Income) Expense, Net (Tables)	9 Months Ended
	Sep. 30, 2018
Other Income and Expenses [Abstract]
Schedule of Other Operating Cost and Expense, by Component	The components of other (income) expense, net, were as follows (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Sale of assets $ (136 ) $ (12 ) $ (643 ) $ (314 ) Results of non-consolidated subsidiaries (57 ) (112 ) (126 ) (287 ) Foreign exchange 1,135 139 2,221 707 Rents and royalties (264 ) (99 ) (500 ) (329 ) Return on pension assets and other pension costs (201 ) (159 ) (621 ) (437 ) Severance, compensation and other charges — — — 1,145 Acquisition-related costs 623 — 623 — Other, net (970 ) 220 (784 ) 415 Total other (income) expense, net $ 130 $ (23 ) $ 170 $ 900
Schedule of Foreign Currency Gains Losses By Currency	Foreign exchange gains and losses are summarized in the following table (in thousands): Three Months Ended Nine Months Ended September 30, September 30, (Gains) losses by currency 2018 2017 2018 2017 Angolan Kwanza $ 33 $ (2 ) $ 194 $ (6 ) Australian Dollar 50 (13 ) 161 — British Pound 89 (27 ) 65 (82 ) Canadian Dollar (113 ) (119 ) 244 (82 ) Euro 108 431 92 1,266 Indonesian Rupiah 206 54 384 29 Turkish Lira 172 (7 ) 300 — Other currencies, net 590 (178 ) 781 (418 ) Total loss, net $ 1,135 $ 139 $ 2,221 $ 707

Derivative Instruments and He_2

Derivative Instruments and Hedging Activities (Tables)	9 Months Ended
	Sep. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Liabilities at Fair Value	The fair values of outstanding derivative instruments are as follows (in thousands): Fair Value of Derivatives September 30, 2018 December 31, 2017 Balance Sheet Classification Derivatives designated as hedges: 5 year interest rate swap $ 196 $ 70 Other long-term assets 10 year interest rate swap 561 (492 ) Other long-term assets (liabilities) $ 757 $ (422 )
Schedule of Derivative Instruments, Gain (Loss)	The effect of the interest rate swaps on the Consolidated Statement of Operations was as follows (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Income Statement Classification Derivatives designated as hedges: 5 year interest rate swap $ (23 ) $ 31 $ (27 ) $ 136 Increase (decrease) to interest expense 10 year interest rate swap 27 81 120 283 Increase to interest expense $ 4 $ 112 $ 93 $ 419

Financial Instruments (Tables)

Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	The following table summarizes the fair value balances (in thousands): Fair Value Measurement at September 30, 2018 Total Level 1 Level 2 Level 3 Assets: Deferred compensation assets (1) $ 49,443 $ — $ 49,443 $ — 5 year interest rate swap 196 — 196 — 10 year interest rate swap 562 — 562 — 50,201 — 50,201 — Liabilities: Deferred compensation plan $ 40,452 $ — $ 40,452 $ — $ 40,452 $ — $ 40,452 $ — Fair Value Measurement at December 31, 2017 Total Level 1 Level 2 Level 3 Assets: Deferred compensation assets (1) $ 46,145 $ — $ 46,145 $ — 5 year interest rate swap 70 — 70 — $ 46,215 $ — $ 46,215 $ — Liabilities: Deferred compensation plan $ 37,280 $ — $ 37,280 $ — 10 year interest rate swap 492 — 492 — $ 37,772 $ — $ 37,772 $ — (1) Deferred compensation assets consist of the cash surrender value of life insurance policies and are intended to assist in the funding of the deferred compensation agreements.

Segment Reporting (Tables)

Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	Summarized financial information concerning our segments is shown in the following table (in thousands): Reservoir Description Production Enhancement Corporate & Other 1 Consolidated Three Months Ended September 30, 2018 Revenue from unaffiliated clients $ 103,609 $ 78,537 $ — $ 182,146 Inter-segment revenue 58 141 (199 ) — Segment operating income 14,956 19,243 680 34,879 Total assets (at end of period) 321,025 276,345 69,227 666,597 Capital expenditures 2,437 1,680 31 4,148 Depreciation and amortization 4,138 1,037 505 5,680 Three Months Ended September 30, 2017 Revenue from unaffiliated clients $ 101,442 $ 61,445 $ — $ 162,887 Inter-segment revenue 54 87 (141 ) — Segment operating income (loss) 14,621 12,165 (117 ) 26,669 Total assets (at end of period) 315,346 203,413 63,985 582,744 Capital expenditures 2,930 1,605 367 4,902 Depreciation and amortization 4,383 1,092 518 5,993 Nine Months Ended September 30, 2018 Revenue from unaffiliated clients $ 306,525 $ 221,114 $ — $ 527,639 Inter-segment revenue 178 293 (471 ) — Segment operating income 44,473 55,357 814 100,644 Total assets 321,025 276,345 69,227 666,597 Capital expenditures 10,002 5,465 596 16,063 Depreciation and amortization 12,675 3,045 1,646 17,366 Nine Months Ended September 30, 2017 Revenue from unaffiliated clients $ 310,650 $ 167,058 $ — $ 477,708 Inter-segment revenue 275 537 (812 ) — Segment operating income (loss) 2 49,231 28,633 (301 ) 77,563 Total assets 315,346 203,413 63,985 582,744 Capital expenditures 7,605 5,394 1,265 14,264 Depreciation and amortization 13,531 3,398 1,557 18,486 (1) "Corporate & Other" represents those items that are not directly related to a particular segment, eliminations and the assets and liabilities of discontinued operations. (2) Reclassification of $682,000 from Corporate & Other to Production Enhancement related to general and administrative overhead costs of discontinued operations.

Basis of Presentation (Details)

Basis of Presentation (Details)	9 Months Ended
	Sep. 30, 2018segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of reportable segments	2

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Finished goods	$ 27,067	$ 21,668
Parts and materials	13,058	10,613
Work in progress	7,090	1,036
Total inventories	$ 47,215	$ 33,317

Significant Accounting Polici_3

Significant Accounting Policies Update (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Accounting Changes and Error Corrections [Abstract]
CONTRACT LIABILITIES	$ 7,221	$ 6,694

Contract Assets and Contract _3

Contract Assets and Contract Liabilities - Changes in Net Contract Assets (Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Contract assets, current	$ 679	$ 325
Contract assets, non-current	245	0
Contract assets	924	325
Contract liabilities, current	4,843	2,252
Contract liabilities, non-current	2,378	4,442
Contract liabilities	$ 7,221	$ 6,694

Contract Assets and Contract _4

Contract Assets and Contract Liabilities - Current and Long-term Contract Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract liabilities, current	$ 4,843	$ 2,252
Contract liabilities, non-current	2,378	$ 4,442
within 12 to 24 months
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract liabilities, non-current	1,994
greater than 24 months
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract liabilities, non-current	$ 384

Acquisitions (Details)

Acquisitions (Details) $ in Millions	1 Months Ended
	Sep. 30, 2018USD ($)
Business Acquisition [Line Items]
Consideration transferred	$ 49.1
Goodwill, acquired during period	44.8
Other expense
Business Acquisition [Line Items]
Transaction costs	$ 0.7

Discontinued Operations (Detail

Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Discontinued Operations and Disposal Groups [Abstract]
Service revenue	$ 167	$ 265	$ 1,069	$ 898
Sales revenue	2,058	3,095	3,768	9,351
Total revenue	2,225	3,360	4,837	10,249
Cost of services, exclusive of depreciation expense shown below	87	91	961	482
Cost of product sales, exclusive of depreciation expense shown below	1,944	2,438	4,124	7,082
Depreciation and Amortization	14	98	115	334
Other Expense	(1)	(74)	22	(148)
Operating Income (loss)	181	807	(385)	2,499
Income tax expense (benefit)	(27)	121	81	368
Income (loss) from discontinued operations, net of income taxes	208	$ 686	(466)	$ 2,131
Current assets	3,262		3,262		$ 2,549
Non-current assets	1,847		1,847		1,048
Total assets	5,109		5,109		3,597
Current liabilities	740		740		221
Non-current liabilities	77		77		75
Total liabilities	817		817		$ 296
Cash provided by (used in) operating activities, discontinued operations	$ (800)		$ (500)

Long-Term Debt (Details)

