Ion Geophysical (IOGPQ) 8-K 8 Nov 19 Other Events Financial data

Document and Entity Information

Document and Entity Information	Nov. 08, 2019
Document and Entity Information [Abstract]
Entity Registrant Name	ION GEOPHYSICAL CORP
Entity Central Index Key	0000866609
Document Type	8-K
Document Period End Date	Nov. 8, 2019
Amendment Flag	false
Entity Emerging Growth Company	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	[1]
Current assets:
Cash and cash equivalents	$ 33,551	$ 52,056	$ 52,652
Accounts receivable, net	26,128	19,478
Unbilled receivables	44,032	37,304
Inventories, net	14,130	14,508
Prepaid expenses and other current assets	7,782	7,643
Total current assets	125,623	130,989
Deferred income tax asset	7,191	1,753
Property, plant, equipment and seismic rental equipment, net	13,041	52,153
Multi-client data library, net	73,544	89,300
Goodwill	22,915	24,089	22,208
Other assets	2,435	2,785
Total assets	244,749	301,069
Current liabilities:
Current maturities of long-term debt	2,228	40,024
Accounts payable	34,913	24,951
Accrued expenses	31,411	38,697
Accrued multi-client data library royalties	29,256	27,035
Deferred revenue	7,710	8,910
Total current liabilities	105,518	139,617
Long-term debt, net of current maturities	119,513	116,720
Other long-term liabilities	11,894	13,926
Total liabilities	236,925	270,263
Equity:
Common stock, $0.01 par value; authorized 26,666,667 shares; outstanding 14,015,615 and 12,019,701 shares at December 31, 2018 and 2017, respectively.	140	120
Additional paid-in capital	952,626	903,247
Accumulated deficit	(926,092)	(854,921)
Accumulated other comprehensive loss	(20,442)	(18,879)
Total stockholders’ equity	6,232	29,567
Noncontrolling interests	1,592	1,239
Total equity	7,824	30,806	$ 53,398	$ 112,040
Total liabilities and equity	$ 244,749	$ 301,069
[1]	The figures for January 1, 2016, set forth in the tables above have been retroactively adjusted to reflect the one-for-fifteen reverse stock split completed on February 4, 2016.

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Common stock, par value (usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	26,666,667	26,666,667
Common stock, shares outstanding (in shares)	14,015,615	12,019,701

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net revenues	$ 180,045	$ 197,554	$ 172,808
Cost of services and products	120,425	121,915	136,776
Gross profit	59,620	75,639	36,032
Operating expenses:
Research, development and engineering	18,182	16,431	17,833
Marketing and sales	21,793	20,778	17,371
General, administrative and other operating expenses	37,364	47,129	43,999
Impairment of long-lived assets	36,553	0	0
Total operating expenses	113,892	84,338	79,203
Loss from operations	(54,272)	(8,699)	(43,171)
Interest expense, net	(12,972)	(16,709)	(18,485)
Other income (expense), net	(436)	(3,945)	1,350
Loss before income taxes	(67,680)	(29,353)	(60,306)
Income tax expense	2,718	24	4,421
Net income (loss)	(70,398)	(29,377)	(64,727)
Net income attributable to noncontrolling interests	(773)	(865)	(421)
Net loss attributable to ION	$ (71,171)	$ (30,242)	$ (65,148)
Net loss per share:
Basic (usd per share)	$ (5.20)	$ (2.55)	$ (5.71)
Diluted (usd per share)	$ (5.20)	$ (2.55)	$ (5.71)
Weighted average number of common shares outstanding:
Basic (in shares)	13,692	11,876	11,400
Diluted (in shares)	13,692	11,876	11,400
Service
Net revenues	$ 139,038	$ 159,410	$ 130,640
Cost of services and products	100,557	103,124	115,763
Product
Net revenues	41,007	38,144	42,168
Cost of services and products	$ 19,868	$ 18,791	$ 21,013

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (70,398)	$ (29,377)	$ (64,727)
Other comprehensive income (loss), net of taxes, as appropriate:
Foreign currency translation adjustments	(1,563)	2,869	(6,967)
Comprehensive net loss	(71,961)	(26,508)	(71,694)
Comprehensive income attributable to noncontrolling interests	(773)	(865)	(421)
Comprehensive net loss attributable to ION	$ (72,734)	$ (27,373)	$ (72,115)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net loss	$ (70,398)	$ (29,377)	$ (64,727)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization (other than multi-client library)	8,763	16,592	21,975
Amortization of multi-client data library	48,988	47,102	33,335
Impairment of long-lived assets	36,553	0	0
Impairment of multi-client data library	0	2,304	0
Stock-based compensation expense	3,337	2,552	3,267
Accrual (reduction) of loss contingency related to legal proceedings	0	5,000	(1,168)
Loss on bond exchange	0	0	2,182
Write-down of excess and obsolete inventory	665	398	429
Deferred income taxes	(6,252)	(5,420)	(1,181)
Change in operating assets and liabilities:
Accounts receivable	(7,024)	1,692	20,426
Unbilled receivables	(5,245)	(23,947)	6,543
Inventories	(353)	190	2,312
Accounts payable, accrued expenses and accrued royalties	(7,600)	1,443	(5,085)
Deferred revenue	(1,112)	5,131	(2,759)
Other assets and liabilities	6,776	3,952	(14,556)
Net cash provided by operating activities	7,098	27,612	993
Cash flows from investing activities:
Investment in multi-client data library	(28,276)	(23,710)	(14,884)
Purchase of property, plant, equipment and seismic rental equipment	(1,514)	(1,063)	(1,458)
Proceeds from sale of cost method investments	0	0	2,698
Net cash used in investing activities	(29,790)	(24,773)	(13,644)
Cash flows from financing activities:
Borrowings under revolving line of credit	0	0	15,000
Repayments under revolving line of credit	(10,000)	0	(5,000)
Payments on notes payable and long-term debt	(30,807)	(4,816)	(23,634)
Cost associated with issuance of debt	(1,247)	(53)	(6,744)
Net proceeds from issuance of stocks	46,999	0	0
Repurchase of common stock	0	0	(964)
Proceeds from employee stock purchases and exercise of stock options	214	1,619	0
Dividend payment to noncontrolling interest	(200)	(100)	0
Other financing activities	(1,151)	(243)	(252)
Net cash provided by (used in) financing activities	3,808	(3,593)	(21,594)
Effect of change in foreign currency exchange rates on cash, cash equivalents and restricted cash	319	(260)	1,386
Net decrease in cash, cash equivalents and restricted cash	(18,565)	(1,014)	(32,859)
Cash, cash equivalents and restricted cash at beginning of period	52,419	53,433	86,292
Cash, cash equivalents and restricted cash at end of period	$ 33,854	$ 52,419	$ 53,433

CONSOLIDATED STATEMENTS OF CA_2

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash and cash equivalents	$ 33,551	$ 52,056	$ 52,652
Total cash, cash equivalents, and restricted cash shown in consolidated statements of cash flows	33,854	52,419	53,433	$ 86,292
Prepaid expenses and other current assets
Restricted cash	0	60	260
Other long-term assets
Restricted cash	$ 303	$ 303	$ 521

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands		Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss	Treasury Stock	Noncontrolling Interests
Beginning balance (in shares) at Dec. 31, 2015	[1]		10,702,689
Beginning balance at Dec. 31, 2015	[1]	$ 112,040	$ 107	$ 894,715	$ (759,531)	$ (14,781)	$ (8,551)	$ 81
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income		(64,727)			(65,148)			421
Translation adjustment		(6,960)				(6,967)		7
Stock-based compensation expense		3,267		3,267
Vesting of restricted stock units/ awards (in shares)			40,495
Vesting of restricted stock units/awards		0
Purchase of treasury shares (in shares)			(155,304)
Purchase of treasury shares		(964)	$ (1)				(963)
Restricted stock cancelled for employee minimum income taxes (in shares)			(4,973)
Restricted stock cancelled for employee minimum income taxes		(22)		(22)
Issuance of stock for the ESPP (in shares)			4,100
Issuance of stock for the ESPP		23		23
Issuance of stock in bond exchange (in shares)			1,205,440
Issuance of stock in bond exchange		10,741	$ 12	1,215			9,514
Ending balance (in shares) at Dec. 31, 2016			11,792,447
Ending balance at Dec. 31, 2016		53,398	$ 118	899,198	(824,679)	(21,748)	0	509
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income		(29,377)			(30,242)			865
Translation adjustment		2,834				2,869		(35)
Dividend payment to noncontrolling interest		(100)						(100)
Stock-based compensation expense		$ 2,552		2,552
Exercise of stock options (in shares)		15,000	15,000
Exercise of stock options		$ 46		46
Vesting of restricted stock units/ awards (in shares)			115,576
Vesting of restricted stock units/awards		0	$ 1	(1)
Employee purchases of unregistered shares of common stock (in shares)			120,567
Employee purchases of unregistered shares of common stock		1,573	$ 1	1,572
Restricted stock cancelled for employee minimum income taxes (in shares)			(23,889)
Restricted stock cancelled for employee minimum income taxes		(120)		(120)
Ending balance (in shares) at Dec. 31, 2017			12,019,701
Ending balance at Dec. 31, 2017		30,806	$ 120	903,247	(854,921)	(18,879)	0	1,239
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income		(70,398)			(71,171)			773
Translation adjustment		(1,783)				(1,563)		(220)
Dividend payment to noncontrolling interest		(200)						(200)
Stock-based compensation expense		$ 3,337		3,337
Exercise of stock options (in shares)		70,086	70,086
Exercise of stock options		$ 214	$ 1	213
Vesting of restricted stock units/ awards (in shares)			151,852
Vesting of restricted stock units/awards		0	$ 1	(1)
Restricted stock cancelled for employee minimum income taxes (in shares)			(46,024)
Restricted stock cancelled for employee minimum income taxes		(1,151)		(1,151)
Public equity offering (in shares)			1,820,000
Public equity offering		46,999	$ 18	46,981
Ending balance (in shares) at Dec. 31, 2018			14,015,615
Ending balance at Dec. 31, 2018		$ 7,824	$ 140	$ 952,626	$ (926,092)	$ (20,442)	$ 0	$ 1,592
[1]	The figures for January 1, 2016, set forth in the tables above have been retroactively adjusted to reflect the one-for-fifteen reverse stock split completed on February 4, 2016.

CONSOLIDATED STATEMENTS OF ST_2

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (Parenthetical)	Feb. 04, 2016
Statement of Stockholders' Equity [Abstract]
Reverse stock split ratio of one share	0.066667

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies General Description and Principles of Consolidation ION Geophysical Corporation and its subsidiaries offer a full suite of services and products for seismic data acquisition and processing. The consolidated financial statements include the accounts of ION Geophysical Corporation and its majority-owned subsidiaries (collectively referred to as the “Company” or “ION”). Intercompany balances and transactions have been eliminated. Certain reclassifications were made to previously reported amounts in the consolidated financial statements and notes thereto to make them consistent with the current period presentation. Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates are made at discrete points in time based on relevant market information. These estimates may be subjective in nature and involve uncertainties and matters of judgment and, therefore, cannot be determined with precision. Areas involving significant estimates include, but are not limited to, accounts and unbilled receivables, inventory valuation, sales forecasts related to multi-client data libraries, goodwill and intangible asset valuation and deferred taxes. Actual results could materially differ from those estimates. Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. The Company places its temporary cash investments with high credit quality financial institutions. At times such investments may be in excess of the Federal Deposit Insurance Corporation insurance limit. At December 31, 2018 and 2017 , there was $0.3 million and $0.4 million , respectively, of long-term and short-term restricted cash used to secure standby and commercial letters of credit, which is included within “Other long-term assets” and “Prepaid expenses and other current assets” in the Consolidated Balance Sheets. Accounts and Unbilled Receivables Accounts and unbilled receivables are recorded at cost, less the related allowance for doubtful accounts. The Company considers current information and events regarding the customers’ ability to repay their obligations, such as the length of time the receivable balance is outstanding, the customers’ credit worthiness and historical experience. Unbilled receivables relate to revenues recognized on multi-client surveys, imaging services and devices equipment repairs on a proportionate basis, and on licensing of multi-client data libraries for which invoices have not yet been presented to the customer. Inventories Inventories are stated at the lower of cost (primarily first-in, first-out method) or net realizable value. The Company provides reserves for estimated obsolescence or excess inventory equal to the difference between cost of inventory and its estimated net realizable value based upon assumptions about future demand for the Company’s products, market conditions and the risk of obsolescence driven by new product introductions. Property, Plant, Equipment and Seismic Rental Equipment Property, plant, equipment and seismic rental equipment are stated at cost. Depreciation expense is provided straight-line over the following estimated useful lives: Years Machinery and equipment 3-7 Buildings 5-25 Seismic rental equipment 3-5 Leased equipment and other 3-10 Expenditures for renewals and betterments are capitalized; repairs and maintenance are charged to expense as incurred. The cost and accumulated depreciation of assets sold or otherwise disposed of are removed from the accounts and any gain or loss is reflected in operating expenses. The Company evaluates the recoverability of long-lived assets, including property, plant, equipment and seismic rental equipment, when indicators of impairment exist, relying on a number of factors including operating results, business plans, economic projections and anticipated future cash flows. Impairment in the carrying value of an asset held for use is recognized whenever anticipated future undiscounted cash flows from an asset are estimated to be less than its carrying value. The amount of the impairment recognized is the difference between the carrying value of the asset and its fair value. For 2018, the Company identified an indicator of impairment as it relates to its cable-based ocean bottom acquisition technologies. As a result, the Company recognized an impairment charge of $36.6 million . Multi-Client Data Library The multi-client data library consists of seismic surveys that are offered for licensing to customers on a non-exclusive basis. The capitalized costs include costs paid to third parties for the acquisition of data and related activities associated with the data creation activity and direct internal processing costs, such as salaries, benefits, computer-related expenses and other costs incurred for seismic data project design and management. For 2018 , 2017 and 2016 , the Company capitalized, as part of its multi-client data library, $11.9 million , $12.7 million and $6.6 million , respectively, of direct internal processing costs. At December 31, 2018 and 2017 , multi-client data library costs and accumulated amortization consisted of the following (in thousands): December 31, 2018 2017 Gross costs of multi-client data creation $ 972,309 $ 939,077 Less accumulated amortization (776,860 ) (727,872 ) Less impairments to multi-client data library (121,905 ) (121,905 ) Multi-client data library, net $ 73,544 $ 89,300 The Company’s method of amortizing the costs of an in-process multi-client data library (the period during which the seismic data is being acquired and/or processed, referred to as the “New Venture” phase) consists of determining the percentage of actual revenue recognized to the total estimated revenues (which includes both revenues estimated to be realized during the New Venture phase and estimated revenues from the licensing of the resulting “on-the-shelf” data survey) and multiplying that percentage by the total cost of the project (the sales forecast method). The Company considers a multi-client data survey to be complete when all work on the creation of the seismic data is finished and that data survey is available for licensing. Once a multi-client data survey is complete, the data survey is considered “on-the-shelf” and the Company’s method of amortization is then the greater of (i) the sales forecast method or (ii) the straight-line basis over a four-year period. The greater amount of amortization resulting from the sales forecast method or the straight-line amortization policy is applied on a cumulative basis at the individual survey level. Under this policy, the Company first records amortization using the sales forecast method. The cumulative amortization recorded for each survey is then compared with the cumulative straight-line amortization. The four-year period utilized in this cumulative comparison commences when the data survey is determined to be complete. If the cumulative straight-line amortization is higher for any specific survey, additional amortization expense is recorded, resulting in accumulated amortization being equal to the cumulative straight-line amortization for such survey. The Company has determined the amortization period of four years based upon its historical experience that indicates that the majority of its revenues from multi-client surveys are derived during the acquisition and processing phases and during four years subsequent to survey completion. The Company estimates the ultimate revenue expected to be derived from a particular seismic data survey over its estimated useful economic life to determine the costs to amortize, if greater than straight-line amortization. That estimate is made by the Company at the project’s initiation. For a completed multi-client survey, the Company reviews the estimate quarterly. If during any such review, the Company determines that the ultimate revenue for a survey is expected to be materially more or less than the original estimate of ultimate revenue for such survey, the Company decreases or increases (as the case may be) the amortization rate attributable to the future revenue from such survey. In addition, in connection with such reviews, the Company evaluates the recoverability of the multi-client data library, and, if required, records an impairment charge with respect to such data. Equity Method Investment The Company determined that INOVA Geophysical is a variable interest entity because the Company’s voting rights with respect to INOVA Geophysical are not proportionate to its ownership interest and substantially all of INOVA Geophysical’s activities are conducted on behalf of the Company and BGP, a related party to the Company. The Company is not the primary beneficiary of INOVA Geophysical because it does not have the power to direct the activities of INOVA Geophysical that most significantly impact its economic performance. Accordingly, the Company does not consolidate INOVA Geophysical, but instead accounts for INOVA Geophysical using the equity method of accounting. Under this method, an investment is carried at the acquisition cost, plus the Company’s equity in undistributed earnings or losses since acquisition, less distributions received. At December 31, 2014, the Company fully impaired its investment in INOVA reducing its equity investment in INOVA and its share of INOVA’s accumulated other comprehensive loss, both to zero . As of December 31, 2018, the carrying value of this investment remains zero . The Company no longer records its equity in losses or earnings and has no obligation, implicit or explicit, to fund any expenses of INOVA Geophysical. Noncontrolling Interests The Company has non-redeemable noncontrolling interests. Non-redeemable noncontrolling interests in majority-owned affiliates are reported as a separate component of equity in “Noncontrolling interests” in the Consolidated Balance Sheets. Net income attributable to noncontrolling interests is stated separately in the Consolidated Statements of Operations. The activity for this noncontrolling interest relates to proprietary processing projects in Brazil. Goodwill Goodwill is allocated to reporting units, which are either the operating segment or one reporting level below the operating segment. For purposes of performing the impairment test for goodwill, the Company established the following reporting units: E&P Technology & Services, Optimization Software & Services and Devices. The Company is required to evaluate the carrying value of its goodwill at least annually for impairment, or more frequently if facts and circumstances indicate that it is more likely than not impairment has occurred. The Company formally evaluates the carrying value of its goodwill for impairment as of December 31 for each of its reporting units. The Company first performs a qualitative assessment by evaluating relevant events or circumstances to determine whether it is more likely than not that the fair value of a reporting unit exceeds its carrying amount. If the Company is unable to conclude qualitatively that it is more likely than not that a reporting unit’s fair value exceeds its carrying value, then it will use a two-step quantitative assessment of the fair value of a reporting unit. To determine the fair value of these reporting units, the Company uses a discounted future returns valuation model, which includes a variety of level 3 inputs. The key inputs for the model include the operational three -year forecast for the Company and the then-current market discount factor. Additionally, the Company compares the sum of the estimated fair values of the individual reporting units less consolidated debt to the Company’s overall market capitalization as reflected by the Company’s stock price. If the carrying value of a reporting unit that includes goodwill is determined to be more than the fair value of the reporting unit, there exists the possibility of impairment of goodwill. An impairment loss of goodwill is measured in two steps by first allocating the fair value of the reporting unit to net assets and liabilities including recorded and unrecorded intangible assets to determine the implied carrying value of goodwill. The next step is to measure the difference between the carrying value of goodwill and the implied carrying value of goodwill, and, if the implied carrying value of goodwill is less than the carrying value of goodwill, an impairment loss is recorded equal to the difference. See further discussion below at Footnote 11 “ Goodwill .” Revenue From Contracts With Customers On January 1, 2018, the Company adopted Accounting Standards Codification Topic 606 - “Revenue from Contracts with Customers” and all the related amendments (“ASC 606”), using the modified retrospective method. This standard applies to all contracts with customers, except for contracts that are within the scope of other standards, such as leases, insurance, collaborative arrangements and financial instruments. The adoption of ASC 606 did not have a material impact on the Consolidated Balance Sheets or Consolidated Statements of Operations for any of our reporting segments. See further discussion below at Footnote 3 “ Revenue from Contracts with Customers .” Research, Development and Engineering Research, development and engineering costs primarily relate to activities that are designed to improve the quality of the subsurface image and overall acquisition economics of the Company’s customers. The costs associated with these activities are expensed as incurred. These costs include prototype material and field testing expenses, along with the related salaries and stock-based compensation, facility costs, consulting fees, tools and equipment usage and other miscellaneous expenses associated with these activities. Stock-Based Compensation The Company accounts for all stock-based payment awards issued to employees and directors, including employee stock options, restricted stocks units, restricted stocks and stock appreciation rights under the provisions of ASC 718 “Compensation – Stock Compensation ” (“ASC 718”). The Company estimates the value of stock-based payment awards on the date of grant using an option pricing model such as Black-Scholes or Monte Carlo simulation. The determination of the fair value of stock-based payment awards is affected by the Company’s stock price as well as assumptions regarding a number of subjective variables. These variables include, but are not limited to, expected stock price volatility over the term of the awards, actual and projected stock-based instrument exercise behaviors, risk-free interest rate and expected dividends. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. The Company recognizes stock-based compensation expense on the straight-line basis over the requisite service period of each award that are ultimately expected to vest. Income Taxes Income taxes are accounted for under the liability method. Deferred income tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, including operating loss and tax credit carryforwards. Deferred income tax assets and liabilities are measured using enacted tax rates expected to apply in the years in which those temporary differences are expected to be recovered or settled. The Company records a valuation allowance when it is more likely than not that all or a portion of deferred tax assets will not be realized (see Footnote 7 “ Income Taxes ”). The effect on deferred income tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. Debt Issuance Costs The Company presents debt issuance costs related to a debt liability as a direct deduction from the carrying amount of that debt liability on the Consolidated Balance Sheets and amortizes such costs using the effective interest method whereas debt issuance costs related to line of credit arrangement is presented within “Other assets” on the Consolidated Balance Sheets and amortized ratably over the term of the line of credit arrangement, regardless of whether there are any outstanding borrowings on the line of credit arrangement. Foreign Currency Gains and Losses Assets and liabilities of the Company’s subsidiaries operating outside the United States that have a functional currency other than the U.S. dollar have been translated to U.S. dollars using the exchange rate in effect at the balance sheet date. Results of foreign operations have been translated using the average exchange rate during the periods of operation. Resulting translation adjustments have been recorded as a component of Accumulated Other Comprehensive Loss . Foreign currency transaction gains and losses, as they occur, are included in “Other income (expense), net” on the Consolidated Statements of Operations. Total foreign currency transaction losses were $0.4 million , $1.6 million and $3.3 million for 2018 , 2017 and 2016 , respectively. Concentration of Foreign Sales Risk The majority of the Company’s foreign sales are denominated in U.S. dollars. For 2018 , 2017 and 2016 , international sales comprised 75% , 76% and 78% , respectively, of total net revenues. Since 2008, global economic problems and uncertainties have generally increased in scope and nature. The volatility in oil prices have continued to impact the global market throughout 2018. To the extent that world events or economic conditions negatively affect the Company’s future sales to customers in many regions of the world, as well as the collectability of the Company’s existing receivables, the Company’s future results of operations, liquidity and financial condition would be adversely affected.

