TransAtlantic Petroleum (TAT) 10-Q 8 Aug 18 2018 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2018	Aug. 06, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q2
Trading Symbol	TAT
Entity Registrant Name	TRANSATLANTIC PETROLEUM LTD.
Entity Central Index Key	1,092,289
Current Fiscal Year End Date	--12-31
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		50,591,375

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands		Jun. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents		$ 18,715	$ 18,926
Accounts receivable, net
Oil and natural gas sales		17,997	15,808
Joint interest and other		1,121	1,576
Related party		1,153	1,023
Prepaid and other current assets		7,333	3,866
Inventory		6,198	7,494
Total current assets		52,517	48,693
Oil and natural gas properties (successful efforts method)
Proved		173,942	193,647
Unproved		15,969	24,445
Equipment and other property		12,525	14,075
Property and equipment, gross		202,436	232,167
Less accumulated depreciation, depletion and amortization		(114,109)	(129,183)
Property and equipment, net		88,327	102,984
Other long-term assets:
Other assets		661	2,247
Note receivable - related party		6,287	6,726
Total other assets		6,948	8,973
Total assets		147,792	160,650
Current liabilities:
Accounts payable		5,588	4,853
Accounts payable - related party		3,388	3,141
Accrued liabilities	[1]	11,990	10,014
Derivative liability		2,882	2,215
Asset retirement obligations - current		4
Loans payable		19,175	15,625
Total current liabilities		43,027	35,848
Long-term liabilities:
Asset retirement obligations less current portion		4,143	4,727
Accrued liabilities		7,838	8,810
Deferred income taxes		16,957	19,611
Loans payable		11,200	13,000
Total long-term liabilities		40,138	46,148
Total liabilities		83,165	81,996
Commitments and contingencies
Shareholders' equity:
Common shares, $0.10 par value, 100,000,000 shares authorized; 50,591,375 shares and 50,319,156 shares issued and outstanding as of June 30, 2018 and December 31, 2017, respectively		5,059	5,032
Treasury stock		(970)	(970)
Additional paid-in-capital		575,591	575,411
Accumulated other comprehensive loss		(136,218)	(124,766)
Accumulated deficit		(424,884)	(422,103)
Total shareholders' equity		18,578	32,604
Total liabilities, Series A preferred shares and shareholders' equity		147,792	160,650
Series A Preferred Shares [Member]
Long-term liabilities:
Preferred shares, value		21,300	21,300
Related Party [Member] | Series A Preferred Shares [Member]
Long-term liabilities:
Preferred shares, value		$ 24,750	$ 24,750
[1]	Includes income tax payable of $7.3 million and $6.2 million at June 30, 2018 and December 31, 2017, respectively.

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Common shares, par value	$ 0.10	$ 0.10
Common shares, authorized	100,000,000	100,000,000
Common shares, issued	50,591,375	50,319,156
Common shares, outstanding	50,591,375	50,319,156
Accrued Liabilities [Member]
Income tax payable	$ 7.3	$ 6.2
Series A Preferred Shares [Member]
Preferred shares, outstanding	921,000
Unrelated Party [Member] | Series A Preferred Shares [Member]
Preferred shares, par value	$ 0.01	$ 0.01
Preferred shares, authorized	426,000	426,000
Preferred shares, issued	426,000	426,000
Preferred shares, outstanding	426,000	426,000
Preferred shares, liquidation preference per share	$ 50	$ 50
Related Party [Member] | Series A Preferred Shares [Member]
Preferred shares, par value	$ 0.01	$ 0.01
Preferred shares, authorized	495,000	495,000
Preferred shares, issued	495,000	495,000
Preferred shares, outstanding	495,000	495,000
Preferred shares, liquidation preference per share	$ 50	$ 50

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Income (Loss) (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenues:
Oil and natural gas sales	$ 18,100	$ 12,283	$ 34,761	$ 28,051
Sales of purchased natural gas	1		1	654
Other	97	58	362	72
Total revenues	18,198	12,341	35,124	28,777
Costs and expenses:
Production	2,803	2,714	5,672	5,801
Transportation and processing	1,138		2,331
Exploration, abandonment and impairment	191	2	231	108
Cost of purchased natural gas	1		1	568
Seismic and other exploration	59	65	218	80
General and administrative	3,786	3,181	7,123	6,771
Depreciation, depletion and amortization	3,276	4,255	7,735	8,752
Accretion of asset retirement obligations	43	47	89	95
Total costs and expenses	11,297	10,264	23,400	22,175
Operating income	6,901	2,077	11,724	6,602
Other income (expense):
Loss on sale of TBNG				(15,226)
Interest and other expense	(2,091)	(2,288)	(4,873)	(4,659)
Interest and other income	377	188	631	481
(Loss) gain on derivative contracts	(3,141)	676	(3,866)	1,664
Foreign exchange (loss) gain	(1,938)	1,116	(3,996)	(1,007)
Total other expense	(6,793)	(308)	(12,104)	(18,747)
Income (loss) from operations before income taxes	108	1,769	(380)	(12,145)
Income tax expense	(1,114)	(1,203)	(2,401)	(3,338)
Net income (loss)	(1,006)	566	(2,781)	(15,483)
Other comprehensive income (loss):
Foreign currency translation adjustment	(9,109)	2,132	(11,452)	23,051
Comprehensive (loss) income	$ (10,115)	$ 2,698	$ (14,233)	$ 7,568
Basic net earnings (loss) per common share
Continuing operations	$ (0.02)	$ 0.01	$ (0.06)	$ (0.33)
Weighted average common shares outstanding	50,420	47,412	50,397	47,355
Diluted net earnings (loss) per common share
Continuing operations	$ (0.02)	$ 0.01	$ (0.06)	$ (0.33)
Weighted average common and common equivalent shares outstanding	50,420	47,826	50,397	47,355

Consolidated Statement of Equit

Consolidated Statement of Equity (Unaudited) - 6 months ended Jun. 30, 2018 - USD ($) $ in Thousands	Total	Common Shares [Member]	Treasury Stock [Member]	Warrants [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]
Beginning balance at Dec. 31, 2017	$ 32,604	$ 5,032	$ (970)		$ 575,411	$ (124,766)	$ (422,103)
Beginning balance, shares at Dec. 31, 2017	50,319,156	50,319,000	333,000	700,000
Expiration of warrants				(700,000)
Issuance of restricted stock units		$ 27			(27)
Issuance of restricted stock units, shares		272,000
Share-based compensation	$ 218				218
Tax effect of restricted stock	(11)				(11)
Foreign currency translation adjustment	(11,452)					(11,452)
Net loss	(2,781)						(2,781)
Ending balance at Jun. 30, 2018	$ 18,578	$ 5,059	$ (970)		$ 575,591	$ (136,218)	$ (424,884)
Ending balance, shares at Jun. 30, 2018	50,591,375	50,591,000	333,000	0

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands		3 Months Ended				6 Months Ended				12 Months Ended
		Jun. 30, 2018		Jun. 30, 2017		Jun. 30, 2018		Jun. 30, 2017		Dec. 31, 2017
Operating activities:
Net income (loss)		$ (1,006)		$ 566		$ (2,781)		$ (15,483)
Adjustments to reconcile net loss to net cash provided by operating activities:
Share-based compensation						218		414
Foreign currency loss						6,928		143
Loss (gain) on commodity derivative contracts		3,141		(676)		3,866		(1,664)
Cash settlement on derivative contracts						(3,199)		32
Loss on sale of TBNG								15,226
Amortization on loan financing costs						21		61
Deferred income tax expense						1,431		2,479
Exploration, abandonment and impairment		191		2		231		108
Depreciation, depletion and amortization		3,276		4,255		7,735		8,752
Accretion of asset retirement obligations		43		47		89		95		$ 190
Changes in operating assets and liabilities:
Accounts receivable						(4,971)		7,188
Prepaid expenses and other assets						(4,558)		1,340
Accounts payable and accrued liabilities						7,224		(5,114)
Net cash provided by operating activities						12,234		13,577
Investing activities:
Additions to oil and natural gas properties						(10,898)		(11,331)
Additions to equipment and other properties						(548)		(356)
Proceeds from the sale of TBNG								17,779
Net cash (used in) provided by investing activities						(11,446)		6,092
Financing activities:
Tax withholding on restricted share units						(15)		(86)
Loan proceeds						10,000
Loan repayment						(8,250)		(12,775)
Loan repayment - related party								(2,694)
Net cash provided by (used in) financing activities						1,735		(15,555)
Effect of exchange rate on cash flows, cash equivalents, and restricted cash						(4,104)		(1,713)
Net (decrease) increase in cash, cash equivalents and restricted cash						(1,581)		2,401
Cash, cash equivalents and restricted cash, beginning of period	[1]					20,431		15,071		15,071
Cash, cash equivalents and restricted cash, end of period		$ 18,850	[2]	$ 17,472	[2]	18,850	[2]	17,472	[2]	$ 20,431	[1]
Supplemental disclosures:
Cash paid for interest						5,236		4,400
Cash paid for taxes						$ 534		$ 1,460
[1]	The beginning of period balance at December 31, 2016 includes cash and cash equivalents of $10.0 million, restricted cash of $3.5 million in other assets and TBNG cash held for sale of $1.6 million.  The beginning of period balance at December 31, 2017 includes cash and cash equivalents of $18.9 million and restricted cash of $1.5 million in other assets
[2]	The end of period balance at June 30, 2017 includes cash and cash equivalents of $12.3 million and restricted cash of $5.2 million in other assets. The end of period balance at June 30, 2018 includes cash and cash equivalents of $18.7 million and restricted cash of $0.1 million in other assets.

Consolidated Statements of Cas7

Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017
Cash and cash equivalents	$ 10,000	$ 18,715	$ 18,926	$ 12,300
Thrace Basin Natural Gas (Turkiye) Corporation [Member]
Cash held for sale	1,600
Other Assets [Member]
Restricted cash	$ 3,500	$ 100	$ 1,500	$ 5,200

General

General	6 Months Ended
	Jun. 30, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
General	1. General Nature of operations TransAtlantic Petroleum Ltd. (together with its subsidiaries, “we,” “us,” “our,” the “Company” or “TransAtlantic”) is an international oil and natural gas company engaged in acquisition, exploration, development and production. We have focused our operations in countries that have established, yet underexplored petroleum systems, are net importers of petroleum, have an existing petroleum transportation infrastructure and provide favorable commodity pricing, royalty rates and tax rates to exploration and production companies. We hold interests in developed and undeveloped oil and natural gas properties in Turkey and Bulgaria. As of August 6, 2018, approximately 47% of our outstanding common shares were beneficially owned by N. Malone Mitchell 3rd, our chief executive officer and chairman of our board of directors. We are a holding company with two operating segments – Turkey and Bulgaria. Our assets consist of our ownership interests in subsidiaries that primarily own assets in Turkey and Bulgaria. Basis of presentation Our consolidated financial statements are expressed in U.S. Dollars and have been prepared by management in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”). All amounts in the notes to the consolidated financial statements are in U.S. Dollars unless otherwise indicated. The unaudited consolidated financial statements include accounts of the Company and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. In preparing financial statements, management makes informed judgments and estimates that affect the reported amounts of assets and liabilities as of the date of the financial statements and affect the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, management reviews estimates, including those related to fair value measurements associated with acquisitions and financial derivatives, the recoverability and impairment of long-lived assets, contingencies and income taxes. Changes in facts and circumstances may result in revised estimates and actual results may differ from these estimates. Certain information and footnote disclosures normally included in the consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted in this Form 10-Q pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). These consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in our Form 10-K for the year ended December 31, 2017. On February 24, 2017, we closed the sale of our ownership interests in our subsidiary Thrace Basin Natural Gas (Turkiye) Corporation (“TBNG”) for gross proceeds of $20.7 million, and approximate net cash proceeds of $16.1 million, which amounts reflect a $0.2 million post-closing purchase price adjustment. We classified the assets and liabilities of TBNG within the captions “Assets held for sale” and “Liabilities held for sale” on our consolidated balance sheets as of December 31, 2016. Although the sale of TBNG met the threshold to classify its assets and liabilities as held for sale, it didn’t meet the requirements to classify its operations as discontinued as the sale wasn’t considered a strategic shift in our operations. As such, TBNG’s results of operations are classified as continuing operations for all periods presented (See Note 13. “Assets and liabilities held for sale and discontinued operations”). Revenue recognition As explained below, on January 1, 2018, we adopted Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers Our revenue consists of sales under two contracts, one for crude oil and one for natural gas. The crude oil is delivered to the inlet of a processing center and control is passed through a custodian to the customer at that point. We are paid for crude oil at the inlet plus or minus an adjustment for quality. Our natural gas is metered at the inlet of a transportation pipeline and control is passed at that point. We record natural gas sales at the delivery point to the customer, net of any pricing differentials. There is no material inventory remaining at the end of each reporting period. We have previously deducted any transportation costs, processing fees, or adjustments from revenue and recorded the net amount. Under the new revenue guidance, on January 1, 2018, we now record the gross amount of the revenue and records any fees, or deductions as expenses. Our revenue excludes any amounts collected on behalf of third parties.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	6 Months Ended
	Jun. 30, 2018
Accounting Changes And Error Corrections [Abstract]
Recent accounting pronouncements	2. Recent accounting pronouncements In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date. We adopted ASU 2014-09 on January 1, 2018 using the modified retrospective approach. We have a small number of contracts with customers and have identified transactions within the scope of the standard. As a result of adoption of ASU 2014-09, we have determined that it will change our method of recording certain transportation and processing charges that were previously recorded as a reduction of revenues to record such charges as an expense under the new standard. The result of this change was an increase to both revenue and expenses of $2.3 million for the six months ended June 30, 2018. The application of the new standard has no impact on our retained earnings and no impact to our net income on an ongoing basis. During the six months ended June 30, 2017, this standard would have increased both revenue and expenses by $2.3 million. Contracts for the sale of natural gas and crude oil are evidenced by (1) base contracts for the sale and purchase of natural gas or crude oil, which document the general terms and conditions for the sale, and (2) transaction confirmations, which document the terms of each specific sale. Revenue is measured based on consideration specified in the contract with the customer. We recognize revenue in the amount that reflects the consideration we expect to be entitled to in exchange for transferring control of those goods to the customer. Revenues are recognized for the sale of our net share of production volumes. Sales on behalf of other working interest owners and royalty interest owners are not recognized as revenues. The contract consideration in our contracts are typically allocated to specific performance obligations in the contract according to the price stated in the contract, which usually sets the base oil and natural gas prices based on benchmark prices based on volumes and adjustments for product quality. Payment is generally received one or two months after the sale has occurred. Three Months Ended Six Months Ended Three Months Ended Six Months Ended June 30, June 30, June 30, June 30, 2018 2018 2017 2017 (in thousands) Disaggregation of revenue Product type Oil $ 17,830 $ 34,155 $ 13,090 $ 29,144 Natural gas 270 606 317 1,230 Total revenue from customers $ 18,100 $ 34,761 $ 13,407 $ 30,374 *As noted above, prior period amounts have not been adjusted under the modified retrospective method. All of our revenues from contracts with customers represent products transferred at the point in time control is transferred to the customer and are generated in Turkey. Transaction price allocated to remaining performance obligations . A significant number of our product sales are short-term in nature with a contract term of one year or less. For those contracts, we have utilized the practical expedient exempting us from disclosure of the transaction price allocated to remaining performance obligations if the performance obligation is part of a contract that has an original expected duration of one year or less. Contract balances . Receivables from contracts with customers are recorded when the right to consideration becomes unconditional, generally when control of the product has been transferred to the customer. Receivables from contracts with customers were $18.0 million and $15.8 million as of June 30, 2018 and December 31, 2017, respectively, and are reported in accounts receivable, net on our consolidated balance sheets. We currently have no assets or liabilities related to our revenue contracts, including no upfront or rights to deficiency payments. Practical expedients . We have made use of certain practical expedients in adopting the new revenue standard, including the value of unsatisfied performance obligations are not disclosed for (i) contracts with an original expected length of one year or less, (ii) contracts for which we recognize revenue at the amount to which we have the right to invoice, (iii) variable consideration which is allocated entirely to a wholly unsatisfied performance obligation and meets the variable allocation criteria in the standard and (iv) only contracts that are not completed at transition. We have not adjusted the promised amount of consideration for the effects of a significant financing component if we expect, at contract inception, that the period between when we transfer a promised good or service to the customer and when the customer pays for that good or service will be one year or less. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash In May 2017, the FASB issued ASU 2017-09, Scope of Modification Accounting Compensation – Stock Compensation In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815) We have reviewed other recently issued, but not yet adopted, accounting standards in order to determine their effects, if any, on our consolidated results of operations, financial position and cash flows. Based on that review, we believe that none of these pronouncements will have a significant effect on current or future earnings or operations.

