Core Laboratories (CLB) 10-Q 27 Jul 18 2018 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2018	Jul. 25, 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	Jun. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		44,212,840

Consolidated Balance Sheets Sta

Consolidated Balance Sheets Statement - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
CURRENT ASSETS:
Cash and cash equivalents	$ 13,021	$ 14,400
Accounts receivable, net of allowance for doubtful accounts of $2,474 and $2,590 at 2018 and 2017, respectively	136,148	133,097
Inventories	39,855	33,317
Prepaid expenses	13,967	12,592
Income taxes receivable	11,899	7,508
Other current assets	10,772	6,513
TOTAL CURRENT ASSETS	225,662	207,427
PROPERTY, PLANT AND EQUIPMENT, net	122,787	123,098
INTANGIBLES, net	9,786	9,396
GOODWILL	178,129	179,044
DEFERRED TAX ASSETS	11,498	10,719
OTHER ASSETS	56,882	55,128
TOTAL ASSETS	604,744	584,812
CURRENT LIABILITIES:
Accounts payable	45,278	41,697
Accrued payroll and related costs	21,427	28,887
Taxes other than payroll and income	6,986	7,313
Unearned revenue	12,608	12,627
Income taxes payable	1,167	825
Other current liabilities	13,125	9,227
TOTAL CURRENT LIABILITIES	100,591	100,576
LONG-TERM DEBT, net	241,687	226,989
CONTRACT LIABILITIES	4,664	4,442
DEFERRED COMPENSATION	54,634	52,786
DEFERRED TAX LIABILITIES	6,471	5,323
OTHER LONG-TERM LIABILITIES	38,923	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 44,203,536 outstanding at 2018 and 44,796,252 issued and 44,184,205 outstanding at 2017	1,148	1,148
Additional paid-in capital	58,927	54,463
Retained earnings	173,499	173,855
Accumulated other comprehensive income (loss)	(7,490)	(8,353)
Treasury shares (at cost), 592,716 at 2018 and 612,047 at 2017	(72,301)	(76,269)
Total Core Laboratories N.V. shareholders' equity	153,783	144,844
Non-controlling interest	3,991	3,888
TOTAL EQUITY	157,774	148,732
TOTAL LIABILITIES AND EQUITY	$ 604,744	$ 584,812

Consolidated Balance Sheets Bal

Consolidated Balance Sheets Balance Sheet Parenthetical $ in Thousands	Jun. 30, 2018€ / shares	Jun. 30, 2018USD ($)shares	Dec. 31, 2017€ / shares	Dec. 31, 2017USD ($)shares
Allowance for doubtful accounts | $		$ 2,474		$ 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)		44,203,536		44,184,205
Treasury Stock (euro per share)		592,716		612,047
Preferred stock, par value (in shares) | € / 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		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
REVENUE:
Services	$ 122,094	$ 116,940	$ 241,880	$ 237,542
Product sales	53,381	41,272	103,613	77,279
Total revenue	175,475	158,212	345,493	314,821
OPERATING EXPENSES:
Cost of services, exclusive of depreciation expense shown below	86,759	80,368	170,047	163,642
Cost of product sales, exclusive of depreciation expense shown below	37,014	33,267	73,044	63,013
General and administrative expense, exclusive of depreciation expense shown below	12,202	11,100	24,911	23,856
Depreciation	5,628	5,979	11,210	12,059
Amortization	240	209	476	434
Other (income) expense, net	183	(66)	40	923
OPERATING INCOME	33,449	27,355	65,765	50,894
Interest expense	3,296	2,692	6,416	5,310
Income from continuing operations before income tax expense	30,153	24,663	59,349	45,584
Income tax expense	5,020	3,709	10,293	6,638
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest			49,056	38,946
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent			(674)	1,445
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Noncontrolling Interest	25,133	20,954
Income (loss) from discontinued operations, net of income taxes	(328)	1,755
Net Income	24,805	22,709	48,382	40,391
Net income attributable to non-controlling interest	53	19	103	43
Net income attributable to Core Laboratories N.V.	$ 24,752	$ 22,690	$ 48,279	$ 40,348
EARNINGS PER SHARE INFORMATION:
Basic earnings per share from continuing operations (in dollar per share)	$ 0.57	$ 0.47	$ 1.11	$ 0.88
Basic loss per share from discontinued operations (in dollar per share)	(0.01)	0.04	(0.02)	0.03
Basic earnings per share attributable to Core Laboratories N.V. (in dollar per share)	0.56	0.51	1.09	0.91
Diluted earnings per share from continuing operations (in dollar per share)	0.57	0.47	1.10	0.88
Diluted loss per share from discontinued operations (in dollar per share)	(0.01)	0.04	(0.02)	0.03
Diluted earnings per share attributable to Core Laboratories N.V. (in dollar per share)	0.56	0.51	1.08	0.91
Cash dividends per share (in dollars per share)	$ 0.55	$ 0.55	$ 1.10	$ 1.10
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING:
Basic	44,203	44,164	44,191	44,162
Diluted	44,493	44,374	44,515	44,360