Segment and Geographic Informat

Segment and Geographic Information	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Segment and Geographic Information	Segment and Geographic Information During the first quarter of 2019, the Company consolidated its operating segments from three into two , eliminating the separate presentation of Ocean Bottom Integrated Technologies segment. This consolidation aligns with our asset light business model and evolved strategy to commercialize components of the Company’s next generation ocean bottom nodal system, 4Sea, instead of operating a crew. The Company is offering 4Sea components more broadly to the growing number of OBS service providers under recurring revenue commercial strategies that will enable it to share in the value the technology delivers. The Company may also license the right to manufacture and use the 4Sea nodal technology to a service provider on a value-based pricing model, such as a royalty stream. Revenues from 4Sea would be recognized through the relevant segment, either E&P Technology & Services or Operations Optimization. Accordingly, the Company evaluates and reviews its results based on two business segments: E&P Technology & Services and Operations Optimization. The segments represent components of the Company for which separate financial information is available that is utilized on a regular basis by the Chief Operating Decision Maker in determining how to allocate resources and evaluate performance. The Company measures segment operating results based on income (loss) from operations. Previously reported segment information has been retrospectively revised throughout the consolidated financial statements, as applicable, for all periods presented to reflect the changes in the Company’s reporting segments. A summary of segment information follows (in thousands): Years Ended December 31, 2018 2017 2016 Net revenues: E&P Technology & Services: New Venture $ 69,685 $ 100,824 $ 27,362 Data Library 47,095 40,016 39,989 Total multi-client revenues 116,780 140,840 67,351 Imaging Services 19,740 16,409 25,538 Total $ 136,520 $ 157,249 $ 92,889 Operations Optimization: Devices $ 22,396 $ 23,610 $ 26,746 Optimization Software & Services 21,129 16,695 16,756 Total $ 43,525 $ 40,305 $ 43,502 Other $ — $ — $ 36,417 (a) Total $ 180,045 $ 197,554 $ 172,808 Gross profit (loss): E&P Technology & Services $ 43,369 $ 65,196 $ 4,708 Operations Optimization 22,293 20,076 21,745 Segment gross profit 65,662 85,272 26,453 Other (b) (6,042 ) (9,633 ) 9,579 Total $ 59,620 $ 75,639 $ 36,032 Gross margin: E&P Technology & Services 32 % 41 % 5 % Operations Optimization 51 % 50 % 50 % Segment gross margin 36 % 43 % 15 % Other (3 )% (5 )% 6 % Total 33 % 38 % 21 % Income (loss) from operations: E&P Technology & Services $ 21,758 $ 42,505 $ (16,446 ) Operations Optimization 7,295 8,022 9,652 Support and other (c) (83,325 ) (d) (59,226 ) (36,377 ) Loss from operations (54,272 ) (8,699 ) (43,171 ) Interest expense, net (12,972 ) (16,709 ) (18,485 ) Other income (expense), net (436 ) (3,945 ) 1,350 Loss before income taxes $ (67,680 ) $ (29,353 ) $ (60,306 ) (a) Relates to revenues of the previously reported Ocean Bottom Integrated Technologies segment. (b) Relates to gross profit (loss) of previously reported Ocean Bottom Integrated Technologies segment. (c) Includes loss from operations of previously reported Ocean Bottom Integrated Technologies segment of $47.6 million , $16.3 million and $1.8 million for the years ended December 31, 2018, 2017 and 2016, respectively, which includes item (b) above and operating expenses of $41.6 million , $6.7 million and $11.3 million for the years ended December 31, 2018, 2017 and 2016. (d) Includes a charge of $36.6 million to write-down the cable-based ocean bottom acquisition technologies associated with the previously reported Ocean Bottom Integrated Technologies segment. This impairment relates to property, plant, equipment and seismic rental equipment of $21.3 million within the Operations Optimization segment and $15.3 million within the previously reported Ocean Bottom Integrated Technologies segment. Years Ended December 31, 2018 2017 2016 Depreciation and amortization (including multi-client data library): E&P Technology & Services $ 51,673 $ 53,663 $ 44,100 Operations Optimization 995 1,349 1,780 Support and other (a) 5,083 8,682 9,430 Total $ 57,751 $ 63,694 $ 55,310 (a) Includes depreciation and amortization of previously reported Ocean Bottom Integrated Technologies segment of $4.2 million , $7.0 million and $7.5 million for the year ended December 31, 2018, 2017 and 2016, respectively. December 31, 2018 2017 Total assets: E&P Technology & Services $ 165,132 $ 156,555 Operations Optimization 51,783 74,361 Support and other (a) 27,834 70,153 Total $ 244,749 (b) $ 301,069 (a) Includes total assets of previously reported Ocean Bottom Integrated Technologies segment of $1.2 million and $20.8 million for the year ended December 31, 2018 and 2017, respectively. (b) Balance is net of impairment charge of $36.6 million related to the cable-based ocean bottom acquisition technologies. A summary of total assets by geographic area follows (in thousands): December 31, 2018 2017 North America $ 86,614 $ 116,598 Latin America 69,418 55,661 Middle East 52,037 70,308 Europe 31,566 51,876 Other 5,114 6,626 Total $ 244,749 $ 301,069 A summary of property, plant, equipment and seismic equipment less accumulated depreciation and impairment by geographic area follows (in thousands): December 31, 2018 2017 North America $ 11,663 $ 10,609 Europe 1,140 20,725 Latin America 143 170 Middle East 36 20,543 Other 59 106 Total $ 13,041 (a) $ 52,153 (a) Balance is net of impairment charge of $36.6 million related to the cable-based ocean bottom acquisition technologies. Intersegment sales are insignificant for all periods presented. Support and other assets include all assets specifically related to support personnel and operation and a majority of cash and cash equivalents. Depreciation and amortization expense is allocated to segments based upon use of the underlying assets. A summary of net revenues by geographic area follows (in thousands): Years Ended December 31, 2018 2017 2016 Latin America $ 68,871 $ 68,241 $ 24,090 North America 44,474 48,120 38,005 Europe 31,077 44,930 41,674 Asia Pacific 17,817 18,896 16,226 Africa 10,837 6,837 41,417 Middle East 5,526 2,308 9,467 Commonwealth of Independent States 1,443 8,222 1,929 Total $ 180,045 $ 197,554 $ 172,808 Net revenues are attributed to geographic areas on the basis of the ultimate destination of the equipment or service, if known, or the geographic area imaging services are provided. If the ultimate destination of such equipment is not known, net revenues are attributed to the geographic area of initial shipment.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	Revenue from Contracts with Customers The Company derives revenue from the sale or license of (i) multi-client and proprietary data, imaging services and E&P Advisors consulting services within its E&P Technology & Services segment; (ii) seismic data acquisition systems and other seismic equipment and (iii) seismic command and control software systems and software solutions for operations management within its Operations Optimization segment. All revenues of the E&P Technology & Services segment and the services component of revenues for the Optimization Software & Services group as part of the Operations Optimization segment are classified as services revenues. All other revenues are classified as product revenues. The Company uses a five-step model to determine proper revenue recognition from customer contracts. Revenue is recognized when (i) a contract is approved by all parties; (ii) the goods or services promised in the contract are identified; (iii) the consideration the Company expects to receive in exchange for the goods or services promised is determined; (iv) the consideration is allocated to the goods and services in the contract; and (v) control of the promised goods or services is transferred to the customer. The Company does not disclose the value of contractual future performance obligations such as backlog with an original expected length of one year or less within the footnotes. Multi-client and Proprietary Surveys, Imaging Services and E&P Advisors Services - As multi-client seismic surveys are being designed, acquired or processed (the “New Venture” phase), the Company enters into non-exclusive licensing arrangements with its customers, who pre-fund or underwrite these programs in part. License revenues from these surveys are recognized during the New Venture phase as the seismic data is acquired and/or processed on a proportionate basis as work is performed and control is transferred to the customer. Under this method, the Company recognizes revenue based upon quantifiable measures of progress, such as kilometers acquired or surveys of performance completed to date. Upon completion of a multi-client seismic survey, it is considered “on-the-shelf,” and licenses to the survey data are granted to customers on a non-exclusive basis. The Company also performs seismic surveys, imaging and other services under contracts with specific customers, whereby the seismic data is owned by those customers. The Company recognizes revenue as the seismic data is acquired and/or processed on a proportionate basis as work is performed. The Company uses quantifiable measures of progress consistent with its multi-client seismic surveys. Acquisition Systems and Other Seismic Equipment - For sales of seismic data acquisition systems and other seismic equipment, the Company recognizes revenue when control of the goods has transferred to the customer. Transfer of control generally occurs when (i) the Company has a present right to payment; (ii) the customer has legal title to the asset; (iii) the Company has transferred physical possession of the asset; and (iv) the customer has significant rewards of ownership; or (v) the customer has accepted the asset. Software - Licenses for the Company’s navigation, survey design and quality control software systems provide the customer with a right to use the software. The Company offers usage-based licenses under which it receives a monthly fee based on the number of vessels and licenses used. For these usage-based licenses, revenue is recognized as the performance obligations are performed over the contract term, which is generally two to five years. In addition to usage-based licenses, the Company offers perpetual software licenses as it exists when made available to the customer. Revenue from these licenses is recognized upfront at the point in time when the software is made available to the customer. These arrangements generally include the Company providing related services, such as training courses, engineering services and annual software maintenance. The Company allocates consideration to each element of the arrangement based upon directly observable or estimated standalone selling prices. Revenue is recognized for these services as control transfers to the customer over time. Revenue by Segment and Geographic Area See Footnote 2 “Segment Information” of Footnotes to Consolidated Financial Statements for revenue by segment and revenue by geographic area for the years ended December 31, 2018 , 2017 and 2016 . In 2018 , the Company had two customers with sales that each exceeded 10% of the consolidated net revenues. Revenues related to these customers are included within the E&P Technology & Services segment. In 2017 , the Company had one customer with sales that exceeded 10% of the consolidated net revenues and revenues related to this customer are included within the E&P Technology & Services segment. No single customer represented 10% or more of the consolidated net revenues for 2016 . Unbilled Receivables Unbilled receivables relate to revenues recognized on multi-client surveys, imaging services and Devices equipment repairs on a proportionate basis, and on licensing of multi-client data libraries for which invoices have not yet been presented to the customer. The following table is a summary of unbilled receivables (in thousands): December 31, 2018 2017 New Venture $ 38,430 $ 33,183 Imaging Services 5,075 4,121 Devices 527 — Total $ 44,032 $ 37,304 The changes in unbilled receivables were as follows (in thousands): Unbilled receivables at December 31, 2017 $ 37,304 Recognition of unbilled receivables 153,611 Revenues billed to customers (146,883 ) Unbilled receivables at December 31, 2018 $ 44,032 Deferred Revenue Billing practices are governed by the terms of each contract based upon achievement of milestones or pre-agreed schedules. Billing does not necessarily correlate with revenue recognized on a proportionate basis as work is performed and control is transferred to the customer. Deferred revenue represents cash received in excess of revenue not yet recognized as of the reporting period, but will be recognized in future periods. The following table is a summary of deferred revenues (in thousands): December 31, 2018 2017 New Venture $ 5,797 $ 6,548 Imaging Services 307 676 Devices 626 633 Optimization Software & Services 980 1,053 Total $ 7,710 $ 8,910 The changes in deferred revenues were as follows (in thousands): Deferred revenue at December 31, 2017 $ 8,910 Cash collected in excess of revenue recognized 25,234 Recognition of deferred revenue (a) (26,434 ) Deferred revenue at December 31, 2018 $ 7,710 (a) The majority of deferred revenue recognized relates to Company’s Ventures group. The Company expects to recognize all deferred revenue within the next 12 months.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2018
Accounting Changes and Error Corrections [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-2, “ Leases (Topic 842)” which introduces the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous guidance. The guidance will be effective for annual reporting periods beginning after December 15, 2018 and interim periods within those fiscal years with early adoption permitted. The Company will adopt ASU 2016-2 on January 1, 2019 using the modified retrospective method. The Company has completed its evaluation of operating leases related to offices, processing centers, warehouse spaces and, to a lesser extent, certain equipment. The Company expects the adoption of the standard will result in approximately $50 million to $60 million in right-of-use assets and lease obligations on the Consolidated Balance Sheets. The Company expects the Income Statement recognition to appear similar to its current methodology. The Company will elect the practical expedients upon transition which will retain the lease classification for leases and any unamortized initial direct costs that existed prior to the adoption of the standard. On January 1, 2018, the Company adopted ASC 606 and all the related amendments using the modified retrospective method. The adoption did not have a material impact to the Company’s revenue recognition policy under the previous standard and adoption of the new standard did not result in an adjustment to the Company’s beginning retained earnings balance. On January 1, 2018, the Company adopted ASU 2016-18, Statement of Cash Flows “ Restricted Cash (a consensus of the FASB Emerging Issues Task Force) ”, using a retrospective transition method to each period presented. The new standard no longer requires the Company to present transfers between cash and cash equivalents and restricted cash in the statements of cash flows. Adoption of the new standard resulted in a decrease of $0.4 million and $0.6 million in net cash provided by operating activities as previously reported for the years ended December 31, 2017 and 2016, respectively. See the Consolidated Statements of Cash Flows above which includes a reconciliation of cash and cash equivalents to total cash, cash equivalents, and restricted cash. In June 2016, the FASB issued ASU No. 2016-13, “ Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments.” The guidance will replace the incurred loss impairment methodology under 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 guidance is effective for public companies for interim and annual periods beginning after December 15, 2019, with early adoption permitted for interim and annual periods beginning after December 15, 2018. The Company is in the initial stages of evaluating the impact of this standard on the Consolidated Financial Statements.

Long-term Debt and Lease Obliga

Long-term Debt and Lease Obligations	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Long-term Debt and Lease Obligations	Long-term Debt and Lease Obligations The following is a summary of long-term debt and lease obligation (in thousands): December 31, 2018 2017 Senior secured second-priority lien notes (maturing December 15, 2021) $ 120,569 $ 120,569 Senior secured third-priority lien notes (redeemed March 26, 2018) — 28,497 Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a) — 10,000 Equipment capital leases 2,938 279 Other debt 1,159 1,382 Costs associated with issuances of debt (2,925 ) (3,983 ) Total 121,741 156,744 Current portion of long-term debt and lease obligations (2,228 ) (40,024 ) Non-current portion of long-term debt and lease obligations $ 119,513 $ 116,720 (a) The maturity of the revolving credit facility will accelerate to December 15, 2021 if the Company is unable to repay or extend the maturity of the Second Lien Notes. Revolving Credit Facility On August 16, 2018, ION and its material U.S. subsidiaries; GX Technology Corporation, ION Exploration Products (U.S.A) Inc. and I/O Marine Systems Inc. (the “Material U.S. Subsidiaries”), along with GX Geoscience Corporation, S. de R.L. de C.V., a limited liability company (Sociedad de Responsibilidad Limitada de Capital Variable) organized under the laws of Mexico, and a subsidiary of the Company (the “Mexican Subsidiary”), (the Material U.S. Subsidiaries and the Mexican Subsidiary are collectively, the “Subsidiary Borrowers”, together with ION Geophysical Corporation are the “Borrowers”), the financial institutions party thereto, as lenders, and PNC Bank, National Association (“PNC”), as agent for the lenders, entered into that certain Third Amendment and Joinder to Revolving Credit and Security Agreement (the “Third Amendment”), amending the Revolving Credit and Security Agreement, dated as of August 22, 2014 (as previously amended by the First Amendment to Revolving Credit and Security Agreement, dated as of August 4, 2015 and the Second Amendment to Revolving Credit and Security Agreement, dated as of April 28, 2016, the “Credit Agreement”). The Credit Agreement, as amended by the First Amendment, the Second Amendment and the Third Amendment is herein called, the “Credit Facility”). The Credit Facility is available to provide for the Borrowers’ general corporate needs, including working capital requirements, capital expenditures, surety deposits and acquisition financing. The Third Amendment amends the Credit Agreement to, among other things: • extend the maturity date of the Credit Facility by approximately four years (from August 22, 2019 to August 16, 2023), subject to the retirement or extension of the maturity date of the Second Lien Notes, as defined below, which mature on December 15, 2021; • increase the maximum revolver amount by $10 million (from $40 million to $50 million ); • increase the borrowing base percentage of the net orderly liquidation value as it relates to the multi-client data library (not to exceed $28.5 million , up from the previous maximum of $15 million for the multi-client data library component); • include the eligible billed receivables of the Mexican Subsidiary up to a maximum of $5 million in the borrowing base calculation and joins the Mexican Subsidiary as a borrower thereunder (with a maximum exposure of $5 million ) and require the equity and assets of the Mexican Subsidiary to be pledged to secure obligations under the Credit Facility; • modify the interest rate such that the maximum interest rate remains consistent with the fixed interest rate prior to the Third Amendment (that is, 3.00% per annum for domestic rate loans and 4.00% per annum for LIBOR rate loans), but now lowers the range down to a minimum interest rate of 2.00% for domestic rate loans and 3.00% for LIBOR rate loans based on a leverage ratio for the preceding four-quarter period; • decrease the minimum excess borrowing availability threshold which (if the Borrowers have minimum excess borrowing availability below any such threshold) triggers the agent’s right to exercise dominion over cash and deposit accounts; and • modify the trigger required to test for compliance with the fixed charge coverage ratio, which is further described below. The maximum amount under the Credit Facility is the lesser of $50.0 million or a monthly borrowing base. The borrowing base under the Credit Facility will increase or decrease monthly using a formula based on certain eligible receivables, eligible inventory and other amounts, including a percentage of the net orderly liquidation value of the Borrowers’ multi-client data library. As of December 31, 2018 , the borrowing base under the Credit Facility was $41.9 million and there was no outstanding indebtedness under the Credit Facility. The obligations of Borrowers under the Credit Facility are secured by a first-priority security interest in 100% of the stock of the Subsidiary Borrowers and 65% of the equity interest in ION International Holdings L.P. and by substantially all other assets of the Borrowers. However, the first-priority security interest in the other assets of the Mexican Subsidiary is limited to a maximum exposure of $5.0 million . The Credit Facility contains covenants that, among other things, limit or prohibit the Borrowers, subject to certain exceptions and qualifications, from incurring additional indebtedness in excess of permitted indebtedness (including capital lease obligations), repurchasing equity, paying dividends or distributions, granting or incurring additional liens on the Borrowers’ properties, pledging shares of the Borrowers’ subsidiaries, entering into certain merger transactions, entering into transactions with the Company’s affiliates, making certain sales or other dispositions of the Borrowers’ assets, making certain investments, acquiring other businesses and entering into sale-leaseback transactions with respect to the Borrowers’ property. The Credit Facility, requires that ION and the Subsidiary Borrowers maintain a minimum fixed charge coverage ratio of 1.1 to 1.0 as of the end of each fiscal quarter during the existence of a covenant testing trigger event. The fixed charge coverage ratio is defined as the ratio of (i) ION’s EBITDA, minus unfunded capital expenditures made during the relevant period, minus distributions (including tax distributions) and dividends made during the relevant period, minus cash taxes paid during the relevant period, to (ii) certain debt payments made during the relevant period. A covenant testing trigger event occurs upon (a) the occurrence and continuance of an event of default under the Credit Facility or (b) by a two-step process based on (i) a minimum excess borrowing availability threshold (excess borrowing availability less than $6.25 million for five consecutive business days or $5.0 million on any given business day, and (ii) the Borrowers’ unencumbered cash maintained in a PNC deposit account is less that the Borrowers’ then outstanding obligations. Prior to the Third Amendment, the test covenant compliance was tied to a total liquidity measure (liquidity less than $7.5 million for five consecutive days or $6.5 million on any given day). As of December 31, 2018 , the Company was in compliance with all of the covenants under the Credit Facility. The Credit Facility, as amended, contains customary event of default provisions (including a “change of control” event affecting ION), the occurrence of which could lead to an acceleration of the Company’s obligations under the Credit Facility. Senior Secured Notes As of December 31, 2018, ION Geophysical Corporation’s 9.125% Senior Secured Second Priority Notes due December 2021 (the “Second Lien Notes”) had an outstanding principal amount of $120.6 million . Prior to its early redemption, ION Geophysical Corporation’s 8.125% Senior Secured Second-Priority Notes due May 2018 (the “Third Lien Notes”) had an aggregate principal amount of $28.5 million . In March 2018, ION Geophysical Corporation obtained consent from a majority of the Second Lien Notes holders and from PNC to redeem, in full, the Third Lien Notes prior to their stated maturity. On March 26, 2018, ION Geophysical Corporation redeemed the Third Lien Notes by paying the then outstanding principal amount, plus all accrued and unpaid interest through the redemption date. The Second Lien Notes remain outstanding and are senior secured second-priority obligations guaranteed by the Material U.S. Subsidiaries and the Mexican Subsidiary (each as defined above and herein below, with the reference to the Second Lien Notes, the “Guarantors”). Interest on the Second Lien Notes accrues at the rate of 9.125% per annum and is payable semiannually in arrears on June 15 and December 15 of each year during their term, except that the interest payment otherwise payable on June 15, 2021 will be payable on December 15, 2021. The April 2016 indenture governing the Second Lien Notes contains certain covenants that, among other things, limits or prohibits ION Geophysical Corporation’s ability and the ability of its restricted subsidiaries to take certain actions or permit certain conditions to exist during the term of the Second Lien Notes, including among other things, incurring additional indebtedness, creating liens, paying dividends and making other distributions in respect of ION Geophysical Corporation’s capital stock, redeeming ION Geophysical Corporation’s capital stock, making investments or certain other restricted payments, selling certain kinds of assets, entering into transactions with affiliates, and effecting mergers or consolidations. These and other restrictive covenants contained in the Second Lien Notes Indenture are subject to certain exceptions and qualifications. All of ION Geophysical Corporation’s subsidiaries are currently restricted subsidiaries. As of December 31, 2018 , the Company was in compliance with the covenants with respect to the Second Lien Notes. On or after December 15, 2019, the Company may on one or more occasions redeem all or a part of the Second Lien Notes at the redemption prices set forth below, plus accrued and unpaid interest and special interest, if any, on the Second Lien Notes redeemed during the twelve-month period beginning on December 15th of the years indicated below: Date Percentage 2019 105.500% 2020 103.500% 2021 and thereafter 100.000% Equipment Capital Leases The Company has entered into capital leases that are due in installments for the purpose of financing the purchase of computer equipment through 2021. Interest accrues under these leases at rates from 4.3% to 8.7% per annum, and the leases are collateralized by liens on the computer equipment. The assets are amortized over the lesser of their related lease terms or their estimated productive lives and such charges are reflected within depreciation expense. A summary of future principal obligations under long-term debt and equipment capital lease obligations follows (in thousands): Years Ending December 31, Short-Term and Long-Term Debt Capital Lease Obligations Other Financing Total 2019 $ — $ 1,069 1,159 $ 2,228 2020 — 1,135 — 1,135 2021 120,569 734 — 121,303 Total $ 120,569 $ 2,938 $ 1,159 $ 124,666

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The sources of income (loss) before income taxes are as follows (in thousands): Years Ended December 31, 2018 2017 2016 Domestic $ (59,212 ) $ (12,487 ) $ (41,246 ) Foreign (8,468 ) (16,866 ) (19,060 ) Total $ (67,680 ) $ (29,353 ) $ (60,306 ) Components of income taxes are as follows (in thousands): Years Ended December 31, 2018 2017 2016 Current: Federal $ — $ (166 ) $ — State and local 65 116 28 Foreign 8,905 5,494 5,574 Deferred: Federal (346 ) (1,263 ) — Foreign (5,906 ) (4,157 ) (1,181 ) Total income tax expense $ 2,718 $ 24 $ 4,421 A reconciliation of the expected income tax expense on income (loss) before income taxes using the statutory federal income tax rate of 21% for 2018 and 35% for 2017 and 2016 to income tax expense follows (in thousands): Years Ended December 31, 2018 2017 2016 Expected income tax expense at 21% for 2018 and 35% for 2017 and 2016 $ (14,213 ) $ (10,274 ) $ (21,107 ) Foreign tax rate differential 74 (2,914 ) 5,932 Foreign tax differences 4,703 (5,610 ) (4,828 ) Global intangible low tax income inclusion 3,443 — — State and local taxes 65 116 28 Nondeductible expenses 1,604 4,308 (259 ) Change in U.S. tax rate — 77,410 — Expired capital loss — 1,114 1,321 Valuation allowance: Valuation allowance on expiring capital losses — (1,114 ) (1,321 ) Valuation allowance on operations 7,042 (63,012 ) 24,655 Total income tax expense $ 2,718 $ 24 $ 4,421 As a result of passage of the Tax Cut and Jobs Act (the “Act”) in December 2017, the Company’s U.S. deferred tax assets, liabilities, and associated valuation allowance as of December 31, 2018 and 2017 have been re-measured at the new U.S. federal tax rate of 21%. The tax effects of the cumulative temporary differences resulting in the net deferred income tax asset (liability) are as follows (in thousands): December 31, 2018 2017 Deferred income tax assets: Accrued expenses $ 1,126 $ 1,976 Allowance accounts 6,415 2,960 Net operating loss carryforward 96,854 87,705 Equity method investment 35,292 35,292 Original issue discount 8,073 9,624 Interest limitation 5,845 — Basis in identified intangibles 4,146 9,408 Tax credit carryforwards 5,345 6,929 Contingency accrual — 788 Other 4,600 4,035 Total deferred income tax asset 167,696 158,717 Valuation allowance (160,505 ) (153,463 ) Net deferred income tax asset 7,191 5,254 Deferred income tax liabilities: Unbilled receivables — (3,501 ) Total deferred income tax asset, net $ 7,191 $ 1,753 As of December 31, 2018 , the Company has a valuation allowance on substantially all net U.S. deferred tax assets. The valuation allowance was released in 2017 with respect to refundable U.S. alternative minimum tax (“AMT”) credits that will be realized as a result of provisions in the Act. A valuation allowance is established or maintained when it is “more likely than not” that all or a portion of deferred tax assets will not be realized. The Company will continue to record a valuation allowance for the substantial majority of its deferred tax assets until there is sufficient evidence to warrant reversal. At December 31, 2018 , the Company had U.S. net operating loss carryforwards of approximately $274.4 million , expiring in 2034 and beyond, and net operating loss carryforwards outside of the U.S. of approximately $153.1 million , the majority of which expires beyond 2025. As of December 31, 2018 , the Company has approximately $0.4 million of unrecognized tax benefits and does not expect to recognize any significant increases in unrecognized tax benefits during the next twelve-month period. Interest and penalties, if any, related to unrecognized tax benefits are recorded in income tax expense. During 2018 , 2017 and 2016 , the aggregate changes in the Company’s total gross amount of unrecognized tax benefits are summarized as follows (in thousands): Years Ended December 31, 2018 2017 2016 Beginning balance $ 447 $ 1,299 $ 1,250 Increases in unrecognized tax benefits – current year positions — 59 49 Decreases in unrecognized tax benefits – prior year position — (911 ) — Ending balance $ 447 $ 447 $ 1,299 The Company’s U.S. federal tax returns for 2015 and subsequent years remain subject to examination by tax authorities. The Company is no longer subject to Internal Revenue Service (“IRS”) examination for periods prior to 2015, although carryforward attributes that were generated prior to 2015 may still be adjusted upon examination by the IRS if they either have been or will be used in a future period. In the Company’s foreign tax jurisdictions, tax returns for 2012 and subsequent years generally remain open to examination. As of December 31, 2018 , the Company considered the outside book-over-tax basis difference in its foreign subsidiaries to be in the amount of approximately $85.0 million . United States income taxes have not been provided on this basis difference as it is the Company’s intention to reinvest the undistributed earnings of its foreign subsidiaries to the extent they cannot be remitted to the United States without incurring incremental tax as provided in the Act.

Net Income (Loss) per Common Sh

Net Income (Loss) per Common Share	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Net Income (Loss) per Common Share	Net Income (Loss) per Common Share Basic net income (loss) per common share is computed by dividing net income (loss) applicable to common shares by the weighted average number of common shares outstanding during the period. Diluted net income (loss) per common share is determined based on the assumption that dilutive restricted stock and restricted stock unit awards have vested and outstanding dilutive stock options have been exercised and the aggregate proceeds were used to reacquire common stock using the average price of such common stock for the period. The total number of shares issuable under anti-dilutive options at December 31, 2018 , 2017 and 2016 were 785,890 , 890,341 and 847,635 , respectively. All outstanding stock options for the twelve months ended December 31, 2018 , 2017 and 2016 were anti-dilutive.

Legal Matters

Legal Matters	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Legal Matters	Legal Matters WesternGeco A more thorough treatment of history of this litigation is set forth above in Item 1.A, “Risk Factors”. As noted in that section, in 2014, because a jury found that we infringed four WesternGeco patents, the United States District Court for the Southern District of Texas (the “District Court”) entered a Final Judgment against us in the amount of $123.8 million ( $12.5 million in reasonable royalties, $93.4 million in lost profits, $10.9 million in pre-judgment interest on lost profits, and $9.4 million in supplemental damages). In 2015, the United States Court of Appeals for the Federal Circuit in Washington, D.C. (the “Court of Appeals”) reversed, in part, the District Court, holding that the lost profits, which were attributable to foreign seismic surveys, were not available to WesternGeco under the Patent Act. The Company had recorded a loss contingency accrual of $123.8 million because of the District Court’s ruling. As a result of the reversal by the Court of Appeals, the Company reduced the loss contingency accrual to $22.0 million . On February 26, 2016, WesternGeco appealed the Court of Appeals’ decision to the Supreme Court, as to both lost profits and “enhanced” damages (damages which are available for willful infringement, and which neither the District Court nor the Trial Court awarded). On June 20, 2016, the Supreme Court vacated the Court of Appeals’ ruling, although it did not address lost profits at that time. Rather, in light of changes in case law regarding the standard of proof for willfulness in patent infringement, the Supreme Court remanded the case to the Court of Appeals for a determination of whether enhanced damages were appropriate. On November 14, 2016, the District Court ordered our sureties to pay principal and interest on the royalty damages previously awarded. On November 25, 2016, the Company paid WesternGeco the $20.8 million due pursuant to the order, and it reduced its loss contingency accrual to zero . On March 14, 2017, the District Court held a hearing on whether impose additional damages for willfulness. The Judge found that the Company’s infringement was willful, and awarded enhanced damages of $5.0 million to WesternGeco (WesternGeco had sought $43.6 million in such damages.) The District Court also ordered the appeal bond to be released and discharged. The Court’s findings and ruling were memorialized in an order issued on May 16, 2017. On June 30, 2017, the Company and WesternGeco agreed that neither of them would appeal the District Court's award of $5.0 million in enhanced damages. Upon assessment of the enhanced damages, the Company accrued $5.0 million in the first quarter of 2017. As the Company have paid the $5.0 million , the accrual has been adjusted, and as of December 31, 2018, the loss contingency accrual was zero . WesternGeco filed a second petition in the Supreme Court on February 17, 2017, appealing the lost profits issue again. On May 30, 2017, the Supreme Court called for the U.S. Solicitor General’s views on whether or not the Supreme Court ought to hear WesternGeco’s appeal. On December 6, 2017, the Solicitor General filed its brief, and took the position that the Supreme Court ought to hear the appeal and that foreign lost profits ought to be available. On January 12, 2018, the Supreme Court agreed to hear the appeal. The specific issue before the Supreme Court was whether lost profits arising from use of prohibited combinations occurring outside of the United States are categorically unavailable in cases where patent infringement is proven under 35 U.S.C. § 271(f)(2) (the statute under which the Company were held to have infringed WesternGeco’s patents, and upon which the District Court and Court of Appeals relied in entering their rulings). The Supreme Court heard oral arguments on April 16, 2018. The Company argued that the Court of Appeals’ decision that eliminated lost profits ought to be affirmed. WesternGeco and the Solicitor General argued that the Court of Appeals’ decision that eliminated lost profits ought to be reversed. On June 22, 2018, the Supreme Court reversed the judgment of the Court of Appeals, held that the award of lost profits to WesternGeco by the District Court was a permissible application of Section 284 of the Patent Act, and remanded the case back to the Court of Appeals for further proceedings consistent with its (the Supreme Court’s) opinion. On July 24, 2018, the Supreme Court issued the judgment that returned the case to the Court of Appeals. On July 27, 2018, the Court of Appeals vacated its September 21, 2016 judgment with respect to damages, and ordered WesternGeco and the Company to submit supplemental briefing on what relief is appropriate in light of the Supreme Court’s decision. The Company and WesternGeco each submitted briefing in accordance with the Court of Appeals’ order (the last brief was filed on September 7, 2018). The Company argued in its brief to the Court of Appeals that lost profits were not available to WesternGeco because the jury instructions required them to find that the Company had been WesternGeco’s direct competitor in the survey markets where WesternGeco had lost profits, and that the jury could not have found so. Additionally, we argued that the award of lost profits and reasonable royalties ought to be vacated and retried on separate grounds due to the outcome of an Inter Partes Review (“IPR”) filed with the Patent Trial and Appeal Board (“PTAB”) of the Patent and Trademark Office. Until the Court of Appeals’ January 11, 2019 decision issued (which is described below), the IPR was an administrative proceeding that was separate from the 2009 lawsuit. By means of the IPR, the Company joined a challenge to the validity of several of WesternGeco’s patent claims that another company had filed. While the 2009 lawsuit was pending on appeal, the PTAB invalidated four of the six patent claims that formed the basis for the lawsuit judgment against the Company. WesternGeco appealed the PTAB’s invalidation of its patents to the Court of Appeals. On May 7, 2018, the Court of Appeals affirmed the PTAB’s invalidation of the patents, and on July 16, 2018, the Court of Appeals denied WesternGeco’s petition for a rehearing. On December 13, 2018, WesternGeco filed a petition with the Supreme Court, arguing that the Court of Appeals ought to have overturned the decision of the PTAB. (As of February 7, 2019, the Supreme Court has not indicated whether it will, or will not, hear WesternGeco’s appeal.) In the same brief to the Court of Appeals in which the Company made its “direct competitor” argument, the Company argued that the Court of Appeals’ affirmation of the PTAB’s decision precluded WesternGeco’s damages claims, and that the Court of Appeals should order a new trial as to the royalty damages already paid by the Company. The Company also argued that if the Court of Appeals did not find its “direct competitor” argument persuasive, the Court should nonetheless vacate the District Court’s award of royalty damages and lost profits damages and order a new trial as to both royalty damages and lost profits. In its briefs to the Court of Appeals, WesternGeco argued that the only remaining issue was whether lost profits were unavailable to WesternGeco due to the Company’s “direct competitor” argument, and argued that the invalidation of four of its six patent claims by the PTAB (which was affirmed by the Court of Appeals) should have no effect on lost profits or on the royalty award already paid by the Company. WesternGeco also argued that lost profits should be available notwithstanding the Company’s “direct competitor” argument. Oral arguments took place on November 16, 2018, and on January 11, 2019, the Court of Appeals issued its ruling. In its ruling, the Court of Appeals refused to disturb the award of reasonable royalties to WesternGeco (which the Company paid in 2016), and rejected the Company’s “direct competitor” argument, but vacated the District Court’s award of lost profits damages and remanded the case back to the District Court to determine whether to hold a new trial as to lost profits. The Court of Appeals also ruled that its affirmance of the PTAB’s decision eliminated four of the five patent claims that could have supported the award of lost profits, leaving only one remaining patent claim that could support an award of lost profits. The Court of Appeals further held that the lost profits award can be reinstated by the District Court if the existing trial record establishes that the jury must have found that the technology covered by the one remaining patent claim was essential for performing the surveys upon which lost profits were based. To make such a finding, the District Court must conclude that the present trial record establishes that there was no dispute that the technology covered by the one remaining patent claim, independent of the technology of the now-invalid claims, was required to perform the surveys. The Court of Appeals ruling further provides that if, but only if, the District Court concludes that WesternGeco established at trial, with undisputed evidence, that the remaining claim covers technology that was necessary to perform the surveys, then the District Court may deny a new trial and reinstate lost profits. Other The Company has been named in various other lawsuits or threatened actions that are incidental to its ordinary business. Litigation is inherently unpredictable. Any claims against the Company, whether meritorious or not, could be time-consuming, cause the Company to incur costs and expenses, require significant amounts of management time and result in the diversion of significant operational resources. The results of these lawsuits and actions cannot be predicted with certainty. Management currently believes that the ultimate resolution of these matters will not have a material adverse impact on the financial condition, results of operations or liquidity of the Company.