Series A Preferred Shares

Series A Preferred Shares	6 Months Ended
	Jun. 30, 2018
Temporary Equity Disclosure [Abstract]
Series A preferred shares	3. Series A Preferred Shares Series A Preferred Shares As of June 30, 2018 and 2017, we had 921,000 outstanding shares of our 12.0% Series A Convertible Redeemable Preferred Shares (“Series A Preferred Shares”). The Series A Preferred Shares contain a substantive conversion option, are mandatorily redeemable and convert into a fixed number of common shares. As a result, under U.S GAAP, we have classified the Series A Preferred Shares within mezzanine equity in our consolidated balance sheets. As of June 30, 2018, there were $21.3 million of Series A Preferred Shares and $24.8 million of Series A Preferred Shares – related party outstanding (See Note 12. “Related party transactions”). Pursuant to the Certificate of Designations for the Series A Preferred Shares (the “Certificate of Designations”), each Series A Preferred Share may be converted at any time, at the option of the holder, into 45.754 common shares (which is equal to an initial conversion price of approximately $1.0928 per common share and is subject to customary adjustments for stock splits, stock dividends, recapitalizations or other fundamental changes). If not converted sooner, on November 4, 2024, we are required to redeem the outstanding Series A Preferred Shares in cash at a price per share equal to the liquidation preference plus accrued and unpaid dividends. At any time on or after November 4, 2020, we may redeem all or a portion of the Series A Preferred Shares at the redemption prices listed below (expressed as a percentage of the liquidation preference amount per share) plus accrued and unpaid dividends to the date of redemption, if the closing sale price of the common shares equals or exceeds 150% of the conversion price then in effect for at least 10 trading days (whether or not consecutive) in a period of 20 consecutive trading days, including the last trading day of such 20 trading day period, ending on, and including, the trading day immediately preceding the business day on which we issue a notice of optional redemption. The redemption prices for the 12-month period starting on the dates below are: Period Commencing Redemption Price November 4, 2020 105.000% November 4, 2021 103.000% November 4, 2022 101.000% November 4, 2023 and thereafter 100.000% Additionally, upon the occurrence of a change of control, we are required to offer to redeem the Series A Preferred Shares within 120 days after the first date on which such change of control occurred, for cash at a redemption price equal to the liquidation preference per share, plus any accrued and unpaid dividends. Dividends on the Series A Preferred Shares are payable quarterly at our election in cash, common shares or a combination of cash and common shares at an annual dividend rate of 12.0% of the liquidation preference if paid all in cash or 16.0% of the liquidation preference if paid in common shares. If paid partially in cash and partially in common shares, the dividend rate on the cash portion is 12.0%, and the dividend rate on the common share portion is 16.0%. Dividends are payable quarterly on March 31, June 30, September 30, and December 31 of each year. The holders of the Series A Preferred Shares also are entitled to participate pro-rata in any dividends paid on the common shares on an as-converted-to-common shares basis. For the three and six months ended June 30, 2018, we paid $1.3 million and $2.6 million, respectively, in cash dividends on the Series A Preferred Shares, which is recorded in our consolidated statements of comprehensive (loss) income under the caption Except as required by Bermuda law, the holders of Series A Preferred Shares have no voting rights, except that for so long as at least 400,000 Series A Preferred Shares are outstanding, the holders of the Series A Preferred Shares voting as a separate class have the right to elect two directors to our Board of Directors. For so long as between 80,000 and 399,999 Series A Preferred Shares are outstanding, the holders of the Series A Preferred Shares voting as a separate class have the right to elect one director to our Board of Directors. Upon less than 80,000 Series A Preferred Shares remaining outstanding, any directors elected by the holders of Series A Preferred Shares shall immediately resign from our Board of Directors. The Certificate of Designation also provides that without the approval of the holders of a majority of the outstanding Series A Preferred Shares, we will not issue indebtedness for money borrowed or other securities which are senior to the Series A Preferred Shares in excess of the greater of (i) $100 million or (ii) 35% of our PV-10 of proved reserves as disclosed in our most recent independent reserve report filed or furnished by us on EDGAR.

Property and equipment

Property and equipment	6 Months Ended
	Jun. 30, 2018
Property Plant And Equipment [Abstract]
Property and equipment	4. Property and equipment Oil and natural gas properties The following table sets forth the capitalized costs under the successful efforts method for our oil and natural gas properties as of: June 30, 2018 December 31, 2017 (in thousands) Oil and natural gas properties, proved: Turkey $ 173,421 $ 193,111 Bulgaria 521 536 Total oil and natural gas properties, proved 173,942 193,647 Oil and natural gas properties, unproved: Turkey 15,969 24,445 Total oil and natural gas properties, unproved 15,969 24,445 Gross oil and natural gas properties 189,911 218,092 Accumulated depletion (108,599 ) (123,225 ) Net oil and natural gas properties $ 81,312 $ 94,867 The decline in oil and natural gas properties during the six months ended June 30, 2018 was primarily driven by the devaluation of the Turkish Lira versus the U.S. Dollar. For the six months ended June 30, 2018, foreign currency translations reduced oil and natural gas properties and increased accumulated other comprehensive loss within shareholders’ equity on our consolidated balance sheet. At June 30, 2018 and December 31, 2017, we excluded $3.3 million and $0.5 million, respectively, from the depletion calculation for proved development wells currently in progress and for costs associated with fields currently not in production. At June 30, 2018, the capitalized costs of our oil and natural gas properties, net of accumulated depletion, included $9.0 million relating to acquisition costs of proved properties, which are being depleted by the unit-of-production method using total proved reserves, and $57.2 million relating to well costs and additional development costs, which are being depleted by the unit-of-production method using proved developed reserves. At December 31, 2017, the capitalized costs of our oil and natural gas properties included $11.2 million relating to acquisition costs of proved properties, which are being amortized by the unit-of-production method using total proved reserves, and $58.7 million relating to well costs and additional development costs, which are being amortized by the unit-of-production method using proved developed reserves. Impairments of proved properties and impairment of exploratory well costs Proved oil and natural gas properties are reviewed for impairment when events and circumstances indicate the carrying value of such properties may not be recoverable. We primarily use Level 3 inputs to determine fair value, including but not limited to, estimates of proved reserves, future commodity prices, the timing and amount of future production and capital expenditures and discount rates commensurate with the risk reflective of the lives remaining for the respective oil and natural gas properties. During the six months ended June 30, 2018 and 2017, we recorded $0.1 million and $0.1 million, respectively, of impairment of proved properties and exploratory well costs which are primarily measured using Level 3 inputs. Capitalized cost greater than one year As of June 30, 2018, we had $2.4 million of exploratory well costs capitalized for the Pinar-1ST well in Turkey, which we spud in March 2014, and $4.5 million of exploratory well costs for the Cavuslu-1 well in Turkey, which we spud in June 2017. Both the Pinar-1ST well and Cavuslu-1 well started producing in 2018. Equipment and other property The historical cost of equipment and other property, presented on a gross basis with accumulated depreciation, is summarized as follows: June 30, 2018 December 31, 2017 (in thousands) Inventory $ 4,254 $ 4,619 Leasehold improvements, office equipment and software 6,272 7,214 Gas gathering system and facilities 224 135 Vehicles 348 343 Other equipment 1,426 1,764 Gross equipment and other property 12,525 14,075 Accumulated depreciation (5,510 ) (5,958 ) Net equipment and other property $ 7,015 $ 8,118 At June 30, 2018, in addition to above, we have classified $6.2 million of inventory as a current asset, which represents our expected inventory consumption in the next twelve months. We classify our materials and supply inventory as a long-term asset because such materials will ultimately be classified as a long-term asset when the material is used in the drilling of a well. At June 30, 2018 and December 31, 2017, we excluded $10.5 million and $12.1 million of inventory, respectively, from depreciation as the inventory had not been placed into service.

Asset Retirement obligations

Asset Retirement obligations	6 Months Ended
	Jun. 30, 2018
Asset Retirement Obligation Disclosure [Abstract]
Asset Retirement obligations	5. Asset retirement obligations The following table summarizes the changes in our asset retirement obligations (“ARO”) for the six months ended June 30, 2018 and for the year ended December 31, 2017: June 30, 2018 December 31, 2017 (in thousands) Asset retirement obligations at beginning of period $ 4,727 $ 4,833 Liabilities settled - (37 ) Foreign exchange change effect (778 ) (259 ) Additions 109 - Accretion expense 89 190 Asset retirement obligations at end of period $ 4,147 $ 4,727 Our ARO is measured using primarily Level 3 inputs. The significant unobservable inputs to this fair value measurement include estimates of plugging costs, remediation costs, inflation rate and well life. The inputs are calculated based on historical data as well as current estimated costs.

Derivative instruments

Derivative instruments	6 Months Ended
	Jun. 30, 2018
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Derivative instruments	6. Derivative instruments We use derivative instruments to manage certain risks related to commodity prices and foreign currency exchange rates. The use of derivative instruments for risk management is covered by operating policies and is closely monitored by our senior management. We do not hold any derivatives for speculative purposes and do not use derivatives with leveraged or complex features. We have not designated the derivative contracts as hedges for accounting purposes, and accordingly, we record the derivative contracts at fair value and recognize changes in fair value in earnings as they occur. Commodity price derivatives To the extent that a legal right of offset exists, we net the value of our derivative contracts with the same counterparty in our consolidated balance sheets. All of our oil derivative contracts are settled based upon Brent crude oil pricing. We recognize gains and losses related to these contracts on a fair value basis in our consolidated statements of comprehensive (loss) income under the caption “(Loss) gain on derivative contracts.” Settlements of derivative contracts are included in operating activities on our consolidated statements of cash flows under the caption “Cash settlement on derivative contracts.” At June 30, 2018 and December 31, 2017, we had outstanding derivative contracts with respect to our future crude oil production as set forth in the tables below: Fair Value of Commodity Derivative Instruments as of June 30, 2018 Weighted Weighted Average Average Quantity Minimum Maximum Price Additional Call Estimated Fair Type Period (Bbl/day) Price (per Bbl) (per Bbl) Ceiling Value of Liability (in thousands) Collar July 1, 2018 - December 31, 2018 440 $ 55.00 $ 70.00 $ - $ (799 ) Collar July 1, 2018 - December 31, 2018 489 $ 56.00 $ 70.00 $ 84.00 (759 ) Total Estimated Fair Value of Liability $ (1,558 ) Fair Value of Commodity Derivative Instruments as of December 31, 2017 Weighted Weighted Average Average Quantity Minimum Maximum Price Additional Call Estimated Fair Type Period (Bbl/day) Price (per Bbl) (per Bbl) Ceiling Value of Liability (in thousands) Collar January 1, 2018 — February 28, 2018 458 $ 50.00 $ 61.50 $ - $ (178 ) Collar January 1, 2018 — March 31, 2018 500 $ 47.00 $ 59.65 $ - (376 ) Collar January 1, 2018 — May 31, 2018 298 $ 47.50 $ 61.00 $ - (286 ) Collar January 1, 2018 — June 30, 2018 746 $ 47.50 $ 57.10 $ - (1,375 ) Total Estimated Fair Value of Liability $ (2,215 ) Foreign currency derivatives To the extent that a legal right of offset exists, we net the value of our derivative contracts with the same counterparty in our consolidated balance sheets. All of our foreign exchange derivative contracts are settled based upon the contract rate. We recognize gains and losses related to these contracts on a fair value basis in our consolidated statements of comprehensive (loss) income under the caption “(Loss) gain on derivative contracts.” Settlements of derivative contracts are included in operating activities on our consolidated statements of cash flows under the caption “Cash settlement on derivative contracts.” At June 30, 2018, we had outstanding derivative contracts with respect to our foreign exchange rates as set forth in the tables below: Fair Value of Currency Derivative Instruments as of June 30, 2018 Buy Sell Estimated Fair Type Buy/Sell Rate Settlement Date Buy Currency Currency Amount Sell Currency Currency Amount Value of Liability (in thousands) FXOPT Buy 4.840 10/16/18 TRY 16,940,000 USD 3,500,000 $ (234 ) FXOPT Buy 4.790 09/03/18 TRY 4,790,000 USD 1,000,000 (169 ) FXFWD Sell 4.930 07/03/18 USD 1,500,000 TRY 7,397,550 (114 ) FXFWD Sell 4.960 07/17/18 USD 3,500,000 TRY 17,351,600 (263 ) FXFWD Sell 4.980 07/31/18 USD 1,500,000 TRY 7,475,250 (112 ) FXFWD Sell 5.010 08/14/18 USD 4,250,000 TRY 21,297,175 (315 ) FXFWD Sell 5.050 09/05/18 USD 1,600,000 TRY 8,085,760 (117 ) Total Estimated Fair Value of Liability $ (1,324 ) During the three months ended June 30, 2018 and 2017, we recorded a net loss on derivative contracts of $3.1 million and a net gain of $0.7 million, respectively. During the six months ended June 30, 2018 and 2017, we recorded a net loss on derivative contracts of $3.9 million and a net gain of $1.7 million, respectively. Balance sheet presentation The following table summarizes both: (i) the gross fair value of our derivative instruments by the appropriate balance sheet classification even when the derivative instruments are subject to netting arrangements and qualify for net presentation in our consolidated balance sheets at June 30, 2018 and December 31, 2017, and (ii) the net recorded fair value as reflected on our consolidated balance sheets at June 30, 2018 and December 31, 2017. As of June 30, 2018 Gross Amount Net Amount of Gross Offset in the Liabilities Amount of Consolidated Presented in the Location on Consolidated Recognized Balance Consolidated Type of Derivative Contract Balance Sheets Liabilities Sheet s Balance Sheets (in thousands) Commodity - crude oil Current liabilities $ 1,558 $ - $ 1,558 Commodity - crude oil Long-term liabilities $ - $ - $ - Foreign exchange Current liabilities $ 1,324 $ - $ 1,324 Foreign exchange Long-term liabilities $ - $ - $ - As of December 31, 2017 Gross Amount Net Amount of Gross Offset in the Liabilities Amount of Consolidated Presented in the Location on Consolidated Recognized Balance Consolidated Type of Derivative Contract Balance Sheets Liabilities Sheets Balance Sheets (in thousands) Commodity - crude oil Current liabilities $ 2,215 $ - $ 2,215 Commodity - crude oil Long-term liabilities $ - $ - $ - Foreign exchange Current liabilities $ - $ - $ - Foreign exchange Long-term liabilities $ - $ - $ -

