Teekay Tankers (TNK) 6-K 24 Nov 20 2020 Q3 Current report (foreign) Financial data

Document and Entity Information

Document and Entity Information	9 Months Ended
	Sep. 30, 2020
Document And Entity Information [Abstract]
Document Type	6-K
Amendment Flag	false
Document Period End Date	Sep. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Entity Registrant Name	TEEKAY TANKERS LTD.
Entity Central Index Key	0001419945
Current Fiscal Year End Date	--12-31

Unaudited Consolidated Statemen

Unaudited Consolidated Statements of Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Total revenues	$ 170,240	$ 187,444	$ 758,632	$ 632,612
Voyage expenses	(57,777)	(92,866)	(238,576)	(293,263)
Vessel operating expenses (note 13b)	(46,336)	(48,539)	(143,203)	(156,726)
Time-charter hire expenses	9,070	10,637	28,245	30,877
Depreciation and amortization	(29,992)	(31,536)	(89,170)	(92,059)
General and administrative expenses (note 13b)	(9,887)	(8,739)	(28,957)	(27,412)
Gain (loss) on sale of assets and write-down of assets (note15)	(44,973)	0	(45,164)	0
Restructuring Charges	(1,398)	0	(1,398)	0
(Loss) income from operations	(29,193)	(4,873)	183,919	32,275
Interest expense	(12,553)	(16,134)	(41,180)	(49,683)
Interest income	337	138	1,160	724
Realized and unrealized (loss) gain on derivative instruments (note 8)	(414)	1,453	(1,830)	(1,172)
Equity income	46	68	5,174	652
Other (expense) income (note 9)	(470)	933	1,613	1,182
Net (loss) income before income tax	(42,247)	(18,415)	148,856	(16,022)
Income tax (expense) recovery (note 10)	(2,187)	(1,435)	11,747	(5,688)
Net income (loss)	$ (44,434)	$ (19,850)	$ 160,603	$ (21,710)
Per common share amounts (note 14)
- Basic (loss) earnings per share	$ (1.32)	$ (0.59)	$ 4.76	$ (0.65)
- Diluted (loss) earnings per share	$ (1.32)	$ (0.59)	$ 4.73	$ (0.65)
Weighted-average number of Class A and Class B common stock outstanding (note 14)
- Basic	33,738,143	33,623,608	33,712,124	33,610,936
- Diluted	33,738,143	33,623,608	33,942,191	33,610,936
Voyage charter revenues
Total revenues	$ 125,819	$ 178,174	$ 651,223	$ 591,746
Time-charter [Member]
Total revenues	42,180	1,909	92,733	6,815
Other revenues
Total revenues	$ 2,241	$ 7,361	$ 14,676	$ 34,051

Unaudited Consolidated Balance

Unaudited Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current
Cash and cash equivalents	$ 120,872	$ 88,824
Restricted cash – current (note 16)	4,686	3,071
Accounts receivable	46,247	95,648
Assets held for sale (note 15)	0	65,458
Due from affiliates (note 13c)	3,323	697
Current portion of derivative assets (note 8)	0	577
Bunker and lube oil inventory	33,444	49,790
Prepaid expenses	13,561	10,288
Accrued revenue	29,410	106,872
Total current assets	251,543	421,225
Restricted cash – long-term (note 16)	3,437	3,437
At cost, less accumulated depreciation of $496.4 million (2019 - $537.1 million) (note 6)	1,131,742	1,223,085
Vessels related to finance leases, at cost, less accumulated depreciation of $126.9 million (2019 - $143.7 million) (note 7)	484,776	527,081
Operating lease right-of-use assets (note 7)	6,148	19,560
Total vessels and equipment	1,622,666	1,769,726
Investment in and advances to equity-accounted joint venture	28,635	28,112
Derivative Assets (note 8)	0	82
Other non-current assets	1,175	1,923
Intangible assets at cost, less accumulated amortization of $3.6 million (2019 - $3.2 million)	2,122	2,545
Goodwill	2,426	2,426
Consolidated total assets	1,912,004	2,229,476
Current
Accounts payable	41,761	70,978
Accrued liabilities (notes 13c and 17)	41,511	59,735
Short-term debt (note 5)	20,000	50,000
Due to affiliates (note 13c)	2,932	2,139
Liabilities associated with assets held for sale (note 15)	0	2,980
Current portion of derivative liabilities (note 8)	755	86
Current portion of long-term debt (note 6)	10,962	43,573
Current obligations related to finance leases (note 7)	26,794	25,357
Current portion of operating lease liabilities (note 7)	7,602	16,290
Other current liabilities	3,696	8,567
Total current liabilities	156,013	279,705
Long-term debt (note 6)	204,103	516,106
Long-term obligations related to finance leases (note 7)	369,278	389,431
Long-term operating lease liabilities (note 7)	421	3,270
Derivative liabilities (note 8)	717	0
Other long-term liabilities (note 10)	29,683	51,044
Total liabilities	760,215	1,239,556
Equity
Common stock and additional paid-in capital (585.0 million shares authorized, 29.1 million Class A and 4.6 million Class B shares issued and outstanding as of September 30, 2020 and 585.0 million shares authorized, 29.0 million Class A and 4.6 million Class B shares issued and outstanding as at December 31, 2019) (note 12)	1,298,821	1,297,555
Accumulated deficit	(147,032)	(307,635)
Total equity	1,151,789	989,920
Total liabilities and equity	$ 1,912,004	$ 2,229,476