Consolidated Statement of Other

Consolidated Statement of Other Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net income	$ 24,805	$ 22,709	$ 48,382	$ 40,391
Gain (loss) in fair value of interest rate swaps	235	(278)	881	(197)
Interest rate swap amounts reclassified to interest expense	25	140	89	307
Income taxes on derivatives	(54)	48	(204)	(39)
Total derivatives	206	(90)	766	71
Amortization to net income of prior service cost	(18)	(19)	(39)	(38)
Amortization to net income of actuarial loss	84	110	168	220
Income taxes on pension and other postretirement benefit plans	(17)	(22)	(32)	(46)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	49	69	97	136
Total other comprehensive income (loss)	255	(21)	863	207
Comprehensive income	25,060	22,688	49,245	40,598
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	53	19	103	43
Comprehensive income attributable to Core Laboratories N.V.	$ 25,007	$ 22,669	$ 49,142	$ 40,555

Consolidated Statement of Cash

Consolidated Statement of Cash Flows Statement - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 49,056	$ 38,946
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(674)	1,445
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	48,382	40,391
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation	12,392	11,563
Depreciation and amortization	11,686	12,493
Changes to value of life insurance policies	(1,426)	(48)
Deferred income taxes	397	6,766
Other non-cash items	494	(325)
Changes in assets and liabilities:
Accounts receivable	(5,425)	(14,527)
Inventories	(7,113)	(1,926)
Prepaid expenses and other current assets	(4,067)	(3,675)
Other assets	457	(1,083)
Accounts payable	3,440	8,443
Accrued expenses	(5,830)	(12,459)
Unearned revenues	203	1,356
Other long-term liabilities	(3,507)	1,507
Net cash provided by operating activities	50,083	48,476
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(11,915)	(9,362)
Patents and other intangibles	(878)	(203)
Proceeds from sale of assets	199	511
Premiums on life insurance	(720)	(863)
Net cash used in investing activities	(13,314)	(9,917)
CASH FLOWS FROM FINANCING ACTIVITIES:
Repayment of debt borrowings	(57,000)	(67,000)
Proceeds from debt borrowings	73,000	84,000
Debt financing costs	(1,553)	0
Non-controlling interest - dividend	0	(27)
Dividends paid	(48,635)	(48,590)
Repurchase of common shares	(3,960)	(7,388)
Net cash used in financing activities	(38,148)	(39,005)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(1,379)	(446)
CASH AND CASH EQUIVALENTS, beginning of period	14,400	14,764
CASH AND CASH EQUIVALENTS, end of period	$ 13,021	$ 14,318

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 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 six months ended June 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 six months ended June 30, 2017 .

Inventories

Inventories	6 Months Ended
	Jun. 30, 2018
Inventory Disclosure [Abstract]
Inventories	INVENTORIES Inventories consisted of the following (in thousands): June 30, December 31, Finished goods $ 25,200 $ 21,668 Parts and materials 11,476 10,613 Work in progress 3,179 1,036 Total inventories $ 39,855 $ 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	6 Months Ended
	Jun. 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 June 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 June 30, 2018 and December 31, 2017 was $9.2 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 15 , Segment Reporting .

Contract Assets and Contract Li

Contract Assets and Contract Liabilities	6 Months Ended
	Jun. 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): June 30, 2018 December 31, 2017 Contract assets Current $ 673 $ 325 Contract Liabilities Current $ 4,538 $ 2,252 Non-current 4,664 4,442 $ 9,202 $ 6,694 June 30, 2018 Estimate of when contract liabilities will be recognized within 12 months $ 4,538 within 12 to 24 months 3,988 greater than 24 months 676 We did not recognize any impairment losses on our receivables and contract assets for the three and six months ended June 30, 2018 .

Discontinued Operations

Discontinued Operations	6 Months Ended
	Jun. 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 June 30, 2018 June 30, 2017 Service revenue $ 427 $ 299 Sales revenue 1,179 5,392 Total revenue 1,606 5,691 Cost of services, exclusive of depreciation expense shown below 309 63 Cost of product sales, exclusive of depreciation expense shown below 1,361 3,420 Depreciation and Amortization 44 114 Other Expense 14 42 Operating Income (Loss) (122 ) 2,052 Income tax expense (benefit) 206 297 Income (loss) from discontinued operations, net of income taxes $ (328 ) $ 1,755 Six Months Ended June 30, 2018 June 30, 2017 Service revenue $ 902 $ 633 Sales revenue 1,710 6,256 Total revenue 2,612 6,889 Cost of services, exclusive of depreciation expense shown below 874 390 Cost of product sales, exclusive of depreciation expense shown below 2,180 4,645 Depreciation and Amortization 102 236 Other Expense (income) 22 (74 ) Operating Income (loss) (566 ) 1,692 Income tax expense (benefit) 108 247 Income (loss) from discontinued operations, net of income taxes $ (674 ) $ 1,445 June 30, 2018 December 31, 2017 Current assets $ 2,529 $ 2,549 Non-current assets 1,861 1,048 Total assets $ 4,390 $ 3,597 Current liabilities $ 840 $ 221 Non-current liabilities 75 75 Total liabilities $ 915 $ 296 Net cash provided by (used in) operating activities of discontinued operations for the three and six months ended June 30, 2018 was $(0.4) million and $0.1 million , respectively.