Loans payable

Loans payable	6 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Loans payable	7. Loans payable As of the dates indicated, our third-party debt consisted of the following: June 30, December 31, 2018 2017 Fixed and floating rate loans (in thousands) Term Loans (1) $ 30,375 $ 28,625 Less: current portion 19,175 15,625 Long-term portion $ 11,200 $ 13,000 _________________________________________________________ (1) Includes the 2018 Term Loan, the 2017 Term Loan, and the 2016 Term Loan (each as defined below and collectively, “Term Loans”). 2016 Term Loan On August 23, 2016, the Turkish branch of TransAtlantic Exploration Mediterranean International Pty Ltd (“TEMI”) entered into a Credit Agreement (the “Credit Agreement”) with DenizBank, A.S. (“DenizBank”). The Credit Agreement is a master agreement pursuant to which DenizBank may make loans to TEMI from time to time pursuant to additional loan agreements. On August 31, 2016, DenizBank entered into a $30.0 million term loan (the “2016 Term Loan”) with TEMI under the Credit Agreement. In addition, we and DenizBank entered into additional agreements with respect to up to $20.0 million of non-cash facilities, including guarantee letters and treasury instruments for future hedging transactions. The 2016 Term Loan bore interest at a fixed rate of 5.25% (plus 0.2625% for Banking and Insurance Transactions Tax per the Turkish government) per annum and was payable in six monthly installments of $1.25 million each through February 2017 and thereafter in twelve monthly installments of $1.88 million each through February 2018. On April 27, 2017, TEMI and DenizBank approved a revised amortization schedule for the 2016 Term Loan. Pursuant to the revised amortization schedule, the maturity date of the 2016 Term Loan was extended from February 2018 to June 2018, and the monthly principal payments were reduced from $1.88 million to $1.38 million. The other terms of the 2016 Term Loan remained unchanged. The 2016 Term Loan was guaranteed by DMLP, Ltd. (“DMLP”), TransAtlantic Turkey, Ltd. (“TransAtlantic Turkey”), Talon Exploration, Ltd. (“Talon Exploration”) and TransAtlantic Worldwide, Ltd. (“TransAtlantic Worldwide”). The 2016 Term Loan contained standard prohibitions on the activities of TEMI as the borrower, including prohibitions on granting of liens on its assets, incurring additional debt, dissolving, liquidating, merging, consolidating, paying dividends, making certain investments, selling assets or transferring revenue, and other similar matters. In addition, the 2016 Term Loan prohibited Amity Oil International Pty Ltd (“Amity”) and Petrogas Petrol Gaz ve Petrokimya Urunleri Insaat Sanayi ve Ticaret A.S. (“Petrogas”) from incurring additional debt. An event of default under the 2016 Term Loan included, among other events, failure to pay principal or interest when due, breach of certain covenants, representations, warranties and obligations, bankruptcy or insolvency and the occurrence of a material adverse effect. The 2016 Term Loan was secured by a pledge of (i) the stock of TEMI, DMLP, TransAtlantic Turkey and Talon Exploration, (ii) substantially all of the assets of TEMI, (iii) certain real estate owned by Petrogas, (iv) the Gundem real estate and Muratli real estate owned by Gundem Turizm Yatirim ve Isletmeleri A.S. (“Gundem”) and (v) certain Diyarbakir real estate owned 80% by N. Malone Mitchell 3 rd On June 28, 2018, we repaid the 2016 Term Loan in full in accordance with its terms. 2017 Term Loan On November 17, 2017, DenizBank entered into a $20.4 million term loan (the “2017 Term Loan”) with TEMI under the Credit Agreement. We will use the proceeds from the 2017 Term Loan for general corporate purposes. The 2017 Term Loan bears interest at a fixed rate of 6.0% (plus 0.3% for Banking and Insurance Transactions Tax per the Turkish government) per annum. The 2017 Term Loan has a grace period which bears no interest or payments due until July 2018 and then is payable in one monthly installment of $1.38 million, nine monthly installments of $1.2 million each through April 2019 and thereafter in eight monthly installments of $1.0 million each through December 2019, with the exception of one monthly installment of $1.2 million occurring in October 2019. The 2017 Term Loan matures in December 2019. Amounts repaid under the 2017 Term Loan may not be re-borrowed, and early repayments under the 2017 Term Loan are subject to early repayment fees. The 2017 Term Loan is guaranteed by Petrogas, Amity, Talon Exploration, DMLP, and TransAtlantic Turkey. The 2017 Term Loan contains standard prohibitions on the activities of TEMI as the borrower, including prohibitions on granting of liens on its assets, incurring additional debt, dissolving, liquidating, merging, consolidating, paying dividends, making certain investments, selling assets or transferring revenue, and other similar matters. In addition, the 2017 Term Loan prohibits Amity and Petrogas from incurring additional debt. An event of default under the 2017 Term Loan includes, among other events, failure to pay principal or interest when due, breach of certain covenants, representations, warranties and obligations, bankruptcy or insolvency and the occurrence of a material adverse effect. The 2017 Term Loan is secured by a pledge of (i) the stock of TEMI, DMLP, TransAtlantic Turkey, and Talon Exploration, (ii) substantially all of the assets of TEMI, (iii) certain real estate owned by Petrogas, (iv) the Gundem real estate and Muratli real estate owned by Gundem, (v) certain Diyarbakir real estate owned 80% by N. Malone Mitchell 3rd and 20% Selami Erdem Uras, and (vi) certain Ankara real estate owned 100% by Mr. Uras. In addition, TEMI assigned its Turkish collection accounts and its receivables from the sale of oil to DenizBank as additional security for the 2017 Term Loan. Gundem is beneficially owned by Mr. Mitchell, his adult children, and Mr. Uras. Mr. Mitchell is our chief executive officer and chairman of our board of directors. Mr. Uras is our vice president, Turkey. At June 30, 2018, we had $20.4 million outstanding under the 2017 Term Loan and no availability, and we were in compliance with the covenants in the 2017 Term Loan. 2018 Term Loan On May 28, 2018, DenizBank entered into a $10.0 million term loan (the “2018 Term Loan”) with TEMI under the Credit Agreement. We will use the proceeds from the 2018 Term Loan for general corporate purposes. The 2018 Term Loan bears interest at a fixed rate of 7.25% (plus 0.3% for Banking and Insurance Transactions Tax per the Turkish government) per annum. The 2018 Term Loan has a grace period through July 2018 during which no payments are due. Thereafter, accrued interest on the 2018 Term Loan is payable monthly and the principal on the 2018 Term Loan is payable in five monthly installments of $0.2 million each through December 2018, four monthly installments of $0.5 million each through April 2019, four monthly installments of $1.0 million each through August 2019, and four monthly installments of $0.75 million each through December 2019. The 2018 Term Loan matures in December 2019. Amounts repaid under the 2018 Term Loan may not be reborrowed, and early repayments under the 2018 Term Loan are subject to early repayment fees. The 2018 Term Loan is guaranteed by Petrogas, Amity, Talon Exploration, DMLP, and TransAtlantic Turkey. The 2018 Term Loan contains standard prohibitions on the activities of TEMI as the borrower, including prohibitions on encumbering or creating restrictions or limitations on all or a part of its assets, revenues, or properties, giving guaranties or sureties, selling assets or transferring revenues, dissolving, liquidating, merging, or consolidating, incurring additional debt, paying dividends, making certain investments, undergoing a change of control, and other similar matters. In addition, the 2018 Term Loan prohibits Amity, Talon Exploration, DMLP, and Transatlantic Turkey from incurring additional debt. An event of default under the 2018 Term Loan includes, among other events, failure to pay principal or interest when due, breach of certain covenants, representations, warranties, and obligations, bankruptcy or insolvency, and the occurrence of a material adverse effect. The 2018 Term Loan is secured by a pledge of (i) the stock of TEMI, DMLP, TransAtlantic Turkey, and Talon Exploration, (ii) substantially all of the assets of TEMI, (iii) certain real estate owned by Petrogas, (iv) certain Gundem real estate and Muratli real estate owned by Gundem, (v) certain Diyarbakir real estate owned 80% by N. Malone Mitchell 3rd and 20% Selami Erdem Uras, and (vi) certain Ankara real estate owned 100% by Mr. Uras. In addition, TEMI assigned its Turkish collection accounts and its receivables from the sale of oil to DenizBank as additional security for the 2018 Term Loan. Gundem is beneficially owned by Mr. Mitchell, his adult children, and Mr. Uras. Mr. Mitchell is our chief executive officer and chairman of our board of directors. Mr. Uras is our vice president, Turkey. At June 30, 2018, we had $10.0 million outstanding under the 2018 Term Loan and no availability, and we were in compliance with the covenants in the 2018 Term Loan. 2017 Notes Our 13.0% Senior Convertible Notes due 2017 (the “2017 Notes”) were issued pursuant to an indenture, dated as of February 20, 2015 (the “Indenture”), between us and U.S. Bank National Association, as trustee (the “Trustee”). The 2017 Notes bore interest at an annual rate of 13.0%, payable semi-annually, in arrears, on January 1 and July 1 of each year. The 2017 Notes matured on July 1, 2017, and on July 3, 2017, we paid off and retired all remaining outstanding 2017 Notes . ANBE Note On December 30, 2015, TransAtlantic Petroleum (USA) Corp (“TransAtlantic USA”) entered into a $5.0 million draw down convertible promissory note (the “ANBE Note”) with ANBE Holdings, L.P. (“ANBE”), an entity owned by the adult children of our chairman and chief executive officer, N. Malone Mitchell 3rd, and controlled by an entity managed by Mr. Mitchell and his wife. The ANBE Note bore interest at a rate of 13.0% per annum. On October 31, 2016, TransAtlantic USA entered into an amendment of the ANBE Note with ANBE (the “ANBE Amendment”). The ANBE Amendment extended the maturity date of the Note from October 31, 2016 to September 30, 2017, provided for the ANBE Note to be repaid in four quarterly installments of $0.9 million each in December 2016 and March, June and September 2017, and provided for monthly payments of interest. On February 27, 2017, we repaid the ANBE Note in full with proceeds from the sale of TBNG and terminated it. Unsecured lines of credit Our wholly-owned subsidiaries operating in Turkey are party to unsecured, non-interest bearing lines of credit with a Turkish bank. At June 30, 2018, we had no outstanding borrowings under these lines of credit.

Contingencies relating to produ

Contingencies relating to production leases and exploration permits	6 Months Ended
	Jun. 30, 2018
Commitments And Contingencies Disclosure [Abstract]
Contingencies relating to production leases and exploration permits	8. Contingencies relating to production leases and exploration permits Selmo We are involved in litigation with persons who claim ownership of a portion of the surface at the Selmo oil field in Turkey. These cases are being vigorously defended by TEMI and Turkish governmental authorities. We do not have enough information to estimate the potential additional operating costs we would incur in the event the purported surface owners’ claims are ultimately successful. Any adjustment arising out of the claims will be recorded when it becomes probable and measurable. Bulgaria During 2012, we were notified that the Bulgarian government may seek to recover approximately $2.0 million in contractual obligations under our Aglen exploration permit work program. Due to the Bulgarian government’s January 2012 ban on fracture stimulation and related activities, a force majeure event under the terms of the exploration permit was recognized by the Bulgarian government. Although we invoked force majeure, we recorded $2.0 million in general and administrative expense relating to our Aglen exploration permit during 2012 for this contractual obligation. In October 2015, the Bulgarian Minister of Energy filed a suit in the Sofia City Court against Direct Petroleum Bulgaria EOOD (“Direct Bulgaria”), claiming $200,000 in liquidated damages for Direct Bulgaria’s alleged failure to fulfill its obligations under the Aglen exploration permit work program. In May 2018, the Sofia City Court concluded that Direct Bulgaria did not fail to fulfill its obligations under the Aglen exploration permit work program as Direct Bulgaria received a force majeure event recognition as a result of a fracture stimulation ban in 2012, imposed by the Bulgarian Parliament, which force majeure event had not been terminated before the expiry of Direct Bulgaria’s obligations under the Aglen exploration permit work program. Additionally, the Sofia City Court concluded that, even if Direct Bulgaria had failed to fulfill its obligations under the Aglen exploration permit work program, the Bulgarian Minister of Energy failed to file suit within the three-year limitation period. Therefore, the Sofia City Court dismissed all claims of the Bulgarian Minister of Energy and ordered the Bulgarian Minister of Energy to pay Direct Bulgaria’s attorney’s fees and legal costs for court experts. In June 2018, the Bulgarian Minister of Energy filed an appeal in the Sofia Court of Appeal. We continue to vigorously defend this claim.