Unaudited Consolidated Balanc_2

Unaudited Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Excluding Capital Leased Assets	$ 496.4	$ 537.1
Sale Leaseback Transaction, Accumulated Depreciation	126.9	143.7
Accumulated amortization on intangible assets	$ 3.6	$ 3.2
Common stock, shares authorized (in shares)	585,000,000	585,000,000
Class A
Common stock, shares authorized (in shares)	485,000,000	485,000,000
Common stock, shares issued (in shares)	29,100,000	29,000,000
Common Stock, Shares, Outstanding	29,100,000	29,000,000
Class B
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	4,600,000	4,600,000
Common Stock, Shares, Outstanding	4,600,000	4,600,000

Unaudited Consolidated Statem_2

Unaudited Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019
OPERATING ACTIVITIES
Net income (loss)	$ (44,434)	$ 160,603	$ (21,710)
Non-cash items:
Depreciation and amortization	29,992	89,170	92,059
Loss on Sale of Assets and Write-Down of Assets	44,973	45,164	0
Unrealized loss on derivative instruments (note 8)		1,948	3,960
Equity income	(46)	(5,174)	(652)
Income tax (recovery) expense (note 10)	(2,187)	11,747	(5,688)
Other		3,827	3,690
Change in operating assets and liabilities		72,629	18,685
Expenditures for dry docking		(9,405)	(37,430)
Net operating cash flow		347,811	62,783
FINANCING ACTIVITIES
Proceeds from short-term debt (note 5)		235,000	125,000
Proceeds from long-term debt, net of issuance costs (note 6)		544,872	56,788
Scheduled repayments of long-term debt (note 6)		(10,366)	(76,216)
Prepayments of long-term debt (note 6)		882,495	109,688
Prepayments of short-term debt (note 5)		(265,000)	(75,000)
Proceeds from financing related to sales and leaseback of vessels (note 8)		0	63,720
Scheduled repayments of obligations related to finance leases (note 7)		(18,716)	(18,075)
Proceeds from (Payments for) Other Financing Activities		(562)	(126)
Net financing cash flow		(397,267)	(33,597)
INVESTING ACTIVITIES
Proceeds from sale of assets (net of cash sold of $2.1 million) (note 15)		85,892	0
Expenditures for vessels and equipment		(8,881)	(7,210)
Proceeds from (Repayments of) Related Party Debt		4,650	0
Net investing cash flow		81,661	(7,210)
Increase in cash, cash equivalents and restricted cash		32,205	21,976
Cash, cash equivalents and restricted cash, beginning of the period		96,790	60,507
Cash, cash equivalents and restricted cash, end of the period	128,995	128,995	82,483
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents	$ 2,100	2,100
Freight Tax [Member]
Non-cash items:
Income tax (recovery) expense (note 10)		$ (10,951)	$ 4,181

