Gran Tierra Energy (GTE) 10-Q 5 May 21 2021 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2021	Apr. 30, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	001-34018
Entity Registrant Name	GRAN TIERRA ENERGY INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	98-0479924
Entity Address, Address Line One	900, 520 - 3 Avenue SW
Entity Address, City or Town	Calgary,
Entity Address, State or Province	AB
Entity Address, Country	CA
Entity Address, Postal Zip Code	T2P 0R3
City Area Code	403
Local Phone Number	265-3221
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	GTE
Security Exchange Name	NYSEAMER
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		366,981,556
Entity Central Index Key	0001273441
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Amendment Flag	false

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Statement [Abstract]
OIL SALES (Note 8)	$ 95,493,000	$ 86,079,000
EXPENSES
Operating	29,625,000	44,588,000
Transportation	2,506,000	4,037,000
COVID-19 related costs (Note 9)	1,139,000	0
Depletion, depreciation and accretion	31,318,000	57,294,000
Goodwill impairment (Note 5)	0	102,581,000
Asset impairment (Note 5)	0	3,904,000
General and administrative	9,569,000	5,385,000
Severance	919,000	1,322,000
Foreign exchange loss	13,083,000	18,807,000
Derivative instruments loss (gain) (Note 12)	23,698,000	(12,867,000)
Other financial instruments (gain) loss (Note 12)	(1,405,000)	65,285,000
Interest expense (Note 6)	13,812,000	12,810,000
EXPENSES	124,264,000	303,146,000
INTEREST INCOME	0	345,000
LOSS BEFORE INCOME TAXES	(28,771,000)	(216,722,000)
INCOME TAX EXPENSE
Current (Note 10)	0	298,000
Deferred (Note 10)	8,651,000	34,606,000
INCOME TAX EXPENSE	8,651,000	34,904,000
NET AND COMPREHENSIVE LOSS	$ (37,422,000)	$ (251,626,000)
NET LOSS PER SHARE
BASIC (in dollars per share)	$ (0.10)	$ (0.69)
DILUTED (in dollars per share)	$ (0.10)	$ (0.69)
WEIGHTED AVERAGE SHARES OUTSTANDING - BASIC (Note 7) (in shares)	366,981,556	366,981,556
WEIGHTED AVERAGE SHARES OUTSTANDING - DILUTED (Note 7) (in shares)	366,981,556	366,981,556

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current Assets
Cash and cash equivalents (Note 13)	$ 21,649	$ 14,114
Accounts receivable	4,074	8,044
Investment (Note 12)	33,796	48,323
Taxes receivable (Note 3)	38,835	49,925
Other current assets	14,827	13,459
Total Current Assets	113,181	133,865
Oil and Gas Properties
Proved	812,328	797,355
Unproved	160,525	161,763
Total Oil and Gas Properties	972,853	959,118
Other capital assets	4,683	5,364
Total Property, Plant and Equipment (Note 4)	977,536	964,482
Other Long-Term Assets
Deferred tax assets	39,169	57,318
Taxes receivable (Note 3)	40,803	42,635
Restricted cash and cash equivalents (Note 13)	3,219	3,409
Other	856	16
Total Other Long-Term Assets	84,047	103,378
Total Assets	1,174,764	1,201,725
Current Liabilities
Accounts payable and accrued liabilities	99,386	100,784
Derivatives (Note 12)	26,398	12,050
Equity compensation award liability (Note 7 and 12)	1,671	805
Total Current Liabilities	127,455	113,639
Long-Term Liabilities
Long-term debt (Notes 6 and 12)	764,768	774,770
Asset retirement obligation	51,301	48,214
Equity compensation award liability (Note 7 and 12)	7,329	3,955
Other long-term liabilities	3,720	4,113
Total Long-Term Liabilities	827,118	831,052
Contingencies (Note 11)
Shareholders’ Equity
Common Stock (Note 7) (366,981,556 shares issued and outstanding of Common Stock, par value $0.001 per share, as at March 31, 2021, and December 31, 2020, respectively)	10,270	10,270
Additional paid-in capital	1,285,597	1,285,018
Deficit	(1,075,676)	(1,038,254)
Total Shareholders’ Equity	220,191	257,034
Total Liabilities and Shareholders’ Equity	$ 1,174,764	$ 1,201,725

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Common Stock, shares issued (in shares)	366,981,556	366,981,556
Common Stock, shares outstanding (in shares)	366,981,556	366,981,556
Common Stock, par value (in dollars per share)	$ 0.001	$ 0.001

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating Activities
Net loss	$ (37,422,000)	$ (251,626,000)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depletion, depreciation and accretion	31,318,000	57,294,000
Goodwill impairment (Note 5)	0	102,581,000
Asset impairment (Note 5)	0	3,904,000
Deferred tax expense	8,651,000	34,606,000
Stock-based compensation expense (recovery) (Note 7)	3,671,000	(2,055,000)
Amortization of debt issuance costs (Note 6)	881,000	844,000
Unrealized foreign exchange loss	13,003,000	20,799,000
Derivative instruments loss	23,698,000	(12,867,000)
Cash settlements on derivatives instruments	(13,404,000)	3,487,000
Other financial instruments (gain) loss (Note 12)	(1,405,000)	65,285,000
Cash settlement of asset retirement obligation	(169,000)	(27,000)
Non-cash lease expenses	444,000	490,000
Lease payments	(462,000)	(515,000)
Net change in assets and liabilities from operating activities (Note 13)	13,128,000	(16,702,000)
Net cash provided by operating activities	41,932,000	5,498,000
Investing Activities
Additions to property, plant and equipment	(37,427,000)	(44,277,000)
Proceeds on disposition of investment, net of transaction costs (Note 12)	14,632,000	0
Changes in non-cash investing working capital	(708,000)	(17,850,000)
Net cash used in investing activities (Note 13)	(23,503,000)	(62,127,000)
Financing Activities
Proceeds from debt, net of issuance costs (Note 6)	(125,000)	88,009,000
Repayment of debt (Note 6)	(10,000,000)	0
Lease payments	(513,000)	(243,000)
Net cash (used in) provided by financing activities	(10,638,000)	87,766,000
Foreign exchange loss on cash, cash equivalents and restricted cash and cash equivalents	(446,000)	(450,000)
Net increase in cash, cash equivalents and restricted cash and cash equivalents	7,345,000	30,687,000
Cash, cash equivalents and restricted cash and cash equivalents, beginning of period (Note 13)	17,523,000	11,075,000
Cash, cash equivalents and restricted cash and cash equivalents, end of period (Note 13)	$ 24,868,000	$ 41,762,000

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Share Capital	Additional Paid-in Capital	Deficit
Balance, beginning of period at Dec. 31, 2019		$ 10,270	$ 1,282,627	$ (260,287)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation (Note 7)			565
Net loss	$ (251,626)			(251,626)
Balance, end of period at Mar. 31, 2020	781,549	10,270	1,283,192	(511,913)
Balance, beginning of period at Dec. 31, 2020		10,270	1,285,018	(1,038,254)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation (Note 7)			579
Net loss	(37,422)			(37,422)
Balance, end of period at Mar. 31, 2021	$ 220,191	$ 10,270	$ 1,285,597	$ (1,075,676)

Description of Business

Description of Business	3 Months Ended
	Mar. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business Gran Tierra Energy Inc., a Delaware corporation (the “Company” or “Gran Tierra”), is a publicly traded company focused on international oil and natural gas exploration and production with assets currently in Colombia and Ecuador.