Shareholders' equity

Shareholders' equity	6 Months Ended
	Jun. 30, 2018
Equity [Abstract]
Shareholders' equity	9. Shareholders’ equity Restricted stock units We recorded share-based compensation expense of $0.1 million and $0.3 million for awards of restricted stock units (“RSUs”) for the three months ended June 30, 2018 and 2017, respectively. We recorded share-based compensation expense of $0.2 million and $0.4 million for awards of RSUs for the six months ended June 30, 2018 and 2017, respectively. As of June 30, 2018, we had approximately $0.5 million of unrecognized compensation expense related to unvested RSUs, which is expected to be recognized over a weighted average period of 0.7 years. Earnings per share We account for earnings per share in accordance with ASC Subtopic 260-10, Earnings Per Share The following table presents the basic and diluted earnings per common share computations: Three Months Ended Six Months Ended June 30, June 30, (in thousands, except per share amounts) 2018 2017 2018 2017 Net (loss) earnings from continuing operations $ (1,006 ) $ 566 $ (2,781 ) $ (15,483 ) Basic net (loss) earnings per common share: Shares: Weighted average common shares outstanding 50,420 47,412 50,397 47,355 Basic net (loss) earnings per common share: Continuing operations $ (0.02 ) $ 0.01 $ (0.06 ) $ (0.33 ) Diluted net (loss) earnings per common share: Shares: Weighted average common shares outstanding 50,420 47,826 50,397 47,355 Diluted net (loss) earnings per common share: Continuing operations $ (0.02 ) $ 0.01 $ (0.06 ) $ (0.33 ) Warrants On December 31, 2014, April 24, 2015 and August 13, 2015, we issued 233,334, 233,333 and 233,333 common share purchase warrants (“Warrants”), respectively, to the shareholders of Gundem as consideration for the pledge of Turkish real estate in exchange for an extension of the maturity of a credit agreement between us and a Turkish bank. As consideration for the pledge of Turkish real estate, the independent members of our board of directors approved the issuance of the Warrants to be allocated in accordance with each shareholder’s ownership percentage of Gundem. The Warrants were issued pursuant to a warrant agreement, whereby the

Segment information

Segment information	6 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
Segment information	10. Segment information In accordance with ASC 280, Segment Reporting Corporate Turkey Bulgaria Total (in thousands) For the three months ended June 30, 2018 Total revenues $ - $ 18,198 $ - $ 18,198 (Loss) income from continuing operations before income taxes $ (4,429 ) 4,612 $ (75 ) 108 Capital expenditures $ - $ 5,625 $ - $ 5,625 For the three months ended June 30, 2017 Total revenues $ - $ 12,341 $ - $ 12,341 (Loss) income from continuing operations before income taxes (4,315 ) 6,163 (79 ) 1,769 Capital expenditures $ - $ 4,893 $ - $ 4,893 For the six months ended June 30, 2018 Total revenues $ - $ 35,124 $ - $ 35,124 (Loss) income from continuing operations before income taxes $ (8,222 ) $ 7,963 $ (121 ) $ (380 ) Capital expenditures $ - $ 10,835 $ - $ 10,835 For the six months ended June 30, 2017 Total revenues $ - $ 28,777 $ - $ 28,777 (Loss) income from continuing operations before income taxes (23,236 ) 11,240 (149 ) (12,145 ) Capital expenditures $ - $ 11,331 $ - $ 11,331 Segment assets June 30, 2018 $ 10,890 $ 136,107 $ 795 $ 147,792 December 31, 2017 $ 10,966 $ 149,185 $ 499 $ 160,650

Financial instruments

Financial instruments	6 Months Ended
	Jun. 30, 2018
Fair Value Disclosures [Abstract]
Financial instruments	11. Financial instruments Interest rate risk We are exposed to interest rate risk as a result of our variable rate short-term cash holdings. Foreign currency risk We have underlying foreign currency exchange rate exposure. Our currency exposures primarily relate to transactions denominated in the Bulgarian Lev, the European Union Euro, and the New Turkish Lira (“TRY”). We are also subject to foreign currency exposures resulting from translating the functional currency of our subsidiary financial statements into the U.S. Dollar reporting currency. At June 30, 2018, we had 1.0 million TRY (approximately $0.2 million) in cash and cash equivalents, which exposes us to exchange rate risk based on fluctuations in the value of the TRY. We have not used foreign currency forward contracts to manage exchange rate fluctuations prior to 2018. At June 30, 2018, we were a party to foreign exchange derivative contracts (See Note 6. “Derivative instruments”). Commodity price risk We are exposed to fluctuations in commodity prices for oil and natural gas. Commodity prices are affected by many factors, including, but not limited to, supply and demand. At June 30, 2018 and December 31, 2017, we were a party to commodity derivative contracts (See Note 6. “Derivative instruments”). Concentration of credit risk The majority of our receivables are within the oil and natural gas industry, primarily from our industry partners and from government agencies. Included in receivables are amounts due from Turkiye Petrolleri Anonim Ortakligi (“TPAO”), the national oil company of Turkey, Zorlu Dogal Gaz Ithalat Ihracat ve Toptan Ticaret A.S. (“Zorlu”), a privately owned natural gas distributor in Turkey, and TUPRAS, which purchase the majority of our oil and natural gas production. The receivables are not collateralized. To date, we have experienced minimal bad debts and have no allowance for doubtful accounts for TUPRAS. The majority of our cash and cash equivalents are held by four financial institutions in the United States and Turkey. Fair value measurements Cash and cash equivalents, restricted cash, accounts receivable, accounts payable, accrued liabilities and our loans payable were each estimated to have a fair value approximating the carrying amount at June 30, 2018 and December 31, 2017, due to the short maturity of those instruments. The following table summarizes the valuation of our financial assets and liabilities as of June 30, 2018: Fair Value Measurement Classification Quoted Prices in Active Markets for Identical Assets or Significant Other Significant Liabilities Observable Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Total (in thousands) Measured on a recurring basis Liabilities: Foreign exchange derivative contracts $ - $ (1,324 ) $ - (1,324 ) Commodity derivative contracts - (1,558 ) - (1,558 ) Disclosed but not carried at fair value Liabilities: 2018 Term Loan - - (8,493 ) (8,493 ) 2017 Term Loan - - (18,035 ) (18,035 ) 2016 Term Loan - - - - Total $ - $ (2,882 ) $ (26,528 ) $ (29,410 ) The following table summarizes the valuation of our financial assets and liabilities as of December 31, 2017: Fair Value Measurement Classification Quoted Prices in Active Markets for Identical Assets or Significant Other Significant Liabilities Observable Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Total (in thousands) Measured on a recurring basis Liabilities: Commodity derivative contracts $ - $ (2,215 ) $ - $ (2,215 ) Disclosed but not carried at fair value Liabilities: 2017 Term Loan - - (16,613 ) (16,613 ) 2016 Term Loan - - (7,866 ) (7,866 ) Total $ - $ (2,215 ) $ (24,479 ) $ (26,694 ) We remeasure our derivative contracts on a recurring basis, with changes flowing through earnings. At June 30, 2018 and December 31, 2017, the fair values of the 2018 Term Loan, 2017 Term Loan, and the 2016 Term Loan were estimated using a discounted cash flow analysis based on unobservable Level 3 inputs, including our own credit risk associated with the loans payable.

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jun. 30, 2018
Related Party Transactions [Abstract]
Related party transactions	12. Related party transactions The following table summarizes related party accounts receivable and accounts payable as of the dates indicated: June 30, December 31, 2018 2017 (in thousands) Related party accounts receivable: Riata Management Service Agreement $ 704 $ 576 PSIL MSA 449 447 Total related party accounts receivable $ 1,153 $ 1,023 Related party accounts payable: Riata Management Service Agreement $ 672 $ 341 PSIL MSA 2,213 2,119 Interest payable on Series A Preferred 378 681 Other - board of directors fees 125 - Total related party accounts payable $ 3,388 $ 3,141 Services transactions Effective May 1, 2008, we entered into a service agreement (as amended, the “Service Agreement”), with Longfellow Energy, LP (“Longfellow”), Viking Drilling LLC (“Viking Drilling”), MedOil Supply, LLC and Riata Management, LLC (“Riata Management”) (collectively, the “Service Entities”). Mr. Mitchell and his wife own 100% of Riata Management. In addition, Mr. Mitchell, his wife and his children indirectly own 100% of Longfellow. Riata Management owns 100% of MedOil Supply, LLC. Dalea Partners, LP (“Dalea”), an affiliate of Mr. Mitchell, owns 100% of Viking Drilling. Under the terms of the Service Agreement, we pay, or are paid, for the actual cost of the services rendered plus the actual cost of reasonable expenses on a monthly basis. Under the terms of the Service Agreement, the Service Entities agreed to provide us upon our request certain computer services, payroll and benefits services, insurance administration services and entertainment services, and we and the Service Entities agreed to provide to each other certain management consulting services, oil and natural gas services and general accounting services (collectively, the “Services”). Under the terms of the Service Agreement, we pay, or are paid, for the actual cost of the Services rendered plus the actual cost of reasonable expenses on a monthly basis. We or the Service Entities may terminate the Service Agreement at any time by providing advance notice of termination to the other party. On March 20, 2017, we entered into a second amendment to the Service Agreement among us and Longfellow, Viking Drilling, Riata Management, Longfellow Nemaha, LLC, a Texas limited liability company, Red Rock Minerals, LP, a Delaware limited partnership, Red Rock Advisors, LLC, a Texas limited liability company, Production Solutions International Limited, a Bermuda exempted company, and Nexlube Operating, LLC, a Delaware limited liability company, and their subsidiaries (collectively, the “Riata Entities”), adding and removing certain of the Service Entities and the Riata Entities and expanding the scope of Services. As this agreement is a related party transaction, the independent members of our board of directors reviewed and approved this amendment. As of June 30, 2018, we had $0.7 million of outstanding receivables and $0.7 million of outstanding payables pursuant to the Service Agreement. On March 3, 2016, Mr. Mitchell closed a transaction whereby he sold his interests in Viking Services B.V. (“Viking Services”), the beneficial owner of Viking International Limited (“Viking International”), Viking Petrol Sahasi Hizmetleri A.S. (“VOS”) and Viking Geophysical Services Ltd. (“Viking Geophysical”), to a third party. As part of the transaction, Mr. Mitchell acquired certain equipment used in the performance of stimulation, wireline, workover and similar services, which equipment is owned and operated by Production Solutions International Petrol Arama Hizmetleri Anonim Sirketi (“PSIL”). PSIL is beneficially owned by Dalea Investment Group, LLC, which is controlled by Mr. Mitchell. Consequently, on March 3, 2016, TEMI entered into a master services agreement (the “PSIL MSA”) with PSIL on substantially similar terms to our then current master services agreements with Viking International, VOS and Viking Geophysical. Pursuant to the PSIL MSA, PSIL performs the services on behalf of TEMI and its affiliates. The master services agreement with each of Viking International, VOS and Viking Geophysical currently remain in effect. As of June 30, 2018, we had $0.4 million of outstanding receivables and $2.2 million of outstanding payables pursuant to the PSIL MSA. Office sublease On August 7, 2018 and effective as of June 14, 2018, TransAtlantic USA entered into a sublease agreement (the “Sublease”) with Longfellow to lease corporate office space located at 16803 North Dallas Parkway, Addison, Texas. The Sublease was approved by the audit committee of the board of directors. TransAtlantic USA subleases approximately 10,000 square feet of corporate office space in Addison, Texas. The initial lease term under the Sublease commenced on June 14, 2018 (the “Commencement Date”) and expires on June 30, 2020, unless earlier terminated in accordance with the Sublease. From the Commencement Date until June 30, 2019, TransAtlantic USA is required to pay monthly rent of $18,333.33 to Longfellow, plus utilities, real property taxes, and liability insurance (to the extent that TransAtlantic USA does not obtain its own liability insurance). The monthly rent increases by $416.67 for the period commencing June 30, 2019 and ending June 30, 2021. Pursuant to the Sublease, effective as of June 14, 2018, TransAtlantic USA and Longfellow agreed to terminate the Amended and Restated Office Lease, dated June 26, 2017, by and between TransAtlantic USA and Longfellow. Dalea Amended Note and Pledge Agreement On April 19, 2016, we entered into a note amendment agreement (the “Note Amendment Agreement”) with Mr. Mitchell, and Dalea Partners, LP (“Dalea”), pursuant to which Dalea agreed to deliver an amended and restated promissory note (the “Amended Note”) in favor of us, in the principal sum of $7,964,053, which Amended Note would amend and restate that certain Promissory Note, dated June 13, 2012, made by Dalea in favor of us in the principal amount of $11.5 million (the “Original Note”). The Note Amendment Agreement reduced the principal amount of the Original Note to $7,964,053 in exchange for the cancellation of an account payable of approximately $3.5 million (the “Account Payable”) owed by TransAtlantic Albania Ltd. (“TransAtlantic Albania”), our former subsidiary, to Viking International Limited. We have indemnified a third party for any liability relating to the payment of the Account Payable. Pursuant to the Note Amendment Agreement, on April 19, 2016, we entered into the Amended Note, which amended and restated the Original Note that was issued in connection with our sale of our subsidiaries, Viking International and Viking Geophysical Services, to a joint venture owned by Dalea and Abraaj Investment Management Limited in June 2012. In the Amended Note, we and Dalea acknowledged that (i) while the sale of Dalea’s interest in Viking Services enabled us to take the position that the Original Note was accelerated in accordance with its terms, the principal purpose of including the acceleration events in the Original Note was to ensure that certain oilfield services provided by Viking Services to us would continue to be available to us, and (ii) such services will now be provided pursuant to the PSIL MSA. PSIL is beneficially owned by Dalea Investment Group, LLC, which is controlled by Mr. Mitchell. As a result, the Amended Note revised the events triggering acceleration of the repayment of the Original Note to the following: (i) a reduction of ownership by Dalea (and other controlled affiliates of Mr. Mitchell) of equity interest in PSIL to less than 50%; (ii) the sale or transfer by Dalea or PSIL of all or substantially all of its assets to any person (a “Transferee”) that does not own a controlling interest in Dalea or PSIL and is not controlled by Mr. Mitchell (an “Unrelated Person”), or the subsequent transfer by any Transferee that is not an Unrelated Person of all or substantially all of its assets to an Unrelated Person; (iii) the acquisition by an Unrelated Person of more than 50% of the voting interests of Dalea or PSIL; (iv) termination of the PSIL MSA other than as a result of an uncured default thereunder by TEMI; (v) default by PSIL under the PSIL MSA, which default is not remedied within a period of 30 days after notice thereof to PSIL; and (vi) insolvency or bankruptcy of PSIL. The maturity date of the Amended Note was extended to June 13, 2019. The interest rate on the Amended Note remains at 3.0% per annum and continues to be guaranteed by Mr. Mitchell. The Amended Note contains customary events of default. In addition, pursuant to the Note Amendment Agreement, on April 19, 2016, we entered into a pledge agreement (the “Pledge Agreement”) with Dalea, whereby Dalea pledged the $2.0 million principal amount of the 2017 Notes owned by Dalea (the “Dalea Convertible Notes”), including any future securities for which the Dalea Convertible Notes are converted or exchanged, as security for the performance of Dalea’s obligations under the Amended Note. The Pledge Agreement provides that interest payable to Dalea under the Dalea Convertible Notes (or any future securities for which the Dalea Convertible Notes are converted or exchanged) will be credited first against the outstanding principal balance of the Amended Note and, upon full repayment of the outstanding principal balance of the Amended Note, any accrued and unpaid interest on the Amended Note. The Pledge Agreement contains customary events of default. On November 4, 2016, Dalea exchanged $2.0 million of 2017 Notes for 40,000 Series A Preferred Shares. On June 30, 2016, we entered into a waiver with Dalea, whereby we waived our right under the Pledge Agreement to receive the interest payment due July 1, 2016 under the Dalea Convertible Notes in connection with the payment of 201,459 common shares to Dalea with respect to the 2017 Note interest payment paid on June 30, 2016. During the three and six months ended June 30, 2018, we reduced the principal amount of the Amended Note by $0.1 million and $0.1 million, respectively, for cash dividends paid on the Series A Preferred Shares. As of June 30, 2018, the amount receivable under the Amended Note was $6.3 million. Pledge fee agreements In connection with the pledge of the Gundem real estate and Muratli real estate to DenizBank as collateral for the 2016 Term Loan, on August 31, 2016, we entered into a pledge fee agreement with Gundem (the “Gundem Fee Agreement”) pursuant to which we pay Gundem a fee equal to 5% per annum of the collateral value of the Gundem real estate and Muratli real estate. Pursuant to the Gundem Fee Agreement, the Gundem real estate has a deemed collateral value of $10.0 million and the Muratli real estate has a deemed collateral value of $5.0 million. In connection with the pledge of the Diyarbakir real estate to DenizBank as collateral for the 2016 Term Loan, on August 31, 2016, we entered into a pledge fee agreement with Messrs. Mitchell and Uras (the “Diyarbakir Fee Agreement”) pursuant to which we pay Mr. Mitchell and Selami Erdem Uras a fee of 5% per annum of the collateral value of the Diyarbakir real estate. Mr. Uras is our vice president, Turkey. Pursuant to the Diyarbakir Fee Agreement, the Diyarbakir real estate has a deemed collateral value of $5.0 million. Amounts payable to Mr. Mitchell under the Gundem Fee Agreement and the Diyarbakir Fee Agreement are used to reduce the outstanding principal amount of the Amended Note. During the three and six months ended June 30, 2018, we reduced the principal amount of the Amended Note by $0.2 million and $0.3 million, respectively, for amounts payable under the pledge fee agreements.