Other Income (Expense)

Other Income (Expense)	12 Months Ended
	Dec. 31, 2018
Other Income and Expenses [Abstract]
Other Income (Expense)	Other Income (Expense) A summary of other income (expense) follows (in thousands): Years Ended December 31, 2018 2017 2016 (Accrual for) reduction of loss contingency related to legal proceedings (Footnote 8) $ — $ (5,000 ) $ 1,168 Recovery of INOVA bad debts — 844 3,983 Loss on bond exchange — — (2,182 ) Other income (expense) (436 ) 211 (1,619 ) Total other income (expense), net $ (436 ) $ (3,945 ) $ 1,350

Details of Selected Balance She

Details of Selected Balance Sheet Accounts	12 Months Ended
	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Details of Selected Balance Sheet Accounts	Details of Selected Balance Sheet Accounts Accounts Receivable A summary of accounts receivable follows (in thousands): December 31, 2018 2017 Accounts receivable, principally trade $ 26,558 $ 20,050 Less allowance for doubtful accounts (430 ) (572 ) Accounts receivable, net $ 26,128 $ 19,478 Inventories A summary of inventories follows (in thousands): December 31, 2018 2017 Raw materials and purchased subassemblies $ 20,011 $ 20,448 Work-in-process 1,032 1,146 Finished goods 8,111 7,953 Less reserve for excess and obsolete inventories (15,024 ) (15,039 ) Inventories, net $ 14,130 $ 14,508 Property, Plant, Equipment and Seismic Rental Equipment A summary of property, plant, equipment and seismic rental equipment follows (in thousands): December 31, 2018 2017 Buildings $ 15,707 $ 15,822 Machinery and equipment 132,135 145,654 Seismic rental equipment 1,423 1,677 Furniture and fixtures 3,859 3,869 Other 30,104 28,965 Total 183,228 195,987 Less accumulated depreciation (133,634 ) (143,834 ) Less impairment of long-lived assets (36,553 ) — Property, plant, equipment and seismic rental equipment, net $ 13,041 $ 52,153 Total depreciation expense, including amortization of assets recorded under capital leases, for 2018 , 2017 and 2016 was $7.6 million , $15.2 million and $20.3 million , respectively. Accrued Expenses A summary of accrued expenses follows (in thousands): December 31, 2018 2017 Compensation, including compensation-related taxes and commissions $ 14,502 $ 19,809 Accrued multi-client data library acquisition costs 3,746 5,104 Income tax payable 7,577 1,868 Accrual for loss contingency related to legal proceedings (Footnote 8) — 3,750 Other 5,586 8,166 Total $ 31,411 $ 38,697 Other Long-term Liabilities A summary of other long-term liabilities follows (in thousands): December 31, 2018 2017 Deferred lease liabilities 11,465 12,811 Other 429 1,115 Total $ 11,894 $ 13,926

Goodwill

Goodwill	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	Goodwill On December 31, 2018 , the Company completed the annual reviews of the carrying value of goodwill in its E&P Technology & Services and Optimization Software & Services reporting units and noted no impairments. The qualitative assessment concluded it was more likely than not that the fair values of the Company’s E&P Technology & Services and Optimization Software & Services reporting units exceeded their carrying values. The following is a summary of the changes in the carrying amount of goodwill for the years ended December 31, 2018 and 2017 (in thousands): E&P Technology & Services Optimization Software & Services Total Balance at January 1, 2017 $ 2,943 $ 19,265 $ 22,208 Impact of foreign currency translation adjustments — 1,881 1,881 Balance at December 31, 2017 2,943 21,146 24,089 Impact of foreign currency translation adjustments — (1,174 ) (1,174 ) Balance at December 31, 2018 $ 2,943 $ 19,972 $ 22,915

Stockholder's Equity and Stock-

Stockholder's Equity and Stock-based Compensation	12 Months Ended
	Dec. 31, 2018
Share-based Payment Arrangement [Abstract]
Stockholders' Equity and Stock-based Compensation	Stockholders' Equity and Stock-based Compensation Public Equity Offering On February 21, 2018, the Company completed the public equity offering (the “Offering”) of its 1,820,000 shares of common stock at a public offering price of $27.50 per share, and warrants to purchase an additional 1,820,000 shares of the Company’s common stock pursuant to the Registration Statement on Form S-3 (No. 33-213769) filed with the Securities and Exchange Commission under the Securities Act of 1933 and declared effective on December 2, 2016. The net proceeds from this Offering were $47.0 million , including transaction expenses. A portion of the net proceeds were used to retire the Company’s $28.5 million Third Lien Notes in March 2018. The warrants have an exercise price of $33.60 per share, are immediately exercisable and expire on March 21, 2019. Stock Option Plans The Company has adopted stock option plans for eligible employees, directors and consultants, which provide for the granting of options to purchase shares of common stock. The options under these plans generally vest in equal annual installments over a four -year period and have a term of ten years. These options are typically granted at pre-established quarterly grant dates with an exercise price per share equal to or greater than the current market price and, upon exercise, are issued from the Company’s unissued common shares. Transactions under the stock option plans are summarized as follows: Option Price per Share Outstanding Vested Available for Grant January 1, 2016 $34.20 - $245.85 560,797 384,305 97,003 Increase in shares authorized — — — 1,150,940 Granted 3.10 415,000 — (415,000 ) Vested — — 67,480 — Cancelled/forfeited 3.10 - 245.85 (128,162 ) (103,432 ) 18,895 Restricted stock granted out of option plans — — — (259,300 ) Restricted stock forfeited or cancelled for employee minimum income taxes and returned to the plans — — — 7,182 December 31, 2016 $3.10 - $245.85 847,635 348,353 599,720 Granted 13.15 156,000 — (156,000 ) Vested — — 149,537 — Exercised 3.10 (15,000 ) (15,000 ) — Cancelled/forfeited 3.10 - 245.85 (98,294 ) (47,612 ) 82,118 Restricted stock granted out of option plans — — — (59,500 ) Restricted stock forfeited or cancelled for employee minimum income taxes and returned to the plans — — — 22,065 December 31, 2017 3.10 - 245.85 890,341 435,278 488,403 Increase in shares authorized — — — 1,200,000 Granted 24.50 10,000 — (10,000 ) Vested — — 153,944 — Exercised 3.10 (70,086 ) (70,086 ) — Cancelled/forfeited 3.10 - 245.85 (44,365 ) (44,231 ) 2,568 Restricted stock granted out of option plans — — — (996,775 ) Restricted stock forfeited or cancelled for employee minimum income taxes and returned to the plans — — — 48,524 December 31, 2018 $3.10 - $151.35 785,890 474,905 732,720 Stock options outstanding at December 31, 2018 are summarized as follows: Option Price per Share Outstanding Weighted Average Exercise Price of Outstanding Options Weighted Average Remaining Contract Life Vested Weighted Average Exercise Price of Vested Options $3.10 - $57.90 558,997 $ 15.64 7.2 years 248,012 $ 24.32 $61.05 - $71.85 75,231 $ 62.17 4.7 years 75,231 $ 62.17 $81.60 - $99.60 108,610 $ 88.94 3.6 years 108,610 $ 88.94 $106.05 - $151.35 43,052 $ 108.84 2.3 years 43,052 $ 108.84 Totals 785,890 $ 35.33 5.4 years 474,905 $ 52.76 Additional information related to the Company’s stock options follows: Number of Shares Weighted Average Exercise Price Weighted Average Grant Date Fair Value Weighted Average Remaining Contractual Life Aggregate Intrinsic Value (000’s) Total outstanding at January 1, 2018 890,341 $ 36.17 6.4 years $ 6,774 Options granted 10,000 $ 24.50 $ 15.23 Options exercised (70,086 ) $ 3.10 Options cancelled (134 ) $ 61.05 Options forfeited (44,231 ) $ 100.85 Total outstanding at December 31, 2018 785,890 $ 35.33 5.4 years $ 572 Options exercisable and vested at December 31, 2018 474,905 $ 52.76 5 years $ 213 The total intrinsic value of options exercised during 2018 , 2017 and 2016 was $1.4 million , less than $0.1 million and less than $0.1 million , respectively. Cash received from option exercises under all share-based payment arrangements for 2018 and 2017 was $0.2 million and less than $0.1 million , respectively, and during 2016 , there was no cash received. The weighted average grant date fair value for stock option awards granted during 2018 , 2017 and 2016 was $15.23 , $8.10 and $2.04 per share, respectively. The Company calculated the fair value of each stock option on the date of grant using the Black-Scholes option pricing model. The following assumptions were used for each respective period: Years Ended December 31, 2018 2017 2016 Risk-free interest rates 2.78% 2.14% 1.3% Expected lives (in years) 5.0 5.0 5.5 Expected dividend yield —% —% —% Expected volatility 73.67% 74.41% 78.76% The computation of expected volatility during 2018 , 2017 and 2016 was based on an equally weighted combination of historical volatility and market-based implied volatility. Historical volatility was calculated from historical data for a period of time approximately equal to the expected term of the option award, starting from the date of grant. Market-based implied volatility was derived from traded options on the Company’s common stock having a term of six months. The Company’s computation of expected life in 2018 , 2017 and 2016 was determined based on historical experience of similar awards, giving consideration to the contractual terms of the stock-based awards, vesting schedules and expectations of future employee behavior. The risk-free interest rate assumption is based upon the U.S. Treasury yield curve in effect at the time of grant for periods corresponding with the expected life of the option. Restricted Stock and Restricted Stock Unit Plans On November 30, 2018, the Company’s stockholders approved certain amendments to the Company’s Second Amended and Restated 2013 Long-term Incentive Plan (the “2013 LTIP”) including increasing the total number of shares of common stock available for issuance under the 2013 LTIP by 1.2 million shares, for a total of approximately 1.7 million shares, eliminating the restriction on the number of shares in the 2013 LTIP that can be issued as full value awards and certain other technical updates and clarifications related to Section 162(m) of the internal revenue code, as amended. The Company has issued restricted stock and restricted stock units under the Company’s 2013 LTIP, as amended and other applicable plans. Restricted stock units are awards that obligate the Company to issue a specific number of shares of common stock in the future if continued service vesting requirements are met. Non-forfeitable ownership of the common stock will vest over a period as determined by the Company in its sole discretion, generally in equal annual installments over a three -year period. Shares of restricted stock awarded may not be sold, assigned, transferred, pledged or otherwise encumbered by the grantee during the vesting period. On December 1, 2018, the Company issued 900,002 restricted stocks to selected employees with a grant date fair value $7.19 , $6.51 and $5.89 for each of the tranches. The vesting of these restricted stocks is achieved through both a market condition and a service condition. The market condition is achieved, in part or in full, in the event that during the three -year period beginning on the date of grant the 20 -day trailing volume-weighted average price of a share of common stock reaches or exceeds (i) $17.50 for the first 1/3 of the awards, (ii) $22.50 for the second 1/3 of the awards, and (iii) $27.50 for the final 1/3 of the awards. The service condition restricts the ability of the holders to exercise awards until certain service milestones have been reached such that (i) no more than 1/3 of the awards may be exercised, if vested, on and after the first anniversary of the date of grant, (ii) no more than 2/3 of the awards may be exercised, if vested, on and after the second anniversary of the date of grant and (iii) all of the awards may be exercised, if vested, on and after the third anniversary of the date of grant. The status of the Company’s restricted stock and restricted stock unit awards for 2018 follows: Number of Shares/Units Total nonvested at January 1, 2018 201,702 Granted 996,775 Vested (151,852 ) Forfeited (2,500 ) Total nonvested at December 31, 2018 1,044,125 At December 31, 2018 , 2017 and 2016 , the intrinsic value of restricted stock and restricted stock unit awards was approximately $5.4 million , $4.0 million and $1.7 million , respectively. The weighted average grant date fair value for restricted stock and restricted stock unit awards granted during 2018 , 2017 and 2016 was $10.60 , $11.36 and $3.81 per share, respectively. The total fair value of shares vested during 2018 , 2017 and 2016 was $3.8 million , $0.6 million and $0.2 million , respectively. Stock Appreciation Rights Plan The Company has adopted a stock appreciation rights plan which provides for the award of stock appreciation rights (“SARs”) to directors and selected key employees and consultants. The awards under this plan are subject to the terms and conditions set forth in agreements between the Company and the holders. The exercise price per SAR is not to be less than one hundred percent of the fair market value of a share of common stock on the date of grant of the SAR. The term of each SAR shall not exceed ten years from the grant date. Upon exercise of a SAR, the holder shall receive a cash payment in an amount equal to the spread specified in the SAR agreement for which the SAR is being exercised. In no event will any shares of common stock be issued, transferred or otherwise distributed under the plan. On December 1, 2018, the Company issued 960,009 SARs awards to selected employees with an exercise price of $8.85 (“2018 SARs”). None of these 2018 SARs were awarded to non-employee directors. The 2018 SARs have the same service and market vesting conditions as the restricted stocks issued on December 1, 2018, as described above. The maximum value of each 2018 SARs is capped at $18.65 (the spread between the share price cap of $27.50 and the $8.85 per award price). The 2018 SARs are considered liability awards and as such, these amounts are accrued in the liability section of the consolidated balance sheets. The Company calculated the fair value of each 2018 SARs award as of December 31, 2018 using a Monte Carlo simulation model. The following assumptions were used: Risk-free interest rates 3.0 % Expected lives (in years) 5.31 Expected dividend yield — % Expected volatility 82.9 % On March 1, 2016, the Company issued 1,210,000 SARs awards to 15 selected key employees with an exercise price of $3.10 (“2016 SARs”). None of these 2016 SARs were awarded to non-employee directors. The vesting of these 2016 SARs is achieved through both a market condition and a service condition. The market condition is achieved, in part or in full, in the event that during the four -year period beginning on the date of grant the 20 -day trailing volume-weighted average price of a share of common stock is (i) greater than 120% of the exercise price for the first 1/3 of the awards, (ii) greater than 125% of the exercise price for the second 1/3 of the awards and (iii) greater than 130% of the exercise price for the final 1/3 of the awards. The service condition restricts the ability of the holders to exercise awards until certain service milestones have been reached such that (i) no more than 1/3 of the awards may be exercised, if vested, on and after the first anniversary of the date of grant, (ii) no more than 2/3 of the awards may be exercised, if vested, on and after the second anniversary of the date of grant and (iii) all of the awards may be exercised, if vested, on and after the third anniversary of the date of grant. The maximum value of each 2016 SARs is capped at $19.40 (the spread between the share price cap of $22.50 and the $3.10 per award price). On December 13, 2017, the Compensation Committee (the “Committee”) of the Board of Directors (the “Board”) of the Company authorized and approved the acceleration of the vesting date to December 13, 2017 for the second tranche of the Company’s outstanding 2016 SARs. The second tranche of the 2016 SARs awards was originally scheduled to vest on March 1, 2018. The vesting of the second tranche of the 2016 SARs awards was accelerated to facilitate the exercise by the 2016 SARs participants, if they so choose, of a larger portion of the 2016 SARs awards prior to year-end, as such an exercise would minimize the potential cash flow impact of any such exercise in the first quarter of 2018, would mitigate the ongoing mark to market accounting requirements for cash-settled 2016 SARs, and would afford the 2016 SARs participants liquidity to invest in common stock of the Company to further align their interests with those of the Company’s stockholders. Participants exercised 663,330 SARs awards at a $9.95 gain per share. The 2016 SARs are considered liability awards and as such, these amounts are accrued in the liability section of the consolidated balance sheets. The Company calculated the fair value of each 2016 SARs award on the date of grant and remeasured at each reporting period using a Monte Carlo simulation model. However, as of December 31, 2018, the fair value of the 2016 SARs awards were derived using the intrinsic value method since the final tranche of the 2016 SARs awards vest on March 1, 2019, less than twelve months from the balance sheet date. On March 1, 2015, the Company issued 207,207 SARs awards to 16 selected key employees with an exercise price of $34.20 (“2015 SARs”). None of these 2015 SARs were awarded to non-employee directors. The 2015 SARs awards number and exercise price have been retroactively adjusted to reflect the one-for-fifteen reverse stock split completed on February 4, 2016. The vesting of these 2015 SARs is achieved through both a market condition and a service condition. The market condition is achieved, in part or in full, in the event that during the four -year period beginning on the date of grant the 20 -day trailing volume-weighted average price of a share of common stock is (i) greater than 120% of the exercise price for the first 1/3 of the awards, (ii) greater than 125% of the exercise price for the second 1/3 of the awards and (iii) greater than 130% of the exercise price for the final 1/3 of the awards. The exercise condition restricts the ability of the holders to exercise awards until certain service milestones have been reached such that (i) no more than 1/3 of the awards may be exercised, if vested, on and after the first anniversary of the date of grant, (ii) no more than 2/3 of the awards may be exercised, if vested, on and after the second anniversary of the date of grant and (iii) all of the awards may be exercised, if vested, on and after the third anniversary of the date of grant. The 2015 SARs are considered liability awards and as such, these amounts are accrued in the liability section of the consolidated balance sheets. The Company calculated the fair value of each 2015 SARs award on the date of grant and remeasured at each reporting period using a Monte Carlo simulation model. As of December 31, 2018, the market condition had not been met for the 2015 SARs. If the market condition is not met by March 1, 2019, the 2015 SARs award will expire. The Company recorded $0.8 million of share-based compensation expense during 2018 , $6.6 million during 2017 and $0.5 million in 2016 , related to employee SARs. Additional information related to the Company's SARs follows: Number of Shares Weighted Average Exercise Price Weighted Average Grant Date Fair Value Weighted Average Remaining Contractual Life Aggregate Intrinsic Value (000’s) Total outstanding at January 1, 2016 216,532 $ 34.67 SARs granted 1,210,000 $ 3.10 $ 17.55 SARs cancelled (10,399 ) $ 34.20 Total outstanding at December 31, 2016 1,416,133 $ 7.70 SARs exercised (713,330 ) $ 3.10 SARs cancelled (136,939 ) $ 7.70 Total outstanding at December 31, 2017 565,864 $ 13.49 SARs granted 960,009 $ 8.85 8.85 SARs exercised (34,999 ) $ 3.10 SARs forfeited (9,333 ) $ 45.00 Total outstanding at December 31, 2018 1,481,541 $ 10.53 8.1 years $ 718 SARs exercisable and vested at December 31, 2018 — $ — Stock-based Compensation Expense The following tables summarizes stock-based compensation expense for the years ended December 31, 2018 , 2017 and 2016 as follows (in thousands): Years Ended December 31, 2018 2017 2016 Stock-based compensation expense $ 3,337 $ 2,552 $ 3,267 Tax benefit related thereto (698 ) (862 ) (1,168 ) Stock-based compensation expense, net of tax $ 2,639 $ 1,690 $ 2,099 Years Ended December 31, 2018 2017 2016 Stock appreciation rights expense $ 822 $ 6,611 547 Tax benefit related thereto (173 ) (2,314 ) (191 ) Stock appreciation rights expense, net of tax $ 649 $ 4,297 $ 356 Equity Investment Program To encourage the Company’s executive officers and other key employees to purchase common stock of the Company and further align their interests with those of the Company’s stockholders, the Board authorized and approved an equity investment program (the “Program”) pursuant to which certain of the executive officers and other key employees of the Company are permitted, but not obligated, to purchase unregistered shares of common stock of the Company directly from the Company at market prices. In connection with any such purchases, the Committee authorized and approved, on December 13, 2017, a grant by the Company to such purchasing executive officers and key employees of a certain number of shares of restricted stock. On December 13, 2017, the Committee also authorized and approved to grant to certain executive officers and key employees a certain number of shares of restricted stock in connection with certain purchases of shares of the Company’s common stock in the open market. Specifically, for each five (5) shares directly purchased from the Company or in the open market during a defined period (to expire no later than December 31, 2017), the Company will issue one (1) share of restricted stock, subject to certain limitations as to the total number of restricted shares to be issued by the Company. Provided that an executive officer or key employee remains employed with the Company until March 1, 2018, the restricted stock will be granted as of March 1, 2018, will vest in full on the date that is 90 days after the grant date and will be subject to the other terms and conditions of the Company’s form of restricted stock agreement and the Company’s 2013 LTIP. The Company sold, in a private placement under Section 4(a)(2) of the Securities Act of 1933, as amended on December 14, 2017, 120,567 shares of Company common stock at $13.05 per share (the closing price of the Company’s common stock on the NYSE on such date) and executive officers and other key employees purchased 219,346 shares in the open market. On May 30, 2018, 43,865 shares of restricted stock vested at $24.75 per share.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information and Non-Cash Activity	12 Months Ended
	Dec. 31, 2018
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information and Non-Cash Activity	Supplemental Cash Flow Information and Non-Cash Activity Supplemental disclosure of cash flow information follows (in thousands): Years Ended December 31, 2018 2017 2016 Cash paid during the period for: Interest $ 5,731 $ 14,181 $ 15,691 Income taxes 3,260 7,030 4,474 Non-cash items from investing and financing activities: Purchase of computer equipment financed through capital leases 3,297 — — Leasehold improvement paid by landlord — — 955 Issuance of stock in bond exchange — — 10,741 Transfer of inventory to property, plant and equipment — — 17,662 (a) Investment in multi-client data library financed through trade payables 4,956 9,059 — (a) This transfer of $17.7 million of inventory to property, plant, equipment and seismic rental equipment in December 2016, relates to ocean bottom seismic equipment manufactured by the Company to be deployed in the acquisition of ocean bottom seismic data.

Operating Leases

Operating Leases	12 Months Ended
	Dec. 31, 2018
Leases, Operating [Abstract]
Operating Leases	Operating Leases Lessee. The Company leases certain equipment, offices and warehouse space under non-cancelable operating leases. Rental expense was $10.1 million , $11.4 million and $11.3 million for 2018 , 2017 and 2016 , respectively. A summary of future rental commitments over the next five years under non-cancelable operating leases follows (in thousands): Years Ending December 31, 2019 $ 13,248 2020 12,857 2021 11,075 2022 10,821 2023 9,205 Total $ 57,206

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments Authoritative guidance on fair value measurements defines fair value, establishes a framework for measuring fair value and stipulates the related disclosure requirements. The Company follows a three-level hierarchy, prioritizing and defining the types of inputs used to measure fair value. Due to their highly liquid nature, the amount of the Company’s other financial instruments, including cash and cash equivalents, restricted cash, accounts and unbilled receivables, short term investments, accounts payable and accrued multi-client data library royalties, represent their approximate fair value. The carrying amounts of the Company’s long-term debt as of December 31, 2018 and 2017 were $124.7 million and $160.7 million , respectively, compared to its fair values of $120.7 million and $158.2 million as of December 31, 2018 and 2017 , respectively. The fair value of the long-term debt was calculated using Level 1 inputs, including an active market price. Fair value measurements are applied with respect to non-financial assets and liabilities measured on a non-recurring basis, which would consist of measurements primarily of goodwill, intangibles assets, multi-client data library and property, plant and equipment and seismic rental equipment.

Benefit Plans

Benefit Plans	12 Months Ended
	Dec. 31, 2018
Retirement Benefits [Abstract]
Benefit Plans	Benefit Plans The Company has a 401(k) retirement savings plan, which covers substantially all employees. Employees may voluntarily contribute up to 60% of their compensation , as defined, to the plan. The Company matched the employee contribution at a rate of 50% of the first 6% of compensation contributed to the plan. Company contributions to the plans were $0.9 million , $0.8 million and $0.8 million , during 2018 , 2017 and 2016 , respectively.

Selected Quarterly Information

Selected Quarterly Information (Unaudited)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Information (Unaudited)	Selected Quarterly Information — (Unaudited) A summary of selected quarterly information follows (in thousands, except per share amounts): Three Months Ended March 31, 2018 June 30, 2018 September 30, 2018 December 31, 2018 Service revenues $ 25,086 $ 15,752 $ 37,105 $ 61,095 Product revenues 8,422 8,991 10,095 13,499 Total net revenues 33,508 24,743 47,200 74,594 Gross profit (loss) 6,853 (1,517 ) 16,475 37,809 Loss from operations (12,640 ) (22,519 ) (2,452 ) (16,661 ) Interest expense, net (3,836 ) (2,911 ) (3,022 ) (3,203 ) Other income (expense), net (791 ) 84 91 180 Income tax expense (benefit) 1,072 154 2,079 (587 ) Net income attributable to noncontrolling interests (87 ) (366 ) (74 ) (246 ) Net loss applicable to ION $ (18,426 ) $ (25,866 ) $ (7,536 ) $ (19,343 ) Net loss per share: Basic $ (1.44 ) $ (1.86 ) $ (0.54 ) $ (1.38 ) Diluted $ (1.44 ) $ (1.86 ) $ (0.54 ) $ (1.38 ) Three Months Ended March 31, 2017 June 30, 2017 September 30, 2017 December 31, 2017 Service revenues $ 23,828 $ 34,454 $ 52,615 $ 48,513 Product revenues 8,728 11,547 8,480 9,389 Total net revenues 32,556 46,001 61,095 57,902 Gross profit 6,101 15,618 30,109 23,811 Income (loss) from operations (13,912 ) (3,572 ) 9,936 (1,151 ) Interest expense, net (4,464 ) (4,241 ) (3,959 ) (4,045 ) Other income (expense), net (5,068 ) 192 722 209 Income tax expense (benefit) (418 ) 2,402 1,686 (3,646 ) Net income attributable to noncontrolling interests (316 ) (418 ) (78 ) (53 ) Net income (loss) applicable to ION $ (23,342 ) $ (10,441 ) $ 4,935 $ (1,394 ) Net income (loss) per share: Basic $ (1.98 ) $ (0.88 ) $ 0.42 $ (0.12 ) Diluted $ (1.98 ) $ (0.88 ) $ 0.41 $ (0.12 ) The sum of the quarterly per share information may not tie to per share information in the Consolidated Statements of Operations due to rounding.