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies These interim unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”). The information furnished herein reflects all normal recurring adjustments that are, in the opinion of management, necessary for the fair presentation of results for the interim periods. The note disclosure requirements of annual consolidated financial statements provide additional disclosures to that required for interim unaudited condensed consolidated financial statements. Accordingly, these interim unaudited condensed consolidated financial statements should be read in conjunction with the Company’s consolidated financial statements as at and for the year ended December 31, 2020, included in the Company’s 2020 Annual Report on Form 10-K.

Taxes Receivable

Taxes Receivable	3 Months Ended
	Mar. 31, 2021
Tax Receivable Agreement [Abstract]
Taxes Receivable	Taxes Receivable The table below shows the break-down of taxes receivable, which are comprised of value added tax ("VAT") and income tax receivables: (Thousands of U.S. Dollars) As at March 31, 2021 As at December 31, 2020 Current VAT Receivable $ 27,130 $ 35,977 Income Tax Receivable 11,705 13,948 $ 38,835 $ 49,925 Long-Term VAT Receivable $ 21,377 $ 28,485 Income Tax Receivable 19,426 14,150 $ 40,803 $ 42,635 Total Taxes Receivable $ 79,638 $ 92,560 The following table shows the movement of VAT and income tax receivables for the period identified below: (Thousands of U.S. Dollars) VAT Receivable Income Tax Receivable Total Taxes Receivable Balance, as at December 31, 2020 $ 64,462 $ 28,098 $ 92,560 Collected through direct government refunds (270) — (270) Collected through sales contracts (19,771) — (19,771) Taxes paid (1) 8,044 6,093 14,137 Foreign exchange loss (3,958) (3,060) (7,018) Balance, as at March 31, 2021 $ 48,507 $ 31,131 $ 79,638 (1) VAT is paid on certain goods and services in Colombia at a rate of 19%

Property, Plant and Equipment

Property, Plant and Equipment	3 Months Ended
	Mar. 31, 2021
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant and Equipment (Thousands of U.S. Dollars) As at March 31, 2021 As at December 31, 2020 Oil and natural gas properties Proved $ 4,151,776 $ 4,106,768 Unproved 160,525 161,763 4,312,301 4,268,531 Other (1) 32,437 32,135 4,344,738 4,300,666 Accumulated depletion and depreciation and impairment (3,367,202) (3,336,184) $ 977,536 $ 964,482 (1) The "other" category includes right-of-use assets for operating and finance leases of $11.7 million, which had a net book value of $3.9 million as at March 31, 2021 (December 31, 2020 - $11.4 million which had a net book value of $4.4 million).

Impairment

Impairment	3 Months Ended
	Mar. 31, 2021
Impairment Disclosure [Abstract]
Impairment	Impairment Asset impairment (i) Oil and gas property impairment For each of the three months ended March 31, 2021 and 2020, Gran Tierra had no ceiling test impairment losses. The Company used an average Brent price of $43.31 and $67.49 per bbl, respectively, for the purposes of the March 31, 2021 and 2020, respectively, ceiling test calculations. (ii) Inventory impairment For the three months ended March 31, 2021 and 2020, the Company had nil, and $3.9 million, respectively, of inventory impairment. Goodwill impairment For the three months ended March 31, 2021, the Company had no goodwill impairment. The entire goodwill balance of $102.6 million was impaired during the three months ended March 31, 2020 due to the carrying value of the unit exceeding its fair value as a result of the impact of lower forecasted commodity prices.

Debt and Debt Issuance Costs

Debt and Debt Issuance Costs	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Debt and Debt Issuance Costs	Debt and Debt Issuance Costs The Company's debt at March 31, 2021 and December 31, 2020 was as follows: (Thousands of U.S. Dollars) As at March 31, 2021 As at December 31, 2020 6.25% Senior Notes $ 300,000 $ 300,000 7.75% Senior Notes 300,000 300,000 Revolving credit facility 180,000 190,000 Unamortized debt issuance costs (17,368) (18,124) Long-term debt 762,632 771,876 Long-term lease obligation (1) 2,136 2,894 $ 764,768 $ 774,770 (1) The current portion of the lease obligation has been included in accounts payable and accrued liabilities on the Company's balance sheet and totaled $3.1 million as at March 31, 2021 (December 31, 2020 - $3.3 million). As at March 31, 2021 the borrowing base of the Company's Senior Secured Credit Facility (the "revolving credit facility") was $215 million with the next re-determination to occur no later than May, 2021. The Company is required to comply with various covenants, which have been modified in response to the recent market conditions and the COVID-19 pandemic until October 1, 2021 ("the covenant relief period"). During the covenant relief period, the Company's ratio of total debt to Covenant EBITDAX ("EBITDAX") is permitted to be greater than 4.0 to 1.0, its Senior Secured Debt to EBITDAX ratio must not exceed 2.5 to 1.0, and its EBITDAX to interest expense ratio for the trailing four quarter periods measured as of the last day of the fiscal quarters ended (i) March 31, 2021, must be at least 1.5 to 1.0, (ii) June 30, 2021 to September 30, 2021 must be at least 2.0 to 1.0, and (iii) at least 2.5 to 1.0 thereafter. As of March 31, 2021, the Company was in compliance with all applicable covenants in the revolving credit facility. After the expiration of covenant relief period, the Company must maintain compliance with the following financial covenants: limitations on Company's ratio of debt to EBITDAX to a maximum of 4.0 to 1.0; limitations on Company's ratio of Senior Secured Debt to EBITDAX to a maximum of 3.0 to 1.0; and the maintenance of a ratio of EBITDAX to interest expense of at least 2.5 to 1.0. If the Company fails to comply with these financial covenants, it would result in a default under the terms of the credit agreement, which could result in an acceleration of repayment of all indebtedness under the Company's revolving credit facility. Amounts drawn down under the revolving credit facility bear interest, at the Company's option, at the USD LIBOR rate plus a margin ranging from 2.90% to 4.90%, or an alternate base rate plus a margin ranging from 1.90% to 3.90%, in each case based on the borrowing base utilization percentage. The alternate base rate is currently the U.S. prime rate. Undrawn amounts under the revolving credit facility bear interest from 0.73% to 1.23% per annum, based on the average daily amount of unused commitments. The Company’s revolving credit facility is guaranteed by and secured against the assets of certain of the Company’s subsidiaries (the "Credit Facility Group"). Under the terms of the credit facility, the Company is subject to certain restrictions on its ability to distribute funds to entities outside of the Credit Facility Group, including restrictions on the ability to pay dividends to shareholders of the Company. Interest Expense The following table presents total interest expense recognized in the accompanying interim unaudited condensed consolidated statements of operations: Three Months Ended March 31, (Thousands of U.S. Dollars) 2021 2020 Contractual interest and other financing expenses $ 12,931 $ 11,966 Amortization of debt issuance costs 881 844 $ 13,812 $ 12,810