Unaudited Consolidated Statem_3

Unaudited Consolidated Statement of Changes in Equity - USD ($) shares in Thousands, $ in Thousands	Total	Class A	Class B	Common Stock and Additional Paid-in Capital	Common Stock and Additional Paid-in CapitalClass A	Common Stock and Additional Paid-in CapitalClass B	Accumulated Deficit
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	$ 12,447						$ 12,447
Stock Issued During Period, Shares, Employee Benefit Plan				54
Equity-based compensation (note 12)	668				$ 668
Balance at start of period, shares at Dec. 31, 2018				33,570
Balance at end of period at Mar. 31, 2019	960,048				1,208,065	$ 88,532	(336,549)
Balance at end of period (shares) at Mar. 31, 2019				33,624
Balance at start of period at Dec. 31, 2018	946,933				1,207,397	88,532	(348,996)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(21,710)
Balance at start of period, shares at Dec. 31, 2018				33,570
Balance at end of period at Sep. 30, 2019	926,287				1,208,461	88,532	(370,706)
Balance at end of period (shares) at Sep. 30, 2019				33,624
Balance at start of period at Dec. 31, 2018	946,933				1,207,397	88,532	(348,996)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(14,307)						(14,307)
Stock Issued During Period, Shares, Employee Benefit Plan				0
Equity-based compensation (note 12)	154				154
Balance at start of period, shares at Mar. 31, 2019				33,624
Balance at end of period at Jun. 30, 2019	945,895				1,208,219	88,532	(350,856)
Balance at end of period (shares) at Jun. 30, 2019				33,624
Balance at start of period at Mar. 31, 2019	960,048				1,208,065	88,532	(336,549)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(19,850)						(19,850)
Equity-based compensation (note 12)	242				242
Balance at end of period at Sep. 30, 2019	926,287				1,208,461	88,532	(370,706)
Balance at end of period (shares) at Sep. 30, 2019				33,624
Balance at start of period at Jun. 30, 2019	945,895				1,208,219	88,532	(350,856)
Balance at beginning of period (shares) at Dec. 31, 2019				33,655
Balance at end of period (shares) at Mar. 31, 2020				33,712
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	106,839						106,839
Stock Issued During Period, Shares, Employee Benefit Plan				57
Equity-based compensation (note 12)	468				468
Balance at start of period, shares at Dec. 31, 2019		29,000	4,600
Balance at end of period at Mar. 31, 2020	1,097,227				1,209,491	88,532	(200,796)
Balance at start of period at Dec. 31, 2019	989,920				1,209,023	88,532	(307,635)
Balance at beginning of period (shares) at Dec. 31, 2019				33,655
Balance at end of period (shares) at Sep. 30, 2020				33,738
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	160,603
Balance at start of period, shares at Dec. 31, 2019		29,000	4,600
Balance at end of period at Sep. 30, 2020	1,151,789				1,210,289	88,532	(147,032)
Balance at end of period (shares) at Sep. 30, 2020		29,100	4,600
Balance at start of period at Dec. 31, 2019	989,920				1,209,023	88,532	(307,635)
Balance at beginning of period (shares) at Mar. 31, 2020				33,712
Balance at end of period (shares) at Jun. 30, 2020				33,738
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	98,198						98,198
Stock Issued During Period, Shares, Employee Benefit Plan				26
Equity-based compensation (note 12)	374				374
Balance at end of period at Jun. 30, 2020	1,195,799				1,209,865	88,532	(102,598)
Balance at start of period at Mar. 31, 2020	1,097,227				1,209,491	88,532	(200,796)
Balance at end of period (shares) at Sep. 30, 2020				33,738
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(44,434)						(44,434)
Equity-based compensation (note 12)	424				424
Balance at end of period at Sep. 30, 2020	1,151,789				1,210,289	88,532	(147,032)
Balance at end of period (shares) at Sep. 30, 2020		29,100	4,600
Balance at start of period at Jun. 30, 2020	$ 1,195,799				$ 1,209,865	$ 88,532	$ (102,598)

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	9 Months Ended
	Sep. 30, 2020
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	Supplemental Cash Flow Information Total cash, cash equivalents and restricted cash, including cash, cash equivalents and restricted cash held for sale are as follows: As at As at As at As at September 30, 2020 December 31, 2019 September 30, 2019 December 31, 2018 $ $ $ $ Cash and cash equivalents 120,872 88,824 76,705 54,917 Restricted cash – current 4,686 3,071 2,341 2,153 Restricted cash – long-term 3,437 3,437 3,437 3,437 Cash and cash equivalents held for sale — 1,121 — — Restricted cash held for sale - current — 337 — — 128,995 96,790 82,483 60,507 The Company maintains restricted cash deposits relating to certain FFAs (note 8) and leasing arrangements (note 7). Non-cash items related to operating lease right-of-use assets and operating lease liabilities are as follows: For the nine months ended September 30, 2020 September 30, 2019 $ $ Leased assets obtained in exchange for new operating lease liabilities 835 22,432

Liquidity

Liquidity	9 Months Ended
	Sep. 30, 2020
Liquidity [Abstract]
Substantial Doubt about Going Concern [Text Block]	18. Liquidity Based on the Company's liquidity as at the date these unaudited consolidated financial statements were issued, and from the expected cash flows from Company's operations over the following year, the Company estimates that it will have sufficient liquidity to continue as a going concern for at least a one-year period following the issuance of these unaudited consolidated financial statements.