Assets and Liabilities Held for

Assets and Liabilities Held for Sale and Discontinued Operations	6 Months Ended
	Jun. 30, 2018
Discontinued Operations And Disposal Groups [Abstract]
Assets and liabilities held for sale and discontinued operations	13. Assets and liabilities held for sale and discontinued operations TBNG assets and liabilities held for sale On October 13, 2016, we entered into a share purchase agreement (the “Purchase Agreement”) with Valeura Energy Netherlands B.V. (“Valeura Netherlands”) for the sale of all of the equity interests in TBNG, our wholly-owned subsidiary. TBNG owned a portion of our interests in the Thrace Basin area in Turkey. We classified the assets and liabilities of TBNG within the captions “Assets held for sale” and “Liabilities held for sale” on our consolidated balance sheets as of December 31, 2016. Although the sale of TBNG met the threshold to classify its assets and liabilities as held for sale, it didn’t meet the requirements to classify its operations as discontinued as the sale wasn’t considered a strategic shift in our operations. As such, TBNG’s results of operations are classified as continuing operations for all periods presented. On February 24, 2017, we closed on the sale of TBNG for gross proceeds of $20.7 million, and approximate net cash proceeds of $16.1 million, which amounts reflect a $0.2 million post-closing purchase price adjustment. For the three months March 31, 2017, we recorded a non-cash net loss of $15.2 million on the sale of TBNG. The loss related to the reclassification of the TBNG accumulated foreign currency translation adjustment that was realized into earnings from accumulated other comprehensive loss within shareholders’ equity, and presented below: Loss on Sale (in thousands) Total cash proceeds for TBNG $ 20,707 Less: TBNG net assets 12,869 Gain on sale before accumulated foreign currency translation adjustment 7,838 Less: TBNG accumulated foreign currency translation adjustment (23,064 ) Net loss on sale of TBNG $ (15,226 ) As a result of the TBNG sale, there were no assets or liabilities held for sale as of December 31, 2017 or as of June 30, 2018. For the three and six months ended June 30, 2018 and 2017, we had no significant operating results from discontinued operations.

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2018
Subsequent Events [Abstract]
Subsequent Events	14. Subsequent Events On August 7, 2018 and effective as of June 14, 2018, TransAtlantic USA entered into the Sublease with Longfellow to lease corporate office space located at 16803 North Dallas Parkway, Addison, Texas (See Note 12. “Related party transactions”).

General (Policies)

General (Policies)	6 Months Ended
	Jun. 30, 2018
Accounting Policies [Abstract]
Nature of operations	Nature of operations TransAtlantic Petroleum Ltd. (together with its subsidiaries, “we,” “us,” “our,” the “Company” or “TransAtlantic”) is an international oil and natural gas company engaged in acquisition, exploration, development and production. We have focused our operations in countries that have established, yet underexplored petroleum systems, are net importers of petroleum, have an existing petroleum transportation infrastructure and provide favorable commodity pricing, royalty rates and tax rates to exploration and production companies. We hold interests in developed and undeveloped oil and natural gas properties in Turkey and Bulgaria. As of August 6, 2018, approximately 47% of our outstanding common shares were beneficially owned by N. Malone Mitchell 3rd, our chief executive officer and chairman of our board of directors. We are a holding company with two operating segments – Turkey and Bulgaria. Our assets consist of our ownership interests in subsidiaries that primarily own assets in Turkey and Bulgaria.
Basis of presentation	Basis of presentation Our consolidated financial statements are expressed in U.S. Dollars and have been prepared by management in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”). All amounts in the notes to the consolidated financial statements are in U.S. Dollars unless otherwise indicated. The unaudited consolidated financial statements include accounts of the Company and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. In preparing financial statements, management makes informed judgments and estimates that affect the reported amounts of assets and liabilities as of the date of the financial statements and affect the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, management reviews estimates, including those related to fair value measurements associated with acquisitions and financial derivatives, the recoverability and impairment of long-lived assets, contingencies and income taxes. Changes in facts and circumstances may result in revised estimates and actual results may differ from these estimates. Certain information and footnote disclosures normally included in the consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted in this Form 10-Q pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). These consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in our Form 10-K for the year ended December 31, 2017. On February 24, 2017, we closed the sale of our ownership interests in our subsidiary Thrace Basin Natural Gas (Turkiye) Corporation (“TBNG”) for gross proceeds of $20.7 million, and approximate net cash proceeds of $16.1 million, which amounts reflect a $0.2 million post-closing purchase price adjustment. We classified the assets and liabilities of TBNG within the captions “Assets held for sale” and “Liabilities held for sale” on our consolidated balance sheets as of December 31, 2016. Although the sale of TBNG met the threshold to classify its assets and liabilities as held for sale, it didn’t meet the requirements to classify its operations as discontinued as the sale wasn’t considered a strategic shift in our operations. As such, TBNG’s results of operations are classified as continuing operations for all periods presented (See Note 13. “Assets and liabilities held for sale and discontinued operations”). Revenue recognition As explained below, on January 1, 2018, we adopted Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers Our revenue consists of sales under two contracts, one for crude oil and one for natural gas. The crude oil is delivered to the inlet of a processing center and control is passed through a custodian to the customer at that point. We are paid for crude oil at the inlet plus or minus an adjustment for quality. Our natural gas is metered at the inlet of a transportation pipeline and control is passed at that point. We record natural gas sales at the delivery point to the customer, net of any pricing differentials. There is no material inventory remaining at the end of each reporting period. We have previously deducted any transportation costs, processing fees, or adjustments from revenue and recorded the net amount. Under the new revenue guidance, on January 1, 2018, we now record the gross amount of the revenue and records any fees, or deductions as expenses. Our revenue excludes any amounts collected on behalf of third parties.

Recent Accounting Pronounceme23

Recent Accounting Pronouncements (Tables)	6 Months Ended
	Jun. 30, 2018
Accounting Changes And Error Corrections [Abstract]
Summary of Disaggregation of Revenue	Revenue is measured based on consideration specified in the contract with the customer. We recognize revenue in the amount that reflects the consideration we expect to be entitled to in exchange for transferring control of those goods to the customer. Revenues are recognized for the sale of our net share of production volumes. Sales on behalf of other working interest owners and royalty interest owners are not recognized as revenues. The contract consideration in our contracts are typically allocated to specific performance obligations in the contract according to the price stated in the contract, which usually sets the base oil and natural gas prices based on benchmark prices based on volumes and adjustments for product quality. Payment is generally received one or two months after the sale has occurred. Three Months Ended Six Months Ended Three Months Ended Six Months Ended June 30, June 30, June 30, June 30, 2018 2018 2017 2017 (in thousands) Disaggregation of revenue Product type Oil $ 17,830 $ 34,155 $ 13,090 $ 29,144 Natural gas 270 606 317 1,230 Total revenue from customers $ 18,100 $ 34,761 $ 13,407 $ 30,374 *As noted above, prior period amounts have not been adjusted under the modified retrospective method.

Series A Preferred Shares (Tabl

Series A Preferred Shares (Tables)	6 Months Ended
	Jun. 30, 2018
Temporary Equity Disclosure [Abstract]
Schedule of Redemption Prices	The redemption prices for the 12-month period starting on the dates below are: Period Commencing Redemption Price November 4, 2020 105.000% November 4, 2021 103.000% November 4, 2022 101.000% November 4, 2023 and thereafter 100.000%

Property and Equipment (Tables)

Property and Equipment (Tables)	6 Months Ended
	Jun. 30, 2018
Property Plant And Equipment [Abstract]
Capitalized Costs under Successful Efforts Method for Oil and Natural Gas Properties	The following table sets forth the capitalized costs under the successful efforts method for our oil and natural gas properties as of: June 30, 2018 December 31, 2017 (in thousands) Oil and natural gas properties, proved: Turkey $ 173,421 $ 193,111 Bulgaria 521 536 Total oil and natural gas properties, proved 173,942 193,647 Oil and natural gas properties, unproved: Turkey 15,969 24,445 Total oil and natural gas properties, unproved 15,969 24,445 Gross oil and natural gas properties 189,911 218,092 Accumulated depletion (108,599 ) (123,225 ) Net oil and natural gas properties $ 81,312 $ 94,867
Historical Cost of Equipment and Other Property on Gross Basis with Accumulated Depreciation	The historical cost of equipment and other property, presented on a gross basis with accumulated depreciation, is summarized as follows: June 30, 2018 December 31, 2017 (in thousands) Inventory $ 4,254 $ 4,619 Leasehold improvements, office equipment and software 6,272 7,214 Gas gathering system and facilities 224 135 Vehicles 348 343 Other equipment 1,426 1,764 Gross equipment and other property 12,525 14,075 Accumulated depreciation (5,510 ) (5,958 ) Net equipment and other property $ 7,015 $ 8,118

Asset Retirement obligations (T

Asset Retirement obligations (Tables)	6 Months Ended
	Jun. 30, 2018
Asset Retirement Obligation Disclosure [Abstract]
Changes in Asset Retirement Obligations	The following table summarizes the changes in our asset retirement obligations (“ARO”) for the six months ended June 30, 2018 and for the year ended December 31, 2017: June 30, 2018 December 31, 2017 (in thousands) Asset retirement obligations at beginning of period $ 4,727 $ 4,833 Liabilities settled - (37 ) Foreign exchange change effect (778 ) (259 ) Additions 109 - Accretion expense 89 190 Asset retirement obligations at end of period $ 4,147 $ 4,727

Derivative instruments (Tables)

Derivative instruments (Tables)	6 Months Ended
	Jun. 30, 2018
Summary of Gross Fair Value of Commodity Derivative Instruments by Balance Sheet Classification	The following table summarizes both: (i) the gross fair value of our derivative instruments by the appropriate balance sheet classification even when the derivative instruments are subject to netting arrangements and qualify for net presentation in our consolidated balance sheets at June 30, 2018 and December 31, 2017, and (ii) the net recorded fair value as reflected on our consolidated balance sheets at June 30, 2018 and December 31, 2017. As of June 30, 2018 Gross Amount Net Amount of Gross Offset in the Liabilities Amount of Consolidated Presented in the Location on Consolidated Recognized Balance Consolidated Type of Derivative Contract Balance Sheets Liabilities Sheet s Balance Sheets (in thousands) Commodity - crude oil Current liabilities $ 1,558 $ - $ 1,558 Commodity - crude oil Long-term liabilities $ - $ - $ - Foreign exchange Current liabilities $ 1,324 $ - $ 1,324 Foreign exchange Long-term liabilities $ - $ - $ - As of December 31, 2017 Gross Amount Net Amount of Gross Offset in the Liabilities Amount of Consolidated Presented in the Location on Consolidated Recognized Balance Consolidated Type of Derivative Contract Balance Sheets Liabilities Sheets Balance Sheets (in thousands) Commodity - crude oil Current liabilities $ 2,215 $ - $ 2,215 Commodity - crude oil Long-term liabilities $ - $ - $ - Foreign exchange Current liabilities $ - $ - $ - Foreign exchange Long-term liabilities $ - $ - $ -
Commodity Price [Member] | Crude Oil [Member]
Summary of Fair Value of Derivative Instruments	At June 30, 2018 and December 31, 2017, we had outstanding derivative contracts with respect to our future crude oil production as set forth in the tables below: Fair Value of Commodity Derivative Instruments as of June 30, 2018 Weighted Weighted Average Average Quantity Minimum Maximum Price Additional Call Estimated Fair Type Period (Bbl/day) Price (per Bbl) (per Bbl) Ceiling Value of Liability (in thousands) Collar July 1, 2018 - December 31, 2018 440 $ 55.00 $ 70.00 $ - $ (799 ) Collar July 1, 2018 - December 31, 2018 489 $ 56.00 $ 70.00 $ 84.00 (759 ) Total Estimated Fair Value of Liability $ (1,558 ) Fair Value of Commodity Derivative Instruments as of December 31, 2017 Weighted Weighted Average Average Quantity Minimum Maximum Price Additional Call Estimated Fair Type Period (Bbl/day) Price (per Bbl) (per Bbl) Ceiling Value of Liability (in thousands) Collar January 1, 2018 — February 28, 2018 458 $ 50.00 $ 61.50 $ - $ (178 ) Collar January 1, 2018 — March 31, 2018 500 $ 47.00 $ 59.65 $ - (376 ) Collar January 1, 2018 — May 31, 2018 298 $ 47.50 $ 61.00 $ - (286 ) Collar January 1, 2018 — June 30, 2018 746 $ 47.50 $ 57.10 $ - (1,375 ) Total Estimated Fair Value of Liability $ (2,215 )
Foreign Exchange Rates [Member]
Summary of Fair Value of Derivative Instruments	At June 30, 2018, we had outstanding derivative contracts with respect to our foreign exchange rates as set forth in the tables below: Fair Value of Currency Derivative Instruments as of June 30, 2018 Buy Sell Estimated Fair Type Buy/Sell Rate Settlement Date Buy Currency Currency Amount Sell Currency Currency Amount Value of Liability (in thousands) FXOPT Buy 4.840 10/16/18 TRY 16,940,000 USD 3,500,000 $ (234 ) FXOPT Buy 4.790 09/03/18 TRY 4,790,000 USD 1,000,000 (169 ) FXFWD Sell 4.930 07/03/18 USD 1,500,000 TRY 7,397,550 (114 ) FXFWD Sell 4.960 07/17/18 USD 3,500,000 TRY 17,351,600 (263 ) FXFWD Sell 4.980 07/31/18 USD 1,500,000 TRY 7,475,250 (112 ) FXFWD Sell 5.010 08/14/18 USD 4,250,000 TRY 21,297,175 (315 ) FXFWD Sell 5.050 09/05/18 USD 1,600,000 TRY 8,085,760 (117 ) Total Estimated Fair Value of Liability $ (1,324 )

Loans payable (Tables)

Loans payable (Tables)	6 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Debt	As of the dates indicated, our third-party debt consisted of the following: June 30, December 31, 2018 2017 Fixed and floating rate loans (in thousands) Term Loans (1) $ 30,375 $ 28,625 Less: current portion 19,175 15,625 Long-term portion $ 11,200 $ 13,000 _________________________________________________________ (1) Includes the 2018 Term Loan, the 2017 Term Loan, and the 2016 Term Loan (each as defined below and collectively, “Term Loans”).