Share Capital

Share Capital	3 Months Ended
	Mar. 31, 2021
Share-based Payment Arrangement [Abstract]
Share Capital	Share Capital Shares of Common Stock Balance at December 31, 2020 and March 31, 2021 366,981,556 Equity Compensation Awards The following table provides information about p erformance stock units (“PSUs”), deferred share units (“DSUs”), and stock option activity for the three months ended March 31, 2021: PSUs DSUs Stock Options Number of Outstanding Share Units Number of Outstanding Share Units Number of Outstanding Stock Options Weighted Average Exercise Price/Stock Option ($) Balance, December 31, 2020 23,273,404 4,067,897 15,444,949 1.50 Granted 13,153,840 722,073 5,563,441 0.81 Exercised (2,733,209) — — — Forfeited (1,828,743) — (884,211) 0.86 Expired — — (1,020,437) 3.27 Balance, March 31, 2021 31,865,292 4,789,970 19,103,742 1.24 Net Loss per Share Basic net loss per share is calculated by dividing net loss by the weighted average number of shares of Common Stock issued and outstanding during each period. Diluted net loss per share is calculated using the treasury stock method for share-based compensation arrangements. The treasury stock method assumes that any proceeds obtained on exercise of share-based compensation arrangements would be used to purchase common shares at the average market price during the period. The weighted average number of shares is then adjusted by the difference between the number of shares issued from the exercise of share-based compensation arrangements and shares repurchased from the related proceeds. Anti-dilutive shares represent potentially dilutive securities that are excluded from the computation of diluted income or loss per share as their impact would be anti-dilutive.

Revenue

Revenue	3 Months Ended
	Mar. 31, 2021
Revenue from Contract with Customer [Abstract]
Revenue	RevenueThe Company's revenues are generated from oil sales at prices which reflect the blended prices received upon shipment by the purchaser at defined sales points or are defined by contract relative to ICE Brent and adjusted for Vasconia or Castilla crude differentials, quality, and transportation discounts each period. For each of the three months ended March 31, 2021 and 2020, 100% of the Company's revenue resulted from oil sales. During the three months ended March 31, 2021, quality and transportation discounts were 15% of the average ICE Brent price (three months ended March 31, 2020 - 25%). During the three months ended March 31, 2021, the Company's production was sold primarily to two major customers in Colombia (three months ended March 31, 2020 - three) of which equaled 68% and 31%, respectively, of total sales volumes.As at March 31, 2021, accounts receivable included nil of accrued sales revenue related to March 2021 production (December 31, 2020 - $0.1 million related to December 31, 2020 production).

COVID-19 Costs

COVID-19 Costs	3 Months Ended
	Mar. 31, 2021
Unusual or Infrequent Items, or Both [Abstract]
COVID-19 Costs	COVID-19 CostsThe COVID-19 pandemic resulted in extra operating and transportation costs related to COVID-19 health and safety preventative measures including incremental sanitation requirements and enhanced procedures for trucking barrels and crew changes in the field. Below is a break-down of the costs: Three Months Ended March 31, (Thousands of U.S. Dollars) 2021 2020 Operating expenses $ 1,046 $ — Transportation costs 93 — Total COVID-19 costs $ 1,139 $ —

Taxes

Taxes	3 Months Ended
	Mar. 31, 2021
Income Tax Disclosure [Abstract]
Taxes	Taxes The Company's effective tax rate was (30)% for the three months ended March 31, 2021, compared to (16)% in the comparative period of 2020. Current income tax expense was nil for the three months ended March 31, 2021, compared to the corresponding period in 2020, primarily as a result of no taxable income resulting from the use of tax losses and the elimination of the minimum tax, in Colombia. The deferred income tax expense for the three months ended March 31, 2021, was the result of excess tax depreciation compared with accounting depreciation and the use of tax losses to offset taxable income in Colombia. The deferred income tax expense in the comparative period of 2020 was mainly the result of tax depreciation being higher than accounting depreciation in Colombia. For the three months ended March 31, 2021, the difference between the effective tax rate of (30)% and the 31% Colombian tax rate was primarily due to an increase in the impact of foreign taxes, foreign translation adjustments and other permanent differences, which was partially offset by a decrease in valuation allowance.

Contingencies

Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies Legal Proceedings Gran Tierra has a number of lawsuits and claims pending, including a dispute with the Agencia Nacional de Hidrocarburos (National Hydrocarbons Agency) ("ANH") relating to the calculation of high price share royalties. Discussions with the ANH are ongoing. Although the outcome of these lawsuits and disputes cannot be predicted with certainty, Gran Tierra believes the resolution of these matters would not have a material adverse effect on the Company’s consolidated financial position, results of operations or cash flows. Gran Tierra records costs as they are incurred or become probable and determinable. Letters of credit and other credit support At March 31, 2021, the Company had provided letters of credit and other credit support totaling $104.4 million (December 31, 2020 - $100.6 million) as security relating to work commitment guarantees in Colombia and Ecuador contained in exploration contracts and other capital or operating requirements.