Long-Term Debt

Long-Term Debt	6 Months Ended
	Jun. 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): June 30, December 31, Senior notes $ 150,000 $ 150,000 Credit facility 94,000 78,000 Total long-term debt 244,000 228,000 Less: Debt issuance costs (2,313 ) (1,011 ) Long-term debt, net $ 241,687 $ 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 $12.8 million at June 30, 2018 , resulting in an available borrowing capacity under the Credit Facility of $193.2 million . In addition to those items under the Credit Facility, we had $13.4 million of outstanding letters of credit and performance guarantees and bonds from other sources as of June 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 13 - Derivative Instruments and Hedging Activities . The estimated fair value of total debt at June 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	6 Months Ended
	Jun. 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 Six Months Ended June 30, June 30, 2018 2017 2018 2017 Service cost $ 392 $ 366 $ 741 $ 741 Interest cost 336 268 636 543 Expected return on plan assets (290 ) (228 ) (549 ) (460 ) Amortization of prior service cost (18 ) (19 ) (39 ) (38 ) Amortization of actuarial loss 84 110 168 220 Net periodic pension cost $ 504 $ 497 $ 957 $ 1,006 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 six months ended June 30, 2018 , we contributed $1.4 million to fund the estimated 2018 premiums on investment contracts held by the Dutch Plan.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 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	6 Months Ended
	Jun. 30, 2018
Equity [Abstract]
Equity	EQUITY During the three and six months ended June 30, 2018 , we repurchased 5,960 and 36,258 of our common shares for $0.6 million and $4.0 million , respectively. These included rights to 5,960 and 16,258 shares valued at $0.6 million and $1.7 million , respectively, that 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 19,903 and 55,589 treasury shares upon vesting of stock-based awards during the three and six months ended June 30, 2018 , respectively. In February and May 2018 , we paid a quarterly dividend of $0.55 per share of common stock. In addition, on July 13, 2018 , we declared a quarterly dividend of $0.55 per share of common stock for shareholders of record on July 23, 2018 and payable on August 13, 2018 . The following table summarizes our changes in equity for the six months ended June 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 — 4,464 — — 7,928 — 12,392 Repurchase of common shares — — — — (3,960 ) — (3,960 ) Dividends paid — — (48,635 ) — — — (48,635 ) Amortization of deferred pension costs, net of tax — — — 97 — — 97 Interest rate swaps, net of tax — — — 766 — — 766 Net income — — 48,279 — — 103 48,382 June 30, 2018 $ 1,148 $ 58,927 $ 173,499 $ (7,490 ) $ (72,301 ) $ 3,991 $ 157,774 Accumulated other comprehensive income (loss) consisted of the following (in thousands): June 30, December 31, Prior service cost $ 512 $ 541 Unrecognized net actuarial loss (8,577 ) (8,703 ) Fair value of derivatives, net of tax 575 (191 ) Total accumulated other comprehensive income (loss) $ (7,490 ) $ (8,353 )

Earnings per Share

Earnings per Share	6 Months Ended
	Jun. 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 Six Months Ended June 30, June 30, 2018 2017 2018 2017 Weighted average basic common shares outstanding 44,203 44,164 44,191 44,162 Effect of dilutive securities: Performance shares 205 148 255 143 Restricted stock 85 62 69 55 Weighted average diluted common and potential common shares outstanding 44,493 44,374 44,515 44,360

Other (Income) Expense, Net

Other (Income) Expense, Net	6 Months Ended
	Jun. 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 Six Months Ended June 30, June 30, 2018 2017 2018 2017 Sale of assets $ 81 $ (123 ) $ (508 ) $ (302 ) Results of non-consolidated subsidiaries (11 ) (96 ) (69 ) (175 ) Foreign exchange 654 358 1,086 455 Rents and royalties (141 ) (109 ) (236 ) (231 ) Return on pension assets and other pension costs (224 ) (137 ) (420 ) (278 ) Severance, compensation and other charges — — — 1,145 Other, net (176 ) 41 187 309 Total other (income) expense, net $ 183 $ (66 ) $ 40 $ 923 Foreign exchange gains and losses are summarized in the following table (in thousands): Three Months Ended Six Months Ended June 30, June 30, (Gains) losses by currency 2018 2017 2018 2017 Angolan Kwanza $ 57 $ (4 ) $ 161 $ (3 ) Australian Dollar 32 18 110 13 British Pound 104 (74 ) (23 ) (55 ) Canadian Dollar 243 (58 ) 357 (77 ) Euro (259 ) 732 (16 ) 835 Indonesian Rupiah 142 5 178 (25 ) Other currencies, net 335 (261 ) 319 (233 ) Total loss, net $ 654 $ 358 $ 1,086 $ 455

Income Tax Expense

Income Tax Expense	6 Months Ended
	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Income Tax Expense	INCOME TAX EXPENSE The effective tax rates for the three months ended June 30, 2018 and 2017 were 16.6% and 15.0% , respectively, and for the six months ended June 30, 2018 and 2017 were 17.3% and 14.6% , respectively. Income tax expense of $5.0 million in the second quarter of 2018 increased by $1.3 million compared to $3.7 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.