Supplemental Cash Flow Inform_2

Supplemental Cash Flow Information Tables	9 Months Ended
	Sep. 30, 2020
Supplemental Cash Flow Elements [Abstract]
Schedule of Cash Flow, Supplemental Disclosures	Total cash, cash equivalents and restricted cash, including cash, cash equivalents and restricted cash held for sale are as follows: As at As at As at As at September 30, 2020 December 31, 2019 September 30, 2019 December 31, 2018 $ $ $ $ Cash and cash equivalents 120,872 88,824 76,705 54,917 Restricted cash – current 4,686 3,071 2,341 2,153 Restricted cash – long-term 3,437 3,437 3,437 3,437 Cash and cash equivalents held for sale — 1,121 — — Restricted cash held for sale - current — 337 — — 128,995 96,790 82,483 60,507 The Company maintains restricted cash deposits relating to certain FFAs (note 8) and leasing arrangements (note 7). Non-cash items related to operating lease right-of-use assets and operating lease liabilities are as follows: For the nine months ended September 30, 2020 September 30, 2019 $ $ Leased assets obtained in exchange for new operating lease liabilities 835 22,432

Supplemental Cash Flow Inform_3

Supplemental Cash Flow Information Details - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Supplemental Cash Flow [Line Items]
Cash and cash equivalents	$ 120,872	$ 76,705	$ 88,824	$ 54,917
Restricted cash – current (note 16)	4,686	2,341	3,071	2,153
Restricted cash – long-term (note 17)	3,437	3,437	3,437	3,437
Cash, cash equivalents and restricted cash	128,995	82,483	96,790	60,507
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	835	22,432
Cash and Cash Equivalents [Member]
Schedule Of Supplemental Cash Flow [Line Items]
Cash and cash equivalents	0	0	1,121	0
Restricted Cash [Member]
Schedule Of Supplemental Cash Flow [Line Items]
Restricted Cash and Cash Equivalents	$ 0	$ 0	$ 337	$ 0

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The unaudited interim consolidated financial statements (or unaudited consolidated financial statements ) have been prepared in accordance with United States generally accepted accounting principles (or GAAP ). These unaudited consolidated financial statements include the accounts of Teekay Tankers Ltd., its wholly-owned subsidiaries, equity-accounted joint venture and any variable interest entities (or VIEs ) of which it is the primary beneficiary (collectively, the Company ). The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the unaudited consolidated financial statements and accompanying notes. Actual results could differ from those estimates. Certain information and footnote disclosures required by GAAP for complete annual financial statements have been omitted and, therefore, these unaudited consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements for the year ended December 31, 2019, filed on Form 20-F with the U.S. Securities and Exchange Commission (or the SEC ) on April 15, 2020. In the opinion of management, these unaudited consolidated financial statements reflect all adjustments, consisting solely of a normal recurring nature, necessary to present fairly, in all material respects, the Company’s unaudited consolidated financial position, results of operations, and cash flows for the interim periods presented. The results of operations for the interim periods presented are not necessarily indicative of those for a full fiscal year. Intercompany balances and transactions have been eliminated upon consolidation. In March 2020, the World Health Organization declared the outbreak of a novel coronavirus (or COVID-19 ) as a pandemic. Given the dynamic nature of these circumstances, the full extent to which the COVID-19 pandemic may have direct or indirect impact on the Company's business and the related financial reporting implications cannot be reasonably estimated at this time, although the pandemic could materially affect the Company's business, results of operations and financial condition in the future. COVID-19 has resulted and may continue to result in a significant decline in global demand for oil. As the Company's business includes the transportation of crude oil and refined petroleum products on behalf of customers, any significant decrease in demand for the cargo the Company transports could adversely affect demand for the Company's vessels and services. Spot tanker rates have come under pressure since mid-May 2020 as a result of record OPEC+ oil production cuts and lower production from other oil producing countries, which reduced crude exports, and the unwinding of floating storage. COVID-19 has also been a contributing factor to the decline in short-term charter rates and the increase in certain crewing-related costs, which has had an impact on our cash flows, and was a contributing factor to the write-down of certain tankers during the nine months ended September 30, 2020 as described in Note 15 - Write-down and Loss on Sale of Assets and the reduction in certain tax accruals as described in Note 10 - Income Tax (Expense) Recovery. Voyage Charter Revenues and Expenses Voyage expenses incurred that are recoverable from the Company's customers in connection with its voyage charter contracts are reflected in voyage charter revenues and voyage expenses. The Company recast prior periods to reflect this presentation. This had the impact of increasing both voyage charter revenues and voyage expenses by $5.1 million and $15.5 million for the three and nine months ended September 30, 2019, respectively. Reverse Stock Split The per share amounts for all periods presented have been adjusted to reflect a one-for-eight reverse stock split completed in November 2019.