Certain Relationships and Relat

Certain Relationships and Related Party Transactions	12 Months Ended
	Dec. 31, 2018
Related Party Transactions [Abstract]
Certain Relationships and Related Party Transactions	Certain Relationships and Related Party Transactions For 2018 , 2017 and 2016 , the Company recorded revenues from BGP of $4.9 million , $4.4 million and $3.6 million , respectively. Receivables due from BGP were $1.6 million and $0.6 million at December 31, 2018 and 2017 , respectively. BGP owned approximately 10.6% of the Company’s outstanding common stock as of December 31, 2018 . Mr. James M. Lapeyre, Jr. is the Chairman of the Board on ION’s board of directors and a significant equity owner of Laitram, L.L.C. (Laitram), and he has served as president of Laitram and its predecessors since 1989. Laitram is a privately-owned, New Orleans-based manufacturer of food processing equipment and modular conveyor belts. Mr. Lapeyre and Laitram together owned approximately 8.8% of the Company’s outstanding common stock as of December 31, 2018 . The Company acquired DigiCourse, Inc., the Company’s marine positioning products business, from Laitram in 1998. In connection with that acquisition, the Company entered into a Continued Services Agreement with Laitram under which Laitram agreed to provide the Company certain bookkeeping, software, manufacturing and maintenance services. Manufacturing services consist primarily of machining of parts for the Company’s marine positioning systems. The term of this agreement expired in September 2001 but the Company continues to operate under its terms. In addition, from time to time, when the Company has requested, the legal staff of Laitram has advised the Company on certain intellectual property matters with regard to the Company’s marine positioning systems. During 2018 and 2017, the Company paid Laitram and its affiliates $0.4 million and $0.2 million , respectively, which consisted of manufacturing services and reimbursement of costs. During 2016, the Company paid less than $0.1 million for reimbursement for costs related to providing administrative and other back-office support services in connection with the Company’s Louisiana marine operations. In addition, the Company is currently subleasing approximately 4,100 square feet of office space to Laitram. In the opinion of the Company’s management, the terms of these services are fair and reasonable and as favorable to the Company as those that could have been obtained from unrelated third parties at the time of their performance.

Condensed Consolidating Financi

Condensed Consolidating Financial Information	12 Months Ended
	Dec. 31, 2018
Condensed Financial Information Disclosure [Abstract]
Condensed Consolidating Financial Information	Condensed Consolidating Financial Information The Second Lien Notes were issued by ION Geophysical Corporation, and are guaranteed by the Company’s current material U.S. subsidiaries: GX Technology Corporation, ION Exploration Products (U.S.A.), Inc. and I/O Marine Systems, Inc. (“the Guarantors”), all of which are wholly-owned subsidiaries. The Guarantors have fully and unconditionally guaranteed the payment obligations of ION Geophysical Corporation with respect to these debt securities. In August 2018, as part of the Company entering into the Third Amendment to its Credit Agreement, the Company joined the Mexican Subsidiary as a guarantor with respect to the Second Lien Notes. All periods period presented below have been updated to include the Mexican Subsidiary within The Guarantors column. The following condensed consolidating financial information presents the results of operations, financial position and cash flows for: • ION Geophysical Corporation and the Guarantors (in each case, reflecting investments in subsidiaries utilizing the equity method of accounting). • All other subsidiaries of ION Geophysical Corporation that are non-guarantors. • The consolid ating adjustments necessary to present ION Geophysical Corporation’s results on a consolidated basis. This condensed consolidating financial information should be read in conjunction with the accompanying consolidated financial statements and footnotes. For additional information pertaining to the Notes, see Item 7. “ Management’s Discussion and Analysis of Financial Condition and Results of Operations” in Part 2 of this Form 10-K. December 31, 2018 Balance Sheet ION Geophysical Corporation The Guarantors All Other Subsidiaries Consolidating Adjustments Total Consolidated (In thousands) ASSETS Current assets: Cash and cash equivalents $ 13,782 $ 47 $ 19,722 $ — $ 33,551 Accounts receivable, net 8 17,349 8,771 — 26,128 Unbilled receivables — 12,697 31,335 — 44,032 Inventories — 8,721 5,409 — 14,130 Prepaid expenses and other current assets 3,891 1,325 2,566 — 7,782 Total current assets 17,681 40,139 67,803 — 125,623 Deferred income tax asset 805 6,261 125 — 7,191 Property, plant, equipment and seismic rental equipment, net 489 8,922 3,630 — 13,041 Multi-client data library, net — 70,380 3,164 — 73,544 Investment in subsidiaries 836,002 247,359 — (1,083,361 ) — Goodwill — — 22,915 — 22,915 Intercompany receivables — 305,623 66,021 (371,644 ) — Other assets 1,723 643 69 — 2,435 Total assets $ 856,700 $ 679,327 $ 163,727 $ (1,455,005 ) $ 244,749 LIABILITIES AND EQUITY Current liabilities: Current maturities of long-term debt $ 1,159 $ 1,069 $ — $ — $ 2,228 Accounts payable 2,407 29,602 2,904 — 34,913 Accrued expenses 7,011 10,036 14,364 — 31,411 Accrued multi-client data library royalties — 29,040 216 — 29,256 Deferred revenue — 6,515 1,195 — 7,710 Total current liabilities 10,577 76,262 18,679 — 105,518 Long-term debt, net of current maturities 117,644 1,869 — — 119,513 Intercompany payables 721,817 — — (721,817 ) — Other long-term liabilities 430 5,698 5,766 — 11,894 Total liabilities 850,468 83,829 24,445 (721,817 ) 236,925 Equity: Common stock 140 290,460 47,776 (338,236 ) 140 Additional paid-in capital 952,626 180,700 203,908 (384,608 ) 952,626 Accumulated earnings (deficit) (926,092 ) 390,691 (12,475 ) (378,216 ) (926,092 ) Accumulated other comprehensive income (loss) (20,442 ) 4,324 (22,023 ) 17,699 (20,442 ) Due from ION Geophysical Corporation — (270,677 ) (79,496 ) 350,173 — Total stockholders’ equity 6,232 595,498 137,690 (733,188 ) 6,232 Noncontrolling interests — — 1,592 — 1,592 Total equity 6,232 595,498 139,282 (733,188 ) 7,824 Total liabilities and equity $ 856,700 $ 679,327 $ 163,727 $ (1,455,005 ) $ 244,749 December 31, 2017 Balance Sheet ION Geophysical Corporation The Guarantors All Other Subsidiaries Consolidating Adjustments Total Consolidated (In thousands) ASSETS Current assets: Cash and cash equivalents $ 39,344 $ 66 $ 12,646 $ — $ 52,056 Accounts receivable, net 50 12,496 6,932 — 19,478 Unbilled receivables — 34,484 2,820 — 37,304 Inventories — 8,686 5,822 — 14,508 Prepaid expenses and other current assets 2,427 4,530 686 — 7,643 Total current assets 41,821 60,262 28,906 — 130,989 Deferred income tax asset 1,264 336 153 — 1,753 Property, plant, equipment and seismic rental equipment, net 511 7,170 44,472 — 52,153 Multi-client data library, net — 81,442 7,858 — 89,300 Investment in subsidiaries 693,679 321,934 — (1,015,613 ) — Goodwill — — 24,089 — 24,089 Intercompany receivables — 162,017 60,394 (222,411 ) — Other assets 686 1,811 288 — 2,785 Total assets $ 737,961 $ 634,972 $ 166,160 $ (1,238,024 ) $ 301,069 LIABILITIES AND EQUITY Current liabilities: Current maturities of long-term debt $ 39,774 $ 250 $ — $ — $ 40,024 Accounts payable 1,774 20,982 2,195 — 24,951 Accrued expenses 12,284 16,957 9,456 — 38,697 Accrued multi-client data library royalties — 26,824 211 — 27,035 Deferred revenue — 7,231 1,679 — 8,910 Total current liabilities 53,832 72,244 13,541 — 139,617 Long-term debt, net of current maturities 116,691 29 — — 116,720 Intercompany payables 537,417 — — (537,417 ) — Other long-term liabilities 454 6,084 7,388 — 13,926 Total liabilities 708,394 78,357 20,929 (537,417 ) 270,263 Equity: Common stock 120 290,460 49,394 (339,854 ) 120 Additional paid-in capital 903,247 180,701 202,290 (382,991 ) 903,247 Accumulated earnings (deficit) (854,921 ) 317,324 (9,247 ) (308,077 ) (854,921 ) Accumulated other comprehensive income (loss) (18,879 ) 4,372 (19,681 ) 15,309 (18,879 ) Due from ION Geophysical Corporation — (236,242 ) (78,764 ) 315,006 — Total stockholders’ equity 29,567 556,615 143,992 (700,607 ) 29,567 Noncontrolling interests — — 1,239 — 1,239 Total equity 29,567 556,615 145,231 (700,607 ) 30,806 Total liabilities and equity $ 737,961 $ 634,972 $ 166,160 $ (1,238,024 ) $ 301,069 Year Ended December 31, 2018 Income Statement ION Geophysical Corporation The Guarantors All Other Subsidiaries Consolidating Adjustments Total Consolidated (In thousands) Total net revenues $ — $ 96,649 $ 83,396 $ — $ 180,045 Cost of goods sold — 85,186 35,239 — 120,425 Gross profit — 11,463 48,157 — 59,620 Total operating expenses 32,888 29,235 51,769 — 113,892 Loss from operations (32,888 ) (17,772 ) (3,612 ) — (54,272 ) Interest expense, net (13,010 ) (136 ) 174 — (12,972 ) Intercompany interest, net 1,124 (12,137 ) 11,013 — — Equity in earnings (losses) of investments (26,446 ) 37,219 — (10,773 ) — Other income (expense) (196 ) 116 (356 ) — (436 ) Income (loss) before income taxes (71,416 ) 7,290 7,219 (10,773 ) (67,680 ) Income tax expense (benefit) (245 ) (6,711 ) 9,674 — 2,718 Net income (loss) (71,171 ) 14,001 (2,455 ) (10,773 ) (70,398 ) Net income attributable to noncontrolling interests — — (773 ) — (773 ) Net income (loss) attributable to ION $ (71,171 ) $ 14,001 $ (3,228 ) $ (10,773 ) $ (71,171 ) Comprehensive net income (loss) $ (72,734 ) $ 13,953 $ (4,797 ) $ (8,383 ) $ (71,961 ) Comprehensive income attributable to noncontrolling interest — — (773 ) — (773 ) Comprehensive net income (loss) attributable to ION $ (72,734 ) $ 13,953 $ (5,570 ) $ (8,383 ) $ (72,734 ) Year Ended December 31, 2017 Income Statement ION Geophysical Corporation The Guarantors All Other Subsidiaries Consolidating Adjustments Total Consolidated (In thousands) Total net revenues $ — $ 148,590 $ 48,964 $ — $ 197,554 Cost of goods sold — 90,754 31,161 — 121,915 Gross profit — 57,836 17,803 — 75,639 Total operating expenses 39,000 28,020 17,318 — 84,338 Income (loss) from operations (39,000 ) 29,816 485 — (8,699 ) Interest expense, net (16,729 ) (107 ) 127 — (16,709 ) Intercompany interest, net 1,084 (6,613 ) 5,529 — — Equity in earnings (losses) of investments 27,696 67,290 — (94,986 ) — Other income (expense) (4,610 ) (407 ) 1,072 — (3,945 ) Income (loss) before income taxes (31,559 ) 89,979 7,213 (94,986 ) (29,353 ) Income tax expense (benefit) (1,317 ) (1,427 ) 2,768 — 24 Net income (loss) (30,242 ) 91,406 4,445 (94,986 ) (29,377 ) Net income attributable to noncontrolling interests — — (865 ) — (865 ) Net income (loss) attributable to ION $ (30,242 ) $ 91,406 $ 3,580 $ (94,986 ) $ (30,242 ) Comprehensive net income (loss) $ (27,373 ) $ 91,358 $ 6,550 $ (97,043 ) $ (26,508 ) Comprehensive income attributable to noncontrolling interest — — (865 ) — (865 ) Comprehensive net income (loss) attributable to ION $ (27,373 ) $ 91,358 $ 5,685 $ (97,043 ) $ (27,373 ) Year Ended December 31, 2016 Income Statement ION Geophysical Corporation The Guarantors All Other Subsidiaries Consolidating Adjustments Total Consolidated (In thousands) Total net revenues $ — $ 91,465 $ 81,343 $ — $ 172,808 Cost of goods sold — 87,660 49,116 — 136,776 Gross profit — 3,805 32,227 — 36,032 Total operating expenses 31,438 27,279 20,486 — 79,203 Income (loss) from operations (31,438 ) (23,474 ) 11,741 — (43,171 ) Interest expense, net (18,406 ) (173 ) 94 — (18,485 ) Intercompany interest, net 978 (4,397 ) 3,419 — — Equity in earnings (losses) of investments (19,756 ) 23,368 — (3,612 ) — Other income (expense) 3,528 723 (2,901 ) — 1,350 Income (loss) before income taxes (65,094 ) (3,953 ) 12,353 (3,612 ) (60,306 ) Income tax expense 54 1,337 3,030 — 4,421 Net income (loss) (65,148 ) (5,290 ) 9,323 (3,612 ) (64,727 ) Net income attributable to noncontrolling interests — — (421 ) — (421 ) Net income (loss) attributable to ION $ (65,148 ) $ (5,290 ) $ 8,902 $ (3,612 ) $ (65,148 ) Comprehensive net income (loss) $ (72,331 ) $ (5,290 ) $ 1,719 $ 4,208 $ (71,694 ) Comprehensive income attributable to noncontrolling interest — — (421 ) — (421 ) Comprehensive net income (loss) attributable to ION $ (72,331 ) $ (5,290 ) $ 1,298 $ 4,208 $ (72,115 ) Year Ended December 31, 2018 Statement of Cash Flows ION Geophysical Corporation The Guarantors All Other Subsidiaries Total Consolidated (In thousands) Cash flows from operating activities: Net cash provided by (used in) operating activities $ (37,659 ) $ 39,407 $ 5,350 $ 7,098 Cash flows from investing activities: Investment in multi-client data library — (25,307 ) (2,969 ) (28,276 ) Purchase of property, plant, equipment and seismic rental equipment (392 ) (959 ) (163 ) (1,514 ) Net cash used in investing activities (392 ) (26,266 ) (3,132 ) (29,790 ) Cash flows from financing activities: Repayments under revolving line of credit (10,000 ) — — (10,000 ) Payments on notes payable and long-term debt (30,169 ) (638 ) — (30,807 ) Cost associated with issuance of debt (1,247 ) — — (1,247 ) Intercompany lending 7,983 (12,522 ) 4,539 — Proceeds from employee stock purchases and exercise of stock options 214 — — 214 Net proceeds from issuance of stocks 46,999 — — 46,999 Dividend payment to noncontrolling interest (200 ) — — (200 ) Other financing activities (1,151 ) — — (1,151 ) Net cash provided by (used in) financing activities 12,429 (13,160 ) 4,539 3,808 Effect of change in foreign currency exchange rates on cash, cash equivalents and restricted cash — — 319 319 Net increase (decrease) in cash and cash equivalents (25,622 ) (19 ) 7,076 (18,565 ) Cash, cash equivalents and restricted cash at beginning of period 39,707 66 12,646 52,419 Cash, cash equivalents and restricted cash at end of period $ 14,085 $ 47 $ 19,722 $ 33,854 . The following table is a reconciliation of cash, cash equivalents and restricted cash: December 31, 2018 ION Geophysical Corporation The Guarantors All Other Subsidiaries Total Consolidated (In thousands) Cash and cash equivalents $ 13,782 $ 47 $ 19,722 $ 33,551 Restricted cash included in other long-term assets 303 — — 303 Total cash, cash equivalents, and restricted cash shown in statements of cash flows $ 14,085 $ 47 $ 19,722 $ 33,854 Year Ended December 31, 2017 Statement of Cash Flows ION Geophysical Corporation The Guarantors All Other Subsidiaries Total Consolidated (In thousands) Cash flows from operating activities: Net cash provided by (used in) operating activities $ (22,315 ) $ 73,154 $ (23,227 ) $ 27,612 Cash flows from investing activities: Investment in multi-client data library — (23,710 ) — (23,710 ) Purchase of property, plant, equipment and seismic rental equipment (165 ) (817 ) (81 ) (1,063 ) Net cash used in investing activities (165 ) (24,527 ) (81 ) (24,773 ) Cash flows from financing activities: Payments on notes payable and long-term debt (1,591 ) (3,167 ) (58 ) (4,816 ) Cost associated with issuance of debt (53 ) — — (53 ) Intercompany lending 38,732 (45,609 ) 6,877 — Proceeds from employee stock purchases and exercise of stock options 1,619 — — 1,619 Payments to repurchase bonds — — — — Dividend payment to noncontrolling interest (100 ) — — (100 ) Other financing activities (243 ) — — (243 ) Net cash provided by (used in) financing activities 38,364 (48,776 ) 6,819 (3,593 ) Effect of change in foreign currency exchange rates on cash, cash equivalents and restricted cash — — (260 ) (260 ) Net increase (decrease) in cash and cash equivalents 15,884 (149 ) (16,749 ) (1,014 ) Cash, cash equivalents and restricted cash at beginning of period 23,823 215 29,395 53,433 Cash, cash equivalents and restricted cash at end of period $ 39,707 $ 66 $ 12,646 $ 52,419 The following table is a reconciliation of cash, cash equivalents and restricted cash: December 31, 2017 ION Geophysical Corporation The Guarantors All Other Subsidiaries Total Consolidated (In thousands) Cash and cash equivalents $ 39,344 $ 66 $ 12,646 $ 52,056 Restricted cash included in prepaid expenses and other current assets 60 — — 60 Restricted cash included in other long-term assets 303 — — 303 Total cash, cash equivalents, and restricted cash shown in statements of cash flows $ 39,707 $ 66 $ 12,646 $ 52,419 Year Ended December 31, 2016 Statement of Cash Flows ION Geophysical Corporation The Guarantors All Other Subsidiaries Total Consolidated (In thousands) Cash flows from operating activities: Net cash provided by (used in) operating activities $ (30,732 ) $ 53,107 $ (21,382 ) $ 993 Cash flows from investing activities: Investment in multi-client data library — (14,884 ) — (14,884 ) Purchase of property, plant and equipment (73 ) (313 ) (1,072 ) (1,458 ) Proceeds from sale of a cost-method investment 2,698 — — 2,698 Net cash provided by (used in) investing activities 2,625 (15,197 ) (1,072 ) (13,644 ) Cash flows from financing activities: Payments under revolving line of credit (5,000 ) — — (5,000 ) Borrowings under revolving line of credit 15,000 — — 15,000 Payments on notes payable and long-term debt (17,070 ) (6,316 ) (248 ) (23,634 ) Cost associated with issuance of debt (6,744 ) — — (6,744 ) Repurchase of common stock (964 ) — — (964 ) Intercompany lending 31,867 (34,771 ) 2,904 — Other financing activities (252 ) — — (252 ) Net cash provided by (used in) financing activities 16,837 (41,087 ) 2,656 (21,594 ) Effect of change in foreign currency exchange rates on cash, cash equivalents and restricted cash — — 1,386 1,386 Net decrease in cash and cash equivalents (11,270 ) (3,177 ) (18,412 ) (32,859 ) Cash, cash equivalents and restricted cash at beginning of period 35,093 3,392 47,807 86,292 Cash, cash equivalents and restricted cash at end of period $ 23,823 $ 215 $ 29,395 $ 53,433 The following table is a reconciliation of cash, cash equivalents and restricted cash: December 31, 2016 ION Geophysical Corporation The Guarantors All Other Subsidiaries Total Consolidated (In thousands) Cash and cash equivalents $ 23,042 $ 215 $ 29,395 $ 52,652 Restricted cash included in prepaid expenses and other current assets 260 — — 260 Restricted cash included in other long-term assets 521 — — 521 Total cash, cash equivalents, and restricted cash shown in statements of cash flows $ 23,823 $ 215 $ 29,395 $ 53,433

VALUATION AND QUALIFYING ACCOUN

VALUATION AND QUALIFYING ACCOUNTS	12 Months Ended
	Dec. 31, 2018
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
VALUATION AND QUALIFYING ACCOUNTS	SCHEDULE II ION GEOPHYSICAL CORPORATION AND SUBSIDIARIES VALUATION AND QUALIFYING ACCOUNTS Year Ended December 31, 2016 Balance at Charged (Credited) to Deductions Balance at (In thousands) Allowances for doubtful accounts $ 4,919 $ 1,834 $ (5,310 ) $ 1,443 Allowances for doubtful notes receivable 4,000 — — 4,000 Valuation allowance on deferred tax assets 194,255 23,334 — 217,589 Excess and obsolete inventory 24,475 429 (9,855 ) 15,049 Year Ended December 31, 2017 Balance at Charged (Credited) to Deductions Balance at (In thousands) Allowances for doubtful accounts $ 1,443 $ 949 $ (1,820 ) $ 572 Allowances for doubtful notes receivable 4,000 — — 4,000 Valuation allowance on deferred tax assets 217,589 (64,126 ) — 153,463 Excess and obsolete inventory 15,049 398 (408 ) 15,039 Year Ended December 31, 2018 Balance at Beginning of Year Charged (Credited) to Costs and Expenses Deductions Balance at End of Year (In thousands) Allowances for doubtful accounts $ 572 $ 222 $ (364 ) $ 430 Allowances for doubtful notes receivable 4,000 — — 4,000 Valuation allowance on deferred tax assets 153,463 7,042 — 160,505 Excess and obsolete inventory 15,039 665 (680 ) 15,024

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
General Description and Principles of Consolidation	General Description and Principles of Consolidation ION Geophysical Corporation and its subsidiaries offer a full suite of services and products for seismic data acquisition and processing. The consolidated financial statements include the accounts of ION Geophysical Corporation and its majority-owned subsidiaries (collectively referred to as the “Company” or “ION”). Intercompany balances and transactions have been eliminated. Certain reclassifications were made to previously reported amounts in the consolidated financial statements and notes thereto to make them consistent with the current period presentation.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates are made at discrete points in time based on relevant market information. These estimates may be subjective in nature and involve uncertainties and matters of judgment and, therefore, cannot be determined with precision. Areas involving significant estimates include, but are not limited to, accounts and unbilled receivables, inventory valuation, sales forecasts related to multi-client data libraries, goodwill and intangible asset valuation and deferred taxes. Actual results could materially differ from those estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. The Company places its temporary cash investments with high credit quality financial institutions. At times such investments may be in excess of the Federal Deposit Insurance Corporation insurance limit.
Accounts and Unbilled Receivables	Accounts and Unbilled Receivables Accounts and unbilled receivables are recorded at cost, less the related allowance for doubtful accounts. The Company considers current information and events regarding the customers’ ability to repay their obligations, such as the length of time the receivable balance is outstanding, the customers’ credit worthiness and historical experience. Unbilled receivables relate to revenues recognized on multi-client surveys, imaging services and devices equipment repairs on a proportionate basis, and on licensing of multi-client data libraries for which invoices have not yet been presented to the customer.
Accounts and Unbilled Receivables	Accounts and Unbilled Receivables Accounts and unbilled receivables are recorded at cost, less the related allowance for doubtful accounts. The Company considers current information and events regarding the customers’ ability to repay their obligations, such as the length of time the receivable balance is outstanding, the customers’ credit worthiness and historical experience. Unbilled receivables relate to revenues recognized on multi-client surveys, imaging services and devices equipment repairs on a proportionate basis, and on licensing of multi-client data libraries for which invoices have not yet been presented to the customer.
Inventories	Inventories Inventories are stated at the lower of cost (primarily first-in, first-out method) or net realizable value. The Company provides reserves for estimated obsolescence or excess inventory equal to the difference between cost of inventory and its estimated net realizable value based upon assumptions about future demand for the Company’s products, market conditions and the risk of obsolescence driven by new product introductions.
Property, Plant, Equipment and Seismic Rental Equipment	Property, Plant, Equipment and Seismic Rental Equipment Property, plant, equipment and seismic rental equipment are stated at cost. Depreciation expense is provided straight-line over the following estimated useful lives: Years Machinery and equipment 3-7 Buildings 5-25 Seismic rental equipment 3-5 Leased equipment and other 3-10 Expenditures for renewals and betterments are capitalized; repairs and maintenance are charged to expense as incurred. The cost and accumulated depreciation of assets sold or otherwise disposed of are removed from the accounts and any gain or loss is reflected in operating expenses. The Company evaluates the recoverability of long-lived assets, including property, plant, equipment and seismic rental equipment, when indicators of impairment exist, relying on a number of factors including operating results, business plans, economic projections and anticipated future cash flows. Impairment in the carrying value of an asset held for use is recognized whenever anticipated future undiscounted cash flows from an asset are estimated to be less than its carrying value. The amount of the impairment recognized is the difference between the carrying value of the asset and its fair value. For 2018, the Company identified an indicator of impairment as it relates to its cable-based ocean bottom acquisition technologies.
Multi-Client Data Library	Multi-Client Data Library The multi-client data library consists of seismic surveys that are offered for licensing to customers on a non-exclusive basis. The capitalized costs include costs paid to third parties for the acquisition of data and related activities associated with the data creation activity and direct internal processing costs, such as salaries, benefits, computer-related expenses and other costs incurred for seismic data project design and management. The Company’s method of amortizing the costs of an in-process multi-client data library (the period during which the seismic data is being acquired and/or processed, referred to as the “New Venture” phase) consists of determining the percentage of actual revenue recognized to the total estimated revenues (which includes both revenues estimated to be realized during the New Venture phase and estimated revenues from the licensing of the resulting “on-the-shelf” data survey) and multiplying that percentage by the total cost of the project (the sales forecast method). The Company considers a multi-client data survey to be complete when all work on the creation of the seismic data is finished and that data survey is available for licensing. Once a multi-client data survey is complete, the data survey is considered “on-the-shelf” and the Company’s method of amortization is then the greater of (i) the sales forecast method or (ii) the straight-line basis over a four-year period. The greater amount of amortization resulting from the sales forecast method or the straight-line amortization policy is applied on a cumulative basis at the individual survey level. Under this policy, the Company first records amortization using the sales forecast method. The cumulative amortization recorded for each survey is then compared with the cumulative straight-line amortization. The four-year period utilized in this cumulative comparison commences when the data survey is determined to be complete. If the cumulative straight-line amortization is higher for any specific survey, additional amortization expense is recorded, resulting in accumulated amortization being equal to the cumulative straight-line amortization for such survey. The Company has determined the amortization period of four years based upon its historical experience that indicates that the majority of its revenues from multi-client surveys are derived during the acquisition and processing phases and during four years subsequent to survey completion. The Company estimates the ultimate revenue expected to be derived from a particular seismic data survey over its estimated useful economic life to determine the costs to amortize, if greater than straight-line amortization. That estimate is made by the Company at the project’s initiation. For a completed multi-client survey, the Company reviews the estimate quarterly. If during any such review, the Company determines that the ultimate revenue for a survey is expected to be materially more or less than the original estimate of ultimate revenue for such survey, the Company decreases or increases (as the case may be) the amortization rate attributable to the future revenue from such survey. In addition, in connection with such reviews, the Company evaluates the recoverability of the multi-client data library, and, if required, records an impairment charge with respect to such data.
Equity Method Investment	Equity Method Investment The Company determined that INOVA Geophysical is a variable interest entity because the Company’s voting rights with respect to INOVA Geophysical are not proportionate to its ownership interest and substantially all of INOVA Geophysical’s activities are conducted on behalf of the Company and BGP, a related party to the Company. The Company is not the primary beneficiary of INOVA Geophysical because it does not have the power to direct the activities of INOVA Geophysical that most significantly impact its economic performance. Accordingly, the Company does not consolidate INOVA Geophysical, but instead accounts for INOVA Geophysical using the equity method of accounting. Under this method, an investment is carried at the acquisition cost, plus the Company’s equity in undistributed earnings or losses since acquisition, less distributions received.
Noncontrolling Interests	Noncontrolling Interests The Company has non-redeemable noncontrolling interests. Non-redeemable noncontrolling interests in majority-owned affiliates are reported as a separate component of equity in “Noncontrolling interests” in the Consolidated Balance Sheets. Net income attributable to noncontrolling interests is stated separately in the Consolidated Statements of Operations. The activity for this noncontrolling interest relates to proprietary processing projects in Brazil.
Goodwill	Goodwill Goodwill is allocated to reporting units, which are either the operating segment or one reporting level below the operating segment. For purposes of performing the impairment test for goodwill, the Company established the following reporting units: E&P Technology & Services, Optimization Software & Services and Devices. The Company is required to evaluate the carrying value of its goodwill at least annually for impairment, or more frequently if facts and circumstances indicate that it is more likely than not impairment has occurred. The Company formally evaluates the carrying value of its goodwill for impairment as of December 31 for each of its reporting units. The Company first performs a qualitative assessment by evaluating relevant events or circumstances to determine whether it is more likely than not that the fair value of a reporting unit exceeds its carrying amount. If the Company is unable to conclude qualitatively that it is more likely than not that a reporting unit’s fair value exceeds its carrying value, then it will use a two-step quantitative assessment of the fair value of a reporting unit. To determine the fair value of these reporting units, the Company uses a discounted future returns valuation model, which includes a variety of level 3 inputs. The key inputs for the model include the operational three -year forecast for the Company and the then-current market discount factor. Additionally, the Company compares the sum of the estimated fair values of the individual reporting units less consolidated debt to the Company’s overall market capitalization as reflected by the Company’s stock price. If the carrying value of a reporting unit that includes goodwill is determined to be more than the fair value of the reporting unit, there exists the possibility of impairment of goodwill. An impairment loss of goodwill is measured in two steps by first allocating the fair value of the reporting unit to net assets and liabilities including recorded and unrecorded intangible assets to determine the implied carrying value of goodwill. The next step is to measure the difference between the carrying value of goodwill and the implied carrying value of goodwill, and, if the implied carrying value of goodwill is less than the carrying value of goodwill, an impairment loss is recorded equal to the difference.
Revenue from contracts with customers	Revenue From Contracts With Customers On January 1, 2018, the Company adopted Accounting Standards Codification Topic 606 - “Revenue from Contracts with Customers” and all the related amendments (“ASC 606”), using the modified retrospective method. This standard applies to all contracts with customers, except for contracts that are within the scope of other standards, such as leases, insurance, collaborative arrangements and financial instruments. The adoption of ASC 606 did not have a material impact on the Consolidated Balance Sheets or Consolidated Statements of Operations for any of our reporting segments.
Research, Development and Engineering	Research, Development and Engineering Research, development and engineering costs primarily relate to activities that are designed to improve the quality of the subsurface image and overall acquisition economics of the Company’s customers. The costs associated with these activities are expensed as incurred. These costs include prototype material and field testing expenses, along with the related salaries and stock-based compensation, facility costs, consulting fees, tools and equipment usage and other miscellaneous expenses associated with these activities.
Stock-Based Compensation	Stock-Based Compensation The Company accounts for all stock-based payment awards issued to employees and directors, including employee stock options, restricted stocks units, restricted stocks and stock appreciation rights under the provisions of ASC 718 “Compensation – Stock Compensation ” (“ASC 718”). The Company estimates the value of stock-based payment awards on the date of grant using an option pricing model such as Black-Scholes or Monte Carlo simulation. The determination of the fair value of stock-based payment awards is affected by the Company’s stock price as well as assumptions regarding a number of subjective variables. These variables include, but are not limited to, expected stock price volatility over the term of the awards, actual and projected stock-based instrument exercise behaviors, risk-free interest rate and expected dividends. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. The Company recognizes stock-based compensation expense on the straight-line basis over the requisite service period of each award that are ultimately expected to vest.
Income Taxes	Income Taxes Income taxes are accounted for under the liability method. Deferred income tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, including operating loss and tax credit carryforwards. Deferred income tax assets and liabilities are measured using enacted tax rates expected to apply in the years in which those temporary differences are expected to be recovered or settled. The Company records a valuation allowance when it is more likely than not that all or a portion of deferred tax assets will not be realized (see Footnote 7 “ Income Taxes ”). The effect on deferred income tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date.
Debt issuance cost	Debt Issuance Costs The Company presents debt issuance costs related to a debt liability as a direct deduction from the carrying amount of that debt liability on the Consolidated Balance Sheets and amortizes such costs using the effective interest method whereas debt issuance costs related to line of credit arrangement is presented within “Other assets” on the Consolidated Balance Sheets and amortized ratably over the term of the line of credit arrangement, regardless of whether there are any outstanding borrowings on the line of credit arrangeme
Foreign Currency Gains and Losses	Foreign Currency Gains and Losses Assets and liabilities of the Company’s subsidiaries operating outside the United States that have a functional currency other than the U.S. dollar have been translated to U.S. dollars using the exchange rate in effect at the balance sheet date. Results of foreign operations have been translated using the average exchange rate during the periods of operation. Resulting translation adjustments have been recorded as a component of Accumulated Other Comprehensive Loss . Foreign currency transaction gains and losses, as they occur, are included in “Other income (expense), net” on the Consolidated Statements of Operations.
Concentration of Foreign Sales Risk	Concentration of Foreign Sales Risk The majority of the Company’s foreign sales are denominated in U.S. dollars. For 2018 , 2017 and 2016 , international sales comprised 75% , 76% and 78% , respectively, of total net revenues. Since 2008, global economic problems and uncertainties have generally increased in scope and nature. The volatility in oil prices have continued to impact the global market throughout 2018. To the extent that world events or economic conditions negatively affect the Company’s future sales to customers in many regions of the world, as well as the collectability of the Company’s existing receivables, the Company’s future results of operations, liquidity and financial condition would be adversely affected.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-2, “ Leases (Topic 842)” which introduces the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous guidance. The guidance will be effective for annual reporting periods beginning after December 15, 2018 and interim periods within those fiscal years with early adoption permitted. The Company will adopt ASU 2016-2 on January 1, 2019 using the modified retrospective method. The Company has completed its evaluation of operating leases related to offices, processing centers, warehouse spaces and, to a lesser extent, certain equipment. The Company expects the adoption of the standard will result in approximately $50 million to $60 million in right-of-use assets and lease obligations on the Consolidated Balance Sheets. The Company expects the Income Statement recognition to appear similar to its current methodology. The Company will elect the practical expedients upon transition which will retain the lease classification for leases and any unamortized initial direct costs that existed prior to the adoption of the standard. On January 1, 2018, the Company adopted ASC 606 and all the related amendments using the modified retrospective method. The adoption did not have a material impact to the Company’s revenue recognition policy under the previous standard and adoption of the new standard did not result in an adjustment to the Company’s beginning retained earnings balance. On January 1, 2018, the Company adopted ASU 2016-18, Statement of Cash Flows “ Restricted Cash (a consensus of the FASB Emerging Issues Task Force) ”, using a retrospective transition method to each period presented. The new standard no longer requires the Company to present transfers between cash and cash equivalents and restricted cash in the statements of cash flows. Adoption of the new standard resulted in a decrease of $0.4 million and $0.6 million in net cash provided by operating activities as previously reported for the years ended December 31, 2017 and 2016, respectively. See the Consolidated Statements of Cash Flows above which includes a reconciliation of cash and cash equivalents to total cash, cash equivalents, and restricted cash. In June 2016, the FASB issued ASU No. 2016-13, “ Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments.” The guidance will replace the incurred loss impairment methodology under 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 guidance is effective for public companies for interim and annual periods beginning after December 15, 2019, with early adoption permitted for interim and annual periods beginning after December 15, 2018. The Company is in the initial stages of evaluating the impact of this standard on the Consolidated Financial Statements.