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	6 Months Ended
	Jun. 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 June 30, 2018 , we had fixed rate long-term debt aggregating $200 million and variable rate long-term debt aggregating $44 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 June 30, 2018 December 31, 2017 Balance Sheet Classification Derivatives designated as hedges: 5 year interest rate swap $ 205 $ 70 Other long-term assets 10 year interest rate swap 344 (492 ) Other long-term assets (liabilities) $ 549 $ (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 Six Months Ended June 30, June 30, 2018 2017 2018 2017 Income Statement Classification Derivatives designated as hedges: 5 year interest rate swap $ (12 ) $ 46 $ (4 ) $ 105 Increase (decrease) to interest expense 10 year interest rate swap 37 94 93 202 Increase to interest expense $ 25 $ 140 $ 89 $ 307

Financial Instruments

Financial Instruments	6 Months Ended
	Jun. 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 June 30, 2018 Total Level 1 Level 2 Level 3 Assets: Deferred compensation assets (1) $ 47,327 $ — $ 47,327 $ — 5 year interest rate swap 205 — 205 — 10 year interest rate swap 344 — 344 — 47,876 — 47,876 — Liabilities: Deferred compensation plan $ 38,583 $ — $ 38,583 $ — $ 38,583 $ — $ 38,583 $ — 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	6 Months Ended
	Jun. 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 June 30, 2018 Revenue from unaffiliated clients $ 102,107 $ 73,368 $ — $ 175,475 Inter-segment revenue 73 101 (174 ) — Segment operating income 14,760 18,427 262 33,449 Total assets (at end of period) 319,122 218,011 67,611 604,744 Capital expenditures 5,384 1,938 150 7,472 Depreciation and amortization 4,290 1,006 572 5,868 Three Months Ended June 30, 2017 Revenue from unaffiliated clients $ 104,313 $ 53,899 $ — $ 158,212 Inter-segment revenue 47 249 (296 ) — Segment operating income (loss) 18,670 8,713 (28 ) 27,355 Total assets (at end of period) 319,433 200,583 63,742 583,758 Capital expenditures 2,098 769 46 2,913 Depreciation and amortization 4,528 1,142 518 6,188 Six Months Ended June 30, 2018 Revenue from unaffiliated clients $ 202,916 $ 142,577 $ — $ 345,493 Inter-segment revenue 120 152 (272 ) — Segment operating income 29,517 36,114 134 65,765 Total assets 319,122 218,011 67,611 604,744 Capital expenditures 7,565 3,785 565 11,915 Depreciation and amortization 8,537 2,008 1,141 11,686 Six Months Ended June 30, 2017 Revenue from unaffiliated clients $ 209,208 $ 105,613 $ — $ 314,821 Inter-segment revenue 221 450 (671 ) — Segment operating income (loss) 34,610 17,150 (866 ) 50,894 Total assets 319,433 200,583 63,742 583,758 Capital expenditures 4,675 3,789 898 9,362 Depreciation and amortization 9,148 2,306 1,039 12,493 (1) "Corporate & Other" represents those items that are not directly related to a particular segment, eliminations and the assets and liabilities of discontinued operations.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	6 Months Ended
	Jun. 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 six months ended June 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. We 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 Polici23

Significant Accounting Policies Update (Policies)	6 Months Ended
	Jun. 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 June 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 June 30, 2018 and December 31, 2017 was $9.2 million and $6.7 million , respectively.

Inventories (Tables)

Inventories (Tables)	6 Months Ended
	Jun. 30, 2018
Inventory Disclosure [Abstract]
Schedule of Inventory, Current	Inventories consisted of the following (in thousands): June 30, December 31, Finished goods $ 25,200 $ 21,668 Parts and materials 11,476 10,613 Work in progress 3,179 1,036 Total inventories $ 39,855 $ 33,317

Contract Assets and Contract 25

Contract Assets and Contract Liabilities (Tables)	6 Months Ended
	Jun. 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): June 30, 2018 December 31, 2017 Contract assets Current $ 673 $ 325 Contract Liabilities Current $ 4,538 $ 2,252 Non-current 4,664 4,442 $ 9,202 $ 6,694 June 30, 2018 Estimate of when contract liabilities will be recognized within 12 months $ 4,538 within 12 to 24 months 3,988 greater than 24 months 676

Discontinued Operations (Tables

Discontinued Operations (Tables)	6 Months Ended
	Jun. 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 June 30, 2018 June 30, 2017 Service revenue $ 427 $ 299 Sales revenue 1,179 5,392 Total revenue 1,606 5,691 Cost of services, exclusive of depreciation expense shown below 309 63 Cost of product sales, exclusive of depreciation expense shown below 1,361 3,420 Depreciation and Amortization 44 114 Other Expense 14 42 Operating Income (Loss) (122 ) 2,052 Income tax expense (benefit) 206 297 Income (loss) from discontinued operations, net of income taxes $ (328 ) $ 1,755 Six Months Ended June 30, 2018 June 30, 2017 Service revenue $ 902 $ 633 Sales revenue 1,710 6,256 Total revenue 2,612 6,889 Cost of services, exclusive of depreciation expense shown below 874 390 Cost of product sales, exclusive of depreciation expense shown below 2,180 4,645 Depreciation and Amortization 102 236 Other Expense (income) 22 (74 ) Operating Income (loss) (566 ) 1,692 Income tax expense (benefit) 108 247 Income (loss) from discontinued operations, net of income taxes $ (674 ) $ 1,445 June 30, 2018 December 31, 2017 Current assets $ 2,529 $ 2,549 Non-current assets 1,861 1,048 Total assets $ 4,390 $ 3,597 Current liabilities $ 840 $ 221 Non-current liabilities 75 75 Total liabilities $ 915 $ 296