Revenue

Revenue	9 Months Ended
	Sep. 30, 2020
Revenue from Contract with Customer [Abstract]
Revenue	Revenue The Company’s primary source of revenue is from chartering its vessels (Aframax tankers, Suezmax tankers and Long Range 2 (or LR2 ) tankers) to its customers. The Company utilizes two primary forms of contracts, consisting of voyage charters and time-charters. The extent to which the Company employs its vessels on voyage charters versus time charters is dependent upon the Company’s chartering strategy and the availability of time charters. Spot market rates for voyage charters are volatile from period to period, whereas time charters provide a stable source of monthly revenue. The Company also provides ship-to-ship support services, which include managing the process of transferring cargo between seagoing ships positioned alongside each other, either stationary or underway, as well as commercial management services to third-party owners of vessels. Prior to April 30, 2020, the Company managed liquefied natural gas (or LNG ) terminals and procured LNG-related goods for terminal owners and other customers. For descriptions of these types of contracts, see Item 18 - Financial Statements: Note 3 in the Company’s audited consolidated financial statements filed with its Annual Report on Form 20-F for the year ended December 31, 2019. On April 30, 2020, the Company completed the sale of the non-US portion of its ship-to-ship support services business, as well as its LNG terminal management business (see note 15). The following table contains a breakdown of the Company's revenue by contract type for the three and nine months ended September 30, 2020 and September 30, 2019. All revenue is part of the Company's tanker segment, except for revenue for the non-US portion of the ship-to-ship support services and LNG terminal management, consultancy, procurement, and other related services, which are part of the Company's previously existing ship-to-ship transfer segment. The Company’s lease income consists of the revenue from its voyage charters and time-charters. Three Months Ended September 30, Nine Months Ended September 30, 2020 2019 2020 2019 $ $ $ $ Voyage charter revenues Suezmax 51,134 87,963 302,839 276,972 Aframax 38,847 52,845 170,680 167,981 LR2 17,007 24,759 93,666 86,711 Full service lightering 18,831 12,607 84,038 60,082 Total 125,819 178,174 651,223 591,746 Time-charter revenues Suezmax 35,133 1,909 81,700 4,978 Aframax 4,725 — 6,883 1,837 LR2 2,322 — 4,150 — Total 42,180 1,909 92,733 6,815 Other revenues Ship-to-ship support services 777 4,649 8,619 17,810 Commercial management 1,464 1,893 5,665 6,219 LNG terminal management, consultancy, procurement and other — 819 392 10,022 Total 2,241 7,361 14,676 34,051 Total revenues 170,240 187,444 758,632 632,612 Charters-out As at September 30, 2020, 11 (December 31, 2019 - five) of the Company’s vessels operated under fixed-rate time charter contracts, three of which are scheduled to expire in 2020, six of which are scheduled to expire in 2021 and two of which are scheduled to expire in 2022. As at September 30, 2020, the minimum scheduled future revenues to be received by the Company under these time charters were approximately $31.6 million (remainder of 2020), $41.7 million (2021) and $5.2 million (2022) (December 31, 2019 - $40.0 million (2020)). The hire payments should not be construed to reflect a forecast of total charter hire revenue for any of the periods. Future hire payments do not include hire payments generated from new contracts entered into after September 30, 2020, from unexercised option periods of contracts that existed on September 30, 2020 or from variable consideration, if any, under contracts. In addition, future hire payments presented above have been reduced by estimated off-hire time for required periodic maintenance and do not reflect the impact of revenue sharing arrangements whereby time-charter revenues are shared with other revenue sharing arrangement participants. Actual amounts may vary given future events such as unplanned vessel maintenance. Contract Liabilities As at September 30, 2020, the Company had $3.1 million (December 31, 2019 - $7.5 million) of advanced payments recognized as contract liabilities that are expected to be recognized as time-charter revenues in subsequent periods and which currently are included in other current liabilities on the Company's unaudited consolidated balance sheets.