Summary of Significant Accoutin

Summary of Significant Accouting Policies (Tables)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Property, Plant, Equipment and Seismic Rental Equipment	Property, plant, equipment and seismic rental equipment are stated at cost. Depreciation expense is provided straight-line over the following estimated useful lives: Years Machinery and equipment 3-7 Buildings 5-25 Seismic rental equipment 3-5 Leased equipment and other 3-10 A summary of property, plant, equipment and seismic rental equipment follows (in thousands): December 31, 2018 2017 Buildings $ 15,707 $ 15,822 Machinery and equipment 132,135 145,654 Seismic rental equipment 1,423 1,677 Furniture and fixtures 3,859 3,869 Other 30,104 28,965 Total 183,228 195,987 Less accumulated depreciation (133,634 ) (143,834 ) Less impairment of long-lived assets (36,553 ) — Property, plant, equipment and seismic rental equipment, net $ 13,041 $ 52,153
Schedule of Multi-Client Data Library	At December 31, 2018 and 2017 , multi-client data library costs and accumulated amortization consisted of the following (in thousands): December 31, 2018 2017 Gross costs of multi-client data creation $ 972,309 $ 939,077 Less accumulated amortization (776,860 ) (727,872 ) Less impairments to multi-client data library (121,905 ) (121,905 ) Multi-client data library, net $ 73,544 $ 89,300

Segment and Geographic Inform_2

Segment and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Schedule of Segment Information	A summary of segment information follows (in thousands): Years Ended December 31, 2018 2017 2016 Net revenues: E&P Technology & Services: New Venture $ 69,685 $ 100,824 $ 27,362 Data Library 47,095 40,016 39,989 Total multi-client revenues 116,780 140,840 67,351 Imaging Services 19,740 16,409 25,538 Total $ 136,520 $ 157,249 $ 92,889 Operations Optimization: Devices $ 22,396 $ 23,610 $ 26,746 Optimization Software & Services 21,129 16,695 16,756 Total $ 43,525 $ 40,305 $ 43,502 Other $ — $ — $ 36,417 (a) Total $ 180,045 $ 197,554 $ 172,808 Gross profit (loss): E&P Technology & Services $ 43,369 $ 65,196 $ 4,708 Operations Optimization 22,293 20,076 21,745 Segment gross profit 65,662 85,272 26,453 Other (b) (6,042 ) (9,633 ) 9,579 Total $ 59,620 $ 75,639 $ 36,032 Gross margin: E&P Technology & Services 32 % 41 % 5 % Operations Optimization 51 % 50 % 50 % Segment gross margin 36 % 43 % 15 % Other (3 )% (5 )% 6 % Total 33 % 38 % 21 % Income (loss) from operations: E&P Technology & Services $ 21,758 $ 42,505 $ (16,446 ) Operations Optimization 7,295 8,022 9,652 Support and other (c) (83,325 ) (d) (59,226 ) (36,377 ) Loss from operations (54,272 ) (8,699 ) (43,171 ) Interest expense, net (12,972 ) (16,709 ) (18,485 ) Other income (expense), net (436 ) (3,945 ) 1,350 Loss before income taxes $ (67,680 ) $ (29,353 ) $ (60,306 ) (a) Relates to revenues of the previously reported Ocean Bottom Integrated Technologies segment. (b) Relates to gross profit (loss) of previously reported Ocean Bottom Integrated Technologies segment. (c) Includes loss from operations of previously reported Ocean Bottom Integrated Technologies segment of $47.6 million , $16.3 million and $1.8 million for the years ended December 31, 2018, 2017 and 2016, respectively, which includes item (b) above and operating expenses of $41.6 million , $6.7 million and $11.3 million for the years ended December 31, 2018, 2017 and 2016. (d) Includes a charge of $36.6 million to write-down the cable-based ocean bottom acquisition technologies associated with the previously reported Ocean Bottom Integrated Technologies segment. This impairment relates to property, plant, equipment and seismic rental equipment of $21.3 million within the Operations Optimization segment and $15.3 million within the previously reported Ocean Bottom Integrated Technologies segment. Years Ended December 31, 2018 2017 2016 Depreciation and amortization (including multi-client data library): E&P Technology & Services $ 51,673 $ 53,663 $ 44,100 Operations Optimization 995 1,349 1,780 Support and other (a) 5,083 8,682 9,430 Total $ 57,751 $ 63,694 $ 55,310
Schedule of Depreciation and Amortization by Segments	Years Ended December 31, 2018 2017 2016 Depreciation and amortization (including multi-client data library): E&P Technology & Services $ 51,673 $ 53,663 $ 44,100 Operations Optimization 995 1,349 1,780 Support and other (a) 5,083 8,682 9,430 Total $ 57,751 $ 63,694 $ 55,310
Segment Reporting of Assets by Segments and Geographical Areas	December 31, 2018 2017 Total assets: E&P Technology & Services $ 165,132 $ 156,555 Operations Optimization 51,783 74,361 Support and other (a) 27,834 70,153 Total $ 244,749 (b) $ 301,069 (a) Includes total assets of previously reported Ocean Bottom Integrated Technologies segment of $1.2 million and $20.8 million for the year ended December 31, 2018 and 2017, respectively. (b) Balance is net of impairment charge of $36.6 million related to the cable-based ocean bottom acquisition technologies. A summary of total assets by geographic area follows (in thousands): December 31, 2018 2017 North America $ 86,614 $ 116,598 Latin America 69,418 55,661 Middle East 52,037 70,308 Europe 31,566 51,876 Other 5,114 6,626 Total $ 244,749 $ 301,069
Schedule of Fixed Assets Less Accumulated Depreciation by Geographic Area	A summary of property, plant, equipment and seismic equipment less accumulated depreciation and impairment by geographic area follows (in thousands): December 31, 2018 2017 North America $ 11,663 $ 10,609 Europe 1,140 20,725 Latin America 143 170 Middle East 36 20,543 Other 59 106 Total $ 13,041 (a) $ 52,153 (a) Balance is net of impairment charge of $36.6 million related to the cable-based ocean bottom acquisition technologies.
Summary of Net Revenues by Geographic Area	A summary of net revenues by geographic area follows (in thousands): Years Ended December 31, 2018 2017 2016 Latin America $ 68,871 $ 68,241 $ 24,090 North America 44,474 48,120 38,005 Europe 31,077 44,930 41,674 Asia Pacific 17,817 18,896 16,226 Africa 10,837 6,837 41,417 Middle East 5,526 2,308 9,467 Commonwealth of Independent States 1,443 8,222 1,929 Total $ 180,045 $ 197,554 $ 172,808

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Contract with Customer, Asset and Liability	The following table is a summary of deferred revenues (in thousands): December 31, 2018 2017 New Venture $ 5,797 $ 6,548 Imaging Services 307 676 Devices 626 633 Optimization Software & Services 980 1,053 Total $ 7,710 $ 8,910 The changes in deferred revenues were as follows (in thousands): Deferred revenue at December 31, 2017 $ 8,910 Cash collected in excess of revenue recognized 25,234 Recognition of deferred revenue (a) (26,434 ) Deferred revenue at December 31, 2018 $ 7,710 (a) The majority of deferred revenue recognized relates to Company’s Ventures group. The following table is a summary of unbilled receivables (in thousands): December 31, 2018 2017 New Venture $ 38,430 $ 33,183 Imaging Services 5,075 4,121 Devices 527 — Total $ 44,032 $ 37,304 The changes in unbilled receivables were as follows (in thousands): Unbilled receivables at December 31, 2017 $ 37,304 Recognition of unbilled receivables 153,611 Revenues billed to customers (146,883 ) Unbilled receivables at December 31, 2018 $ 44,032

Long-term Debt and Lease Obli_2

Long-term Debt and Lease Obligations (Tables)	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Obligations	The following is a summary of long-term debt and lease obligation (in thousands): December 31, 2018 2017 Senior secured second-priority lien notes (maturing December 15, 2021) $ 120,569 $ 120,569 Senior secured third-priority lien notes (redeemed March 26, 2018) — 28,497 Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a) — 10,000 Equipment capital leases 2,938 279 Other debt 1,159 1,382 Costs associated with issuances of debt (2,925 ) (3,983 ) Total 121,741 156,744 Current portion of long-term debt and lease obligations (2,228 ) (40,024 ) Non-current portion of long-term debt and lease obligations $ 119,513 $ 116,720 (a) The maturity of the revolving credit facility will accelerate to December 15, 2021 if the Company is unable to repay or extend the maturity of the Second Lien Notes.
Debt Instrument Redemption Percentages	On or after December 15, 2019, the Company may on one or more occasions redeem all or a part of the Second Lien Notes at the redemption prices set forth below, plus accrued and unpaid interest and special interest, if any, on the Second Lien Notes redeemed during the twelve-month period beginning on December 15th of the years indicated below: Date Percentage 2019 105.500% 2020 103.500% 2021 and thereafter 100.000%
Equipment Capital Leases	A summary of future principal obligations under long-term debt and equipment capital lease obligations follows (in thousands): Years Ending December 31, Short-Term and Long-Term Debt Capital Lease Obligations Other Financing Total 2019 $ — $ 1,069 1,159 $ 2,228 2020 — 1,135 — 1,135 2021 120,569 734 — 121,303 Total $ 120,569 $ 2,938 $ 1,159 $ 124,666

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Sources of income (loss) before income taxes	The sources of income (loss) before income taxes are as follows (in thousands): Years Ended December 31, 2018 2017 2016 Domestic $ (59,212 ) $ (12,487 ) $ (41,246 ) Foreign (8,468 ) (16,866 ) (19,060 ) Total $ (67,680 ) $ (29,353 ) $ (60,306 )
Components of income taxes	Components of income taxes are as follows (in thousands): Years Ended December 31, 2018 2017 2016 Current: Federal $ — $ (166 ) $ — State and local 65 116 28 Foreign 8,905 5,494 5,574 Deferred: Federal (346 ) (1,263 ) — Foreign (5,906 ) (4,157 ) (1,181 ) Total income tax expense $ 2,718 $ 24 $ 4,421
Reconciliation of the expected income tax expense on income (loss) before income taxes using the statutory federal income tax	A reconciliation of the expected income tax expense on income (loss) before income taxes using the statutory federal income tax rate of 21% for 2018 and 35% for 2017 and 2016 to income tax expense follows (in thousands): Years Ended December 31, 2018 2017 2016 Expected income tax expense at 21% for 2018 and 35% for 2017 and 2016 $ (14,213 ) $ (10,274 ) $ (21,107 ) Foreign tax rate differential 74 (2,914 ) 5,932 Foreign tax differences 4,703 (5,610 ) (4,828 ) Global intangible low tax income inclusion 3,443 — — State and local taxes 65 116 28 Nondeductible expenses 1,604 4,308 (259 ) Change in U.S. tax rate — 77,410 — Expired capital loss — 1,114 1,321 Valuation allowance: Valuation allowance on expiring capital losses — (1,114 ) (1,321 ) Valuation allowance on operations 7,042 (63,012 ) 24,655 Total income tax expense $ 2,718 $ 24 $ 4,421
Tax effects of the cumulative temporary differences resulting in the net deferred income tax asset (liability)	The tax effects of the cumulative temporary differences resulting in the net deferred income tax asset (liability) are as follows (in thousands): December 31, 2018 2017 Deferred income tax assets: Accrued expenses $ 1,126 $ 1,976 Allowance accounts 6,415 2,960 Net operating loss carryforward 96,854 87,705 Equity method investment 35,292 35,292 Original issue discount 8,073 9,624 Interest limitation 5,845 — Basis in identified intangibles 4,146 9,408 Tax credit carryforwards 5,345 6,929 Contingency accrual — 788 Other 4,600 4,035 Total deferred income tax asset 167,696 158,717 Valuation allowance (160,505 ) (153,463 ) Net deferred income tax asset 7,191 5,254 Deferred income tax liabilities: Unbilled receivables — (3,501 ) Total deferred income tax asset, net $ 7,191 $ 1,753
Aggregate changes in gross amount of unrecognized tax benefits	During 2018 , 2017 and 2016 , the aggregate changes in the Company’s total gross amount of unrecognized tax benefits are summarized as follows (in thousands): Years Ended December 31, 2018 2017 2016 Beginning balance $ 447 $ 1,299 $ 1,250 Increases in unrecognized tax benefits – current year positions — 59 49 Decreases in unrecognized tax benefits – prior year position — (911 ) — Ending balance $ 447 $ 447 $ 1,299

Other Income (Expense) (Tables)

Other Income (Expense) (Tables)	12 Months Ended
	Dec. 31, 2018
Other Income and Expenses [Abstract]
Schedule of Other Income (Expense)	A summary of other income (expense) follows (in thousands): Years Ended December 31, 2018 2017 2016 (Accrual for) reduction of loss contingency related to legal proceedings (Footnote 8) $ — $ (5,000 ) $ 1,168 Recovery of INOVA bad debts — 844 3,983 Loss on bond exchange — — (2,182 ) Other income (expense) (436 ) 211 (1,619 ) Total other income (expense), net $ (436 ) $ (3,945 ) $ 1,350

Details of Selected Balance S_2

Details of Selected Balance Sheet Accounts (Tables)	12 Months Ended
	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of accounts receivable	A summary of accounts receivable follows (in thousands): December 31, 2018 2017 Accounts receivable, principally trade $ 26,558 $ 20,050 Less allowance for doubtful accounts (430 ) (572 ) Accounts receivable, net $ 26,128 $ 19,478
Summary of inventories	A summary of inventories follows (in thousands): December 31, 2018 2017 Raw materials and purchased subassemblies $ 20,011 $ 20,448 Work-in-process 1,032 1,146 Finished goods 8,111 7,953 Less reserve for excess and obsolete inventories (15,024 ) (15,039 ) Inventories, net $ 14,130 $ 14,508
Summary of property, plant, equipment and seismic rental equipment	Property, plant, equipment and seismic rental equipment are stated at cost. Depreciation expense is provided straight-line over the following estimated useful lives: Years Machinery and equipment 3-7 Buildings 5-25 Seismic rental equipment 3-5 Leased equipment and other 3-10 A summary of property, plant, equipment and seismic rental equipment follows (in thousands): December 31, 2018 2017 Buildings $ 15,707 $ 15,822 Machinery and equipment 132,135 145,654 Seismic rental equipment 1,423 1,677 Furniture and fixtures 3,859 3,869 Other 30,104 28,965 Total 183,228 195,987 Less accumulated depreciation (133,634 ) (143,834 ) Less impairment of long-lived assets (36,553 ) — Property, plant, equipment and seismic rental equipment, net $ 13,041 $ 52,153
Summary of accrued expenses	A summary of other long-term liabilities follows (in thousands): December 31, 2018 2017 Deferred lease liabilities 11,465 12,811 Other 429 1,115 Total $ 11,894 $ 13,926 A summary of accrued expenses follows (in thousands): December 31, 2018 2017 Compensation, including compensation-related taxes and commissions $ 14,502 $ 19,809 Accrued multi-client data library acquisition costs 3,746 5,104 Income tax payable 7,577 1,868 Accrual for loss contingency related to legal proceedings (Footnote 8) — 3,750 Other 5,586 8,166 Total $ 31,411 $ 38,697

Goodwill (Tables)

Goodwill (Tables)	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in the carrying amount of goodwill	The following is a summary of the changes in the carrying amount of goodwill for the years ended December 31, 2018 and 2017 (in thousands): E&P Technology & Services Optimization Software & Services Total Balance at January 1, 2017 $ 2,943 $ 19,265 $ 22,208 Impact of foreign currency translation adjustments — 1,881 1,881 Balance at December 31, 2017 2,943 21,146 24,089 Impact of foreign currency translation adjustments — (1,174 ) (1,174 ) Balance at December 31, 2018 $ 2,943 $ 19,972 $ 22,915

Stockholder's Equity and Stoc_2

Stockholder's Equity and Stock-based Compensation (Tables)	12 Months Ended
	Dec. 31, 2018
Share-based Payment Arrangement [Abstract]
Transactions Under the Stock Option Plans	Transactions under the stock option plans are summarized as follows: Option Price per Share Outstanding Vested Available for Grant January 1, 2016 $34.20 - $245.85 560,797 384,305 97,003 Increase in shares authorized — — — 1,150,940 Granted 3.10 415,000 — (415,000 ) Vested — — 67,480 — Cancelled/forfeited 3.10 - 245.85 (128,162 ) (103,432 ) 18,895 Restricted stock granted out of option plans — — — (259,300 ) Restricted stock forfeited or cancelled for employee minimum income taxes and returned to the plans — — — 7,182 December 31, 2016 $3.10 - $245.85 847,635 348,353 599,720 Granted 13.15 156,000 — (156,000 ) Vested — — 149,537 — Exercised 3.10 (15,000 ) (15,000 ) — Cancelled/forfeited 3.10 - 245.85 (98,294 ) (47,612 ) 82,118 Restricted stock granted out of option plans — — — (59,500 ) Restricted stock forfeited or cancelled for employee minimum income taxes and returned to the plans — — — 22,065 December 31, 2017 3.10 - 245.85 890,341 435,278 488,403 Increase in shares authorized — — — 1,200,000 Granted 24.50 10,000 — (10,000 ) Vested — — 153,944 — Exercised 3.10 (70,086 ) (70,086 ) — Cancelled/forfeited 3.10 - 245.85 (44,365 ) (44,231 ) 2,568 Restricted stock granted out of option plans — — — (996,775 ) Restricted stock forfeited or cancelled for employee minimum income taxes and returned to the plans — — — 48,524 December 31, 2018 $3.10 - $151.35 785,890 474,905 732,720
Summary of Stock Options Outstanding	Stock options outstanding at December 31, 2018 are summarized as follows: Option Price per Share Outstanding Weighted Average Exercise Price of Outstanding Options Weighted Average Remaining Contract Life Vested Weighted Average Exercise Price of Vested Options $3.10 - $57.90 558,997 $ 15.64 7.2 years 248,012 $ 24.32 $61.05 - $71.85 75,231 $ 62.17 4.7 years 75,231 $ 62.17 $81.60 - $99.60 108,610 $ 88.94 3.6 years 108,610 $ 88.94 $106.05 - $151.35 43,052 $ 108.84 2.3 years 43,052 $ 108.84 Totals 785,890 $ 35.33 5.4 years 474,905 $ 52.76
Additional Information Related to the Company's Stock Options	Additional information related to the Company’s stock options follows: Number of Shares Weighted Average Exercise Price Weighted Average Grant Date Fair Value Weighted Average Remaining Contractual Life Aggregate Intrinsic Value (000’s) Total outstanding at January 1, 2018 890,341 $ 36.17 6.4 years $ 6,774 Options granted 10,000 $ 24.50 $ 15.23 Options exercised (70,086 ) $ 3.10 Options cancelled (134 ) $ 61.05 Options forfeited (44,231 ) $ 100.85 Total outstanding at December 31, 2018 785,890 $ 35.33 5.4 years $ 572 Options exercisable and vested at December 31, 2018 474,905 $ 52.76 5 years $ 213
Schedule of Valuation Assumptions	The Company calculated the fair value of each stock option on the date of grant using the Black-Scholes option pricing model. The following assumptions were used for each respective period: Years Ended December 31, 2018 2017 2016 Risk-free interest rates 2.78% 2.14% 1.3% Expected lives (in years) 5.0 5.0 5.5 Expected dividend yield —% —% —% Expected volatility 73.67% 74.41% 78.76% The following assumptions were used: Risk-free interest rates 3.0 % Expected lives (in years) 5.31 Expected dividend yield — % Expected volatility 82.9 %
Status of the Company's Restricted Stock and Restricted Stock Unit Awards	The status of the Company’s restricted stock and restricted stock unit awards for 2018 follows: Number of Shares/Units Total nonvested at January 1, 2018 201,702 Granted 996,775 Vested (151,852 ) Forfeited (2,500 ) Total nonvested at December 31, 2018 1,044,125
Schedule of Share-based Compensation, Stock Appreciation Rights Award Activity	Additional information related to the Company's SARs follows: Number of Shares Weighted Average Exercise Price Weighted Average Grant Date Fair Value Weighted Average Remaining Contractual Life Aggregate Intrinsic Value (000’s) Total outstanding at January 1, 2016 216,532 $ 34.67 SARs granted 1,210,000 $ 3.10 $ 17.55 SARs cancelled (10,399 ) $ 34.20 Total outstanding at December 31, 2016 1,416,133 $ 7.70 SARs exercised (713,330 ) $ 3.10 SARs cancelled (136,939 ) $ 7.70 Total outstanding at December 31, 2017 565,864 $ 13.49 SARs granted 960,009 $ 8.85 8.85 SARs exercised (34,999 ) $ 3.10 SARs forfeited (9,333 ) $ 45.00 Total outstanding at December 31, 2018 1,481,541 $ 10.53 8.1 years $ 718 SARs exercisable and vested at December 31, 2018 — $ —
Summary of Stock-based Compensation Expense	The following tables summarizes stock-based compensation expense for the years ended December 31, 2018 , 2017 and 2016 as follows (in thousands): Years Ended December 31, 2018 2017 2016 Stock-based compensation expense $ 3,337 $ 2,552 $ 3,267 Tax benefit related thereto (698 ) (862 ) (1,168 ) Stock-based compensation expense, net of tax $ 2,639 $ 1,690 $ 2,099 Years Ended December 31, 2018 2017 2016 Stock appreciation rights expense $ 822 $ 6,611 547 Tax benefit related thereto (173 ) (2,314 ) (191 ) Stock appreciation rights expense, net of tax $ 649 $ 4,297 $ 356

Supplemental Cash Flow Inform_2

Supplemental Cash Flow Information and Non-Cash Activity (Tables)	12 Months Ended
	Dec. 31, 2018
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information and Non-cash Activity	Supplemental disclosure of cash flow information follows (in thousands): Years Ended December 31, 2018 2017 2016 Cash paid during the period for: Interest $ 5,731 $ 14,181 $ 15,691 Income taxes 3,260 7,030 4,474 Non-cash items from investing and financing activities: Purchase of computer equipment financed through capital leases 3,297 — — Leasehold improvement paid by landlord — — 955 Issuance of stock in bond exchange — — 10,741 Transfer of inventory to property, plant and equipment — — 17,662 (a) Investment in multi-client data library financed through trade payables 4,956 9,059 — (a) This transfer of $17.7 million of inventory to property, plant, equipment and seismic rental equipment in December 2016, relates to ocean bottom seismic equipment manufactured by the Company to be deployed in the acquisition of ocean bottom seismic data.