Long-Term Debt (Tables)

Long-Term Debt (Tables)	6 Months Ended
	Jun. 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): June 30, December 31, Senior notes $ 150,000 $ 150,000 Credit facility 94,000 78,000 Total long-term debt 244,000 228,000 Less: Debt issuance costs (2,313 ) (1,011 ) Long-term debt, net $ 241,687 $ 226,989

Pensions (Tables)

Pensions (Tables)	6 Months Ended
	Jun. 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 Six Months Ended June 30, June 30, 2018 2017 2018 2017 Service cost $ 392 $ 366 $ 741 $ 741 Interest cost 336 268 636 543 Expected return on plan assets (290 ) (228 ) (549 ) (460 ) Amortization of prior service cost (18 ) (19 ) (39 ) (38 ) Amortization of actuarial loss 84 110 168 220 Net periodic pension cost $ 504 $ 497 $ 957 $ 1,006

Equity (Tables)

Equity (Tables)	6 Months Ended
	Jun. 30, 2018
Equity [Abstract]
Schedule of Stockholders Equity	The following table summarizes our changes in equity for the six months ended June 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 — 4,464 — — 7,928 — 12,392 Repurchase of common shares — — — — (3,960 ) — (3,960 ) Dividends paid — — (48,635 ) — — — (48,635 ) Amortization of deferred pension costs, net of tax — — — 97 — — 97 Interest rate swaps, net of tax — — — 766 — — 766 Net income — — 48,279 — — 103 48,382 June 30, 2018 $ 1,148 $ 58,927 $ 173,499 $ (7,490 ) $ (72,301 ) $ 3,991 $ 157,774
Schedule of Accumulated Other Comprehensive Income (Loss)	Accumulated other comprehensive income (loss) consisted of the following (in thousands): June 30, December 31, Prior service cost $ 512 $ 541 Unrecognized net actuarial loss (8,577 ) (8,703 ) Fair value of derivatives, net of tax 575 (191 ) Total accumulated other comprehensive income (loss) $ (7,490 ) $ (8,353 )

Earnings per Share (Tables)

Earnings per Share (Tables)	6 Months Ended
	Jun. 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 Six Months Ended June 30, June 30, 2018 2017 2018 2017 Weighted average basic common shares outstanding 44,203 44,164 44,191 44,162 Effect of dilutive securities: Performance shares 205 148 255 143 Restricted stock 85 62 69 55 Weighted average diluted common and potential common shares outstanding 44,493 44,374 44,515 44,360

Other (Income) Expense, Net (Ta

Other (Income) Expense, Net (Tables)	6 Months Ended
	Jun. 30, 2018
Other Income and Expenses [Abstract]
Foreign Currency Gains Losses By Currency	Foreign exchange gains and losses are summarized in the following table (in thousands): Three Months Ended Six Months Ended June 30, June 30, (Gains) losses by currency 2018 2017 2018 2017 Angolan Kwanza $ 57 $ (4 ) $ 161 $ (3 ) Australian Dollar 32 18 110 13 British Pound 104 (74 ) (23 ) (55 ) Canadian Dollar 243 (58 ) 357 (77 ) Euro (259 ) 732 (16 ) 835 Indonesian Rupiah 142 5 178 (25 ) Other currencies, net 335 (261 ) 319 (233 ) Total loss, net $ 654 $ 358 $ 1,086 $ 455
Schedule of Other Operating Cost and Expense, by Component	The components of Other (income) expense, net, were as follows (in thousands): Three Months Ended Six Months Ended June 30, June 30, 2018 2017 2018 2017 Sale of assets $ 81 $ (123 ) $ (508 ) $ (302 ) Results of non-consolidated subsidiaries (11 ) (96 ) (69 ) (175 ) Foreign exchange 654 358 1,086 455 Rents and royalties (141 ) (109 ) (236 ) (231 ) Return on pension assets and other pension costs (224 ) (137 ) (420 ) (278 ) Severance, compensation and other charges — — — 1,145 Other, net (176 ) 41 187 309 Total other (income) expense, net $ 183 $ (66 ) $ 40 $ 923

Derivative Instruments and He32

Derivative Instruments and Hedging Activities (Tables)	6 Months Ended
	Jun. 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 June 30, 2018 December 31, 2017 Balance Sheet Classification Derivatives designated as hedges: 5 year interest rate swap $ 205 $ 70 Other long-term assets 10 year interest rate swap 344 (492 ) Other long-term assets (liabilities) $ 549 $ (422 )
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 Six Months Ended June 30, June 30, 2018 2017 2018 2017 Income Statement Classification Derivatives designated as hedges: 5 year interest rate swap $ (12 ) $ 46 $ (4 ) $ 105 Increase (decrease) to interest expense 10 year interest rate swap 37 94 93 202 Increase to interest expense $ 25 $ 140 $ 89 $ 307

Financial Instruments (Tables)

Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	The following table summarizes the fair value balances (in thousands): Fair Value Measurement at June 30, 2018 Total Level 1 Level 2 Level 3 Assets: Deferred compensation assets (1) $ 47,327 $ — $ 47,327 $ — 5 year interest rate swap 205 — 205 — 10 year interest rate swap 344 — 344 — 47,876 — 47,876 — Liabilities: Deferred compensation plan $ 38,583 $ — $ 38,583 $ — $ 38,583 $ — $ 38,583 $ — 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)	6 Months Ended
	Jun. 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 June 30, 2018 Revenue from unaffiliated clients $ 102,107 $ 73,368 $ — $ 175,475 Inter-segment revenue 73 101 (174 ) — Segment operating income 14,760 18,427 262 33,449 Total assets (at end of period) 319,122 218,011 67,611 604,744 Capital expenditures 5,384 1,938 150 7,472 Depreciation and amortization 4,290 1,006 572 5,868 Three Months Ended June 30, 2017 Revenue from unaffiliated clients $ 104,313 $ 53,899 $ — $ 158,212 Inter-segment revenue 47 249 (296 ) — Segment operating income (loss) 18,670 8,713 (28 ) 27,355 Total assets (at end of period) 319,433 200,583 63,742 583,758 Capital expenditures 2,098 769 46 2,913 Depreciation and amortization 4,528 1,142 518 6,188 Six Months Ended June 30, 2018 Revenue from unaffiliated clients $ 202,916 $ 142,577 $ — $ 345,493 Inter-segment revenue 120 152 (272 ) — Segment operating income 29,517 36,114 134 65,765 Total assets 319,122 218,011 67,611 604,744 Capital expenditures 7,565 3,785 565 11,915 Depreciation and amortization 8,537 2,008 1,141 11,686 Six Months Ended June 30, 2017 Revenue from unaffiliated clients $ 209,208 $ 105,613 $ — $ 314,821 Inter-segment revenue 221 450 (671 ) — Segment operating income (loss) 34,610 17,150 (866 ) 50,894 Total assets 319,433 200,583 63,742 583,758 Capital expenditures 4,675 3,789 898 9,362 Depreciation and amortization 9,148 2,306 1,039 12,493 (1) "Corporate & Other" represents those items that are not directly related to a particular segment, eliminations and the assets and liabilities of discontinued operations.

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Finished goods	$ 25,200	$ 21,668
Parts and materials	11,476	10,613
Work in progress	3,179	1,036
Total inventories	$ 39,855	$ 33,317

Significant Accounting Polici36

Significant Accounting Policies Update (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Accounting Changes and Error Corrections [Abstract]
Contract with Customer, Asset, Net, Current	$ 673	$ 325
Contract with Customer, Liability, Current	4,538	2,252
CONTRACT LIABILITIES	9,202	6,694
CONTRACT LIABILITIES	$ 4,664	$ 4,442

Contract Assets and Contract 37

Contract Assets and Contract Liabilities - Changes in Net Contract Assets (Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
CONTRACT LIABILITIES	$ 4,664	$ 4,442

Contract Assets and Contract 38

Contract Assets and Contract Liabilities - Current and Long-term Contract Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
CONTRACT LIABILITIES	$ 9,202	$ 6,694
Contract with Customer, Liability, Current	(4,538)	$ (2,252)
within 12 to 24 months
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
CONTRACT LIABILITIES	3,988
greater than 24 months
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
CONTRACT LIABILITIES	$ 676

Discontinued Operations (Detail

Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Discontinued Operations and Disposal Groups [Abstract]
Service revenue	$ 427	$ 299	$ 902	$ 633
Sales revenue	1,179	5,392	1,710	6,256
Total revenue	1,606	5,691	2,612	6,889
Cost of services, exclusive of depreciation expense shown below	309	63	874	390
Cost of product sales, exclusive of depreciation expense shown below	1,361	3,420	2,180	4,645
Depreciation and Amortization	44	114	102	236
Other Expense	14	42	22	(74)
Operating Income (Loss)	(122)	2,052	(566)	1,692
Income tax expense (benefit)	206	297	108	247
Income (loss) from discontinued operations, net of income taxes	(328)	1,755	(674)	1,445
Current assets	2,529	2,549	2,529	2,549
Non-current assets	1,861	1,048	1,861	1,048
Total assets	4,390	3,597	4,390	3,597
Current liabilities	840	221	840	221
Non-current liabilities	75	75	75	75
Total liabilities	$ 915	$ 296	915	296
Cash provided by (used in) operating activities, discontinued operations			$ (400)	$ 100

Long-Term Debt (Details)

Long-Term Debt (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)interest_rate_swap
Debt Instrument [Line Items]
Long-term Debt	$ 244,000	$ 228,000
Less: Debt issuance costs	(2,313)	(1,011)
Long-term debt, net	241,687	226,989
Line of Credit Facility, Prior Borrowing Capacity	400,000
Line of credit facility, current borrowing capacity	300,000
Line of Credit Facility, Extension Capacity	100,000
Line of credit facility, maximum borrowing capacity	400,000
Performance bonds under credit facility	12,800
Line of credit facility, remaining borrowing capacity	193,200
Performance bonds	$ 13,400
Number of interest rate swaps | interest_rate_swap			2
Minimum Interest Coverage Ratio	300.00%
Maximum Leverage Ratio	250.00%
Senior Notes
Debt Instrument [Line Items]
Long-term Debt	$ 150,000	150,000
Face amount	150,000
Line of Credit
Debt Instrument [Line Items]
Long-term Debt	$ 94,000	$ 78,000
Maturity date	Jun. 19, 2023
Senior Notes Series A
Debt Instrument [Line Items]
Face amount	$ 75,000
Interest rate, effective percentage	4.01%
Maturity date	Sep. 30, 2021
Senior Notes Series B
Debt Instrument [Line Items]
Face amount	$ 75,000
Interest rate, effective percentage	4.11%
Maturity date	Sep. 30, 2023
Interest Rate Swap
Debt Instrument [Line Items]
Notional amount			$ 50,000
London Interbank Offered Rate (LIBOR) [Member] | Minimum
Debt Instrument [Line Items]
Derivative, basis spread on variable rate	1.38%
London Interbank Offered Rate (LIBOR) [Member] | Maximum
Debt Instrument [Line Items]
Derivative, basis spread on variable rate	2.00%