Segment Reporting

Segment Reporting	9 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Segment Reporting	Segment Reporting On April 30, 2020, the Company completed the sale of the non-US portion of its ship-to-ship support services business, as well as its LNG terminal management business. Following the sale, the Company's remaining ship-to-ship support operations were integrated into the Company's tanker business. As a result, effective April 30, 2020, the Company has one reportable segment. The Company’s segment information for all periods prior to the sale and reorganization has been retroactively adjusted whereby the remaining ship-to-ship support operations have been reallocated from the ship-to-ship transfer segment to the tanker segment. Consequently, the Company’s tanker segment now consists of the operation of all of its tankers, including the operations from those tankers employed on full service lightering contracts, and the US based ship-to-ship support service operations that the Company retained, including its lightering support services provided as part of full service lightering operations. The Company’s ship-to-ship transfer segment consisted of the Company’s non-US lightering support services, LNG terminal management, consultancy, procurement, and other related services which were sold as of April 30, 2020. Segment results are evaluated based on (loss) income from operations. The accounting policies applied to the reportable segments are the same as those used in the preparation of the Company’s unaudited consolidated financial statements. The following tables include results for the Company’s revenues and (loss) income from operations by segment for the nine months ended September 30, 2020 and three and nine months ended September 30, 2019. No results are included for the three months ended September 30, 2020 as the Company only had one reportable segment during that period. Three Months Ended September 30, 2019 Tanker Segment Ship-to-Ship Transfer Segment Total $ $ $ Revenues (1) 182,429 5,015 187,444 Voyage expenses (92,866) — (92,866) Vessel operating expenses (44,322) (4,217) (48,539) Time-charter hire expenses (10,637) — (10,637) Depreciation and amortization (30,806) (730) (31,536) General and administrative expenses (2) (8,380) (359) (8,739) Loss from operations (4,582) (291) (4,873) Equity income 68 — 68 Nine Months Ended September 30, 2020 Tanker Segment Ship-to-Ship Transfer Segment Total $ $ $ Revenues (1) 751,640 6,992 758,632 Voyage expenses (238,576) — (238,576) Vessel operating expenses (137,263) (5,940) (143,203) Time-charter hire expenses (28,245) — (28,245) Depreciation and amortization (88,677) (493) (89,170) General and administrative expenses (2) (28,330) (627) (28,957) (Loss) gain on sale of assets and write-down of assets (48,245) 3,081 (45,164) Restructuring charge (1,398) — (1,398) Income from operations 180,906 3,013 183,919 Equity income 5,174 — 5,174 Nine Months Ended September 30, 2019 Tanker Segment Ship-to-Ship Transfer Segment Total $ $ $ Revenues (1) 608,815 23,797 632,612 Voyage expenses (293,263) — (293,263) Vessel operating expenses (137,461) (19,265) (156,726) Time-charter hire expenses (30,877) — (30,877) Depreciation and amortization (89,921) (2,138) (92,059) General and administrative expenses (2) (26,295) (1,117) (27,412) Income from operations 30,998 1,277 32,275 Equity income 652 — 652 A reconciliation of total segment assets to total assets presented in the accompanying unaudited consolidated balance sheet as at December 31, 2019, when the Company had more than one reportable segment, is as follows: As at December 31, 2019 $ Tanker 2,114,451 Ship-to-Ship Transfer 26,201 Cash and cash equivalents 88,824 Consolidated total assets 2,229,476