Operating Leases (Tables)

Operating Leases (Tables)	12 Months Ended
	Dec. 31, 2018
Leases, Operating [Abstract]
Future Rental Commitments Over the Next Five Years Under Non-cancelable Operating Leases	A summary of future rental commitments over the next five years under non-cancelable operating leases follows (in thousands): Years Ending December 31, 2019 $ 13,248 2020 12,857 2021 11,075 2022 10,821 2023 9,205 Total $ 57,206

Selected Quarterly Informatio_2

Selected Quarterly Information (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Summary of selected quarterly information	A summary of selected quarterly information follows (in thousands, except per share amounts): Three Months Ended March 31, 2018 June 30, 2018 September 30, 2018 December 31, 2018 Service revenues $ 25,086 $ 15,752 $ 37,105 $ 61,095 Product revenues 8,422 8,991 10,095 13,499 Total net revenues 33,508 24,743 47,200 74,594 Gross profit (loss) 6,853 (1,517 ) 16,475 37,809 Loss from operations (12,640 ) (22,519 ) (2,452 ) (16,661 ) Interest expense, net (3,836 ) (2,911 ) (3,022 ) (3,203 ) Other income (expense), net (791 ) 84 91 180 Income tax expense (benefit) 1,072 154 2,079 (587 ) Net income attributable to noncontrolling interests (87 ) (366 ) (74 ) (246 ) Net loss applicable to ION $ (18,426 ) $ (25,866 ) $ (7,536 ) $ (19,343 ) Net loss per share: Basic $ (1.44 ) $ (1.86 ) $ (0.54 ) $ (1.38 ) Diluted $ (1.44 ) $ (1.86 ) $ (0.54 ) $ (1.38 ) Three Months Ended March 31, 2017 June 30, 2017 September 30, 2017 December 31, 2017 Service revenues $ 23,828 $ 34,454 $ 52,615 $ 48,513 Product revenues 8,728 11,547 8,480 9,389 Total net revenues 32,556 46,001 61,095 57,902 Gross profit 6,101 15,618 30,109 23,811 Income (loss) from operations (13,912 ) (3,572 ) 9,936 (1,151 ) Interest expense, net (4,464 ) (4,241 ) (3,959 ) (4,045 ) Other income (expense), net (5,068 ) 192 722 209 Income tax expense (benefit) (418 ) 2,402 1,686 (3,646 ) Net income attributable to noncontrolling interests (316 ) (418 ) (78 ) (53 ) Net income (loss) applicable to ION $ (23,342 ) $ (10,441 ) $ 4,935 $ (1,394 ) Net income (loss) per share: Basic $ (1.98 ) $ (0.88 ) $ 0.42 $ (0.12 ) Diluted $ (1.98 ) $ (0.88 ) $ 0.41 $ (0.12 )

Condensed Consolidating Finan_2

Condensed Consolidating Financial Information (Tables)	12 Months Ended
	Dec. 31, 2018
Condensed Financial Information Disclosure [Abstract]
Condensed Balance Sheet	December 31, 2018 Balance Sheet ION Geophysical Corporation The Guarantors All Other Subsidiaries Consolidating Adjustments Total Consolidated (In thousands) ASSETS Current assets: Cash and cash equivalents $ 13,782 $ 47 $ 19,722 $ — $ 33,551 Accounts receivable, net 8 17,349 8,771 — 26,128 Unbilled receivables — 12,697 31,335 — 44,032 Inventories — 8,721 5,409 — 14,130 Prepaid expenses and other current assets 3,891 1,325 2,566 — 7,782 Total current assets 17,681 40,139 67,803 — 125,623 Deferred income tax asset 805 6,261 125 — 7,191 Property, plant, equipment and seismic rental equipment, net 489 8,922 3,630 — 13,041 Multi-client data library, net — 70,380 3,164 — 73,544 Investment in subsidiaries 836,002 247,359 — (1,083,361 ) — Goodwill — — 22,915 — 22,915 Intercompany receivables — 305,623 66,021 (371,644 ) — Other assets 1,723 643 69 — 2,435 Total assets $ 856,700 $ 679,327 $ 163,727 $ (1,455,005 ) $ 244,749 LIABILITIES AND EQUITY Current liabilities: Current maturities of long-term debt $ 1,159 $ 1,069 $ — $ — $ 2,228 Accounts payable 2,407 29,602 2,904 — 34,913 Accrued expenses 7,011 10,036 14,364 — 31,411 Accrued multi-client data library royalties — 29,040 216 — 29,256 Deferred revenue — 6,515 1,195 — 7,710 Total current liabilities 10,577 76,262 18,679 — 105,518 Long-term debt, net of current maturities 117,644 1,869 — — 119,513 Intercompany payables 721,817 — — (721,817 ) — Other long-term liabilities 430 5,698 5,766 — 11,894 Total liabilities 850,468 83,829 24,445 (721,817 ) 236,925 Equity: Common stock 140 290,460 47,776 (338,236 ) 140 Additional paid-in capital 952,626 180,700 203,908 (384,608 ) 952,626 Accumulated earnings (deficit) (926,092 ) 390,691 (12,475 ) (378,216 ) (926,092 ) Accumulated other comprehensive income (loss) (20,442 ) 4,324 (22,023 ) 17,699 (20,442 ) Due from ION Geophysical Corporation — (270,677 ) (79,496 ) 350,173 — Total stockholders’ equity 6,232 595,498 137,690 (733,188 ) 6,232 Noncontrolling interests — — 1,592 — 1,592 Total equity 6,232 595,498 139,282 (733,188 ) 7,824 Total liabilities and equity $ 856,700 $ 679,327 $ 163,727 $ (1,455,005 ) $ 244,749 December 31, 2017 Balance Sheet ION Geophysical Corporation The Guarantors All Other Subsidiaries Consolidating Adjustments Total Consolidated (In thousands) ASSETS Current assets: Cash and cash equivalents $ 39,344 $ 66 $ 12,646 $ — $ 52,056 Accounts receivable, net 50 12,496 6,932 — 19,478 Unbilled receivables — 34,484 2,820 — 37,304 Inventories — 8,686 5,822 — 14,508 Prepaid expenses and other current assets 2,427 4,530 686 — 7,643 Total current assets 41,821 60,262 28,906 — 130,989 Deferred income tax asset 1,264 336 153 — 1,753 Property, plant, equipment and seismic rental equipment, net 511 7,170 44,472 — 52,153 Multi-client data library, net — 81,442 7,858 — 89,300 Investment in subsidiaries 693,679 321,934 — (1,015,613 ) — Goodwill — — 24,089 — 24,089 Intercompany receivables — 162,017 60,394 (222,411 ) — Other assets 686 1,811 288 — 2,785 Total assets $ 737,961 $ 634,972 $ 166,160 $ (1,238,024 ) $ 301,069 LIABILITIES AND EQUITY Current liabilities: Current maturities of long-term debt $ 39,774 $ 250 $ — $ — $ 40,024 Accounts payable 1,774 20,982 2,195 — 24,951 Accrued expenses 12,284 16,957 9,456 — 38,697 Accrued multi-client data library royalties — 26,824 211 — 27,035 Deferred revenue — 7,231 1,679 — 8,910 Total current liabilities 53,832 72,244 13,541 — 139,617 Long-term debt, net of current maturities 116,691 29 — — 116,720 Intercompany payables 537,417 — — (537,417 ) — Other long-term liabilities 454 6,084 7,388 — 13,926 Total liabilities 708,394 78,357 20,929 (537,417 ) 270,263 Equity: Common stock 120 290,460 49,394 (339,854 ) 120 Additional paid-in capital 903,247 180,701 202,290 (382,991 ) 903,247 Accumulated earnings (deficit) (854,921 ) 317,324 (9,247 ) (308,077 ) (854,921 ) Accumulated other comprehensive income (loss) (18,879 ) 4,372 (19,681 ) 15,309 (18,879 ) Due from ION Geophysical Corporation — (236,242 ) (78,764 ) 315,006 — Total stockholders’ equity 29,567 556,615 143,992 (700,607 ) 29,567 Noncontrolling interests — — 1,239 — 1,239 Total equity 29,567 556,615 145,231 (700,607 ) 30,806 Total liabilities and equity $ 737,961 $ 634,972 $ 166,160 $ (1,238,024 ) $ 301,069
Condensed Income Statement	Year Ended December 31, 2018 Income Statement ION Geophysical Corporation The Guarantors All Other Subsidiaries Consolidating Adjustments Total Consolidated (In thousands) Total net revenues $ — $ 96,649 $ 83,396 $ — $ 180,045 Cost of goods sold — 85,186 35,239 — 120,425 Gross profit — 11,463 48,157 — 59,620 Total operating expenses 32,888 29,235 51,769 — 113,892 Loss from operations (32,888 ) (17,772 ) (3,612 ) — (54,272 ) Interest expense, net (13,010 ) (136 ) 174 — (12,972 ) Intercompany interest, net 1,124 (12,137 ) 11,013 — — Equity in earnings (losses) of investments (26,446 ) 37,219 — (10,773 ) — Other income (expense) (196 ) 116 (356 ) — (436 ) Income (loss) before income taxes (71,416 ) 7,290 7,219 (10,773 ) (67,680 ) Income tax expense (benefit) (245 ) (6,711 ) 9,674 — 2,718 Net income (loss) (71,171 ) 14,001 (2,455 ) (10,773 ) (70,398 ) Net income attributable to noncontrolling interests — — (773 ) — (773 ) Net income (loss) attributable to ION $ (71,171 ) $ 14,001 $ (3,228 ) $ (10,773 ) $ (71,171 ) Comprehensive net income (loss) $ (72,734 ) $ 13,953 $ (4,797 ) $ (8,383 ) $ (71,961 ) Comprehensive income attributable to noncontrolling interest — — (773 ) — (773 ) Comprehensive net income (loss) attributable to ION $ (72,734 ) $ 13,953 $ (5,570 ) $ (8,383 ) $ (72,734 ) Year Ended December 31, 2017 Income Statement ION Geophysical Corporation The Guarantors All Other Subsidiaries Consolidating Adjustments Total Consolidated (In thousands) Total net revenues $ — $ 148,590 $ 48,964 $ — $ 197,554 Cost of goods sold — 90,754 31,161 — 121,915 Gross profit — 57,836 17,803 — 75,639 Total operating expenses 39,000 28,020 17,318 — 84,338 Income (loss) from operations (39,000 ) 29,816 485 — (8,699 ) Interest expense, net (16,729 ) (107 ) 127 — (16,709 ) Intercompany interest, net 1,084 (6,613 ) 5,529 — — Equity in earnings (losses) of investments 27,696 67,290 — (94,986 ) — Other income (expense) (4,610 ) (407 ) 1,072 — (3,945 ) Income (loss) before income taxes (31,559 ) 89,979 7,213 (94,986 ) (29,353 ) Income tax expense (benefit) (1,317 ) (1,427 ) 2,768 — 24 Net income (loss) (30,242 ) 91,406 4,445 (94,986 ) (29,377 ) Net income attributable to noncontrolling interests — — (865 ) — (865 ) Net income (loss) attributable to ION $ (30,242 ) $ 91,406 $ 3,580 $ (94,986 ) $ (30,242 ) Comprehensive net income (loss) $ (27,373 ) $ 91,358 $ 6,550 $ (97,043 ) $ (26,508 ) Comprehensive income attributable to noncontrolling interest — — (865 ) — (865 ) Comprehensive net income (loss) attributable to ION $ (27,373 ) $ 91,358 $ 5,685 $ (97,043 ) $ (27,373 ) Year Ended December 31, 2016 Income Statement ION Geophysical Corporation The Guarantors All Other Subsidiaries Consolidating Adjustments Total Consolidated (In thousands) Total net revenues $ — $ 91,465 $ 81,343 $ — $ 172,808 Cost of goods sold — 87,660 49,116 — 136,776 Gross profit — 3,805 32,227 — 36,032 Total operating expenses 31,438 27,279 20,486 — 79,203 Income (loss) from operations (31,438 ) (23,474 ) 11,741 — (43,171 ) Interest expense, net (18,406 ) (173 ) 94 — (18,485 ) Intercompany interest, net 978 (4,397 ) 3,419 — — Equity in earnings (losses) of investments (19,756 ) 23,368 — (3,612 ) — Other income (expense) 3,528 723 (2,901 ) — 1,350 Income (loss) before income taxes (65,094 ) (3,953 ) 12,353 (3,612 ) (60,306 ) Income tax expense 54 1,337 3,030 — 4,421 Net income (loss) (65,148 ) (5,290 ) 9,323 (3,612 ) (64,727 ) Net income attributable to noncontrolling interests — — (421 ) — (421 ) Net income (loss) attributable to ION $ (65,148 ) $ (5,290 ) $ 8,902 $ (3,612 ) $ (65,148 ) Comprehensive net income (loss) $ (72,331 ) $ (5,290 ) $ 1,719 $ 4,208 $ (71,694 ) Comprehensive income attributable to noncontrolling interest — — (421 ) — (421 ) Comprehensive net income (loss) attributable to ION $ (72,331 ) $ (5,290 ) $ 1,298 $ 4,208 $ (72,115 )
Condensed Cash Flow Statement	Year Ended December 31, 2018 Statement of Cash Flows ION Geophysical Corporation The Guarantors All Other Subsidiaries Total Consolidated (In thousands) Cash flows from operating activities: Net cash provided by (used in) operating activities $ (37,659 ) $ 39,407 $ 5,350 $ 7,098 Cash flows from investing activities: Investment in multi-client data library — (25,307 ) (2,969 ) (28,276 ) Purchase of property, plant, equipment and seismic rental equipment (392 ) (959 ) (163 ) (1,514 ) Net cash used in investing activities (392 ) (26,266 ) (3,132 ) (29,790 ) Cash flows from financing activities: Repayments under revolving line of credit (10,000 ) — — (10,000 ) Payments on notes payable and long-term debt (30,169 ) (638 ) — (30,807 ) Cost associated with issuance of debt (1,247 ) — — (1,247 ) Intercompany lending 7,983 (12,522 ) 4,539 — Proceeds from employee stock purchases and exercise of stock options 214 — — 214 Net proceeds from issuance of stocks 46,999 — — 46,999 Dividend payment to noncontrolling interest (200 ) — — (200 ) Other financing activities (1,151 ) — — (1,151 ) Net cash provided by (used in) financing activities 12,429 (13,160 ) 4,539 3,808 Effect of change in foreign currency exchange rates on cash, cash equivalents and restricted cash — — 319 319 Net increase (decrease) in cash and cash equivalents (25,622 ) (19 ) 7,076 (18,565 ) Cash, cash equivalents and restricted cash at beginning of period 39,707 66 12,646 52,419 Cash, cash equivalents and restricted cash at end of period $ 14,085 $ 47 $ 19,722 $ 33,854 . The following table is a reconciliation of cash, cash equivalents and restricted cash: December 31, 2018 ION Geophysical Corporation The Guarantors All Other Subsidiaries Total Consolidated (In thousands) Cash and cash equivalents $ 13,782 $ 47 $ 19,722 $ 33,551 Restricted cash included in other long-term assets 303 — — 303 Total cash, cash equivalents, and restricted cash shown in statements of cash flows $ 14,085 $ 47 $ 19,722 $ 33,854 Year Ended December 31, 2017 Statement of Cash Flows ION Geophysical Corporation The Guarantors All Other Subsidiaries Total Consolidated (In thousands) Cash flows from operating activities: Net cash provided by (used in) operating activities $ (22,315 ) $ 73,154 $ (23,227 ) $ 27,612 Cash flows from investing activities: Investment in multi-client data library — (23,710 ) — (23,710 ) Purchase of property, plant, equipment and seismic rental equipment (165 ) (817 ) (81 ) (1,063 ) Net cash used in investing activities (165 ) (24,527 ) (81 ) (24,773 ) Cash flows from financing activities: Payments on notes payable and long-term debt (1,591 ) (3,167 ) (58 ) (4,816 ) Cost associated with issuance of debt (53 ) — — (53 ) Intercompany lending 38,732 (45,609 ) 6,877 — Proceeds from employee stock purchases and exercise of stock options 1,619 — — 1,619 Payments to repurchase bonds — — — — Dividend payment to noncontrolling interest (100 ) — — (100 ) Other financing activities (243 ) — — (243 ) Net cash provided by (used in) financing activities 38,364 (48,776 ) 6,819 (3,593 ) Effect of change in foreign currency exchange rates on cash, cash equivalents and restricted cash — — (260 ) (260 ) Net increase (decrease) in cash and cash equivalents 15,884 (149 ) (16,749 ) (1,014 ) Cash, cash equivalents and restricted cash at beginning of period 23,823 215 29,395 53,433 Cash, cash equivalents and restricted cash at end of period $ 39,707 $ 66 $ 12,646 $ 52,419 The following table is a reconciliation of cash, cash equivalents and restricted cash: December 31, 2017 ION Geophysical Corporation The Guarantors All Other Subsidiaries Total Consolidated (In thousands) Cash and cash equivalents $ 39,344 $ 66 $ 12,646 $ 52,056 Restricted cash included in prepaid expenses and other current assets 60 — — 60 Restricted cash included in other long-term assets 303 — — 303 Total cash, cash equivalents, and restricted cash shown in statements of cash flows $ 39,707 $ 66 $ 12,646 $ 52,419 Year Ended December 31, 2016 Statement of Cash Flows ION Geophysical Corporation The Guarantors All Other Subsidiaries Total Consolidated (In thousands) Cash flows from operating activities: Net cash provided by (used in) operating activities $ (30,732 ) $ 53,107 $ (21,382 ) $ 993 Cash flows from investing activities: Investment in multi-client data library — (14,884 ) — (14,884 ) Purchase of property, plant and equipment (73 ) (313 ) (1,072 ) (1,458 ) Proceeds from sale of a cost-method investment 2,698 — — 2,698 Net cash provided by (used in) investing activities 2,625 (15,197 ) (1,072 ) (13,644 ) Cash flows from financing activities: Payments under revolving line of credit (5,000 ) — — (5,000 ) Borrowings under revolving line of credit 15,000 — — 15,000 Payments on notes payable and long-term debt (17,070 ) (6,316 ) (248 ) (23,634 ) Cost associated with issuance of debt (6,744 ) — — (6,744 ) Repurchase of common stock (964 ) — — (964 ) Intercompany lending 31,867 (34,771 ) 2,904 — Other financing activities (252 ) — — (252 ) Net cash provided by (used in) financing activities 16,837 (41,087 ) 2,656 (21,594 ) Effect of change in foreign currency exchange rates on cash, cash equivalents and restricted cash — — 1,386 1,386 Net decrease in cash and cash equivalents (11,270 ) (3,177 ) (18,412 ) (32,859 ) Cash, cash equivalents and restricted cash at beginning of period 35,093 3,392 47,807 86,292 Cash, cash equivalents and restricted cash at end of period $ 23,823 $ 215 $ 29,395 $ 53,433 The following table is a reconciliation of cash, cash equivalents and restricted cash: December 31, 2016 ION Geophysical Corporation The Guarantors All Other Subsidiaries Total Consolidated (In thousands) Cash and cash equivalents $ 23,042 $ 215 $ 29,395 $ 52,652 Restricted cash included in prepaid expenses and other current assets 260 — — 260 Restricted cash included in other long-term assets 521 — — 521 Total cash, cash equivalents, and restricted cash shown in statements of cash flows $ 23,823 $ 215 $ 29,395 $ 53,433

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Cash and Cash Equivalents and Foreign Currency Gains (Losses) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash and Cash Equivalents [Abstract]
Short-term restricted cash	$ 0.3	$ 0.4
Foreign Currency Gains and Losses
Total foreign currency transaction gains (losses)	$ (0.4)	$ (1.6)	$ (3.3)

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Property, Plant, Equipment and Seismic Rental Equipment Useful Lives (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Impairment charges recognized	$ 36,553	$ 0	$ 0
Machinery and equipment | Minimum
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment useful life	3 years
Machinery and equipment | Maximum
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment useful life	7 years
Buildings | Minimum
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment useful life	5 years
Buildings | Maximum
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment useful life	25 years
Seismic rental equipment | Minimum
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment useful life	3 years
Seismic rental equipment | Maximum
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment useful life	5 years
Leased equipment and other | Minimum
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment useful life	3 years
Leased equipment and other | Maximum
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment useful life	10 years

Summary of Signigicant Accounti

Summary of Signigicant Accounting Policies - Multi-client Data Library Costs and Accumulated Amortization (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Multi-client data library capitalized income	$ 11,900	$ 12,700	$ 6,600
Multi Client Data Creation Cost [Abstract]
Gross costs of multi-client data creation	972,309	939,077
Less accumulated amortization	(776,860)	(727,872)
Less impairments to multi-client data library	(121,905)	(121,905)
Multi-client data library, net	$ 73,544	$ 89,300

Summary of Significant Accoutni

Summary of Significant Accoutning Policies - Equity Method Investment (Details) - INOVA Geophysical - USD ($)	Dec. 31, 2018	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Equity method investment, Accumulated other comprehensive loss		$ 0
Equity method investments	$ 0

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Goodwill and Other Intangible Assets (Details)	12 Months Ended
	Dec. 31, 2018
Goodwill
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Operational forecast period used in fair value inputs	3 years

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Concentration of Foreign Sales Risk (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Geographic Concentration Risk | Sales Revenue, Net | Non-US
Concentration Risk [Line Items]
International sales comprised of total net revenue	75.00%	76.00%	78.00%

Segment and Geographic Inform_3

Segment and Geographic Information - Summary of Segment Information (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018USD ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2018USD ($)segment	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segment									2
Reclassified its previously reported results to reflect segment changes
Net revenues	$ 74,594	$ 47,200	$ 24,743	$ 33,508	$ 57,902	$ 61,095	$ 46,001	$ 32,556	$ 180,045	$ 197,554	$ 172,808
Gross profit (loss):	37,809	16,475	(1,517)	6,853	23,811	30,109	15,618	6,101	$ 59,620	$ 75,639	$ 36,032
Gross margin:									33.00%	38.00%	21.00%
Income (loss) from operations:	(16,661)	(2,452)	(22,519)	(12,640)	(1,151)	9,936	(3,572)	(13,912)	$ (54,272)	$ (8,699)	$ (43,171)
Interest expense, net	(3,203)	(3,022)	(2,911)	(3,836)	(4,045)	(3,959)	(4,241)	(4,464)	(12,972)	(16,709)	(18,485)
Other income (expense), net	$ 180	$ 91	$ 84	$ (791)	$ 209	$ 722	$ 192	$ (5,068)	(436)	(3,945)	1,350
Loss before income taxes									(67,680)	(29,353)	(60,306)
Operating expenses									113,892	84,338	79,203
Impairment of long-lived assets									36,553	0	0
Operations Optimization
Reclassified its previously reported results to reflect segment changes
Impairment of long-lived assets									21,300
Operating segments
Reclassified its previously reported results to reflect segment changes
Gross profit (loss):									$ 65,662	$ 85,272	$ 26,453
Gross margin:									36.00%	43.00%	15.00%
Operating segments | E&P Technology & Services
Reclassified its previously reported results to reflect segment changes
Net revenues									$ 136,520	$ 157,249	$ 92,889
Gross profit (loss):									$ 43,369	$ 65,196	$ 4,708
Gross margin:									32.00%	41.00%	5.00%
Income (loss) from operations:									$ 21,758	$ 42,505	$ (16,446)
Operating segments | E&P Technology & Services | New Venture and Data Library
Reclassified its previously reported results to reflect segment changes
Net revenues									116,780	140,840	67,351
Operating segments | E&P Technology & Services | New Venture
Reclassified its previously reported results to reflect segment changes
Net revenues									69,685	100,824	27,362
Operating segments | E&P Technology & Services | Data Library
Reclassified its previously reported results to reflect segment changes
Net revenues									47,095	40,016	39,989
Operating segments | E&P Technology & Services | Imaging Services
Reclassified its previously reported results to reflect segment changes
Net revenues									19,740	16,409	25,538
Operating segments | Operations Optimization
Reclassified its previously reported results to reflect segment changes
Net revenues									43,525	40,305	43,502
Gross profit (loss):									$ 22,293	$ 20,076	$ 21,745
Gross margin:									51.00%	50.00%	50.00%
Income (loss) from operations:									$ 7,295	$ 8,022	$ 9,652
Operating segments | Operations Optimization | Devices
Reclassified its previously reported results to reflect segment changes
Net revenues									22,396	23,610	26,746
Operating segments | Operations Optimization | Optimization Software & Services
Reclassified its previously reported results to reflect segment changes
Net revenues									21,129	16,695	16,756
Other
Reclassified its previously reported results to reflect segment changes
Net revenues									0	0	36,417
Gross profit (loss):									$ (6,042)	$ (9,633)	$ 9,579
Gross margin:									(3.00%)	(5.00%)	6.00%
Support and other
Reclassified its previously reported results to reflect segment changes
Income (loss) from operations:									$ (83,325)	$ (59,226)	$ (36,377)
Previously Reported
Segment Reporting Information [Line Items]
Number of operating segments | segment									3
Previously Reported | Ocean Bottom Integrated Technologies
Reclassified its previously reported results to reflect segment changes
Impairment of long-lived assets									$ 15,300
Previously Reported | Operating segments | Ocean Bottom Integrated Technologies
Reclassified its previously reported results to reflect segment changes
Income (loss) from operations:									47,600	16,300	1,800
Operating expenses									$ 41,600	$ 6,700	$ 11,300

Segment and Geographic Inform_4

Segment and Geographic Information - Depreciation and Amortization (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Depreciation and amortization (including multi-client data library)	$ 57,751	$ 63,694	$ 55,310
Operating segments | E&P Technology & Services
Segment Reporting Information [Line Items]
Depreciation and amortization (including multi-client data library)	51,673	53,663	44,100
Operating segments | Operations Optimization
Segment Reporting Information [Line Items]
Depreciation and amortization (including multi-client data library)	995	1,349	1,780
Support and other
Segment Reporting Information [Line Items]
Depreciation and amortization (including multi-client data library)	5,083	8,682	9,430
Previously Reported | Operating segments | Ocean Bottom Integrated Technologies
Segment Reporting Information [Line Items]
Depreciation and amortization (including multi-client data library)	$ 4,200	$ 7,000	$ 7,500

Segment and Geographic Inform_5

Segment and Geographic Information - Summary of Total Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Total assets	$ 244,749	$ 301,069
Impairment of long-lived assets	36,553	0	$ 0
North America
Segment Reporting Information [Line Items]
Total assets	86,614	116,598
Latin America
Segment Reporting Information [Line Items]
Total assets	69,418	55,661
Middle East
Segment Reporting Information [Line Items]
Total assets	52,037	70,308
Europe
Segment Reporting Information [Line Items]
Total assets	31,566	51,876
Other
Segment Reporting Information [Line Items]
Total assets	5,114	6,626
Operations Optimization
Segment Reporting Information [Line Items]
Impairment of long-lived assets	21,300
Operating segments | E&P Technology & Services
Segment Reporting Information [Line Items]
Total assets	165,132	156,555
Operating segments | Operations Optimization
Segment Reporting Information [Line Items]
Total assets	51,783	74,361
Support and other
Segment Reporting Information [Line Items]
Total assets	27,834	70,153
Previously Reported | Ocean Bottom Integrated Technologies
Segment Reporting Information [Line Items]
Impairment of long-lived assets	15,300
Previously Reported | Operating segments | Ocean Bottom Integrated Technologies
Segment Reporting Information [Line Items]
Total assets	$ 1,200	$ 20,800

Segment and Geographic Inform_6

Segment and Geographic Information - Fixed Assets Less Accumulated Depreciation by Geographic Area (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Total fixed assets less accumulated deprecation by geographic area	$ 13,041	$ 52,153
Impairment of long-lived assets	36,553	0	$ 0
North America
Segment Reporting Information [Line Items]
Total fixed assets less accumulated deprecation by geographic area	11,663	10,609
Europe
Segment Reporting Information [Line Items]
Total fixed assets less accumulated deprecation by geographic area	1,140	20,725
Latin America
Segment Reporting Information [Line Items]
Total fixed assets less accumulated deprecation by geographic area	143	170
Middle East
Segment Reporting Information [Line Items]
Total fixed assets less accumulated deprecation by geographic area	36	20,543
Other
Segment Reporting Information [Line Items]
Total fixed assets less accumulated deprecation by geographic area	$ 59	$ 106

Segment and Geographic Inform_7

Segment and Geographic Information - Net Revenues by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Summary of net revenues by geographic area
Net revenues	$ 74,594	$ 47,200	$ 24,743	$ 33,508	$ 57,902	$ 61,095	$ 46,001	$ 32,556	$ 180,045	$ 197,554	$ 172,808
Latin America
Summary of net revenues by geographic area
Net revenues									68,871	68,241	24,090
North America
Summary of net revenues by geographic area
Net revenues									44,474	48,120	38,005
Europe
Summary of net revenues by geographic area
Net revenues									31,077	44,930	41,674
Asia Pacific
Summary of net revenues by geographic area
Net revenues									17,817	18,896	16,226
Africa
Summary of net revenues by geographic area
Net revenues									10,837	6,837	41,417
Middle East
Summary of net revenues by geographic area
Net revenues									5,526	2,308	9,467
Commonwealth of Independent States
Summary of net revenues by geographic area
Net revenues									$ 1,443	$ 8,222	$ 1,929

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Narrative (Details)	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Time period of contractual future performance obligations for which value not disclosed (or less)	1 year
Time period of contractual future performance obligations	For these usage-based licenses, revenue is recognized as the performance obligations are performed over the contract term, which is generally two to five years.