Shareholders' equity (Tables)

Shareholders' equity (Tables)	6 Months Ended
	Jun. 30, 2018
Equity [Abstract]
Basic and Diluted Earnings Per Common Share Computations	The following table presents the basic and diluted earnings per common share computations: Three Months Ended Six Months Ended June 30, June 30, (in thousands, except per share amounts) 2018 2017 2018 2017 Net (loss) earnings from continuing operations $ (1,006 ) $ 566 $ (2,781 ) $ (15,483 ) Basic net (loss) earnings per common share: Shares: Weighted average common shares outstanding 50,420 47,412 50,397 47,355 Basic net (loss) earnings per common share: Continuing operations $ (0.02 ) $ 0.01 $ (0.06 ) $ (0.33 ) Diluted net (loss) earnings per common share: Shares: Weighted average common shares outstanding 50,420 47,826 50,397 47,355 Diluted net (loss) earnings per common share: Continuing operations $ (0.02 ) $ 0.01 $ (0.06 ) $ (0.33 )

Segment information (Tables)

Segment information (Tables)	6 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
Financial Information of Geographic Segments	In accordance with ASC 280, Segment Reporting Corporate Turkey Bulgaria Total (in thousands) For the three months ended June 30, 2018 Total revenues $ - $ 18,198 $ - $ 18,198 (Loss) income from continuing operations before income taxes $ (4,429 ) 4,612 $ (75 ) 108 Capital expenditures $ - $ 5,625 $ - $ 5,625 For the three months ended June 30, 2017 Total revenues $ - $ 12,341 $ - $ 12,341 (Loss) income from continuing operations before income taxes (4,315 ) 6,163 (79 ) 1,769 Capital expenditures $ - $ 4,893 $ - $ 4,893 For the six months ended June 30, 2018 Total revenues $ - $ 35,124 $ - $ 35,124 (Loss) income from continuing operations before income taxes $ (8,222 ) $ 7,963 $ (121 ) $ (380 ) Capital expenditures $ - $ 10,835 $ - $ 10,835 For the six months ended June 30, 2017 Total revenues $ - $ 28,777 $ - $ 28,777 (Loss) income from continuing operations before income taxes (23,236 ) 11,240 (149 ) (12,145 ) Capital expenditures $ - $ 11,331 $ - $ 11,331 Segment assets June 30, 2018 $ 10,890 $ 136,107 $ 795 $ 147,792 December 31, 2017 $ 10,966 $ 149,185 $ 499 $ 160,650

Financial instruments (Tables)

Financial instruments (Tables)	6 Months Ended
	Jun. 30, 2018
Fair Value Disclosures [Abstract]
Valuation of Financial Assets and Liabilities	The following table summarizes the valuation of our financial assets and liabilities as of June 30, 2018: Fair Value Measurement Classification Quoted Prices in Active Markets for Identical Assets or Significant Other Significant Liabilities Observable Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Total (in thousands) Measured on a recurring basis Liabilities: Foreign exchange derivative contracts $ - $ (1,324 ) $ - (1,324 ) Commodity derivative contracts - (1,558 ) - (1,558 ) Disclosed but not carried at fair value Liabilities: 2018 Term Loan - - (8,493 ) (8,493 ) 2017 Term Loan - - (18,035 ) (18,035 ) 2016 Term Loan - - - - Total $ - $ (2,882 ) $ (26,528 ) $ (29,410 ) The following table summarizes the valuation of our financial assets and liabilities as of December 31, 2017: Fair Value Measurement Classification Quoted Prices in Active Markets for Identical Assets or Significant Other Significant Liabilities Observable Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Total (in thousands) Measured on a recurring basis Liabilities: Commodity derivative contracts $ - $ (2,215 ) $ - $ (2,215 ) Disclosed but not carried at fair value Liabilities: 2017 Term Loan - - (16,613 ) (16,613 ) 2016 Term Loan - - (7,866 ) (7,866 ) Total $ - $ (2,215 ) $ (24,479 ) $ (26,694 )

Related Party Transactions (Tab

Related Party Transactions (Tables)	6 Months Ended
	Jun. 30, 2018
Related Party Transactions [Abstract]
Related Party Accounts Receivable and Accounts Payable	The following table summarizes related party accounts receivable and accounts payable as of the dates indicated: June 30, December 31, 2018 2017 (in thousands) Related party accounts receivable: Riata Management Service Agreement $ 704 $ 576 PSIL MSA 449 447 Total related party accounts receivable $ 1,153 $ 1,023 Related party accounts payable: Riata Management Service Agreement $ 672 $ 341 PSIL MSA 2,213 2,119 Interest payable on Series A Preferred 378 681 Other - board of directors fees 125 - Total related party accounts payable $ 3,388 $ 3,141

Assets and Liabilities Held f33

Assets and Liabilities Held for Sale and Discontinued Operations (Tables)	6 Months Ended
	Jun. 30, 2018
Discontinued Operations And Disposal Groups [Abstract]
Reclassification of Accumulated Foreign Currency Translation Adjustment Realized Into Earnings from Accumulated Other Comprehensive Loss	For the three months March 31, 2017, we recorded a non-cash net loss of $15.2 million on the sale of TBNG. The loss related to the reclassification of the TBNG accumulated foreign currency translation adjustment that was realized into earnings from accumulated other comprehensive loss within shareholders’ equity, and presented below: Loss on Sale (in thousands) Total cash proceeds for TBNG $ 20,707 Less: TBNG net assets 12,869 Gain on sale before accumulated foreign currency translation adjustment 7,838 Less: TBNG accumulated foreign currency translation adjustment (23,064 ) Net loss on sale of TBNG $ (15,226 )

General - Additional Informatio

General - Additional Information (Detail) $ in Thousands	Feb. 24, 2017USD ($)	Jun. 30, 2018SegmentContract	Jun. 30, 2017USD ($)	Aug. 06, 2018
Nature Of Business [Line Items]
Number of operating segments | Segment		2
Gross proceeds on sale of ownership interests			$ 17,779
Post closing purchase price adjustment	$ 200
Number of sales contracts consists revenue | Contract		2
Thrace Basin Natural Gas (Turkiye) Corporation [Member]
Nature Of Business [Line Items]
Gross proceeds on sale of ownership interests	20,700
Net cash proceeds on sale of ownership interests	$ 16,100
Subsequent Event [Member]
Nature Of Business [Line Items]
Percentage of common shares owned				47.00%

Recent Accounting Pronounceme35

Recent Accounting Pronouncements - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2018USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2018USD ($)OperatingLease	Jun. 30, 2017USD ($)	Dec. 31, 2017USD ($)
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Increased in expenses	$ 11,297,000	$ 10,264,000	$ 23,400,000	$ 22,175,000
Accumulated deficit	(424,884,000)		(424,884,000)		$ (422,103,000)
Net loss	(1,006,000)	566,000	(2,781,000)	(15,483,000)
Receivables from contracts with customers	17,997,000		$ 17,997,000		15,808,000
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Number of operating leases | OperatingLease			21
Expiration year of last lease			2,022
Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Increased in revenue	18,100,000	$ 13,407,000	$ 34,761,000	30,374,000
Revenue, remaining performance obligation, optional exemption, performance obligation			true
Receivables from contracts with customers	18,000,000		$ 18,000,000		$ 15,800,000
Assets related to revenue contracts	0		0
Liabilities related to revenue contracts	0		0
Upfront or rights to deficiency payments from contract with customers			$ 0
Revenue, practical expedient, initial application and transition, nondisclosure of transaction price allocation to remaining performance obligation			true
Revenue, practical expedient, financing component			true
Accounting Standards Update 2014-09 [Member] | Minimum [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Term of payment received after sale			1 month
Accounting Standards Update 2014-09 [Member] | Maximum [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Term of payment received after sale			2 months
Transaction price allocated to remaining performance obligations contract term			1 year
Exemption period from disclosure			1 year
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Increased in revenue			$ 2,300,000	2,300,000
Increased in expenses			2,300,000	$ 2,300,000
Accumulated deficit	$ 0		0
Net loss			$ 0

Recent Accounting Pronounceme36

Recent Accounting Pronouncements - Summary of Disaggregation of Revenue (Detail) - Accounting Standards Update 2014-09 [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Disaggregation of revenue
Total revenue from customers	$ 18,100	$ 13,407	$ 34,761	$ 30,374
Oil [Member]
Disaggregation of revenue
Total revenue from customers	17,830	13,090	34,155	29,144
Natural Gas [Member]
Disaggregation of revenue
Total revenue from customers	$ 270	$ 317	$ 606	$ 1,230

Series A Preferred Shares - Add

Series A Preferred Shares - Additional Information (Detail) - Series A Preferred Shares [Member]	Nov. 04, 2016USD ($)Director$ / sharesshares	Jun. 30, 2018USD ($)shares	Jun. 30, 2018USD ($)shares	Dec. 31, 2017USD ($)shares	Jun. 30, 2017shares
Redeemable Noncontrolling Interest [Line Items]
Preferred shares, outstanding		921,000	921,000		921,000
Preferred shares, value | $		$ 21,300,000	$ 21,300,000	$ 21,300,000
Preferred stock, dividend rate, percentage			12.00%
Convertible preferred stock, terms of conversion			each Series A Preferred Share may be converted at any time, at the option of the holder, into 45.754 common shares (which is equal to an initial conversion price of approximately $1.0928 per common share and is subject to customary adjustments for stock splits, stock dividends, recapitalizations or other fundamental changes)
Convertible preferred shares issued upon conversion	45.754
Conversion of stock, per share | $ / shares	$ 1.0928
Preferred stock redemption period end date	Nov. 4, 2024
Preferred stock redemption period start date	Nov. 4, 2020
Maximum closing sale price of common shares on conversion price	150.00%
Preferred stock, redemption description			At any time on or after November 4, 2020, we may redeem all or a portion of the Series A Preferred Shares at the redemption prices listed below (expressed as a percentage of the liquidation preference amount per share) plus accrued and unpaid dividends to the date of redemption, if the closing sale price of the common shares equals or exceeds 150% of the conversion price then in effect for at least 10 trading days (whether or not consecutive) in a period of 20 consecutive trading days, including the last trading day of such 20 trading day period, ending on, and including, the trading day immediately preceding the business day on which we issue a notice of optional redemption.
Change in control, offering redemption period	120 days
Preferred stock, dividend payment terms			Dividends on the Series A Preferred Shares are payable quarterly at our election in cash, common shares or a combination of cash and common shares at an annual dividend rate of 12.0% of the liquidation preference if paid all in cash or 16.0% of the liquidation preference if paid in common shares. If paid partially in cash and partially in common shares, the dividend rate on the cash portion is 12.0%, and the dividend rate on the common share portion is 16.0%.
Dividend payment description			Dividends are payable quarterly on March 31, June 30, September 30, and December 31 of each year.
Cash dividend paid | $		$ 1,300,000	$ 2,600,000
Preferred stock voting rights			no voting rights
Certificate of designation description			The Certificate of Designation also provides that without the approval of the holders of a majority of the outstanding Series A Preferred Shares, we will not issue indebtedness for money borrowed or other securities which are senior to the Series A Preferred Shares in excess of the greater of (i) $100 million or (ii) 35% of our PV-10 of proved reserves as disclosed in our most recent independent reserve report filed or furnished by us on EDGAR.
Maximum amount of indebtedness for borrowed money allowed under certificate of designation | $	$ 100,000,000
PV10 reserve value percentage	35.00%
Maximum [Member]
Redeemable Noncontrolling Interest [Line Items]
Right to elect number of directors | Director	2
Minimum [Member]
Redeemable Noncontrolling Interest [Line Items]
Right to elect number of directors | Director	1
Two Director [Member]
Redeemable Noncontrolling Interest [Line Items]
Preferred shares, outstanding	400,000
One Director [Member] | Maximum [Member]
Redeemable Noncontrolling Interest [Line Items]
Preferred shares, outstanding	80,000
One Director [Member] | Minimum [Member]
Redeemable Noncontrolling Interest [Line Items]
Preferred shares, outstanding	399,999
Dividend Paid in Cash [Member]
Redeemable Noncontrolling Interest [Line Items]
Preferred stock, dividend rate, percentage	12.00%
Dividend Paid in Common Shares [Member]
Redeemable Noncontrolling Interest [Line Items]
Preferred stock, dividend rate, percentage	16.00%
Related Party [Member]
Redeemable Noncontrolling Interest [Line Items]
Preferred shares, outstanding		495,000	495,000	495,000
Preferred shares, value | $		$ 24,750,000	$ 24,750,000	$ 24,750,000

Series A Preferred Shares - Sch

Series A Preferred Shares - Schedule of Redemption Prices (Detail) - Series A Preferred Shares [Member]	Nov. 04, 2016
Redeemable Noncontrolling Interest [Line Items]
November 4, 2020	105.00%
November 4, 2021	103.00%
November 4, 2022	101.00%
November 4, 2023 and thereafter	100.00%

Property and Equipment - Capita

Property and Equipment - Capitalized Costs under Successful Efforts Method for Oil and Natural Gas Properties (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Oil and natural gas properties, proved	$ 173,942	$ 193,647
Oil and natural gas properties, unproved	15,969	24,445
Gross oil and natural gas properties	189,911	218,092
Accumulated depletion	(108,599)	(123,225)
Net oil and natural gas properties	81,312	94,867
Turkey [Member]
Property Plant And Equipment [Line Items]
Oil and natural gas properties, proved	173,421	193,111
Oil and natural gas properties, unproved	15,969	24,445
Bulgaria [Member]
Property Plant And Equipment [Line Items]
Oil and natural gas properties, proved	$ 521	$ 536

Property and Equipment - Additi

Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Proved development wells excluded from depletion	$ 3,300		$ 500
Acquisition costs of proved properties	9,000		11,200
Well costs and additional development costs	57,200		58,700
Exploratory dry hole costs	100	$ 100
Inventory	6,198		7,494
Inventory [Member]
Property Plant And Equipment [Line Items]
Property plant and equipment excluded from depreciation	10,500		$ 12,100
Pinar - 1ST well [Member] | Turkey [Member]
Property Plant And Equipment [Line Items]
Exploratory drilling costs capitalized	2,400
Cavuslu-1 Well [Member] | Turkey [Member]
Property Plant And Equipment [Line Items]
Exploratory drilling costs capitalized	$ 4,500

Property and Equipment - Histor

Property and Equipment - Historical Cost of Equipment and Other Property on Gross Basis with Accumulated Depreciation (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Gross equipment and other property	$ 12,525	$ 14,075
Accumulated depreciation	(5,510)	(5,958)
Net equipment and other property	7,015	8,118
Other equipment [Member]
Property Plant And Equipment [Line Items]
Gross equipment and other property	1,426	1,764
Inventory [Member]
Property Plant And Equipment [Line Items]
Gross equipment and other property	4,254	4,619
Vehicles [Member]
Property Plant And Equipment [Line Items]
Gross equipment and other property	348	343
Leasehold improvements, office equipment and software [Member]
Property Plant And Equipment [Line Items]
Gross equipment and other property	6,272	7,214
Gas gathering system and facilities [Member]
Property Plant And Equipment [Line Items]
Gross equipment and other property	$ 224	$ 135