Short-Term Debt

Short-Term Debt	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Short-term Debt	Short-Term Debt In November 2018, Teekay Tankers Chartering Pte. Ltd. (or TTCL ) a wholly-owned subsidiary of the Company, entered into a working capital revolving loan facility (or the Working Capital Loan ), which initially provided available aggregate borrowings of up to $40.0 million for TTCL, and had an initial maturity date in May 2019, subject to extension as described below. The maximum available aggregate borrowings were subsequently increased to $80.0 million, effective December 2019. The amount available for drawdown is limited to a percentage of certain receivables and accrued revenue, which is assessed weekly. The next maturity date of the Working Capital Loan is in November 2020. The Working Capital Loan maturity date is continually extended for further periods of six months thereafter unless and until the lender gives notice in writing that no further extensions shall occur. Proceeds of the Working Capital Loan are used to provide working capital in relation to certain vessels subject to the revenue sharing agreements (or RSAs). Interest payments are based on LIBOR plus a margin of 3.5%. The Working Capital Loan is collateralized by the assets of TTCL. The Working Capital Loan requires the Company to maintain its paid-in capital contribution under the RSAs and the retained distributions of the RSA counterparties in an amount equal to the greater of (a) an amount equal to the minimum average capital contributed by the RSA counterparties per vessel in respect of the RSA (including cash, bunkers or other working capital contributions and amounts accrued to the RSA counterparties but unpaid) and (b) a minimum capital contribution ranging from $20.0 million to $30.0 million based on the amount borrowed. As at September 30, 2020, $20.0 million (December 31, 2019 - $50.0 million) was owing under this facility, and the interest rate on the facility was 3.6% (December 31, 2019 - 5.0%). As of the date these unaudited consolidated financial statements were issued, the Company was in compliance with all covenants in respect of this facility.

Long-Term Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Debt Disclosure	Long-Term Debt As at As at September 30, 2020 December 31, 2019 $ $ Revolving Credit Facilities due through 2024 155,000 341,132 Term Loans due through 2023 67,375 221,729 Total principal 222,375 562,861 Less: unamortized discount and debt issuance costs (7,310) (3,182) Total debt 215,065 559,679 Less: current portion (10,962) (43,573) Long-term portion 204,103 516,106 As at September 30, 2020, the Company had one revolving credit facility (or the 2020 Revolver ) (December 31, 2019 - two revolving facilities), which, as at such date, provided for aggregate borrowings of up to $485.6 million, of which $330.6 million was undrawn (December 31, 2019 - $371.5 million, of which $30.4 million was undrawn). Interest payments are based on LIBOR plus a margin, which was 2.40% as at September 30, 2020 (December 31, 2019 - ranged from 2.00% to 2.75%). The total amount available under the 2020 Revolver decreases by $47.2 million (remainder of 2020), $91.4 million (2021), $80.4 million (2022), $65.3 million (2023) and $201.3 million (2024). As at September 30, 2020, the Company also had one term loan (or the 2020 Term Loan ) outstanding (December 31, 2019 - three), which totaled $67.4 million (December 31, 2019 - $221.7 million). Interest payments are based on LIBOR plus a margin, which was 2.25% as at September 30, 2020 (December 31, 2019 - based on a combination of a fixed rate of 5.40% and variable rates based on LIBOR plus margins, which ranged from 0.30% to 2.00%). The term loan reduces in quarterly payments and has a balloon repayment due at maturity in 2023. The 2020 Revolver and 2020 Term Loan are further described below. In January 2020, the Company entered into the 2020 Revolver, which is scheduled to mature in December 2024, and which had an outstanding balance of $155.0 million as at September 30, 2020. The 2020 Revolver was used to repay a portion of the $455.3 million previously outstanding under two previous revolving credit facilities of the Company, which were scheduled to mature in 2021 and 2022, and under two term loan facilities, which were scheduled to mature in 2020 and 2021. The 2020 Revolver is collateralized by 31 of the Company's vessels, together with other related security. The 2020 Revolver requires that the Company maintain a minimum hull coverage ratio of 125% of the total outstanding drawn balance for the facility period. Such requirement is assessed on a semi-annual basis with reference to vessel valuations compiled by two or more agreed upon third parties. Should the ratio drop below the required amount, the lender may request that the Company either prepay a portion of the loan in the amount of the shortfall or provide additional collateral in the amount of the shortfall, at the Company's option. As at September 30, 2020, the hull coverage ratio was 483%. A decline in the tanker market could negatively affect the ratio. In addition, the Company is required to maintain a minimum liquidity (cash, cash equivalents and undrawn committed revolving credit lines with at least six months to maturity) of $35.0 million and at least 5% of the Company's total consolidated debt and obligations related to finance leases. In August 2020, the Company entered into the 2020 Term Loan, which is scheduled to mature in August 2023, and which had an outstanding balance of $67.4 million as at September 30, 2020. The 2020 Term Loan was used to repay a portion of the $85.1 million previously outstanding under one previous term loan facility, which was scheduled to mature in 2021. The 2020 Term Loan is collateralized by four of the Company's vessels, together with other related security. The 2020 Term Loan requires that the Company maintain a minimum hull coverage ratio of 125% of the total outstanding principal balance for the loan period. Such requirement is assessed on a semi-annual basis with reference to vessel valuations compiled by two or more agreed upon third parties. Should the ratio drop below the required amount, the lender may request that the Company either prepay a portion of the loan in the amount of the shortfall or provide additional collateral in the amount of the shortfall, at the Company's option. As at September 30, 2020, the hull coverage ratio was 182%. A decline in the tanker market could negatively affect the ratio. In addition, the Company is required to maintain a minimum liquidity (cash, cash equivalents and undrawn committed revolving credit lines with at least six months to maturity) of $35.0 million and at least 5% of the Company's total consolidated debt and obligations related to finance leases. As of the date these unaudited consolidated financial statements were issued, the Company was in compliance with all covenants in respect of the 2020 Revolver and the 2020 Term Loan. The weighted-average interest rate on the Company’s long-term debt as at September 30, 2020 was 2.6% (December 31, 2019 - 3.7%). This rate does not reflect the effect of the Company’s interest rate swap agreement (note 8). The aggregate annual long-term debt principal repayments required to be made by the Company under the 2020 Revolver and the 2020 Term Loan subsequent to September 30, 2020, are $2.8 million (remainder of 2020), $11.2 million (2021), $11.2 million (2022), $42.2 million (2023) and $155.0 million (2024).