Financial Instruments and Fair

Financial Instruments and Fair Value Measurement	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Financial Instruments and Fair Value Measurement	Financial Instruments and Fair Value Measurement Financial Instruments At March 31, 2021, the Company’s financial instruments recognized on the balance sheet consisted of: cash and cash equivalents, restricted cash and cash equivalents, accounts receivable, investment, other long-term assets, accounts payable and accrued liabilities, derivatives, equity compensation award liability, long-term debt and other long-term liabilities. Fair Value Measurement The fair value of investment, derivatives and equity compensation award liability is remeasured at the estimated fair value at the end of each reporting period. Investment in PetroTal The fair value of the Company's investment in PetroTal was estimated to be $33.8 million at March 31, 2021 ($48.3 million at December 31, 2020), based on the closing stock price of PetroTal of $0.31 CAD ($0.25 CAD at December 31, 2020) and the foreign exchange rate at that date. PetroTal is a publicly-traded energy company incorporated and domiciled in Canada engaged in exploration, appraisal and development of crude oil and natural gas in Peru. PetroTal's shares are listed on the Toronto Stock Exchange Venture under the trading symbol 'TAL' and on the London Stock Exchange Alternative Investment Market under the trading symbol 'PTAL'. Gran Tierra through a subsidiary holds approximately 137 million common shares representing approximately 17% of PetroTal's issued and outstanding common shares. Gran Tierra has the right to nominate two directors to the board of PetroTal. During three months ended March 31, 2021, the Company sold 44% (109 million common shares) of its interest in PetroTal for cash proceeds net of transaction costs of $14.6 million resulting in a loss on sale of $5.1 million. Commodity and Foreign Currency Derivatives The fair value of commodity price and foreign currency derivatives is estimated based on various factors, including quoted market prices in active markets and quotes from third parties. The Company also performs an internal valuation to ensure the reasonableness of third party quotes. In consideration of counterparty credit risk, the Company assessed the possibility of whether the counterparty to the derivative would default by failing to make any contractually required payments. Additionally, the Company considers that it is of substantial credit quality and has the financial resources and willingness to meet its potential repayment obligations associated with the derivative transactions. PSUs and DSUs The fair value of the PSUs liability was estimated based on a pricing model using inputs such as quoted market prices in an active market, and PSUs performance factor. The fair value of DSUs liability is measured using quoted market prices in an active market. The fair value of investment, derivatives and PSUs and DSUs liability at March 31, 2021, and December 31, 2020, was as follows: (Thousands of U.S. Dollars) As at March 31, 2021 As at December 31, 2020 Investment $ 33,796 $ 48,323 Derivative liability $ 26,398 $ 12,050 PSUs and DSUs liability 9,000 4,760 $ 35,398 $ 16,810 The following table presents gains or losses on derivative and other financial instruments recognized in the accompanying interim unaudited condensed consolidated statements of operations: Three Months Ended March 31, (Thousands of U.S. Dollars) 2021 2020 Commodity price derivatives loss (gain) $ 23,632 $ (18,319) Foreign currency derivatives loss 66 5,452 Derivative instruments loss (gain) $ 23,698 $ (12,867) Unrealized PetroTal investment (gain) loss $ (6,475) $ 65,285 Loss on sale of PetroTal shares 5,070 — Other financial instruments (gain) loss $ (1,405) $ 65,285 Financial instruments not recorded at fair value include the Company's 6.25% Senior Notes due 2025 (the "6.25% Senior Notes") and 7.75% Senior Notes due 2027 (the "7.75% Senior Notes"). At March 31, 2021, the carrying amounts of the 6.25% Senior Notes and the 7.75% Senior Notes were $292.7 million and $291.2 million, respectively, which represented the aggregate principal amount less unamortized debt issuance costs, and the fair values were $248.3 million and $243.5 million, respectively. The fair value of long-term restricted cash and cash equivalents and the revolving credit facility approximated their carrying value because interest rates are variable and reflective of market rates. The fair values of other financial instruments approximate their carrying amounts due to the short-term maturity of these instruments. GAAP establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. This hierarchy consists of three broad levels. Level 1 inputs consist of quoted prices (unadjusted) in active markets for identical assets and liabilities and have the highest priority. Level 2 and 3 inputs are based on significant other observable inputs and significant unobservable inputs, respectively, and have lower priorities. The Company uses appropriate valuation techniques based on the available inputs to measure the fair values of assets and liabilities. At March 31, 2021, the fair value of the investment and DSUs liability was determined using Level 1 inputs, and the fair value of the derivative and PSUs liability was determined using Level 2 inputs. The Company uses available market data and valuation methodologies to estimate the fair value of debt. The fair value of debt is the estimated amount the Company would have to pay a third party to assume the debt, including a credit spread for the difference between the issue rate and the period end market rate. The credit spread is the Company’s default or repayment risk. The credit spread (premium or discount) is determined by comparing the Company’s Senior Notes and revolving credit facility to new issuances (secured and unsecured) and secondary trades of similar size and credit statistics for both public and private debt. The disclosure in the paragraph above regarding the fair value of cash and restricted cash and cash equivalents and Senior Notes was based on Level 1 inputs and the fair value of credit facility was based on Level 2 inputs. The Company’s non-recurring fair value measurements include asset retirement obligations. The fair value of an asset retirement obligation is measured by reference to the expected future cash outflows required to satisfy the retirement obligation discounted at the Company’s credit-adjusted risk-free interest rate. Commodity Price Derivatives The Company utilizes commodity price derivatives to manage the variability in cash flows associated with the forecasted sale of its oil production, reduce commodity price risk and provide a base level of cash flow in order to assure it can execute at least a portion of its planned capital spending. At March 31, 2021, the Company had outstanding commodity price derivative positions as follows: Period and type of instrument Volume, Reference Sold Put ($/bbl, Weighted Average) Purchased Put ($/bbl, Weighted Average) Sold Call ($/bbl, Weighted Average) Premium ($/bbl, Weighted Average) Three-way Collars: April 1, to June 30, 2021 14,000 ICE Brent 36.43 45.14 51.45 0.21 Collars: April 1, to June 30, 2021 1,000 ICE Brent n/a 45.00 50.40 n/a Three-way Collars: July 1, to December 31, 2021 4,000 ICE Brent 45.00 55.00 68.00 n/a Swaptions: July 1, to December 31, 2021 3,000 ICE Brent n/a n/a 56.75 n/a Subsequent to quarter end, the Company entered into the following commodity price derivative positions: Period and type of instrument Volume, Reference Sold Put ($/bbl, Weighted Average) Purchased Put ($/bbl, Weighted Average) Sold Call ($/bbl, Weighted Average) Premium ($/bbl, Weighted Average) Three-way Collars: July 1, to December 31, 2021 3,000 ICE Brent 50.00 60.00 70.21 n/a Foreign Currency Derivatives The Company utilizes foreign currency derivatives to manage the variability in cash flows associated with the Company's forecasted Colombian peso ("COP") denominated expenses. At March 31, 2021, the Company had outstanding foreign currency derivative positions as follows: Period and type of instrument Amount Hedged U.S. Dollar Equivalent of Amount Hedged (Thousands of U.S. Dollars) (1) Reference Floor Price Cap Price (COP, Weighted Average) Collars: April 1, to December 31, 2021 9,000,000 2,408 COP 3,500 3,630 (1) At March 31, 2021 foreign exchange rate.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	3 Months Ended
	Mar. 31, 2021
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	Supplemental Cash Flow Information The following table provides a reconciliation of cash and cash equivalents and restricted cash and cash equivalents with the Company's interim unaudited condensed consolidated balance sheet that sum to the total of these amounts shown in the interim unaudited condensed consolidated statements of cash flows: (Thousands of U.S. Dollars) As at March 31, As at December 31, 2021 2020 2020 2019 Cash and cash equivalents $ 21,649 $ 39,767 $ 14,114 $ 8,817 Restricted cash and cash equivalents - 3,219 1,995 3,409 2,258 $ 24,868 $ 41,762 $ 17,523 $ 11,075 Net changes in assets and liabilities from operating activities were as follows: Three Months Ended March 31, (Thousands of U.S. Dollars) 2021 2020 Accounts receivable and other long-term assets $ 3,803 $ 29,577 Derivatives 3,841 (3,873) Inventory (1,146) (1,473) Prepaids 157 15 Accounts payable and accrued and other long-term liabilities 752 (32,283) Taxes receivable and payable 5,721 (8,665) Net changes in assets and liabilities from operating activities $ 13,128 $ (16,702) Changes in non-cash investing working capital for the three months ended March 31, 2021 are comprised of a decrease in accounts payable and accrued liabilities of $0.8 million and a decrease in accounts receivable of $0.1 million (three months ended March 31, 2020, a decrease in accounts payable and accrued liabilities of $19.0 million and a decrease in accounts receivable of $1.2 million). The following table provides additional supplemental cash flow disclosures: Three Months Ended March 31, (Thousands of U.S. Dollars) 2021 2020 Cash paid for income taxes $ 5,034 $ 5,208 Cash paid for interest $ 11,479 $ 10,752 Non-cash investing activities: Net liabilities related to property, plant and equipment, end of period $ 28,003 $ 59,503