Asset Retirement Obligations -

Asset Retirement Obligations - Changes in Asset Retirement Obligations (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Asset Retirement Obligation Disclosure [Abstract]
Asset retirement obligations at beginning of period			$ 4,727	$ 4,833	$ 4,833
Liabilities settled					(37)
Foreign exchange change effect			(778)		(259)
Additions			109
Accretion expense	$ 43	$ 47	89	$ 95	190
Asset retirement obligations at end of period	$ 4,147		$ 4,147		$ 4,727

Derivative Instruments - Summar

Derivative Instruments - Summary of Fair Value of Commodity Derivative Instruments of Future Crude Oil Production (Detail) - Commodity Price [Member] $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2018USD ($)$ / bbl$ / Callbbl	Dec. 31, 2017USD ($)$ / bblbbl
Derivatives Fair Value [Line Items]
Estimated Fair Value of Liability | $	$ (1,558)	$ (2,215)
Collar - July 1, 2018 - December 31, 2018 [Member]
Derivatives Fair Value [Line Items]
Quantity (Bbl/day) | bbl	440
Collars Weighted Average Minimum Price (per Bbl)	55
Weighted Average Maximum Price (per Bbl)	70
Estimated Fair Value of Liability | $	$ (799)
Collar - July 1, 2018 - December 31, 2018 [Member]
Derivatives Fair Value [Line Items]
Quantity (Bbl/day) | bbl	489
Collars Weighted Average Minimum Price (per Bbl)	56
Weighted Average Maximum Price (per Bbl)	70
Additional Call Ceiling | $ / Call	84
Estimated Fair Value of Liability | $	$ (759)
Collar - January 1, 2018 - February 28, 2018 [Member]
Derivatives Fair Value [Line Items]
Quantity (Bbl/day) | bbl		458
Collars Weighted Average Minimum Price (per Bbl)		50
Weighted Average Maximum Price (per Bbl)		61.50
Estimated Fair Value of Liability | $		$ (178)
Collar - January 1, 2018 - March 31, 2018 [Member]
Derivatives Fair Value [Line Items]
Quantity (Bbl/day) | bbl		500
Collars Weighted Average Minimum Price (per Bbl)		47
Weighted Average Maximum Price (per Bbl)		59.65
Estimated Fair Value of Liability | $		$ (376)
Collar - January 1, 2018 - May 31, 2018 [Member]
Derivatives Fair Value [Line Items]
Quantity (Bbl/day) | bbl		298
Collars Weighted Average Minimum Price (per Bbl)		47.50
Weighted Average Maximum Price (per Bbl)		61
Estimated Fair Value of Liability | $		$ (286)
Collar - January 1, 2018 - June 30, 2018 [Member]
Derivatives Fair Value [Line Items]
Quantity (Bbl/day) | bbl		746
Collars Weighted Average Minimum Price (per Bbl)		47.50
Weighted Average Maximum Price (per Bbl)		57.10
Estimated Fair Value of Liability | $		$ (1,375)

Derivative Instruments - Summ44

Derivative Instruments - Summary of Fair Value of Currency Derivative Instruments (Detail) - Foreign Exchange Rates [Member] ₺ in Thousands, $ in Thousands	6 Months Ended
	Jun. 30, 2018USD ($)	Jun. 30, 2018TRY (₺)
Derivatives Fair Value [Line Items]
Estimated Fair Value of Liability	$ (1,324)
Currency Derivative Instruments One [Member]
Derivatives Fair Value [Line Items]
Type	FXOPT	FXOPT
Buy/Sell	Buy	Buy
Rate	4.840
Settlement Date	Oct. 16, 2018	Oct. 16, 2018
Buy Currency	TRY	TRY
Buy Currency Amount | ₺		₺ 16,940,000
Sell Currency	USD	USD
Sell Currency Amount	$ 3,500,000
Estimated Fair Value of Liability	$ (234)
Currency Derivative Instruments Two [Member]
Derivatives Fair Value [Line Items]
Type	FXOPT	FXOPT
Buy/Sell	Buy	Buy
Rate	4.790
Settlement Date	Sep. 3, 2018	Sep. 3, 2018
Buy Currency	TRY	TRY
Buy Currency Amount | ₺		₺ 4,790,000
Sell Currency	USD	USD
Sell Currency Amount	$ 1,000,000
Estimated Fair Value of Liability	$ (169)
Currency Derivative Instruments Three [Member]
Derivatives Fair Value [Line Items]
Type	FXFWD	FXFWD
Buy/Sell	Sell	Sell
Rate	4.930
Settlement Date	Jul. 3, 2018	Jul. 3, 2018
Buy Currency	USD	USD
Buy Currency Amount	$ 1,500,000
Sell Currency	TRY	TRY
Sell Currency Amount | ₺		₺ 7,397,550
Estimated Fair Value of Liability	$ (114)
Currency Derivative Instruments Four [Member]
Derivatives Fair Value [Line Items]
Type	FXFWD	FXFWD
Buy/Sell	Sell	Sell
Rate	4.960
Settlement Date	Jul. 17, 2018	Jul. 17, 2018
Buy Currency	USD	USD
Buy Currency Amount	$ 3,500,000
Sell Currency	TRY	TRY
Sell Currency Amount | ₺		₺ 17,351,600
Estimated Fair Value of Liability	$ (263)
Currency Derivative Instruments Five [Member]
Derivatives Fair Value [Line Items]
Type	FXFWD	FXFWD
Buy/Sell	Sell	Sell
Rate	4.980
Settlement Date	Jul. 31, 2018	Jul. 31, 2018
Buy Currency	USD	USD
Buy Currency Amount	$ 1,500,000
Sell Currency	TRY	TRY
Sell Currency Amount | ₺		₺ 7,475,250
Estimated Fair Value of Liability	$ (112)
Currency Derivative Instruments Six [Member]
Derivatives Fair Value [Line Items]
Type	FXFWD	FXFWD
Buy/Sell	Sell	Sell
Rate	5.010
Settlement Date	Aug. 14, 2018	Aug. 14, 2018
Buy Currency	USD	USD
Buy Currency Amount	$ 4,250,000
Sell Currency	TRY	TRY
Sell Currency Amount | ₺		₺ 21,297,175
Estimated Fair Value of Liability	$ (315)
Currency Derivative Instruments Seven [Member]
Derivatives Fair Value [Line Items]
Type	FXFWD	FXFWD
Buy/Sell	Sell	Sell
Rate	5.050
Settlement Date	Sep. 5, 2018	Sep. 5, 2018
Buy Currency	USD	USD
Buy Currency Amount	$ 1,600,000
Sell Currency	TRY	TRY
Sell Currency Amount | ₺		₺ 8,085,760
Estimated Fair Value of Liability	$ (117)

Derivative Instruments - Additi

Derivative Instruments - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Derivative Instruments And Hedging Activities Disclosure [Abstract]
(Loss) gain on derivative contracts	$ (3,141)	$ 676	$ (3,866)	$ 1,664

Derivative Instruments - Summ46

Derivative Instruments - Summary of Gross Fair Value of Derivative Instruments by Balance Sheet Classification (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Derivatives Fair Value [Line Items]
Net Amount of Liabilities Presented in the Consolidated Balance Sheets, Current Liabilities	$ 2,882	$ 2,215
Commodity [Member]
Derivatives Fair Value [Line Items]
Gross Amount of Recognized Liabilities	1,558	2,215
Commodity [Member] | Crude Oil [Member] | Current Liabilities [Member]
Derivatives Fair Value [Line Items]
Gross Amount of Recognized Liabilities	1,558	2,215
Net Amount of Liabilities Presented in the Consolidated Balance Sheets, Current Liabilities	1,558	$ 2,215
Foreign Exchange [Member]
Derivatives Fair Value [Line Items]
Gross Amount of Recognized Liabilities	(1,324)
Foreign Exchange [Member] | Current Liabilities [Member]
Derivatives Fair Value [Line Items]
Gross Amount of Recognized Liabilities	1,324
Net Amount of Liabilities Presented in the Consolidated Balance Sheets, Current Liabilities	$ 1,324

Loans Payable - Debt (Detail)

Loans Payable - Debt (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Term Loan	$ 30,375	$ 28,625
Less: current portion	19,175	15,625
Long-term portion	$ 11,200	$ 13,000

Loans Payable - Additional Info

Loans Payable - Additional Information (Detail)

Apr. 27, 2017USD ($)

Oct. 31, 2016Installment

Sep. 30, 2017USD ($)

Jun. 30, 2017USD ($)

Mar. 31, 2017USD ($)

Dec. 31, 2016USD ($)

Jun. 30, 2018USD ($)

May 28, 2018USD ($)

Dec. 31, 2017USD ($)

Nov. 17, 2017USD ($)

Aug. 31, 2016USD ($)

Dec. 30, 2015USD ($)

Line Of Credit Facility [Line Items]

Loans payable

$ 30,375,000

$ 28,625,000

Non-cash Facilities [Member] | DenizBank [Member]

Line Of Credit Facility [Line Items]

Line Of Credit Facility Maximum Borrowing Capacity

$ 20,000,000

2016 TEMI Term Loan [Member]

Line Of Credit Facility [Line Items]

Debt instrument interest rate stated percentage

5.25%

Debt instrument interest rate basis for effective rate

The 2016 Term Loan bore interest at a fixed rate of 5.25% (plus 0.2625% for Banking and Insurance Transactions Tax per the Turkish government)

Debt instrument payment terms

Payable in six monthly installments of $1.25 million each through February 2017 and thereafter in twelve monthly installments of $1.88 million each through February 2018.

Amount of each installment payable through February 2017

$ 1,250,000

Amount of each installment payable through February 2018

$ 1,880,000

Line of credit facility, expiration date

Feb. 28, 2018

2016 TEMI Term Loan [Member] | Turkish Banking and Insurance Transactions Tax Rate [Member]

Line Of Credit Facility [Line Items]

Debt instrument basis spread on variable rate

0.2625%

2016 TEMI Term Loan [Member] | Credit Agreement [Member] | DenizBank [Member]

Line Of Credit Facility [Line Items]

Line of credit facility, initiation date

Aug. 31, 2016

Line Of Credit Facility Maximum Borrowing Capacity

$ 30,000,000

Line of credit facility, expiration date

Jun. 30, 2018

Debt instrument, monthly payments

$ 1,380,000

2016 TEMI Term Loan [Member] | Line of Credit [Member] | N. Malone Mitchell 3rd [Member]

Line Of Credit Facility [Line Items]

Line of credit facility ownership percentage

80.00%

2016 TEMI Term Loan [Member] | Line of Credit [Member] | Selami Erdem Uras [Member]

Line Of Credit Facility [Line Items]

Line of credit facility ownership percentage

20.00%

2017 Term Loan [Member]

Line Of Credit Facility [Line Items]

Debt instrument interest rate stated percentage

6.00%

Debt instrument interest rate basis for effective rate

The 2017 Term Loan bears interest at a fixed rate of 6.0% (plus 0.3% for Banking and Insurance Transactions Tax per the Turkish government) per annum.

Debt instrument payment terms

The 2017 Term Loan has a grace period which bears no interest or payments due until July 2018 and then is payable in one monthly installment of $1.38 million, nine monthly installments of $1.2 million each through April 2019 and thereafter in eight monthly installments of $1.0 million each through December 2019, with the exception of one monthly installment of $1.2 million occurring in October 2019.

Line of credit facility, expiration date

Dec. 31, 2019

2017 Term Loan [Member] | Due until July 2018 [Member]

Line Of Credit Facility [Line Items]

Debt instrument interest rate stated percentage

0.00%

Amount of each installment payable

$ 0

2017 Term Loan [Member] | One Monthly Installment Payable through April 2019 [Member]

Line Of Credit Facility [Line Items]

Amount of each installment payable

1,380,000

2017 Term Loan [Member] | Nine Monthly Installments Payable through April 2019 [Member]

Line Of Credit Facility [Line Items]

Amount of each installment payable

1,200,000

2017 Term Loan [Member] | Eight Monthly Installments Payable through December 2019 [Member]

Line Of Credit Facility [Line Items]

Amount of each installment payable

1,000,000

2017 Term Loan [Member] | One Monthly Installment Occurring in October 2019 [Member]

Line Of Credit Facility [Line Items]

Amount of each installment payable occurring in October 2019

$ 1,200,000

2017 Term Loan [Member] | Turkish Banking and Insurance Transactions Tax Rate [Member]

Line Of Credit Facility [Line Items]

Debt instrument basis spread on variable rate

0.30%

2017 Term Loan [Member] | Credit Agreement [Member] | DenizBank [Member]

Line Of Credit Facility [Line Items]

Line of credit facility, initiation date

Nov. 17, 2017

Line Of Credit Facility Maximum Borrowing Capacity

$ 20,400,000

2017 Term Loan [Member] | Line of Credit [Member]

Line Of Credit Facility [Line Items]

Loans payable

$ 20,400,000

2017 Term Loan [Member] | Line of Credit [Member] | N. Malone Mitchell 3rd [Member]

Line Of Credit Facility [Line Items]

Line of credit facility ownership percentage

80.00%

2017 Term Loan [Member] | Line of Credit [Member] | Selami Erdem Uras [Member]

Line Of Credit Facility [Line Items]

Line of credit facility ownership percentage

20.00%

2017 Term Loan [Member] | Line of Credit [Member] | Mr. Uras [Member]

Line Of Credit Facility [Line Items]

Line of credit facility ownership percentage

100.00%

2018 Term Loan [Member]

Line Of Credit Facility [Line Items]

Debt instrument interest rate stated percentage

7.25%

Debt instrument interest rate basis for effective rate

The 2018 Term Loan bears interest at a fixed rate of 7.25% (plus 0.3% for Banking and Insurance Transactions Tax per the Turkish government) per annum.

Debt instrument payment terms

The 2018 Term Loan has a grace period through July 2018 during which no payments are due. Thereafter, accrued interest on the 2018 Term Loan is payable monthly and the principal on the 2018 Term Loan is payable in five monthly installments of $0.2 million each through December 2018, four monthly installments of $0.5 million each through April 2019, four monthly installments of $1.0 million each through August 2019, and four monthly installments of $0.75 million each through December 2019.