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Unbilled Receivables by Service (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Unbilled receivables	$ 44,032	$ 37,304
New Venture
Disaggregation of Revenue [Line Items]
Unbilled receivables	38,430	33,183
Imaging Services
Disaggregation of Revenue [Line Items]
Unbilled receivables	5,075	4,121
Devices
Disaggregation of Revenue [Line Items]
Unbilled receivables	$ 527	$ 0

Revenue from Contracts with C_5

Revenue from Contracts with Customers - Unbilled Receivables (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)
Unbilled Revenues [Roll Forward]
Unbilled receivables at December 31, 2017	$ 37,304
Recognition of unbilled receivables	153,611
Revenues billed to customers	(146,883)
Unbilled receivables at December 31, 2018	$ 44,032

Revenue from Contracts with C_6

Revenue from Contracts with Customers - Deferred Revenue by Service (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Deferred revenue	$ 7,710	$ 8,910
New Venture
Disaggregation of Revenue [Line Items]
Deferred revenue	5,797	6,548
Imaging Services
Disaggregation of Revenue [Line Items]
Deferred revenue	307	676
Devices
Disaggregation of Revenue [Line Items]
Deferred revenue	626	633
Optimization Software & Services
Disaggregation of Revenue [Line Items]
Deferred revenue	$ 980	$ 1,053

Revenue from Contracts with C_7

Revenue from Contracts with Customers - Deferred Revenue (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)
Revenue, Remaining Performance Obligation [Roll Forward]
Deferred revenue at December 31, 2017	$ 8,910
Cash collected in excess of revenue recognized	25,234
Recognition of deferred revenue	(26,434)
Deferred revenue at December 31, 2018	$ 7,710

Recent Accounting Pronounceme_2

Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by operating activities	$ 7,098	$ 27,612	$ 993
Minimum | Accounting Standards Update 2016-02 | Pro Forma
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use asset				$ 50,000
Lease liability				50,000
Maximum | Accounting Standards Update 2016-02 | Pro Forma
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use asset				60,000
Lease liability				$ 60,000
Restatement Adjustment | Accounting Standards Update 2016-18
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by operating activities		$ (400)	$ (600)

Long-term Debt and Lease Obli_3

Long-term Debt and Lease Obligations - Obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Apr. 28, 2016
Obligations
Costs associated with issuances of debt	$ (2,925)	$ (3,983)
Total	121,741	156,744
Current portion of long-term debt and lease obligations	(2,228)	(40,024)
Non-current portion of long-term debt and lease obligations	119,513	116,720
Senior secured notes | Senior secured second-priority lien notes (maturing December 15, 2021)
Obligations
Long-term debt, gross	120,569	120,569
Total			$ 120,600
Senior secured notes | Senior secured third-priority lien notes (redeemed March 26, 2018)
Obligations
Long-term debt, gross	0	28,497
Total			$ 28,500
Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a)
Obligations
Long-term debt, gross	0	10,000
Equipment capital leases
Obligations
Long-term debt, gross	2,938	279
Other debt
Obligations
Long-term debt, gross	$ 1,159	$ 1,382

Long-term Debt and Lease Obli_4

Long-term Debt and Lease Obligations - Narrative (Details)	Aug. 16, 2018USD ($)	Apr. 28, 2016USD ($)	Dec. 31, 2018USD ($)	Aug. 15, 2018USD ($)	Dec. 31, 2017USD ($)	May 31, 2013
Debt Instrument [Line Items]
Aggregate principal amount of debt			$ 121,741,000		$ 156,744,000
Minimum
Debt Instrument [Line Items]
Interest accrues under the capital leases			4.32%
Maximum
Debt Instrument [Line Items]
Interest accrues under the capital leases			8.70%
Line of credit | Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a) | PNC Bank, National Association (PNC)
Debt Instrument [Line Items]
Debt term	4 years
Amount of increase in maximum revolver	$ 10,000,000
Maximum amount of certain indebtedness	50,000,000		$ 50,000,000	$ 40,000,000
Current borrowing capacity			41,900,000
Indebtedness under the Credit Facility			0
Required liquidity maintained five consecutive business days	6,250,000		7,500,000
Required liquidity maintained any business day	5,000,000		$ 6,500,000
Line of credit | Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a) | PNC Bank, National Association (PNC) | Subsidiary Issuer
Debt Instrument [Line Items]
Percentage of obligations secured by stock of Subsidiary Borrowers		100.00%
Line of credit | Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a) | PNC Bank, National Association (PNC) | Minimum
Debt Instrument [Line Items]
Fixed charge coverage ratio			1.1
Line of credit | Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a) | PNC Bank, National Association (PNC) | GX Geoscience Corporation, S. De R.L. De C.V. [Member]
Debt Instrument [Line Items]
Maximum amount of certain indebtedness	$ 5,000,000
Line of credit | Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a) | PNC Bank, National Association (PNC) | ION International Holdings L.P.
Debt Instrument [Line Items]
Percentage of obligations secured by stock of Subsidiary Borrowers		65.00%
Line of credit | Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a) | PNC Bank, National Association (PNC) | Base Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%
Line of credit | Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a) | PNC Bank, National Association (PNC) | Base Rate | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%
Line of credit | Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a) | PNC Bank, National Association (PNC) | LIBOR | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%
Line of credit | Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a) | PNC Bank, National Association (PNC) | LIBOR | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	4.00%
Senior secured notes
Debt Instrument [Line Items]
Stated rate on debt						8.125%
Senior secured notes | Senior secured third-priority lien notes (redeemed March 26, 2018)
Debt Instrument [Line Items]
Aggregate principal amount of debt		$ 28,500,000
Senior secured notes | Senior secured second-priority lien notes (maturing December 15, 2021)
Debt Instrument [Line Items]
Stated rate on debt		9.125%			9.125%
Aggregate principal amount of debt		$ 120,600,000
E&P Technology & Services | Data Library | Line of credit | Revolving credit facility (amended August 16, 2018, maturing August 16, 2023) (a)
Debt Instrument [Line Items]
Maximum amount of certain indebtedness	$ 28,500,000			$ 15,000,000

Long-term Debt and Lease Obli_5

Long-term Debt and Lease Obligations - Redemption Percentages for Future Periods (Details) - Senior secured notes - Senior secured second-priority lien notes (maturing December 15, 2021) - Forecast	Dec. 15, 2019
2019
Debt Instrument, Redemption [Line Items]
Notes redemption percentages	105.50%
2020
Debt Instrument, Redemption [Line Items]
Notes redemption percentages	103.50%
2021 and thereafter
Debt Instrument, Redemption [Line Items]
Notes redemption percentages	100.00%

Long-term Debt and Lease Obli_6

Long-term Debt and Lease Obligations - Equipment Capital Leases (Details) $ in Thousands	Dec. 31, 2018USD ($)
Equipment Capital Leases
2019	$ 2,228
2020	1,135
2021	121,303
Total	124,666
Short-Term and Long-Term Debt
Equipment Capital Leases
2019	0
2020	0
2021	120,569
Total	120,569
Capital Lease Obligations
Equipment Capital Leases
2019	1,069
2020	1,135
2021	734
Total	2,938
Other Financing
Equipment Capital Leases
2019	1,159
2020	0
2021	0
Total	$ 1,159

Net Income (Loss) per Common _2

Net Income (Loss) per Common Share (Details) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Number of shares issuable under anti-dilutive options (in shares)	785,890	890,341	847,635

Income Taxes - Sources of Incom

Income Taxes - Sources of Income (Loss) Before Taxes and Components of Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Sources of income (loss) before income taxes
Domestic									$ (59,212)	$ (12,487)	$ (41,246)
Foreign									(8,468)	(16,866)	(19,060)
Loss before income taxes									(67,680)	(29,353)	(60,306)
Current:
Federal									0	(166)	0
State and local									65	116	28
Foreign									8,905	5,494	5,574
Deferred:
Federal									(346)	(1,263)	0
Foreign									(5,906)	(4,157)	(1,181)
Total income tax expense	$ (587)	$ 2,079	$ 154	$ 1,072	$ (3,646)	$ 1,686	$ 2,402	$ (418)	$ 2,718	$ 24	$ 4,421

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Expected Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of the expected income tax expense on income (loss) before income taxes using the statutory federal income tax
Expected income tax expense at 21% for 2018 and 35% for 2017 and 2016									$ (14,213)	$ (10,274)	$ (21,107)
Foreign tax rate differential									74	(2,914)	5,932
Foreign tax differences									4,703	(5,610)	(4,828)
Global intangible low tax income inclusion									3,443	0	0
State and local taxes									65	116	28
Nondeductible expenses									1,604	4,308	(259)
Change in U.S. tax rate									0	77,410	0
Expired capital loss									0	1,114	1,321
Valuation allowance:
Valuation allowance on expiring capital losses									0	(1,114)	(1,321)
Valuation allowance on operations									7,042	(63,012)	24,655
Total income tax expense	$ (587)	$ 2,079	$ 154	$ 1,072	$ (3,646)	$ 1,686	$ 2,402	$ (418)	$ 2,718	$ 24	$ 4,421

Income Taxes - Tax Effects of C

Income Taxes - Tax Effects of Cumulative Temporary Differences (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred income tax assets:
Accrued expenses	$ 1,126	$ 1,976
Allowance accounts	6,415	2,960
Net operating loss carryforward	96,854	87,705
Equity method investment	35,292	35,292
Original issue discount	8,073	9,624
Interest limitation	5,845	0
Basis in identified intangibles	4,146	9,408
Tax credit carryforwards	5,345	6,929
Contingency accrual	0	788
Other	4,600	4,035
Total deferred income tax asset	167,696	158,717
Valuation allowance	(160,505)	(153,463)
Net deferred income tax asset	7,191	5,254
Deferred income tax liabilities:
Unbilled receivables	0	(3,501)
Total deferred income tax asset, net	$ 7,191	$ 1,753

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Loss Carryforwards [Line Items]
Unrecognized tax benefits	$ 447	$ 447	$ 1,299	$ 1,250
Outside book-over-tax basis difference in its foreign subsidiaries	85,000
United States Tax Authority
Operating Loss Carryforwards [Line Items]
Net operating loss carry-forwards	274,400
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Net operating loss carry-forwards	$ 153,100

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 447	$ 1,299	$ 1,250
Increases in unrecognized tax benefits – current year positions	0	59	49
Decreases in unrecognized tax benefits – prior year position	0	(911)	0
Ending balance	$ 447	$ 447	$ 1,299

Legal Matters (Details)

Legal Matters (Details) - WesternGeco	Mar. 14, 2017USD ($)	Nov. 25, 2016USD ($)	Dec. 31, 2018USD ($)Patent	Dec. 31, 2014USD ($)	Dec. 31, 2015USD ($)
Loss Contingencies [Line Items]
Number of claims invalidated | Patent			4
Number of claims | Patent			6
Settled Litigation
Loss Contingencies [Line Items]
Accrual for loss contingency related to legal proceedings			$ 0
Total damages awarded	$ 5,000,000			$ 9,400,000
Prejudgment interest expense accrued				10,900,000
Damages paid		$ 20,800,000
Damages sought	$ 43,600,000
Settled Litigation | Lost Royalties
Loss Contingencies [Line Items]
Total damages awarded				12,500,000
Settled Litigation | Lost Profits
Loss Contingencies [Line Items]
Accrual for loss contingency related to legal proceedings				123,800,000	$ 22,000,000
Total damages awarded				$ 93,400,000

Other Income (Expense) (Details

Other Income (Expense) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Income and Expenses [Abstract]
(Accrual for) reduction of loss contingency related to legal proceedings (Footnote 8)									$ 0	$ (5,000)	$ 1,168
Recovery of INOVA bad debts									0	844	3,983
Loss on bond exchange									0	0	(2,182)
Other income (expense)									(436)	211	(1,619)
Total other income (expense), net	$ 180	$ 91	$ 84	$ (791)	$ 209	$ 722	$ 192	$ (5,068)	$ (436)	$ (3,945)	$ 1,350

Details of Selected Balance S_3

Details of Selected Balance Sheet Accounts - Accounts Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accounts receivable, principally trade	$ 26,558	$ 20,050
Less allowance for doubtful accounts	(430)	(572)
Accounts receivable, net	$ 26,128	$ 19,478

Details of Selected Balance S_4

Details of Selected Balance Sheet Accounts - Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials and purchased subassemblies	$ 20,011	$ 20,448
Work-in-process	1,032	1,146
Finished goods	8,111	7,953
Less reserve for excess and obsolete inventories	(15,024)	(15,039)
Inventories, net	$ 14,130	$ 14,508

Details of Selected Balance S_5

Details of Selected Balance Sheet Accounts - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment	$ 183,228	$ 195,987
Less accumulated depreciation	(133,634)	(143,834)
Less impairment of long-lived assets	(36,553)	0	$ 0
Property, plant, equipment and seismic rental equipment, net	13,041	52,153
Depreciation and amortization under capital leases	7,600	15,200	$ 20,300
Buildings
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment	15,707	15,822
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment	132,135	145,654
Seismic rental equipment
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment	1,423	1,677
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment	3,859	3,869
Other
Property, Plant and Equipment [Line Items]
Property, plant, equipment and seismic rental equipment	$ 30,104	$ 28,965

Details of Selected Balance S_6

Details of Selected Balance Sheet Accounts - Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Compensation, including compensation-related taxes and commissions	$ 14,502	$ 19,809
Accrued multi-client data library acquisition costs	3,746	5,104
Income tax payable	7,577	1,868
Accrual for loss contingency related to legal proceedings (Footnote 8)	0	3,750
Other	5,586	8,166
Total accrued expenses	$ 31,411	$ 38,697

Details of Selected Balance S_7

Details of Selected Balance Sheet Accounts - Other Long-term Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Deferred lease liabilities	$ 11,465	$ 12,811
Other	429	1,115
Total	$ 11,894	$ 13,926

Goodwill (Details)

Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Changes in the carrying amount of goodwill
Goodwill, balance beginning	$ 24,089	$ 22,208
Impact of foreign currency translation adjustments	(1,174)	1,881
Goodwill, balance ending	22,915	24,089
E&P Technology & Services
Changes in the carrying amount of goodwill
Goodwill, balance beginning	2,943	2,943
Impact of foreign currency translation adjustments	0	0
Goodwill, balance ending	2,943	2,943
Optimization Software & Services
Changes in the carrying amount of goodwill
Goodwill, balance beginning	21,146	19,265
Impact of foreign currency translation adjustments	(1,174)	1,881
Goodwill, balance ending	$ 19,972	$ 21,146

Stockholder's Equity and Stoc_3

Stockholder's Equity and Stock-based Compensation - Narrative (Details)	Dec. 01, 2018$ / sharesshares	May 30, 2018$ / sharesshares	Feb. 21, 2018$ / sharesshares	Dec. 14, 2017$ / sharesshares	Mar. 01, 2016individual$ / sharesshares	Feb. 04, 2016	Mar. 01, 2015individual$ / sharesshares	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2018USD ($)$ / sharesshares	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016USD ($)$ / shares	Dec. 31, 2015$ / shares	Nov. 30, 2018shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional warrants purchased (in shares) | shares			1,820,000
Net proceeds from issuance of stocks | $										$ 46,999,000	$ 0	$ 0
Extinguishment of debt | $								$ 28,500,000
Warrants exercise price (usd per share)			$ 33.60
Total intrinsic value of options exercised | $										1,400,000	100,000	100,000
Cash received from option exercises | $										$ 200,000	$ 100,000	$ 0
Weighted average grant date fair value for stock option awards (usd per share)										$ 15.23	$ 8.10	$ 2.04
Term of common stock used in determining market-based implied volatility										6 months
Stock available for issuance (in shares) | shares														1,700,000
Outstanding, maximum (usd per share)										$ 151.35	245.85	245.85	$ 245.85
Outstanding, minimum (usd per share)										$ 3.10	$ 3.10	$ 3.10	$ 34.20
Reverse stock split ratio of one share						0.066667
Exercise of stock options (in shares) | shares										70,086	15,000
Stock-based compensation expense | $										$ 3,337,000	$ 2,552,000	$ 3,267,000
2013 LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock available for issuance (in shares) | shares														1,200,000
Equity Investment Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock purchased to restricted stock issued, ratio									0.2
Equity Investment Program | Executive officers and other key employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, award vesting period										90 days
Number of common stock shares sold (in shares) | shares				219,346
Equity Investment Program | Private placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price per share of common stock share sold (usd per share)				$ 13.05
Number of common stock shares sold (in shares) | shares				120,567
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, award vesting period										4 years
Stock options, term in years										10 years
Restricted stock and restricted stock unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Public equity offering (in shares) | shares	900,002
Stock options, award vesting period										3 years
Weighted average price limit in vesting period (usd per share)		$ 24.75
Intrinsic value of restricted stock and restricted stock unit awards | $									$ 4,000,000	$ 5,400,000	$ 4,000,000	$ 1,700,000
Weighted average grant date fair value for restricted stock and restricted stock unit awards (usd per share)										$ 10.60	$ 11.36	$ 3.81
Total fair value of shares vested | $										$ 3,800,000	$ 600,000	$ 200,000
Shares vested (in shares) | shares		43,865								151,852
Restricted stock and restricted stock unit | First one-third of awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value for stock option awards (usd per share)	$ 7.19
Weighted average price limit in vesting period (usd per share)	17.50
Restricted stock and restricted stock unit | Second one-third of awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value for stock option awards (usd per share)	6.51
Weighted average price limit in vesting period (usd per share)	22.50
Restricted stock and restricted stock unit | Final one-third of awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value for stock option awards (usd per share)	5.89
Weighted average price limit in vesting period (usd per share)	$ 27.50
Stock appreciation rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Public equity offering (in shares) | shares	960,009
Stock options, award vesting period					4 years		4 years
Stock options, term in years										10 years
Weighted average grant date fair value for stock option awards (usd per share)										$ 8.85		$ 17.55
Exercise price of awards issued during period	$ 8.85				$ 3.1		$ 34.20
Maximum value of SARs (in dollars per share)										18.65		19.40
Outstanding, maximum (usd per share)										27.50		22.50
Outstanding, minimum (usd per share)										$ 8.85		$ 3.10
Number of awards issued during period | shares					1,210,000		207,207
Number of individuals that received SARs | individual					15		16
Percentage of fair market value of shares for calculation of exercise price SAR										100.00%
Percentage of shares allowed to be exercised annually, if vested					33.33%		33.33%
Exercise of stock options (in shares) | shares										34,999	713,330
Number of days volume-weighted average price of stock measured for vesting							20 days
Stock-based compensation expense | $										$ 800,000	$ 6,600,000	$ 500,000
Stock appreciation rights (SARs) | Equity Investment Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise of stock options (in shares) | shares										663,330
Participants gain on exercises of awards (usd per share)										$ 9.95
Stock appreciation rights (SARs) | First one-third of awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage					33.33%		33.33%
Percentage that weighted average price of common stock must be greater than exercise price of SARs					120.00%		120.00%
Stock appreciation rights (SARs) | Second one-third of awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage					33.33%		33.33%
Percentage that weighted average price of common stock must be greater than exercise price of SARs					125.00%		125.00%
Stock appreciation rights (SARs) | Final one-third of awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage					33.33%		33.33%
Percentage that weighted average price of common stock must be greater than exercise price of SARs					130.00%		130.00%
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Public equity offering (in shares) | shares			1,820,000							1,820,000
Price per share of common stock share sold (usd per share)			$ 27.5
Exercise of stock options (in shares) | shares										70,086	15,000

Stockholder's Equity and Stoc_4

Stockholder's Equity and Stock-based Compensation - Transactions Under Stock Option Plans Summary (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Option Price per Share
Outstanding, minimum (usd per share)	$ 3.10	$ 3.10	$ 3.10	$ 34.20
Outstanding, maximum (usd per share)	151.35	245.85	245.85	$ 245.85
Granted, minimum (usd per share)	24.50	13.15	3.10
Granted, maximum (usd per share)	24.50	13.15	3.10
Exercised, minimum (usd per share)	3.10	3.10
Exercised, maximum (usd per share)	3.10	3.10
Cancelled/forfeited, minimum (usd per share)	3.10	3.10	3.10
Cancelled/forfeited, maximum (usd per share)	$ 245.85	$ 245.85	$ 245.85
Outstanding
Beginning balance (in shares)	890,341	847,635	560,797
Granted (in shares)	10,000	156,000	415,000
Exercised (in shares)	(70,086)	(15,000)
Cancelled/forfeited (in shares)	(44,365)	(98,294)	(128,162)
Ending balance (in shares)	785,890	890,341	847,635	560,797
Vested
Vested, beginning balance (in shares)	435,278	348,353	384,305
Vested (in shares)	153,944	149,537	67,480
Exercised (in shares)	(70,086)	(15,000)
Cancelled/forfeited (in shares)	(44,231)	(47,612)	(103,432)
Vested, ending balance (in shares)	474,905	435,278	348,353	384,305
Available for Grant
Beginning balance (in shares)	488,403	599,720	97,003
Increase in shares authorized (in shares)	1,200,000		1,150,940
Granted (in shares)	10,000	156,000	415,000
Cancelled/forfeited (in shares)	2,568	82,118	18,895
Restricted stock granted out of option plans (in shares)	(996,775)	(59,500)	(259,300)
Restricted stock forfeited or cancelled for employee minimum income taxes and returned to the plans (in shares)	48,524	22,065	7,182
Ending balance (in shares)	732,720	488,403	599,720	97,003

Stockholder's Equity and Stoc_5

Stockholder's Equity and Stock-based Compensation - Stock Options Outstanding by Price Range (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Summary of stock options outstanding
Option Price per Share, minimum (usd per share)	$ 3.10	$ 3.10	$ 3.10	$ 34.20
Option Price per Share, maximum (usd per share)	$ 151.35	$ 245.85	$ 245.85	$ 245.85
Outstanding (in shares)	785,890
Weighted Average Exercise Price of Outstanding Options (usd per share)	$ 35.33
Weighted Average Remaining Contract Life	5 years 4 months 24 days
Vested (in shares)	474,905
Weighted Average Exercise Price of Vested Options (usd per share)	$ 52.76
$3.10 - $57.90
Summary of stock options outstanding
Option Price per Share, minimum (usd per share)	3.10
Option Price per Share, maximum (usd per share)	$ 57.90
Outstanding (in shares)	558,997
Weighted Average Exercise Price of Outstanding Options (usd per share)	$ 15.64
Weighted Average Remaining Contract Life	7 years 2 months 12 days
Vested (in shares)	248,012
Weighted Average Exercise Price of Vested Options (usd per share)	$ 24.32
$61.05 - $71.85
Summary of stock options outstanding
Option Price per Share, minimum (usd per share)	61.05
Option Price per Share, maximum (usd per share)	$ 71.85
Outstanding (in shares)	75,231
Weighted Average Exercise Price of Outstanding Options (usd per share)	$ 62.17
Weighted Average Remaining Contract Life	4 years 8 months 12 days
Vested (in shares)	75,231
Weighted Average Exercise Price of Vested Options (usd per share)	$ 62.17
$81.60 - $99.60
Summary of stock options outstanding
Option Price per Share, minimum (usd per share)	81.60
Option Price per Share, maximum (usd per share)	$ 99.60
Outstanding (in shares)	108,610
Weighted Average Exercise Price of Outstanding Options (usd per share)	$ 88.94
Weighted Average Remaining Contract Life	3 years 7 months 2 days
Vested (in shares)	108,610
Weighted Average Exercise Price of Vested Options (usd per share)	$ 88.94
$106.05 - $151.35
Summary of stock options outstanding
Option Price per Share, minimum (usd per share)	106.05
Option Price per Share, maximum (usd per share)	$ 151.35
Outstanding (in shares)	43,052
Weighted Average Exercise Price of Outstanding Options (usd per share)	$ 108.84
Weighted Average Remaining Contract Life	2 years 3 months 18 days
Vested (in shares)	43,052
Weighted Average Exercise Price of Vested Options (usd per share)	$ 108.84

Stockholder's Equity and Stoc_6

Stockholder's Equity and Stock-based Compensation - Stock Options Outstanding Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Number of Shares
Beginning balance (in shares)	890,341	847,635	560,797
Options granted (in shares)	10,000
Options exercised (in shares)	(70,086)	(15,000)
Options cancelled (in shares)	(134)
Options forfeited (in shares)	(44,231)
Ending balance (in shares)	785,890	890,341	847,635
Options exercisable and vested (in shares)	474,905
Weighted Average Exercise Price
Beginning balance (usd per share)	$ 36.17
Options granted (usd per share)	24.50
Options exercised (usd per share)	3.10
Options cancelled (usd per share)	61.05
Options forfeited (usd per share)	100.85
Ending balance (usd per share)	35.33	$ 36.17
Options exercisable and vested (usd per share)	52.76
Additional Disclosures
Weighted average grant date fair value for stock option awards (usd per share)	$ 15.23	$ 8.10	$ 2.04
Weighted average remaining contractual life, outstanding	5 years 4 months 24 days	6 years 4 months 24 days
Weighted average remaining contractual life, Options exercisable and vested	5 years
Aggregate intrinsic value, outstanding	$ 572	$ 6,774
Aggregate intrinsic value, Options exercisable and vested	$ 213

Stockholder's Equity and Stoc_7

Stockholder's Equity and Stock-based Compensation - Valuation Assumptions (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rates	2.78%	2.14%	1.30%
Expected lives (in years)	5 years	5 years	5 years 6 months
Expected dividend yield	0.00%	0.00%	0.00%
Expected volatility	73.67%	74.41%	78.76%
Stock appreciation rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rates	3.00%
Expected lives (in years)	5 years 3 months 22 days
Expected dividend yield	0.00%
Expected volatility	82.90%

Stockholder's Equity and Stoc_8

Stockholder's Equity and Stock-based Compensation - Restricted Stock and Restricted Stock Unit Plans (Details) - Restricted stock and restricted stock unit - shares	May 30, 2018	Dec. 31, 2018
Status of the Company's restricted stock and restricted stock unit awards
Total nonvested, Beginning balance (in shares)		201,702
Granted (in shares)		996,775
Vested (in shares)	(43,865)	(151,852)
Forfeited (in shares)		(2,500)
Total nonvested, Ending balance (in shares)		1,044,125

Stockholder's Equity and Stoc_9

Stockholder's Equity and Stock-based Compensation - Stock Appreciation Rights (SARs) Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Number of Shares
Beginning balance (in shares)	890,341	847,635	560,797
SARs granted (in shares)	10,000
Exercised (in shares)	(70,086)	(15,000)
SARs cancelled (in shares)	(44,231)	(47,612)	(103,432)
SARs forfeited (in shares)	(44,231)
Ending balance (in shares)	785,890	890,341	847,635
Weighted Average Exercise Price
Beginning balance (usd per share)	$ 36.17
Ending balance (usd per share)	35.33	$ 36.17
SARs granted (usd per share)	$ 15.23	$ 8.10	$ 2.04
Weighted average remaining contractual life, outstanding	5 years 4 months 24 days	6 years 4 months 24 days
Aggregate intrinsic value, outstanding	$ 572	$ 6,774
Stock appreciation rights (SARs)
Number of Shares
Beginning balance (in shares)	565,864	1,416,133	216,532
SARs granted (in shares)	960,009		1,210,000
Exercised (in shares)	(34,999)	(713,330)
SARs cancelled (in shares)		(136,939)	(10,399)
SARs forfeited (in shares)	(9,333)
Ending balance (in shares)	1,481,541	565,864	1,416,133
Weighted Average Exercise Price
Beginning balance (usd per share)	$ 13.49	$ 7.70	$ 34.67
SARs granted (usd per share)	8.85		3.10
SARs exercised (usd per share)	3.10	3.10
SARs cancelled (usd per share)		7.70	34.20
SARs forfeited (usd per share)	45
Ending balance (usd per share)	10.53	$ 13.49	7.70
SARs granted (usd per share)	$ 8.85		$ 17.55
Weighted average remaining contractual life, outstanding	8 years 1 month 6 days
Aggregate intrinsic value, outstanding	$ 718
Exercisable and Vested
Number of shares (in shares)	0
Weighted average exercise price (usd per share)	$ 0