Long-Term Debt (Details)	Jun. 19, 2018USD ($)	Sep. 30, 2018USD ($)interest_rate_swap	Dec. 31, 2017USD ($)	Dec. 31, 2014USD ($)interest_rate_swap
Debt Instrument [Line Items]
Long-term debt		$ 298,000,000	$ 228,000,000
Less: Debt issuance costs		(2,255,000)	(1,011,000)
Long-term debt, net		295,745,000	226,989,000
Line of credit facility, prior borrowing capacity	$ 400,000,000
Line of credit facility, current borrowing capacity	300,000,000
Line of credit facility, extension capacity	100,000,000
Line of credit facility, maximum borrowing capacity	$ 400,000,000
Performance bonds under credit facility		16,500,000
Line of credit facility, remaining borrowing capacity		135,500,000
Performance bonds		$ 13,900,000
Minimum interest coverage ratio		300.00%
Maximum leverage ratio		250.00%
Number of interest rate swaps | interest_rate_swap		2		2
Senior Notes
Debt Instrument [Line Items]
Long-term debt		$ 150,000,000	150,000,000
Face amount		150,000,000
Line of Credit
Debt Instrument [Line Items]
Long-term debt		148,000,000	$ 78,000,000
Maturity date	Jun. 19, 2023
Senior Notes Series A
Debt Instrument [Line Items]
Face amount		$ 75,000,000
Interest rate, effective percentage		4.01%
Maturity date		Sep. 30, 2021
Senior Notes Series B
Debt Instrument [Line Items]
Face amount		$ 75,000,000
Interest rate, effective percentage		4.11%
Maturity date		Sep. 30, 2023
Interest Rate Swap
Debt Instrument [Line Items]
Notional amount		$ 50,000,000		$ 50,000,000
London Interbank Offered Rate (LIBOR) | Minimum
Debt Instrument [Line Items]
Derivative, basis spread on variable rate		1.375%
London Interbank Offered Rate (LIBOR) | Maximum
Debt Instrument [Line Items]
Derivative, basis spread on variable rate		2.00%

Pensions (Details)

Pensions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Retirement Benefits [Abstract]
Service cost	$ 359	$ 401	$ 1,100	$ 1,142
Interest cost	308	295	944	838
Expected return on plan assets	(266)	(249)	(815)	(709)
Amortization to net income of prior service cost	(19)	(20)	(58)	(58)
Amortization of actuarial loss	84	110	252	330
Net periodic pension cost	$ 466	$ 537	1,423	$ 1,543
Contributions by employer			$ 1,300

Equity (Narrative) (Details)

Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	Jul. 13, 2018	Aug. 31, 2018	May 31, 2018	Feb. 28, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Equity [Abstract]
Treasury stock, shares, acquired					6,736		42,994
Treasury stock, value					$ 0.8		$ 4.8
Treasury shares, acquired, tax burden					6,736		22,994
Treasury shares, acquired, value, tax burden					$ 0.8		$ 2.5
Treasury stock reissued					23,931		79,520
Cash dividends per share (in dollars per share)		$ 0.55	$ 0.55	$ 0.55	$ 0.55	$ 0.55	$ 1.65	$ 1.65
Dividends payable, date declared	Oct. 9, 2018
Dividends declared (in dollars per share)	$ 0.55
Dividends payable, date of record	Oct. 19, 2018
Dividends payable, date to be paid	Nov. 20, 2018

Equity (Details)

Equity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			$ 148,732
Stock based-awards			18,533
Repurchase of common shares			(4,777)
Dividends paid			(72,929)
Non-controlling interest additions			(10)
Amortization of deferred pension costs, net of tax			145
Interest rate swaps, net of tax			931
Net income	$ 22,405	$ 21,053	70,787	$ 61,444
Ending balance	161,412		161,412
Common Shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			1,148
Stock based-awards			0
Repurchase of common shares			0
Dividends paid			0
Non-controlling interest additions			0
Amortization of deferred pension costs, net of tax			0
Interest rate swaps, net of tax			0
Net income			0
Ending balance	1,148		1,148
Additional Paid-In Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			54,463
Stock based-awards			7,186
Repurchase of common shares			0
Dividends paid			0
Non-controlling interest additions			0
Amortization of deferred pension costs, net of tax			0
Interest rate swaps, net of tax			0
Net income			0
Ending balance	61,649		61,649
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			173,855
Stock based-awards			0
Repurchase of common shares			0
Dividends paid			(72,929)
Non-controlling interest additions			0
Amortization of deferred pension costs, net of tax			0
Interest rate swaps, net of tax			0
Net income			70,691
Ending balance	171,617		171,617
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			(8,353)
Stock based-awards			0
Repurchase of common shares			0
Dividends paid			0
Non-controlling interest additions			0
Amortization of deferred pension costs, net of tax			145
Interest rate swaps, net of tax			931
Net income			0
Ending balance	(7,277)		(7,277)
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			(76,269)
Stock based-awards			11,347
Repurchase of common shares			(4,777)
Dividends paid			0
Non-controlling interest additions			0
Amortization of deferred pension costs, net of tax			0
Interest rate swaps, net of tax			0
Net income			0
Ending balance	(69,699)		(69,699)
Non-Controlling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			3,888
Stock based-awards			0
Repurchase of common shares			0
Dividends paid			0
Non-controlling interest additions			(10)
Amortization of deferred pension costs, net of tax			0
Interest rate swaps, net of tax			0
Net income			96
Ending balance	$ 3,974		$ 3,974