Pensions (Details)

Pensions (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Retirement Benefits [Abstract]
Service cost	$ 392	$ 366	$ 741	$ 741
Interest cost	336	268	636	543
Expected return on plan assets	(290)	(228)	(549)	(460)
Amortization of prior service cost	18	19	39	38
Amortization of actuarial loss	84	110	168	220
Net periodic pension cost	$ 504	$ 497	957	$ 1,006
Contributions by employer			$ 1,400

Equity (Narrative) (Details)

Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Equity [Abstract]
Treasury stock, shares, acquired	5,960		36,258
Treasury stock, value	$ 0.6		$ 4
Treasury shares, acquired, tax burden	5,960		16,258
Treasury shares, acquired, value, tax burden	$ 0.6		$ 1.7
Treasury stock reissued	19,903		55,589
Cash dividends per share (in dollars per share)	$ 0.55	$ 0.55	$ 1.10	$ 1.10
Dividends declared (in dollars per share)	$ 0.55

Equity (Details)

Equity (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			$ 148,732
Stock based-awards			12,392
Repurchase of common shares			(3,960)
Dividends paid			(48,635)
Amortization of deferred pension costs, net of tax			97
Interest rate swaps, net of tax			766
Net income	$ 24,805	$ 22,709	48,382	$ 40,391
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	53	$ 19	103	$ 43
Ending balance	157,774		157,774
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
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			4,464
Repurchase of common shares			0
Dividends paid			0
Amortization of deferred pension costs, net of tax			0
Interest rate swaps, net of tax			0
Net income			0
Ending balance	58,927		58,927
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			173,855
Stock based-awards			0
Repurchase of common shares			0
Dividends paid			(48,635)
Amortization of deferred pension costs, net of tax			0
Interest rate swaps, net of tax			0
Net income			48,279
Ending balance	173,499		173,499
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
Amortization of deferred pension costs, net of tax			97
Interest rate swaps, net of tax			766
Net income			0
Ending balance	(7,490)		(7,490)
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			(76,269)
Stock based-awards			7,928
Repurchase of common shares			(3,960)
Dividends paid			0
Amortization of deferred pension costs, net of tax			0
Interest rate swaps, net of tax			0
Net income			0
Ending balance	(72,301)		(72,301)
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
Amortization of deferred pension costs, net of tax			0
Interest rate swaps, net of tax			0
Ending balance	$ 3,991		$ 3,991

Equity (Comprehensive Income) (

Equity (Comprehensive Income) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Equity [Abstract]
Prior service cost	$ 512	$ 541
Unrecognized net actuarial loss	(8,577)	(8,703)
Fair value of derivatives, net of tax	575	(191)
Total accumulated other comprehensive income (loss)	$ (7,490)	$ (8,353)

Earnings per Share (Details)

Earnings per Share (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Weighted average basic common shares outstanding	44,203	44,164	44,191	44,162
Performance shares (in shares)	205	148	255	143
Restricted stock (in shares)	85	62	69	55
Weighted average diluted common and potential common shares outstanding	44,493	44,374	44,515	44,360

Other (Income) Expense, Net (De

Other (Income) Expense, Net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement Location [Line Items]
Total other (income) expense, net	$ 183	$ (66)	$ 40	$ 923
Sale of assets
Income Statement Location [Line Items]
Total other (income) expense, net	81	(123)	(508)	(302)
Other, net
Income Statement Location [Line Items]
Total other (income) expense, net	(176)	41	187	309
Foreign exchange
Income Statement Location [Line Items]
Total other (income) expense, net	654	358	1,086	455
Rents and royalties
Income Statement Location [Line Items]
Total other (income) expense, net	(141)	(109)	(236)	(231)
Severance, compensation and other charges
Income Statement Location [Line Items]
Total other (income) expense, net	0	0	0	1,145
Investment Income [Member]
Income Statement Location [Line Items]
Total other (income) expense, net	$ (11)	$ (96)	$ (69)	$ (175)

Other (Income) Expense, Net (Fo

Other (Income) Expense, Net (Foreign Currency (Gain) Loss by Currency) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Foreign exchange	$ 654,000	$ 358,000	$ 1,086,000	$ 455,000
Angola, Kwanza
Foreign exchange	57,000	(4,000)	161,000	(3,000)
AustralianDollar [Member]
Foreign exchange	32,000	18,000	110,000	13,000
British Pound
Foreign exchange	104,000	(74,000)	(23,000)	(55,000)
Canadian Dollar
Foreign exchange	243,000	(58,000)	357,000	(77,000)
Euro
Foreign exchange	(259,000)	732,000	(16,000)	835,000
Other Currencies Net [Member]
Foreign exchange	335,000	(261,000)	319,000	(233,000)
Indonesian Rupiah [Member]
Foreign exchange	$ 142,000	$ 5,000	$ 178,000	$ (25,000)