Line of credit facility, expiration date

Dec. 31, 2019

2018 Term Loan [Member] | Due through July 2018 [Member]

Line Of Credit Facility [Line Items]

Amount of each installment payable

$ 0

2018 Term Loan [Member] | Five Monthly Installments Payable through December 2018 [Member]

Line Of Credit Facility [Line Items]

Amount of each installment payable

200,000

2018 Term Loan [Member] | Four Monthly Installments Payable through April 2019 [Member]

Line Of Credit Facility [Line Items]

Amount of each installment payable

500,000

2018 Term Loan [Member] | Four Monthly Installments Payable through August 2019 [Member]

Line Of Credit Facility [Line Items]

Amount of each installment payable

1,000,000

2018 Term Loan [Member] | Four Monthly Installments Payable through December 2019 [Member]

Line Of Credit Facility [Line Items]

Amount of each installment payable

$ 750,000

2018 Term Loan [Member] | Turkish Banking and Insurance Transactions Tax Rate [Member]

Line Of Credit Facility [Line Items]

Debt instrument basis spread on variable rate

0.30%

2018 Term Loan [Member] | Credit Agreement [Member] | DenizBank [Member]

Line Of Credit Facility [Line Items]

Line of credit facility, initiation date

May 28, 2018

Line Of Credit Facility Maximum Borrowing Capacity

$ 10,000,000

2018 Term Loan [Member] | Line of Credit [Member]

Line Of Credit Facility [Line Items]

Loans payable

$ 10,000,000

2018 Term Loan [Member] | Line of Credit [Member] | N. Malone Mitchell 3rd [Member]

Line Of Credit Facility [Line Items]

Line of credit facility ownership percentage

80.00%

2018 Term Loan [Member] | Line of Credit [Member] | Selami Erdem Uras [Member]

Line Of Credit Facility [Line Items]

Line of credit facility ownership percentage

20.00%

2018 Term Loan [Member] | Line of Credit [Member] | Mr. Uras [Member]

Line Of Credit Facility [Line Items]

Line of credit facility ownership percentage

100.00%

13.0% Senior Convertible Notes Due 2017 [Member] | Convertible Debt [Member]

Line Of Credit Facility [Line Items]

Debt instrument interest rate stated percentage

13.00%

Frequency of payments

semi-annually

Debt instrument, maturity date

Jul. 1, 2017

ANBE Note [Member] | TransAtlantic USA [Member]

Line Of Credit Facility [Line Items]

Number of installments | Installment

4

Debt instrument, principal installments

$ 900,000

$ 900,000

$ 900,000

$ 900,000

ANBE Note [Member] | TransAtlantic USA [Member] | Convertible Promissory Note [Member]

Line Of Credit Facility [Line Items]

Line Of Credit Facility Maximum Borrowing Capacity

$ 5,000,000

Debt instrument interest rate stated percentage

13.00%

Line of credit facility borrowing capacity

$ 3,600,000

Extender ANBE Note [Member] | TransAtlantic USA [Member]

Line Of Credit Facility [Line Items]

Debt instrument, maturity date

Sep. 30, 2017

Unsecured lines of credit [Member]

Line Of Credit Facility [Line Items]

Loans payable

$ 0

Turkey [Member] | 2016 TEMI Term Loan [Member] | Credit Agreement [Member] | DenizBank [Member]

Line Of Credit Facility [Line Items]

Line of credit facility, initiation date

Aug. 23, 2016

Contingencies Relating to Pro49

Contingencies Relating to Production Leases and Exploration Permits - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Oct. 31, 2015	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2012
Loss Contingencies [Line Items]
General and administrative		$ 3,786,000	$ 3,181,000	$ 7,123,000	$ 6,771,000
Bulgaria [Member]
Loss Contingencies [Line Items]
Recovery of contractual obligations						$ 2,000,000
Liquidated damages, claim amount	$ 200,000
Bulgaria [Member] | Aglen Exploration Permit Work Program [Member]
Loss Contingencies [Line Items]
General and administrative						$ 2,000,000

Shareholders' Equity - Addition

Shareholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	Aug. 13, 2015	Apr. 24, 2015	Dec. 31, 2014	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Common share purchase warrants issued	233,333	233,333	233,334
Common share purchase warrants, exercise price	$ 2.99	$ 5.65	$ 5.99
Warrants [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Common share purchase				1		1
Restricted Stock Units [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense				$ 0.1	$ 0.3	$ 0.2	$ 0.4
Unrecognized compensation expense				$ 0.5		$ 0.5
Unrecognized compensation expense recognition period						8 months 12 days
Dilutive securities included in the calculation of diluted earnings per share				0		0

Shareholders' Equity - Basic an

Shareholders' Equity - Basic and Diluted Earnings Per Common Share Computations (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Equity [Abstract]
Net (loss) earnings from continuing operations	$ (1,006)	$ 566	$ (2,781)	$ (15,483)
Weighted average common shares outstanding	50,420	47,412	50,397	47,355
Continuing operations	$ (0.02)	$ 0.01	$ (0.06)	$ (0.33)
Weighted average common shares outstanding	50,420	47,826	50,397	47,355
Continuing operations	$ (0.02)	$ 0.01	$ (0.06)	$ (0.33)

Segment Information - Additiona

Segment Information - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2018Segment
Segment Reporting [Abstract]
Number of reportable geographic segments	2

Segment Information - Financial

Segment Information - Financial Information of Geographic Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total revenues	$ 18,198	$ 12,341	$ 35,124	$ 28,777
(Loss) income from continuing operations before income taxes	108	1,769	(380)	(12,145)
Capital expenditures	5,625	4,893	10,835	11,331
Segment assets	147,792		147,792		$ 160,650
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
(Loss) income from continuing operations before income taxes	(4,429)	(4,315)	(8,222)	(23,236)
Segment assets	10,890		10,890		10,966
Operating Segments [Member] | Turkey [Member]
Segment Reporting Information [Line Items]
Total revenues	18,198	12,341	35,124	28,777
(Loss) income from continuing operations before income taxes	4,612	6,163	7,963	11,240
Capital expenditures	5,625	4,893	10,835	11,331
Segment assets	136,107		136,107		149,185
Operating Segments [Member] | Bulgaria [Member]
Segment Reporting Information [Line Items]
(Loss) income from continuing operations before income taxes	(75)	$ (79)	(121)	$ (149)
Segment assets	$ 795		$ 795		$ 499

Financial Instruments - Additio

Financial Instruments - Additional Information (Detail) - 6 months ended Jun. 30, 2018 ₺ in Millions	USD ($)Institution	TRY (₺)
Financial Statement Line Items With Differences In Reported Amount And Reporting Currency Denominated Amounts [Line Items]
Currency risk descriptions	We have underlying foreign currency exchange rate exposure. Our currency exposures primarily relate to transactions denominated in the Bulgarian Lev, the European Union Euro, and the New Turkish Lira (“TRY”). We are also subject to foreign currency exposures resulting from translating the functional currency of our subsidiary financial statements into the U.S. Dollar reporting currency. At June 30, 2018, we had 1.0 million TRY (approximately $0.2 million) in cash and cash equivalents, which exposes us to exchange rate risk based on fluctuations in the value of the TRY. We have not used foreign currency forward contracts to manage exchange rate fluctuations prior to 2018. At June 30, 2018, we were a party to foreign exchange derivative contracts (See Note 6. “Derivative instruments”).
Number of financial institutions | Institution	4
TUPRAS [Member]
Financial Statement Line Items With Differences In Reported Amount And Reporting Currency Denominated Amounts [Line Items]
Allowance for doubtful accounts | $	$ 0
Cash and cash equivalents [Member]
Financial Statement Line Items With Differences In Reported Amount And Reporting Currency Denominated Amounts [Line Items]
Cash and cash equivalents	$ 200,000	₺ 1

Financial Instruments - Valuati

Financial Instruments - Valuation of Financial Assets and Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (liabilities), fair value	$ (29,410)	$ (26,694)
Disclosed but not carried at fair value [Member] | 2018 Term Loan [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	(8,493)
Disclosed but not carried at fair value [Member] | 2017 Term Loan [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	(18,035)	(16,613)
Disclosed but not carried at fair value [Member] | 2016 Term Loan [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value		(7,866)
Measured on a recurring basis [Member] | Foreign Exchange Derivative Contracts [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	(1,324)
Measured on a recurring basis [Member] | Derivative Financial Instruments (commodity) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	(1,558)	(2,215)
Significant Other Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (liabilities), fair value	(2,882)	(2,215)
Significant Other Observable Inputs (Level 2) [Member] | Measured on a recurring basis [Member] | Foreign Exchange Derivative Contracts [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	(1,324)
Significant Other Observable Inputs (Level 2) [Member] | Measured on a recurring basis [Member] | Derivative Financial Instruments (commodity) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	(1,558)	(2,215)
Significant Unobservable Inputs (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (liabilities), fair value	(26,528)	(24,479)
Significant Unobservable Inputs (Level 3) [Member] | Disclosed but not carried at fair value [Member] | 2018 Term Loan [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	(8,493)
Significant Unobservable Inputs (Level 3) [Member] | Disclosed but not carried at fair value [Member] | 2017 Term Loan [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	$ (18,035)	(16,613)
Significant Unobservable Inputs (Level 3) [Member] | Disclosed but not carried at fair value [Member] | 2016 Term Loan [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value		$ (7,866)

Related Party Transactions - Re

Related Party Transactions - Related Party Accounts Receivable and Accounts Payable (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Total related party accounts receivable	$ 1,153	$ 1,023
Total related party accounts payable	3,388	3,141
Riata Management Service Agreement [Member]
Related Party Transaction [Line Items]
Total related party accounts receivable	704	576
Total related party accounts payable	672	341
PSIL MSA [Member]
Related Party Transaction [Line Items]
Total related party accounts receivable	449	447
Total related party accounts payable	2,213	2,119
Other - Board of Directors Fees [Member]
Related Party Transaction [Line Items]
Total related party accounts payable	125
Interest payable on Series A Preferred [Member]
Related Party Transaction [Line Items]
Total related party accounts payable	$ 378	$ 681

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail)	Nov. 04, 2016shares	Apr. 19, 2016USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Jun. 14, 2018ft²	Dec. 31, 2017USD ($)	Aug. 31, 2016USD ($)	Jun. 30, 2016shares	Jun. 13, 2012USD ($)
Related Party Transaction [Line Items]
Related parties outstanding receivables			$ 1,153,000	$ 1,153,000		$ 1,023,000
Related parties outstanding payables			3,388,000	3,388,000		3,141,000
Note receivable - related party			6,287,000	6,287,000		6,726,000			$ 11,500,000
Dalea and Funds [Member] | 2017 Notes [Member]
Related Party Transaction [Line Items]
Payment of common shares | shares								201,459
Interest receivable			6,300,000	6,300,000
Dalea and Funds [Member] | 2017 Notes [Member] | Series A Preferred Stock [Member]
Related Party Transaction [Line Items]
Repayments of debt			$ 100,000	$ 100,000
Mitchell and his wife [Member] | Riata Management [Member]
Related Party Transaction [Line Items]
Percentage of ownership interest owned by related party			100.00%	100.00%
Riata Management Service Agreement [Member]
Related Party Transaction [Line Items]
Related parties outstanding receivables			$ 704,000	$ 704,000		576,000
Related parties outstanding payables			$ 672,000	$ 672,000		341,000
Mitchell and Family [Member] | Longfellow [Member]
Related Party Transaction [Line Items]
Percentage of ownership interest owned by related party			100.00%	100.00%
MedOil Supply, LLC [Member] | Riata Management [Member]
Related Party Transaction [Line Items]
Percentage of ownership interest owned by related party			100.00%	100.00%
Dalea [Member] | Viking Drilling [Member]
Related Party Transaction [Line Items]
Percentage of ownership interest owned by related party			100.00%	100.00%
PSIL MSA [Member]
Related Party Transaction [Line Items]
Related parties outstanding receivables			$ 449,000	$ 449,000		447,000
Related parties outstanding payables			2,213,000	$ 2,213,000		$ 2,119,000
Longfellow [Member] | TransAtlantic USA [Member]
Related Party Transaction [Line Items]
Office sub lease space | ft²					10,000
Office sub lease commencement date				Jun. 14, 2018
Office sub Lease Expiration Date				Jun. 30, 2020
Office sub lease monthly rent payable during first twelve months			18,333.33	$ 18,333.33
Increase in office sub lease monthly rent payable from first year			416.67	$ 416.67
Increase in office sub lease monthly rent payable, commencement date				Jun. 30, 2019
Increase in office sub lease monthly rent payable, expiration date				Jun. 30, 2021
Joint Venture [Member] | Dalea and Funds [Member]
Related Party Transaction [Line Items]
Convertible preferred shares issued upon conversion | shares	40,000
Joint Venture [Member] | Dalea and Funds [Member] | Promissory Note [Member]
Related Party Transaction [Line Items]
Note receivable - related party		$ 7,964,053
Cancellation of purchase price in promissory note		$ 3,500,000
Debt instrument, maturity date		Jun. 13, 2019
Debt instrument interest rate stated percentage		3.00%
Promissory note, collateral amount		$ 2,000,000
Dalea Promissory Note [Member]
Related Party Transaction [Line Items]
Noncontrolling equity voting interest percentage		50.00%
Promissory notes default remedy period		30 days
Gundem Fee Agreement [Member] | Gundem Real Estate [Member]
Related Party Transaction [Line Items]
Debt instrument interest rate stated percentage							5.00%
Promissory note, collateral amount							$ 10,000,000
Gundem Fee Agreement [Member] | Muratli Real Estate [Member]
Related Party Transaction [Line Items]
Debt instrument interest rate stated percentage							5.00%
Promissory note, collateral amount							$ 5,000,000
Diyarbakir Fee Agreement [Member] | Diyarbakir Real Estate [Member]
Related Party Transaction [Line Items]
Debt instrument interest rate stated percentage							5.00%
Promissory note, collateral amount							$ 5,000,000
Gundem Fee Agreement and the Diyarbakir Fee Agreement [Member]
Related Party Transaction [Line Items]
Decrease in principal amount of Amended Note			$ 200,000	$ 300,000

Assets and Liabilities Held f58

Assets and Liabilities Held for Sale and Discontinued Operations - Additional Information (Detail) - USD ($)	Feb. 24, 2017	Jun. 30, 2018	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Discontinued Operations And Disposal Groups [Line Items]
Gross proceeds on sale of ownership interests						$ 17,779,000
Post closing purchase price adjustment	$ 200,000
Loss on sale of TBNG				$ 15,200,000
Operating results from discontinued operations		$ 0	$ 0		$ 0	$ 0
Thrace Basin Natural Gas (Turkiye) Corporation [Member]
Discontinued Operations And Disposal Groups [Line Items]
Gross proceeds on sale of ownership interests	20,700,000
Net cash proceeds on sale of ownership interests	$ 16,100,000
Assets held for sale		0			0		$ 0
Liabilities held for sale		$ 0			$ 0		$ 0

Assets and Liabilities Held f59

Assets and Liabilities Held for Sale and Discontinued Operations - Reclassification of Accumulated Foreign Currency Translation Adjustment Realized Into Earnings from Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2017	Jun. 30, 2018	Jun. 30, 2017
Discontinued Operations And Disposal Groups [Line Items]
Gross proceeds on sale of ownership interests			$ 17,779
Net loss on sale of TBNG	$ (15,200)
Thrace Basin Natural Gas (Turkiye) Corporation [Member]
Discontinued Operations And Disposal Groups [Line Items]
Gross proceeds on sale of ownership interests		$ 20,707
Less: TBNG net assets		12,869
Gain on sale before accumulated foreign currency translation adjustment		7,838
Less: TBNG accumulated foreign currency translation adjustment		(23,064)
Net loss on sale of TBNG		$ (15,226)

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2018
Longfellow [Member] | TransAtlantic USA [Member]
Subsequent Event [Line Items]
Office sub lease effective date	Jun. 14, 2018