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	These interim unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”). The information furnished herein reflects all normal recurring adjustments that are, in the opinion of management, necessary for the fair presentation of results for the interim periods.

Taxes Receivable (Tables)

Taxes Receivable (Tables)	3 Months Ended
	Mar. 31, 2021
Tax Receivable Agreement [Abstract]
Schedule of Taxes Receivable Components	The table below shows the break-down of taxes receivable, which are comprised of value added tax ("VAT") and income tax receivables: (Thousands of U.S. Dollars) As at March 31, 2021 As at December 31, 2020 Current VAT Receivable $ 27,130 $ 35,977 Income Tax Receivable 11,705 13,948 $ 38,835 $ 49,925 Long-Term VAT Receivable $ 21,377 $ 28,485 Income Tax Receivable 19,426 14,150 $ 40,803 $ 42,635 Total Taxes Receivable $ 79,638 $ 92,560
Schedule of Taxes Receivable Roll Forward	The following table shows the movement of VAT and income tax receivables for the period identified below: (Thousands of U.S. Dollars) VAT Receivable Income Tax Receivable Total Taxes Receivable Balance, as at December 31, 2020 $ 64,462 $ 28,098 $ 92,560 Collected through direct government refunds (270) — (270) Collected through sales contracts (19,771) — (19,771) Taxes paid (1) 8,044 6,093 14,137 Foreign exchange loss (3,958) (3,060) (7,018) Balance, as at March 31, 2021 $ 48,507 $ 31,131 $ 79,638 (1) VAT is paid on certain goods and services in Colombia at a rate of 19%

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	3 Months Ended
	Mar. 31, 2021
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	(Thousands of U.S. Dollars) As at March 31, 2021 As at December 31, 2020 Oil and natural gas properties Proved $ 4,151,776 $ 4,106,768 Unproved 160,525 161,763 4,312,301 4,268,531 Other (1) 32,437 32,135 4,344,738 4,300,666 Accumulated depletion and depreciation and impairment (3,367,202) (3,336,184) $ 977,536 $ 964,482 (1) The "other" category includes right-of-use assets for operating and finance leases of $11.7 million, which had a net book value of $3.9 million as at March 31, 2021 (December 31, 2020 - $11.4 million which had a net book value of $4.4 million).

Debt and Debt Issuance Costs (T

Debt and Debt Issuance Costs (Tables)	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Schedule of Debt	The Company's debt at March 31, 2021 and December 31, 2020 was as follows: (Thousands of U.S. Dollars) As at March 31, 2021 As at December 31, 2020 6.25% Senior Notes $ 300,000 $ 300,000 7.75% Senior Notes 300,000 300,000 Revolving credit facility 180,000 190,000 Unamortized debt issuance costs (17,368) (18,124) Long-term debt 762,632 771,876 Long-term lease obligation (1) 2,136 2,894 $ 764,768 $ 774,770 (1) The current portion of the lease obligation has been included in accounts payable and accrued liabilities on the Company's balance sheet and totaled $3.1 million as at March 31, 2021 (December 31, 2020 - $3.3 million).
Schedule of Interest Expense Recognized	The following table presents total interest expense recognized in the accompanying interim unaudited condensed consolidated statements of operations: Three Months Ended March 31, (Thousands of U.S. Dollars) 2021 2020 Contractual interest and other financing expenses $ 12,931 $ 11,966 Amortization of debt issuance costs 881 844 $ 13,812 $ 12,810

Share Capital (Tables)

Share Capital (Tables)	3 Months Ended
	Mar. 31, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Common Stock	Shares of Common Stock Balance at December 31, 2020 and March 31, 2021 366,981,556
Schedule of PSU, DSU, RSU and Stock Option Activity	The following table provides information about p erformance stock units (“PSUs”), deferred share units (“DSUs”), and stock option activity for the three months ended March 31, 2021: PSUs DSUs Stock Options Number of Outstanding Share Units Number of Outstanding Share Units Number of Outstanding Stock Options Weighted Average Exercise Price/Stock Option ($) Balance, December 31, 2020 23,273,404 4,067,897 15,444,949 1.50 Granted 13,153,840 722,073 5,563,441 0.81 Exercised (2,733,209) — — — Forfeited (1,828,743) — (884,211) 0.86 Expired — — (1,020,437) 3.27 Balance, March 31, 2021 31,865,292 4,789,970 19,103,742 1.24

COVID-19 Costs (Tables)

COVID-19 Costs (Tables)	3 Months Ended
	Mar. 31, 2021
Unusual or Infrequent Items, or Both [Abstract]
Schedule Cost Incurred due to Catastrophic Events	The COVID-19 pandemic resulted in extra operating and transportation costs related to COVID-19 health and safety preventative measures including incremental sanitation requirements and enhanced procedures for trucking barrels and crew changes in the field. Below is a break-down of the costs: Three Months Ended March 31, (Thousands of U.S. Dollars) 2021 2020 Operating expenses $ 1,046 $ — Transportation costs 93 — Total COVID-19 costs $ 1,139 $ —