Equity (Comprehensive Income) (

Equity (Comprehensive Income) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Equity [Abstract]
Prior service cost	$ 497	$ 541
Unrecognized net actuarial loss	(8,514)	(8,703)
Fair value of derivatives, net of tax	740	(191)
Total accumulated other comprehensive income (loss)	$ (7,277)	$ (8,353)

Earnings per Share (Details)

Earnings per Share (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Weighted average basic common shares outstanding	44,216	44,141	44,199	44,155
Performance shares (in shares)	221	159	269	148
Restricted stock (in shares)	154	32	145	32
Weighted average diluted common and potential common shares outstanding	44,591	44,332	44,613	44,335

Other (Income) Expense, Net (De

Other (Income) Expense, Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement Location [Line Items]
Other (income) expense, net	$ 130	$ (23)	$ 170	$ 900
Sale of assets
Income Statement Location [Line Items]
Other (income) expense, net	(136)	(12)	(643)	(314)
Results of non-consolidated subsidiaries
Income Statement Location [Line Items]
Other (income) expense, net	(57)	(112)	(126)	(287)
Foreign exchange
Income Statement Location [Line Items]
Other (income) expense, net	1,135	139	2,221	707
Rents and royalties
Income Statement Location [Line Items]
Other (income) expense, net	(264)	(99)	(500)	(329)
Return on pension assets and other pension costs
Income Statement Location [Line Items]
Other (income) expense, net	(201)	(159)	(621)	(437)
Severance, compensation and other charges
Income Statement Location [Line Items]
Other (income) expense, net	0	0	0	1,145
Acquisition-related costs
Income Statement Location [Line Items]
Other (income) expense, net	623	0	623	0
Other, net
Income Statement Location [Line Items]
Other (income) expense, net	$ (970)	$ 220	$ (784)	$ 415

Other (Income) Expense, Net (Fo

Other (Income) Expense, Net (Foreign Currency (Gain) Loss by Currency) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Foreign exchange	$ 1,135	$ 139	$ 2,221	$ 707
Angolan Kwanza
Foreign exchange	33	(2)	194	(6)
Australian Dollar
Foreign exchange	50	(13)	161	0
British Pound
Foreign exchange	89	(27)	65	(82)
Canadian Dollar
Foreign exchange	(113)	(119)	244	(82)
Euro
Foreign exchange	108	431	92	1,266
Indonesian Rupiah
Foreign exchange	206	54	384	29
Turkish Lira
Foreign exchange	172	(7)	300	0
Other currencies, net
Foreign exchange	$ 590	$ (178)	$ 781	$ (418)

Income Tax Expense (Details)

Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Effective income tax rate	29.80%	15.00%	21.70%	14.70%
Income tax expense	$ 9,404	$ 3,595	$ 19,697	$ 10,233
Change in income tax expense	$ 5,800

Derivative Instruments and He_3

Derivative Instruments and Hedging Activities (Details)	12 Months Ended
	Dec. 31, 2014USD ($)interest_rate_swap	Sep. 30, 2018USD ($)interest_rate_swap	Dec. 31, 2017USD ($)
Derivatives, Fair Value [Line Items]
Number of interest rate swaps | interest_rate_swap	2	2
Long-term debt, percentage bearing fixed interest, amount		$ 200,000,000
Long-term debt, percentage bearing variable interest, amount		98,000,000
5 year interest rate swap
Derivatives, Fair Value [Line Items]
Notional amount	$ 25,000,000
Fixed interest rate	2.50%
Maturity date	Aug. 29, 2024
Interest rate derivative assets		196,000	$ 70,000
10 year interest rate swap
Derivatives, Fair Value [Line Items]
Notional amount	$ 25,000,000
Fixed interest rate	1.73%
Maturity date	Aug. 29, 2019
Interest rate derivative assets		562,000
Interest rate derivative liabilities			(492,000)
Interest rate swap
Derivatives, Fair Value [Line Items]
Notional amount	$ 50,000,000	50,000,000
Interest rate derivative assets		757,000
Interest rate derivative liabilities			(422,000)
Level 2 | 5 year interest rate swap
Derivatives, Fair Value [Line Items]
Interest rate derivative assets			70,000
Level 2 | 10 year interest rate swap
Derivatives, Fair Value [Line Items]
Interest rate derivative liabilities			(492,000)
Other noncurrent assets | Level 2 | 5 year interest rate swap
Derivatives, Fair Value [Line Items]
Interest rate derivative assets		196,000	70,000
Other noncurrent assets | Level 2 | 10 year interest rate swap
Derivatives, Fair Value [Line Items]
Interest rate derivative assets		$ 561,000
Other noncurrent liabilities | Level 2 | 10 year interest rate swap
Derivatives, Fair Value [Line Items]
Interest rate derivative liabilities			$ (492,000)
London Interbank Offered Rate (LIBOR) | Minimum
Derivatives, Fair Value [Line Items]
Derivative, basis spread on variable rate		1.375%
London Interbank Offered Rate (LIBOR) | Maximum
Derivatives, Fair Value [Line Items]
Derivative, basis spread on variable rate		2.00%