Income Tax Expense (Details)

Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Effective income tax rate	17.00%	15.00%	17.00%	15.00%
Change in income tax expense	$ 1,300
Income tax expense	$ 5,020	$ 3,709	$ 10,293	$ 6,638

Derivative Instruments and He49

Derivative Instruments and Hedging Activities (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)interest_rate_swap
Derivatives, Fair Value [Line Items]
Number of interest rate swaps | interest_rate_swap			2
Long-term debt, percentage bearing fixed interest, amount	$ 200,000
Long-term debt, percentage bearing variable interest, amount	44,000
5 year interest rate swap
Derivatives, Fair Value [Line Items]
Notional amount	$ 25,000
Fixed interest rate	2.50%
Maturity date	Aug. 29, 2024
Interest rate derivative assets	$ 205
Interest rate derivative liabilities		$ (492)
10 year interest rate swap
Derivatives, Fair Value [Line Items]
Notional amount	$ 25,000
Fixed interest rate	1.73%
Maturity date	Aug. 29, 2019
Interest rate derivative assets	$ 344
Interest Rate Swap
Derivatives, Fair Value [Line Items]
Notional amount			$ 50,000
Interest rate derivative assets	549
Interest rate derivative liabilities		(422)
Other Noncurrent Liabilities [Member] | Level 2 | 10 year interest rate swap
Derivatives, Fair Value [Line Items]
Interest rate derivative liabilities		(492)
Other Assets [Member] | Level 2 | 5 year interest rate swap
Derivatives, Fair Value [Line Items]
Interest rate derivative assets	205	$ 70
Other Assets [Member] | Level 2 | 10 year interest rate swap
Derivatives, Fair Value [Line Items]
Interest rate derivative assets	$ 344
London Interbank Offered Rate (LIBOR) [Member] | Minimum
Derivatives, Fair Value [Line Items]
Derivative, basis spread on variable rate	1.38%
London Interbank Offered Rate (LIBOR) [Member] | Maximum
Derivatives, Fair Value [Line Items]
Derivative, basis spread on variable rate	2.00%

Derivative Instruments and He50

Derivative Instruments and Hedging Activities - Effect of Interest Rate Swaps on Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
5 year interest rate swap
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate swaps reclassified to earnings	$ 37	$ 94	$ 93	$ 202
10 year interest rate swap
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate swaps reclassified to earnings	(12)	46	(4)	105
Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate swaps reclassified to earnings	$ 25	$ 140	$ 89	$ 307

Financial Instruments FInancial

Financial Instruments FInancial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation assets	$ 47,327	$ 46,145
Assets, fair value	47,876	46,215
Deferred compensation plan	38,583	37,280
Liabilities, fair value	38,583	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	47,327	46,145
Assets, fair value	47,876	46,215
Deferred compensation plan	38,583	37,280
Liabilities, fair value	38,583	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	205
Interest rate derivative liabilities		$ 492
10 year interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate derivative assets	$ 344

Segment Reporting (Details)

Segment Reporting (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Segment Reporting Information [Line Items]
Revenue from unaffiliated clients	$ 175,475	$ 158,212	$ 345,493	$ 314,821
Inter-segment revenue	0	0	0	0
Segment operating income	33,449	27,355	65,765	50,894
Total assets (at end of period)	604,744	583,758	604,744	583,758	$ 584,812
Capital expenditures	7,472	2,913	11,915	9,362
Depreciation and amortization	5,868	6,188	11,686	12,493
Services	122,094	116,940	241,880	237,542
Product sales	53,381	41,272	103,613	77,279
Operating Segments | Reservoir Description
Segment Reporting Information [Line Items]
Revenue from unaffiliated clients	102,107	104,313	202,916	209,208
Inter-segment revenue	73	47	120	221
Segment operating income	14,760	18,670	29,517	34,610
Total assets (at end of period)	319,122	319,433	319,122	319,433	319,433
Capital expenditures	5,384	2,098	7,565	4,675
Depreciation and amortization	4,290	4,528	8,537	9,148
Operating Segments | Production Enhancement
Segment Reporting Information [Line Items]
Revenue from unaffiliated clients	73,368	53,899	142,577	105,613
Inter-segment revenue	101	249	152	450
Segment operating income	18,427	8,713	36,114	17,150
Total assets (at end of period)	218,011	200,583	218,011	200,583	200,583
Capital expenditures	1,938	769	3,785	3,789
Depreciation and amortization	1,006	1,142	2,008	2,306
Corporate & Other
Segment Reporting Information [Line Items]
Revenue from unaffiliated clients	0	0	0	0
Inter-segment revenue	(174)	(296)	(272)	(671)
Segment operating income	262	(28)	134	(866)
Total assets (at end of period)	67,611	63,742	67,611	63,742	$ 63,742
Capital expenditures	150	46	565	898
Depreciation and amortization	$ 572	$ 518	$ 1,141	$ 1,039