Financial Instruments and Fai_2

Financial Instruments and Fair Value Measurement (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Derivatives and RSU, PSU and DSU Liabilities	The fair value of investment, derivatives and PSUs and DSUs liability at March 31, 2021, and December 31, 2020, was as follows: (Thousands of U.S. Dollars) As at March 31, 2021 As at December 31, 2020 Investment $ 33,796 $ 48,323 Derivative liability $ 26,398 $ 12,050 PSUs and DSUs liability 9,000 4,760 $ 35,398 $ 16,810
Schedule of Gains or Losses on Financial Instruments Recognized	The following table presents gains or losses on derivative and other financial instruments recognized in the accompanying interim unaudited condensed consolidated statements of operations: Three Months Ended March 31, (Thousands of U.S. Dollars) 2021 2020 Commodity price derivatives loss (gain) $ 23,632 $ (18,319) Foreign currency derivatives loss 66 5,452 Derivative instruments loss (gain) $ 23,698 $ (12,867) Unrealized PetroTal investment (gain) loss $ (6,475) $ 65,285 Loss on sale of PetroTal shares 5,070 — Other financial instruments (gain) loss $ (1,405) $ 65,285
Schedule of Commodity Price Derivative Positions and Commodity Foreign Currency Contracts	At March 31, 2021, the Company had outstanding commodity price derivative positions as follows: Period and type of instrument Volume, Reference Sold Put ($/bbl, Weighted Average) Purchased Put ($/bbl, Weighted Average) Sold Call ($/bbl, Weighted Average) Premium ($/bbl, Weighted Average) Three-way Collars: April 1, to June 30, 2021 14,000 ICE Brent 36.43 45.14 51.45 0.21 Collars: April 1, to June 30, 2021 1,000 ICE Brent n/a 45.00 50.40 n/a Three-way Collars: July 1, to December 31, 2021 4,000 ICE Brent 45.00 55.00 68.00 n/a Swaptions: July 1, to December 31, 2021 3,000 ICE Brent n/a n/a 56.75 n/a Subsequent to quarter end, the Company entered into the following commodity price derivative positions: Period and type of instrument Volume, Reference Sold Put ($/bbl, Weighted Average) Purchased Put ($/bbl, Weighted Average) Sold Call ($/bbl, Weighted Average) Premium ($/bbl, Weighted Average) Three-way Collars: July 1, to December 31, 2021 3,000 ICE Brent 50.00 60.00 70.21 n/a
Schedule of Outstanding Foreign Currency Derivative Positions	At March 31, 2021, the Company had outstanding foreign currency derivative positions as follows: Period and type of instrument Amount Hedged U.S. Dollar Equivalent of Amount Hedged (Thousands of U.S. Dollars) (1) Reference Floor Price Cap Price (COP, Weighted Average) Collars: April 1, to December 31, 2021 9,000,000 2,408 COP 3,500 3,630 (1) At March 31, 2021 foreign exchange rate.

Supplemental Cash Flow Inform_2

Supplemental Cash Flow Information (Tables)	3 Months Ended
	Mar. 31, 2021
Supplemental Cash Flow Elements [Abstract]
Reconciliation of Cash, Cash Equivalents and Restricted Cash and Cash Equivalents	The following table provides a reconciliation of cash and cash equivalents and restricted cash and cash equivalents with the Company's interim unaudited condensed consolidated balance sheet that sum to the total of these amounts shown in the interim unaudited condensed consolidated statements of cash flows: (Thousands of U.S. Dollars) As at March 31, As at December 31, 2021 2020 2020 2019 Cash and cash equivalents $ 21,649 $ 39,767 $ 14,114 $ 8,817 Restricted cash and cash equivalents - 3,219 1,995 3,409 2,258 $ 24,868 $ 41,762 $ 17,523 $ 11,075
Schedule of Net Changes in Assets and Liabilities	Net changes in assets and liabilities from operating activities were as follows: Three Months Ended March 31, (Thousands of U.S. Dollars) 2021 2020 Accounts receivable and other long-term assets $ 3,803 $ 29,577 Derivatives 3,841 (3,873) Inventory (1,146) (1,473) Prepaids 157 15 Accounts payable and accrued and other long-term liabilities 752 (32,283) Taxes receivable and payable 5,721 (8,665) Net changes in assets and liabilities from operating activities $ 13,128 $ (16,702)
Schedule of Additional Supplemental Cash Flow Disclosures	The following table provides additional supplemental cash flow disclosures: Three Months Ended March 31, (Thousands of U.S. Dollars) 2021 2020 Cash paid for income taxes $ 5,034 $ 5,208 Cash paid for interest $ 11,479 $ 10,752 Non-cash investing activities: Net liabilities related to property, plant and equipment, end of period $ 28,003 $ 59,503

Taxes Receivable (Details)

Taxes Receivable (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Current
VAT Receivable		$ 27,130	$ 35,977
Income Tax Receivable		11,705	13,948
Tax Receivable		38,835	49,925
Long-Term
VAT Receivable		21,377	28,485
Income Tax Receivable		19,426	14,150
Tax Receivable		40,803	42,635
Total Taxes Receivable	$ 92,560	$ 79,638	$ 92,560
VAT Receivable
Beginning balance	64,462
Collected through direct government refunds	(270)
Collected through sales contracts	(19,771)
Taxes paid	8,044
Foreign exchange loss	(3,958)
Ending Balance	48,507
Income Tax Receivable
Beginning balance	28,098
Collected through direct government refunds	0
Collected through sales contracts	0
Taxes paid	6,093
Foreign exchange loss	(3,060)
Ending balance	31,131
Total Taxes Receivable
Beginning balance	92,560
Collected through direct government refunds	(270)
Collected through sales contracts	(19,771)
Taxes paid	14,137
Foreign exchange loss	(7,018)
Ending balance	$ 79,638
Colombia
Taxes Receivable [Line Items]
Value added tax, percent	19.00%

Property, Plant and Equipment_2

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 4,344,738	$ 4,300,666
Accumulated depletion and depreciation and impairment	(3,367,202)	(3,336,184)
Total Property, Plant and Equipment (Notes 5)	977,536	964,482
Right-of-use asset, gross	11,700	11,400
Right-of-use asset, net	3,900	4,400
Oil and natural gas properties
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	4,312,301	4,268,531
Proved
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	4,151,776	4,106,768
Unproved
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	160,525	161,763
Other
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 32,437	$ 32,135

Impairment (Details)

Impairment (Details)	3 Months Ended
	Mar. 31, 2021USD ($)$ / bbl	Mar. 31, 2020USD ($)$ / bbl
Property, Plant and Equipment [Line Items]
Impairment of oil and gas properties	$ 0
Inventory impairment	0	$ 3,900,000
Goodwill impairment	$ 0	$ 102,581,000
Crude Oil and NGL
Property, Plant and Equipment [Line Items]
Average Brent price per barrel (in USD per barrel) | $ / bbl	43.31	67.49