Derivative Instruments and He_4

Derivative Instruments and Hedging Activities - Effect of Interest Rate Swaps on Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
5 year interest rate swap
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate swaps reclassified to earnings	$ (23)	$ 31	$ (27)	$ 136
10 year interest rate swap
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate swaps reclassified to earnings	27	81	120	283
Interest rate swap
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate swaps reclassified to earnings	$ 4	$ 112	$ 93	$ 419

FInancial Instruments (Details)

FInancial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation assets	$ 49,443	$ 46,145
Assets, fair value	50,201	46,215
Deferred compensation plan	40,452	37,280
Liabilities, fair value	40,452	37,772
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation assets	0	0
Assets, fair value	0	0
Deferred compensation plan	0	0
Liabilities, fair value	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation assets	49,443	46,145
Assets, fair value	50,201	46,215
Deferred compensation plan	40,452	37,280
Liabilities, fair value	40,452	37,772
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation assets	0	0
Assets, fair value	0	0
Deferred compensation plan	0	0
Liabilities, fair value	0	0
5 year interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate derivative assets	196	70
5 year interest rate swap | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate derivative assets		70
10 year interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate derivative assets	$ 562
Interest rate derivative liabilities		492
10 year interest rate swap | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate derivative liabilities		0
10 year interest rate swap | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate derivative liabilities		492
10 year interest rate swap | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate derivative liabilities		$ 0

Segment Reporting (Details)

Segment Reporting (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2018USD ($)segment	Sep. 30, 2017USD ($)	Dec. 31, 2017USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment			2
Revenue from unaffiliated clients	$ 182,146	$ 162,887	$ 527,639	$ 477,708
Inter-segment revenue	0	0	0	0
Segment operating income	34,879	26,669	100,644	77,563
Total assets (at end of period)	666,597	582,744	666,597	582,744	$ 584,812
Capital expenditures	4,148	4,902	16,063	14,264
Depreciation and amortization	5,680	5,993	17,366	18,486
Operating Segments | Reservoir Description
Segment Reporting Information [Line Items]
Revenue from unaffiliated clients	103,609	101,442	306,525	310,650
Inter-segment revenue	58	54	178	275
Segment operating income	14,956	14,621	44,473	49,231
Total assets (at end of period)	321,025	315,346	321,025	315,346
Capital expenditures	2,437	2,930	10,002	7,605
Depreciation and amortization	4,138	4,383	12,675	13,531
Operating Segments | Production Enhancement
Segment Reporting Information [Line Items]
Revenue from unaffiliated clients	78,537	61,445	221,114	167,058
Inter-segment revenue	141	87	293	537
Segment operating income	19,243	12,165	55,357	28,633
Total assets (at end of period)	276,345	203,413	276,345	203,413
Capital expenditures	1,680	1,605	5,465	5,394
Depreciation and amortization	1,037	1,092	3,045	3,398
Corporate & Other
Segment Reporting Information [Line Items]
Revenue from unaffiliated clients	0	0	0	0
Inter-segment revenue	(199)	(141)	(471)	(812)
Segment operating income	680	(117)	814	(301)
Total assets (at end of period)	69,227	63,985	69,227	63,985
Capital expenditures	31	367	596	1,265
Depreciation and amortization	$ 505	$ 518	$ 1,646	1,557
Discontinued Operations | General and Administrative Overhead Costs | Production Enhancement
Segment Reporting Information [Line Items]
Reclassification adjustment				682
Discontinued Operations | General and Administrative Overhead Costs | Corporate & Other
Segment Reporting Information [Line Items]
Reclassification adjustment				$ (682)