Stockholder's Equity and Sto_10

Stockholder's Equity and Stock-based Compensation - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 3,337	$ 2,552	$ 3,267
Tax benefit related thereto	(698)	(862)	(1,168)
Stock-based compensation expense, net of tax	2,639	1,690	2,099
Stock appreciation rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	822	6,611	547
Tax benefit related thereto	(173)	(2,314)	(191)
Stock-based compensation expense, net of tax	$ 649	$ 4,297	$ 356

Supplemental Cash Flow Inform_3

Supplemental Cash Flow Information and Non-Cash Activity (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash paid during the period for:
Interest		$ 5,731	$ 14,181	$ 15,691
Income taxes		3,260	7,030	4,474
Non-cash items from investing and financing activities:
Purchase of computer equipment financed through capital leases		3,297	0	0
Leasehold improvement paid by landlord		0	0	955
Issuance of stock in bond exchange		0	0	10,741
Investment in multi-client data library financed through trade payables		4,956	9,059	0
Segment Reporting Information [Line Items]
Transfer of inventory to property, plant and equipment		$ 0	$ 0	$ 17,662
Ocean Bottom Integrated Technologies
Segment Reporting Information [Line Items]
Transfer of inventory to property, plant and equipment	$ 17,700

Operating Leases - Narrative (D

Operating Leases - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Leases, Operating [Abstract]
Operating leases, rent expense	$ 10.1	$ 11.4	$ 11.3

Operating Leases - Summary of f

Operating Leases - Summary of future rental commitments (Details) $ in Thousands	Dec. 31, 2018USD ($)
Future rental commitments over the next five years under non-cancelable operating leases
2019	$ 13,248
2020	12,857
2021	11,075
2022	10,821
2023	9,205
Total	$ 57,206

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Carrying value of long-term debt and lease obligations	$ 124.7	$ 160.7
Fair value of long-term debt	$ 120.7	$ 158.2

Benefit Plans (Details)

Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Retirement Benefits [Abstract]
Maximum percentage of employee contributions	60.00%
Percentage of contribution made to defined benefit plan	50.00%
Component percent of first compensation contributed to defined benefit plan	6.00%
Company contributions to benefit plans	$ 0.9	$ 0.8	$ 0.8

Selected Quarterly Informatio_3

Selected Quarterly Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Net revenues	$ 74,594	$ 47,200	$ 24,743	$ 33,508	$ 57,902	$ 61,095	$ 46,001	$ 32,556	$ 180,045	$ 197,554	$ 172,808
Gross profit	37,809	16,475	(1,517)	6,853	23,811	30,109	15,618	6,101	59,620	75,639	36,032
Loss from operations	(16,661)	(2,452)	(22,519)	(12,640)	(1,151)	9,936	(3,572)	(13,912)	(54,272)	(8,699)	(43,171)
Interest expense, net	(3,203)	(3,022)	(2,911)	(3,836)	(4,045)	(3,959)	(4,241)	(4,464)	(12,972)	(16,709)	(18,485)
Other income (expense), net	180	91	84	(791)	209	722	192	(5,068)	(436)	(3,945)	1,350
Income tax expense	(587)	2,079	154	1,072	(3,646)	1,686	2,402	(418)	2,718	24	4,421
Net income attributable to noncontrolling interests	(246)	(74)	(366)	(87)	(53)	(78)	(418)	(316)	(773)	(865)	(421)
Net loss attributable to ION	$ (19,343)	$ (7,536)	$ (25,866)	$ (18,426)	$ (1,394)	$ 4,935	$ (10,441)	$ (23,342)	$ (71,171)	$ (30,242)	$ (65,148)
Net loss per share:
Basic (usd per share)	$ (1.38)	$ (0.54)	$ (1.86)	$ (1.44)	$ (0.12)	$ 0.42	$ (0.88)	$ (1.98)	$ (5.20)	$ (2.55)	$ (5.71)
Diluted (usd per share)	$ (1.38)	$ (0.54)	$ (1.86)	$ (1.44)	$ (0.12)	$ 0.41	$ (0.88)	$ (1.98)	$ (5.20)	$ (2.55)	$ (5.71)
Service
Disaggregation of Revenue [Line Items]
Net revenues	$ 61,095	$ 37,105	$ 15,752	$ 25,086	$ 48,513	$ 52,615	$ 34,454	$ 23,828	$ 139,038	$ 159,410	$ 130,640
Product
Disaggregation of Revenue [Line Items]
Net revenues	$ 13,499	$ 10,095	$ 8,991	$ 8,422	$ 9,389	$ 8,480	$ 11,547	$ 8,728	$ 41,007	$ 38,144	$ 42,168

Certain Relationships and Rel_2

Certain Relationships and Related Party Transactions (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)ft²	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Majority Shareholder
Related Party Transaction [Line Items]
Related party transaction, revenues from transactions with related party	$ 4.9	$ 4.4	$ 3.6
Receivables due from BGP	$ 1.6	0.6
Company's outstanding common stock owned by related parties	10.60%
Board of Directors Chairman
Related Party Transaction [Line Items]
Company's outstanding common stock owned by related parties	8.80%
Payments for continued services agreement (less than)			$ 0.1
Area of office space subleased (sqft) | ft²	4,100
Board of Directors Chairman | Manufacturing facility
Related Party Transaction [Line Items]
Payments for continued services agreement (less than)	$ 0.4	$ 0.2

Condensed Consolidating Finan_3

Condensed Consolidating Financial Information - Condensed Consolidating Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 33,551	$ 52,056	$ 52,652
Total cash, cash equivalents, and restricted cash shown in consolidated statements of cash flows	33,854	52,419	53,433	$ 86,292
Accounts receivable, net	26,128	19,478
Unbilled receivables	44,032	37,304
Inventories, net	14,130	14,508
Prepaid expenses and other current assets	7,782	7,643
Total current assets	125,623	130,989
Deferred income tax asset	7,191	1,753
Property, plant, equipment and seismic rental equipment, net	13,041	52,153
Multi-client data library, net	73,544	89,300
Investment in subsidiaries	0	0
Goodwill	22,915	24,089	22,208
Intercompany receivables	0	0
Other assets	2,435	2,785
Total assets	244,749	301,069
Deferred income tax asset
Current maturities of long-term debt	2,228	40,024
Accounts payable	34,913	24,951
Accrued expenses	31,411	38,697
Accrued multi-client data library royalties	29,256	27,035
Deferred revenue	7,710	8,910
Total current liabilities	105,518	139,617
Long-term debt, net of current maturities	119,513	116,720
Intercompany payables	0	0
Other long-term liabilities	11,894	13,926
Total liabilities	236,925	270,263
Equity:
Common stock	140	120
Additional paid-in capital	952,626	903,247
Accumulated earnings (deficit)	(926,092)	(854,921)
Accumulated other comprehensive income (loss)	(20,442)	(18,879)
Due from ION Geophysical Corporation	0	0
Total stockholders’ equity	6,232	29,567
Noncontrolling interests	1,592	1,239
Total equity	7,824	30,806	53,398	112,040	[1]
Total liabilities and equity	244,749	301,069
Reportable Legal Entities | ION Geophysical Corporation
Current assets:
Cash and cash equivalents	13,782	39,344	23,042
Total cash, cash equivalents, and restricted cash shown in consolidated statements of cash flows	14,085	39,707	23,823	35,093
Accounts receivable, net	8	50
Unbilled receivables	0	0
Inventories, net	0	0
Prepaid expenses and other current assets	3,891	2,427
Total current assets	17,681	41,821
Deferred income tax asset	805	1,264
Property, plant, equipment and seismic rental equipment, net	489	511
Multi-client data library, net	0	0
Investment in subsidiaries	836,002	693,679
Goodwill	0	0
Intercompany receivables	0	0
Other assets	1,723	686
Total assets	856,700	737,961
Deferred income tax asset
Current maturities of long-term debt	1,159	39,774
Accounts payable	2,407	1,774
Accrued expenses	7,011	12,284
Accrued multi-client data library royalties	0	0
Deferred revenue	0	0
Total current liabilities	10,577	53,832
Long-term debt, net of current maturities	117,644	116,691
Intercompany payables	721,817	537,417
Other long-term liabilities	430	454
Total liabilities	850,468	708,394
Equity:
Common stock	140	120
Additional paid-in capital	952,626	903,247
Accumulated earnings (deficit)	(926,092)	(854,921)
Accumulated other comprehensive income (loss)	(20,442)	(18,879)
Due from ION Geophysical Corporation	0	0
Total stockholders’ equity	6,232	29,567
Noncontrolling interests	0	0
Total equity	6,232	29,567
Total liabilities and equity	856,700	737,961
Reportable Legal Entities | The Guarantors
Current assets:
Cash and cash equivalents	47	66	215
Total cash, cash equivalents, and restricted cash shown in consolidated statements of cash flows	47	66	215	3,392
Accounts receivable, net	17,349	12,496
Unbilled receivables	12,697	34,484
Inventories, net	8,721	8,686
Prepaid expenses and other current assets	1,325	4,530
Total current assets	40,139	60,262
Deferred income tax asset	6,261	336
Property, plant, equipment and seismic rental equipment, net	8,922	7,170
Multi-client data library, net	70,380	81,442
Investment in subsidiaries	247,359	321,934
Goodwill	0	0
Intercompany receivables	305,623	162,017
Other assets	643	1,811
Total assets	679,327	634,972
Deferred income tax asset
Current maturities of long-term debt	1,069	250
Accounts payable	29,602	20,982
Accrued expenses	10,036	16,957
Accrued multi-client data library royalties	29,040	26,824
Deferred revenue	6,515	7,231
Total current liabilities	76,262	72,244
Long-term debt, net of current maturities	1,869	29
Intercompany payables	0	0
Other long-term liabilities	5,698	6,084
Total liabilities	83,829	78,357
Equity:
Common stock	290,460	290,460
Additional paid-in capital	180,700	180,701
Accumulated earnings (deficit)	390,691	317,324
Accumulated other comprehensive income (loss)	4,324	4,372
Due from ION Geophysical Corporation	(270,677)	(236,242)
Total stockholders’ equity	595,498	556,615
Noncontrolling interests	0	0
Total equity	595,498	556,615
Total liabilities and equity	679,327	634,972
Reportable Legal Entities | All Other Subsidiaries
Current assets:
Cash and cash equivalents	19,722	12,646	29,395
Total cash, cash equivalents, and restricted cash shown in consolidated statements of cash flows	19,722	12,646	$ 29,395	$ 47,807
Accounts receivable, net	8,771	6,932
Unbilled receivables	31,335	2,820
Inventories, net	5,409	5,822
Prepaid expenses and other current assets	2,566	686
Total current assets	67,803	28,906
Deferred income tax asset	125	153
Property, plant, equipment and seismic rental equipment, net	3,630	44,472
Multi-client data library, net	3,164	7,858
Investment in subsidiaries	0	0
Goodwill	22,915	24,089
Intercompany receivables	66,021	60,394
Other assets	69	288
Total assets	163,727	166,160
Deferred income tax asset
Current maturities of long-term debt	0	0
Accounts payable	2,904	2,195
Accrued expenses	14,364	9,456
Accrued multi-client data library royalties	216	211
Deferred revenue	1,195	1,679
Total current liabilities	18,679	13,541
Long-term debt, net of current maturities	0	0
Intercompany payables	0	0
Other long-term liabilities	5,766	7,388
Total liabilities	24,445	20,929
Equity:
Common stock	47,776	49,394
Additional paid-in capital	203,908	202,290
Accumulated earnings (deficit)	(12,475)	(9,247)
Accumulated other comprehensive income (loss)	(22,023)	(19,681)
Due from ION Geophysical Corporation	(79,496)	(78,764)
Total stockholders’ equity	137,690	143,992
Noncontrolling interests	1,592	1,239
Total equity	139,282	145,231
Total liabilities and equity	163,727	166,160
Consolidating Adjustments
Current assets:
Cash and cash equivalents		0
Total cash, cash equivalents, and restricted cash shown in consolidated statements of cash flows	0
Accounts receivable, net	0	0
Unbilled receivables	0	0
Inventories, net	0	0
Prepaid expenses and other current assets	0	0
Total current assets	0	0
Deferred income tax asset	0	0
Property, plant, equipment and seismic rental equipment, net	0	0
Multi-client data library, net	0	0
Investment in subsidiaries	(1,083,361)	(1,015,613)
Goodwill	0	0
Intercompany receivables	(371,644)	(222,411)
Other assets	0	0
Total assets	(1,455,005)	(1,238,024)
Deferred income tax asset
Current maturities of long-term debt	0	0
Accounts payable	0	0
Accrued expenses	0	0
Accrued multi-client data library royalties	0	0
Deferred revenue	0	0
Total current liabilities	0	0
Long-term debt, net of current maturities	0	0
Intercompany payables	(721,817)	(537,417)
Other long-term liabilities	0	0
Total liabilities	(721,817)	(537,417)
Equity:
Common stock	(338,236)	(339,854)
Additional paid-in capital	(384,608)	(382,991)
Accumulated earnings (deficit)	(378,216)	(308,077)
Accumulated other comprehensive income (loss)	17,699	15,309
Due from ION Geophysical Corporation	350,173	315,006
Total stockholders’ equity	(733,188)	(700,607)
Noncontrolling interests	0	0
Total equity	(733,188)	(700,607)
Total liabilities and equity	$ (1,455,005)	$ (1,238,024)
[1]	The figures for January 1, 2016, set forth in the tables above have been retroactively adjusted to reflect the one-for-fifteen reverse stock split completed on February 4, 2016.

Condensed Consolidating Finan_4

Condensed Consolidating Financial Information - Condensed Consolidating Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Condensed Income Statements, Captions [Line Items]
Total net revenues	$ 74,594	$ 47,200	$ 24,743	$ 33,508	$ 57,902	$ 61,095	$ 46,001	$ 32,556	$ 180,045	$ 197,554	$ 172,808
Cost of goods sold									120,425	121,915	136,776
Gross profit	37,809	16,475	(1,517)	6,853	23,811	30,109	15,618	6,101	59,620	75,639	36,032
Total operating expenses									113,892	84,338	79,203
Loss from operations	(16,661)	(2,452)	(22,519)	(12,640)	(1,151)	9,936	(3,572)	(13,912)	(54,272)	(8,699)	(43,171)
Interest expense, net	(3,203)	(3,022)	(2,911)	(3,836)	(4,045)	(3,959)	(4,241)	(4,464)	(12,972)	(16,709)	(18,485)
Intercompany interest, net									0	0	0
Equity in earnings (losses) of investments									0	0	0
Other income (expense), net	180	91	84	(791)	209	722	192	(5,068)	(436)	(3,945)	1,350
Loss before income taxes									(67,680)	(29,353)	(60,306)
Income tax expense (benefit)	(587)	2,079	154	1,072	(3,646)	1,686	2,402	(418)	2,718	24	4,421
Net income (loss)									(70,398)	(29,377)	(64,727)
Net income attributable to noncontrolling interests	(246)	(74)	(366)	(87)	(53)	(78)	(418)	(316)	(773)	(865)	(421)
Net loss attributable to ION	$ (19,343)	$ (7,536)	$ (25,866)	$ (18,426)	$ (1,394)	$ 4,935	$ (10,441)	$ (23,342)	(71,171)	(30,242)	(65,148)
Comprehensive net income (loss)									(71,961)	(26,508)	(71,694)
Comprehensive income attributable to noncontrolling interests									(773)	(865)	(421)
Comprehensive net loss attributable to ION									(72,734)	(27,373)	(72,115)
Reportable Legal Entities | ION Geophysical Corporation
Condensed Income Statements, Captions [Line Items]
Total net revenues									0	0	0
Cost of goods sold									0	0	0
Gross profit									0	0	0
Total operating expenses									32,888	39,000	31,438
Loss from operations									(32,888)	(39,000)	(31,438)
Interest expense, net									(13,010)	(16,729)	(18,406)
Intercompany interest, net									1,124	1,084	978
Equity in earnings (losses) of investments									(26,446)	27,696	(19,756)
Other income (expense), net									(196)	(4,610)	3,528
Loss before income taxes									(71,416)	(31,559)	(65,094)
Income tax expense (benefit)									(245)	(1,317)	54
Net income (loss)									(71,171)	(30,242)	(65,148)
Net income attributable to noncontrolling interests									0	0	0
Net loss attributable to ION									(71,171)	(30,242)	(65,148)
Comprehensive net income (loss)									(72,734)	(27,373)	(72,331)
Comprehensive income attributable to noncontrolling interests									0	0	0
Comprehensive net loss attributable to ION									(72,734)	(27,373)	(72,331)
Reportable Legal Entities | The Guarantors
Condensed Income Statements, Captions [Line Items]
Total net revenues									96,649	148,590	91,465
Cost of goods sold									85,186	90,754	87,660
Gross profit									11,463	57,836	3,805
Total operating expenses									29,235	28,020	27,279
Loss from operations									(17,772)	29,816	(23,474)
Interest expense, net									(136)	(107)	(173)
Intercompany interest, net									(12,137)	(6,613)	(4,397)
Equity in earnings (losses) of investments									37,219	67,290	23,368
Other income (expense), net									116	(407)	723
Loss before income taxes									7,290	89,979	(3,953)
Income tax expense (benefit)									(6,711)	(1,427)	1,337
Net income (loss)									14,001	91,406	(5,290)
Net income attributable to noncontrolling interests									0	0	0
Net loss attributable to ION									14,001	91,406	(5,290)
Comprehensive net income (loss)									13,953	91,358	(5,290)
Comprehensive income attributable to noncontrolling interests									0	0	0
Comprehensive net loss attributable to ION									13,953	91,358	(5,290)
Reportable Legal Entities | All Other Subsidiaries
Condensed Income Statements, Captions [Line Items]
Total net revenues									83,396	48,964	81,343
Cost of goods sold									35,239	31,161	49,116
Gross profit									48,157	17,803	32,227
Total operating expenses									51,769	17,318	20,486
Loss from operations									(3,612)	485	11,741
Interest expense, net									174	127	94
Intercompany interest, net									11,013	5,529	3,419
Equity in earnings (losses) of investments									0	0	0
Other income (expense), net									(356)	1,072	(2,901)
Loss before income taxes									7,219	7,213	12,353
Income tax expense (benefit)									9,674	2,768	3,030
Net income (loss)									(2,455)	4,445	9,323
Net income attributable to noncontrolling interests									(773)	(865)	(421)
Net loss attributable to ION									(3,228)	3,580	8,902
Comprehensive net income (loss)									(4,797)	6,550	1,719
Comprehensive income attributable to noncontrolling interests									(773)	(865)	(421)
Comprehensive net loss attributable to ION									(5,570)	5,685	1,298
Consolidating Adjustments
Condensed Income Statements, Captions [Line Items]
Total net revenues									0	0	0
Cost of goods sold									0	0	0
Gross profit									0	0	0
Total operating expenses									0	0	0
Loss from operations									0	0	0
Interest expense, net									0	0	0
Intercompany interest, net									0	0	0
Equity in earnings (losses) of investments									(10,773)	(94,986)	(3,612)
Other income (expense), net									0	0	0
Loss before income taxes									(10,773)	(94,986)	(3,612)
Income tax expense (benefit)									0	0	0
Net income (loss)									(10,773)	(94,986)	(3,612)
Net income attributable to noncontrolling interests									0	0	0
Net loss attributable to ION									(10,773)	(94,986)	(3,612)
Comprehensive net income (loss)									(8,383)	(97,043)	4,208
Comprehensive income attributable to noncontrolling interests									0	0	0
Comprehensive net loss attributable to ION									$ (8,383)	$ (97,043)	$ 4,208

Condensed Consolidating Finan_5

Condensed Consolidating Financial Information - Condensed Consolidating Statement of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net cash provided by (used in) operating activities	$ 7,098	$ 27,612	$ 993
Cash flows from investing activities:
Investment in multi-client data library	(28,276)	(23,710)	(14,884)
Purchase of property, plant, equipment and seismic rental equipment	(1,514)	(1,063)	(1,458)
Proceeds from sale of cost method investments	0	0	2,698
Net cash used in investing activities	(29,790)	(24,773)	(13,644)
Cash flows from financing activities:
Repayments under revolving line of credit	(10,000)	0	(5,000)
Borrowings under revolving line of credit	0	0	15,000
Payments on notes payable and long-term debt	(30,807)	(4,816)	(23,634)
Cost associated with issuance of debt	(1,247)	(53)	(6,744)
Repurchase of common stock	0	0	(964)
Intercompany lending	0	0	0
Proceeds from employee stock purchases and exercise of stock options	214	1,619	0
Payments to repurchase bonds		0
Net proceeds from issuance of stocks	46,999	0	0
Dividend payment to noncontrolling interest	(200)	(100)	0
Other financing activities	(1,151)	(243)	(252)
Net cash provided by (used in) financing activities	3,808	(3,593)	(21,594)
Effect of change in foreign currency exchange rates on cash, cash equivalents and restricted cash	319	(260)	1,386
Net decrease in cash, cash equivalents and restricted cash	(18,565)	(1,014)	(32,859)
Cash, cash equivalents and restricted cash at beginning of period	52,419	53,433	86,292
Cash, cash equivalents and restricted cash at end of period	33,854	52,419	53,433
Reportable Legal Entities | ION Geophysical Corporation
Cash flows from operating activities:
Net cash provided by (used in) operating activities	(37,659)	(22,315)	(30,732)
Cash flows from investing activities:
Investment in multi-client data library	0	0	0
Purchase of property, plant, equipment and seismic rental equipment	(392)	(165)	(73)
Proceeds from sale of cost method investments			2,698
Net cash used in investing activities	(392)	(165)	2,625
Cash flows from financing activities:
Repayments under revolving line of credit	(10,000)		(5,000)
Borrowings under revolving line of credit			15,000
Payments on notes payable and long-term debt	(30,169)	(1,591)	(17,070)
Cost associated with issuance of debt	(1,247)	(53)	(6,744)
Repurchase of common stock			(964)
Intercompany lending	7,983	38,732	31,867
Proceeds from employee stock purchases and exercise of stock options	214	1,619
Payments to repurchase bonds		0
Net proceeds from issuance of stocks	46,999
Dividend payment to noncontrolling interest	(200)	(100)
Other financing activities	(1,151)	(243)	(252)
Net cash provided by (used in) financing activities	12,429	38,364	16,837
Effect of change in foreign currency exchange rates on cash, cash equivalents and restricted cash	0	0	0
Net decrease in cash, cash equivalents and restricted cash	(25,622)	15,884	(11,270)
Cash, cash equivalents and restricted cash at beginning of period	39,707	23,823	35,093
Cash, cash equivalents and restricted cash at end of period	14,085	39,707	23,823
Reportable Legal Entities | The Guarantors
Cash flows from operating activities:
Net cash provided by (used in) operating activities	39,407	73,154	53,107
Cash flows from investing activities:
Investment in multi-client data library	(25,307)	(23,710)	(14,884)
Purchase of property, plant, equipment and seismic rental equipment	(959)	(817)	(313)
Proceeds from sale of cost method investments			0
Net cash used in investing activities	(26,266)	(24,527)	(15,197)
Cash flows from financing activities:
Repayments under revolving line of credit	0		0
Borrowings under revolving line of credit			0
Payments on notes payable and long-term debt	(638)	(3,167)	(6,316)
Cost associated with issuance of debt	0	0	0
Repurchase of common stock			0
Intercompany lending	(12,522)	(45,609)	(34,771)
Proceeds from employee stock purchases and exercise of stock options	0	0
Payments to repurchase bonds		0
Net proceeds from issuance of stocks	0
Dividend payment to noncontrolling interest	0	0
Other financing activities	0	0	0
Net cash provided by (used in) financing activities	(13,160)	(48,776)	(41,087)
Effect of change in foreign currency exchange rates on cash, cash equivalents and restricted cash	0	0	0
Net decrease in cash, cash equivalents and restricted cash	(19)	(149)	(3,177)
Cash, cash equivalents and restricted cash at beginning of period	66	215	3,392
Cash, cash equivalents and restricted cash at end of period	47	66	215
Reportable Legal Entities | All Other Subsidiaries
Cash flows from operating activities:
Net cash provided by (used in) operating activities	5,350	(23,227)	(21,382)
Cash flows from investing activities:
Investment in multi-client data library	(2,969)	0	0
Purchase of property, plant, equipment and seismic rental equipment	(163)	(81)	(1,072)
Proceeds from sale of cost method investments			0
Net cash used in investing activities	(3,132)	(81)	(1,072)
Cash flows from financing activities:
Repayments under revolving line of credit	0		0
Borrowings under revolving line of credit			0
Payments on notes payable and long-term debt	0	(58)	(248)
Cost associated with issuance of debt	0	0	0
Repurchase of common stock			0
Intercompany lending	4,539	6,877	2,904
Proceeds from employee stock purchases and exercise of stock options	0	0
Payments to repurchase bonds		0
Net proceeds from issuance of stocks	0
Dividend payment to noncontrolling interest	0	0
Other financing activities	0	0	0
Net cash provided by (used in) financing activities	4,539	6,819	2,656
Effect of change in foreign currency exchange rates on cash, cash equivalents and restricted cash	319	(260)	1,386
Net decrease in cash, cash equivalents and restricted cash	7,076	(16,749)	(18,412)
Cash, cash equivalents and restricted cash at beginning of period	12,646	29,395	47,807
Cash, cash equivalents and restricted cash at end of period	19,722	$ 12,646	$ 29,395
Consolidating Adjustments
Cash flows from financing activities:
Cash, cash equivalents and restricted cash at end of period	$ 0

Condensed Consolidating Finan_6

Condensed Consolidating Financial Information - Cash Flow, Restricted Cash Reconciliation (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restricted Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 33,551	$ 52,056	$ 52,652
Total cash, cash equivalents, and restricted cash shown in consolidated statements of cash flows	33,854	52,419	53,433	$ 86,292
Prepaid expenses and other current assets
Restricted Cash and Cash Equivalents [Abstract]
Restricted cash	0	60	260
Other long-term assets
Restricted Cash and Cash Equivalents [Abstract]
Restricted cash	303	303	521
Reportable Legal Entities | ION Geophysical Corporation
Restricted Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	13,782	39,344	23,042
Total cash, cash equivalents, and restricted cash shown in consolidated statements of cash flows	14,085	39,707	23,823	35,093
Reportable Legal Entities | ION Geophysical Corporation | Prepaid expenses and other current assets
Restricted Cash and Cash Equivalents [Abstract]
Restricted cash		60	260
Reportable Legal Entities | ION Geophysical Corporation | Other long-term assets
Restricted Cash and Cash Equivalents [Abstract]
Restricted cash	303	303	521
Reportable Legal Entities | The Guarantors
Restricted Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	47	66	215
Total cash, cash equivalents, and restricted cash shown in consolidated statements of cash flows	47	66	215	3,392
Reportable Legal Entities | The Guarantors | Prepaid expenses and other current assets
Restricted Cash and Cash Equivalents [Abstract]
Restricted cash		0	0
Reportable Legal Entities | The Guarantors | Other long-term assets
Restricted Cash and Cash Equivalents [Abstract]
Restricted cash	0	0	0
Reportable Legal Entities | All Other Subsidiaries
Restricted Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	19,722	12,646	29,395
Total cash, cash equivalents, and restricted cash shown in consolidated statements of cash flows	19,722	12,646	29,395	$ 47,807
Reportable Legal Entities | All Other Subsidiaries | Prepaid expenses and other current assets
Restricted Cash and Cash Equivalents [Abstract]
Restricted cash		0	0
Reportable Legal Entities | All Other Subsidiaries | Other long-term assets
Restricted Cash and Cash Equivalents [Abstract]
Restricted cash	0	0	$ 0
Consolidating Adjustments
Restricted Cash and Cash Equivalents [Abstract]
Cash and cash equivalents		$ 0
Total cash, cash equivalents, and restricted cash shown in consolidated statements of cash flows	$ 0

VALUATION AND QUALIFYING ACCO_2

VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowances for doubtful accounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 572	$ 1,443	$ 4,919
Charged (Credited) to Costs and Expenses	222	949	1,834
Deductions	(364)	(1,820)	(5,310)
Balance at End of Year	430	572	1,443
Allowances for doubtful notes receivable
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	4,000	4,000	4,000
Charged (Credited) to Costs and Expenses	0	0	0
Deductions	0	0	0
Balance at End of Year	4,000	4,000	4,000
Valuation allowance on deferred tax assets
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	153,463	217,589	194,255
Charged (Credited) to Costs and Expenses	7,042	(64,126)	23,334
Deductions	0	0	0
Balance at End of Year	160,505	153,463	217,589
Excess and obsolete inventory
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	15,039	15,049	24,475
Charged (Credited) to Costs and Expenses	665	398	429
Deductions	(680)	(408)	(9,855)
Balance at End of Year	$ 15,024	$ 15,039	$ 15,049