Debt and Debt Issuance Costs -

Debt and Debt Issuance Costs - Schedule of Debt (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ (17,368,000)	$ (18,124,000)
Long-term debt	762,632,000	771,876,000
Long-term lease obligation	2,136,000	2,894,000
Long-term debt excluding current maturity	$ 764,768,000	774,770,000
Senior notes | 6.25% Senior Notes
Debt Instrument [Line Items]
Stated interest rate	6.25%
Convertible senior notes and revolving credit facility	$ 300,000,000	300,000,000
Senior notes | 7.75% Senior Notes
Debt Instrument [Line Items]
Stated interest rate	7.75%
Convertible senior notes and revolving credit facility	$ 300,000,000	300,000,000
Revolving credit facility | Revolving credit facility
Debt Instrument [Line Items]
Convertible senior notes and revolving credit facility	180,000,000	190,000,000
Lease obligations | Accounts payable
Debt Instrument [Line Items]
Current portion of lease obligation	$ 3,100,000	$ 3,300,000

Debt and Debt Issuance Costs _2

Debt and Debt Issuance Costs - Narrative (Details) - Revolving credit facility - Revolving credit facility - USD ($)	3 Months Ended
	Mar. 31, 2021	Oct. 01, 2021	Jun. 01, 2020
Line of Credit Facility [Line Items]
Borrowing base	$ 215,000,000
Minimum
Line of Credit Facility [Line Items]
Debt to EBITDAX ratio			400.00%
EBITDAX to interest expense, ratio, current quarter	150.00%
EBITDAX to interest expense, ratio, next period	200.00%
EBITDAX to interest expense, ratio, thereafter	250.00%
Unused capacity, commitment fee percentage	0.73%
Minimum | LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.90%
Minimum | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.90%
Minimum | Forecast
Line of Credit Facility [Line Items]
EBITDAX to interest expense, ratio		250.00%
Maximum
Line of Credit Facility [Line Items]
Senior secured debt to EBITDAX ratio			250.00%
Unused capacity, commitment fee percentage	1.23%
Maximum | LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable rate	4.90%
Maximum | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	3.90%
Maximum | Forecast
Line of Credit Facility [Line Items]
Debt to EBITDAX ratio		400.00%
Senior secured debt to EBITDAX ratio		300.00%

Debt and Debt Issuance Costs _3

Debt and Debt Issuance Costs - Schedule of Interest Expense Recognized (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Debt Disclosure [Abstract]
Contractual interest and other financing expenses	$ 12,931	$ 11,966
Amortization of debt issuance costs	881	844
Total interest expense recognized	$ 13,812	$ 12,810

Share Capital - Schedule of Com

Share Capital - Schedule of Common Stock (Details) - shares	Mar. 31, 2021	Dec. 31, 2020
Increase (Decrease) in Common Stock
Common Stock, shares outstanding (in shares)	366,981,556	366,981,556
Shares of Common Stock
Increase (Decrease) in Common Stock
Common Stock, shares outstanding (in shares)	366,981,556	366,981,556

Share Capital - Schedule of PSU

Share Capital - Schedule of PSU, DSU, RSU and Stock Option Activity (Details)	3 Months Ended
	Mar. 31, 2021$ / sharesshares
Number of Outstanding Stock Options
Beginning Balance (in shares)	15,444,949
Granted (in shares)	5,563,441
Exercised (in shares)	0
Forfeited (in shares)	(884,211)
Expired (in shares)	(1,020,437)
Ending Balance (in shares)	19,103,742
Weighted Average Exercise Price/Stock Option ($)
Beginning balance (in dollars per share) | $ / shares	$ 1.50
Granted (in dollars per share) | $ / shares	0.81
Exercised (in dollars per share) | $ / shares	0
Forfeited (in dollars per share) | $ / shares	0.86
Expired (in dollars per share) | $ / shares	3.27
Ending balance (in dollars per share) | $ / shares	$ 1.24
PSUs
Number of Outstanding Share Units
Beginning Balance (in shares)	23,273,404
Granted (in shares)	13,153,840
Exercised (in shares)	(2,733,209)
Forfeited (in shares)	(1,828,743)
Expired (in shares)	0
Ending Balance (in shares)	31,865,292
DSUs
Number of Outstanding Share Units
Beginning Balance (in shares)	4,067,897
Granted (in shares)	722,073
Exercised (in shares)	0
Forfeited (in shares)	0
Expired (in shares)	0
Ending Balance (in shares)	4,789,970

Share Capital - Equity Compensa

Share Capital - Equity Compensation Awards (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 3.7	$ 2.1
Unrecognized compensation cost	$ 18.8		$ 5.9
Weighted average period for recognition	2 years 2 months 12 days
PSUs | Vested on December 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payments for units vested in period	$ 0.6
PSUs | Vested on December 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payments for units vested in period		$ 3.2

Share Capital - Weighted Averag

Share Capital - Weighted Average Shares Outstanding (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
Weighted average number of common shares outstanding, basic (in shares)	366,981,556	366,981,556
Weighted average number of common shares outstanding, diluted (in shares)	366,981,556	366,981,556

Revenue (Details)

Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Concentration Risk [Line Items]
Variable adjustment for transportation, location, quality, and other elements, percentage	(15.00%)	(25.00%)
Accrued sales revenue	$ 0		$ 0.1
Product Concentration Risk | Revenue from Contract with Customer
Concentration Risk [Line Items]
Concentration risk, percentage	100.00%
Product Concentration Risk | Revenue from Contract with Customer | Customer 1 | Colombia
Concentration Risk [Line Items]
Concentration risk, percentage		68.00%
Product Concentration Risk | Revenue from Contract with Customer | Customer 2 | Colombia
Concentration Risk [Line Items]
Concentration risk, percentage		31.00%

COVID-19 Costs (Details)

COVID-19 Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Unusual or Infrequent Items, or Both [Abstract]
Operating expenses	$ 1,046	$ 0
Transportation costs	93	0
Total COVID-19 costs	$ 1,139	$ 0

Taxes (Details)

Taxes (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Tax Contingency [Line Items]
Effective tax rate	(30.00%)	(16.00%)
Current income tax expense	$ 0	$ 298,000
Taxable income	$ (37,422,000)	$ (251,626,000)
PetroTal
Income Tax Contingency [Line Items]
Goodwill, nondeductible amount, percent	50.00%
Colombia
Income Tax Contingency [Line Items]
Taxable income	$ 0
Statutory income tax rate	31.00%	32.00%

Contingencies (Details)

Contingencies (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Letters of credit and other credit support provided	$ 104.4	$ 100.6

Financial Instruments and Fai_3

Financial Instruments and Fair Value Measurement - Narrative (Details) $ in Thousands, shares in Millions	3 Months Ended
	Mar. 31, 2021USD ($)shares	Mar. 31, 2020USD ($)	Mar. 31, 2021$ / shares	Dec. 31, 2020USD ($)	Dec. 31, 2020$ / shares
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value	$ 33,796			$ 48,323
Proceeds on disposition of investment	14,632	$ 0
Unrealized PetroTal investment (gain) loss	$ (6,475)	65,285
Senior notes | 6.25% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate	6.25%
Senior notes | 7.75% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate	7.75%
Fair value | Senior notes | 6.25% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, fair value disclosure	$ 248,300
Fair value | Senior notes | 7.75% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, fair value disclosure	243,500
Carrying amount | Senior notes | 6.25% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, fair value disclosure	292,700
Carrying amount | Senior notes | 7.75% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, fair value disclosure	291,200
PetroTal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value	$ 33,800
Closing share price (in dollars per share) | $ / shares			$ 0.31		$ 0.25
PetroTal | Fair value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment owned, balance (in shares) | shares	137
Investment owned, percent of total shares	17.00%
Petro Tal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of shares disposed, percent	44.00%
Number of shares disposed (in shares) | shares	109
Proceeds on disposition of investment	$ 14,600
Loss on disposition of stock	$ 5,100	$ 0

Financial Instruments and Fai_4

Financial Instruments and Fair Value Measurement - Schedule of Fair Value of Derivatives and RSU, PSU and DSU Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Investment	$ 33,796	$ 48,323
Derivative liability	26,398	12,050
PSU and DSU liability	9,000	4,760
Liabilities, fair value disclosure	$ 35,398	$ 16,810

Financial Instruments and Fai_5

Financial Instruments and Fair Value Measurement - Schedule of Gains or Losses on Financial Instruments Recognized (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments loss (gain)	$ 23,698	$ (12,867)
Unrealized PetroTal investment (gain) loss	(6,475)	65,285
Loss on sale of PetroTal shares	5,070	0
Other financial instruments (gain) loss	(1,405)	65,285
Commodity price derivatives loss (gain)
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments loss (gain)	23,632	(18,319)
Foreign currency derivatives loss
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments loss (gain)	$ 66	$ 5,452

Financial Instruments and Fai_6

Financial Instruments and Fair Value Measurement - Schedule of Commodity Price Derivative Positions and Commodity Foreign Currency Contracts (Details) - Forecast - Commodity Hedge	3 Months Ended	6 Months Ended
	Jun. 30, 2021$ / bblbbl	Dec. 31, 2021$ / bblbbl
Three-way Collars: April 1, to June 30, 2021
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (in barrels of oil per day) | bbl	14,000
Premium (Weighted Average) (in dollars per bbl)	0.21
Three-way Collars: April 1, to June 30, 2021 | Sold | Put
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Sold Price (Weighted Average) (in dollars per bbl)	36.43
Three-way Collars: April 1, to June 30, 2021 | Sold | Call
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Sold Price (Weighted Average) (in dollars per bbl)	51.45
Three-way Collars: April 1, to June 30, 2021 | Purchased | Put
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Purchased Put (in dollars per barrel)	45.14
Collars: April 1, to June 30, 2021
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (in barrels of oil per day) | bbl	1,000
Collars: April 1, to June 30, 2021 | Sold | Call
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Sold Price (Weighted Average) (in dollars per bbl)	50.40
Collars: April 1, to June 30, 2021 | Purchased | Put
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Purchased Put (in dollars per barrel)	45
Three-way Collars: July 1, to December 31, 2021
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (in barrels of oil per day) | bbl		4,000
Three-way Collars: July 1, to December 31, 2021 | Sold | Put
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Sold Price (Weighted Average) (in dollars per bbl)		45
Three-way Collars: July 1, to December 31, 2021 | Sold | Call
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Sold Price (Weighted Average) (in dollars per bbl)		68
Three-way Collars: July 1, to December 31, 2021 | Purchased | Put
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Purchased Put (in dollars per barrel)		55
Swaptions: July 1, to December 31, 2021
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (in barrels of oil per day) | bbl		3,000
Swaptions: July 1, to December 31, 2021 | Sold | Call
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Sold Price (Weighted Average) (in dollars per bbl)		56.75
Three-way Collars: July 1, to December 31, 2021
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (in barrels of oil per day) | bbl		3,000
Three-way Collars: July 1, to December 31, 2021 | Sold | Put
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Sold Price (Weighted Average) (in dollars per bbl)		50
Three-way Collars: July 1, to December 31, 2021 | Sold | Call
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Sold Price (Weighted Average) (in dollars per bbl)		70.21
Three-way Collars: July 1, to December 31, 2021 | Purchased | Put
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Purchased Put (in dollars per barrel)		60

Financial Instruments and Fai_7

Financial Instruments and Fair Value Measurement - Schedule of Outstanding Foreign Currency Derivative Positions (Details) - Forecast - Collars: April 1, to December 31, 2021 $ in Thousands, $ in Thousands	Dec. 31, 2021COP ($)$ / collar	Dec. 31, 2021USD ($)$ / collar
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount Hedged	$ 9,000,000	$ 2,408
Sold | Put
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Floor Price (COP, Weighted Average)	3,500	3,500
Purchased | Call
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Cap Price (COP, Weighted Average)	3,630	3,630

Supplemental Cash Flow Inform_3

Supplemental Cash Flow Information - Reconciliation of Cash, Cash Equivalents and Restricted Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Supplemental Cash Flow Elements [Abstract]
Cash and cash equivalents	$ 21,649	$ 14,114	$ 39,767	$ 8,817
Restricted cash and cash equivalents - long-term	3,219	3,409	1,995	2,258
Cash, cash equivalents and restricted cash and cash equivalents	$ 24,868	$ 17,523	$ 41,762	$ 11,075

Supplemental Cash Flow Inform_4

Supplemental Cash Flow Information - Schedule of Net Changes in Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Supplemental Cash Flow Elements [Abstract]
Accounts receivable and other long-term assets	$ 3,803	$ 29,577
Derivatives	3,841	(3,873)
Inventory	(1,146)	(1,473)
Prepaids	157	15
Accounts payable and accrued and other long-term liabilities	752	(32,283)
Taxes receivable and payable	5,721	(8,665)
Net changes in assets and liabilities from operating activities	13,128	(16,702)
Increase (decrease) in accounts payable and accrued liabilities	(800)	(19,000)
Increase in accounts receivable	$ (100)	$ (1,200)

Supplemental Cash Flow Inform_5

Supplemental Cash Flow Information - Schedule of Additional Supplemental Cash Flow Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Supplemental Cash Flow Elements [Abstract]
Cash paid for income taxes	$ 5,034	$ 5,208
Cash paid for interest	11,479	10,752
Non-cash investing activities:
Net liabilities related to property, plant and equipment, end of period	$ 28,003	$ 59,503