Leases

Leases	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Lessee, Operating Leases [Text Block]	Operating Leases The Company charters-in vessels from other vessel owners on time-charter contracts, whereby the vessel owner provides use and technical operation of the vessel for the Company. A time charter-in contract is typically for a fixed period of time, although in certain cases, the Company may have the option to extend the charter. The Company typically pays the owner a daily hire rate that is fixed over the duration of the charter. The Company is generally not required to pay the daily hire rate during periods the vessel is not able to operate. As at September 30, 2020, minimum commitments to be incurred by the Company under time charter-in contracts were approximately $8.9 million (remainder of 2020), $10.5 million (2021) and $1.5 million (2022).
Lessee, Finance Leases	Obligations Related to Finance Leases As at As at September 30, 2020 December 31, 2019 $ $ Total obligations related to finance leases 396,072 414,788 Less: current portion (26,794) (25,357) Long-term obligations related to finance leases 369,278 389,431 From 2017 to 2019, the Company completed sale-leaseback financing transactions with financial institutions relating to 16 of the Company's vessels. Under these arrangements, the Company transferred the vessels to subsidiaries of the financial institutions (collectively, the Lessors ) and leased the vessels back from the Lessors on bareboat charters ranging from 9- to 12-year terms. The Company is obligated to purchase eight of the vessels upon maturity of their respective bareboat charters. The Company also has the option to purchase each of the 16 vessels at various times starting between July 2020 and November 2021 until the end of their respective lease terms. In October 2020, the Company completed the purchases of two of these vessels for a total cost of $29.6 million and in November 2020, the Company declared purchase options to acquire two more of these vessels for a total cost of $56.7 million with an expected completion date of May 2021 (see note 19). The bareboat charters related to these vessels require that the Company maintain a minimum liquidity (cash, cash equivalents and undrawn committed revolving credit lines with at least six months to maturity) of $35.0 million and at least 5.0% of the Company's consolidated debt and obligations related to finance leases. Four bareboat charters, entered into in July 2017, require the Company to maintain, for each vessel, a minimum hull coverage ratio of 90% of the total outstanding principal balance during the first three years of the lease period and 100% of the total outstanding principal balance thereafter. As at September 30, 2020, these ratios ranged from 119% to 141% (December 31, 2019 - ranged from 110% to 132%). Six bareboat charters, entered into in September 2018, require the Company to maintain, for each vessel, a minimum hull coverage ratio of 75% of the total outstanding principal balance during the first year of the lease period, 78% for the second year, 80% for the following two years and 90% of the total outstanding principal balance thereafter. As at September 30, 2020, these ratios ranged from 87% to 104% (December 31, 2019 - ranged from 106% to 123%). Four bareboat charters, entered into in November 2018, require the Company to maintain, for each vessel, a minimum hull coverage ratio of 100% of the total outstanding principal balance. As at September 30, 2020, these ratios ranged from 113% to 156% (December 31, 2019 - ranged from 140% to 173%). Two bareboat charters, entered into in May 2019, require the Company to maintain, for each vessel, a minimum hull coverage ratio of 75% of the total outstanding principal balance during the first year of the lease period, 78% for the second year, 80% for the following two years and 90% of the total outstanding principal balance thereafter. As at September 30, 2020, these ratios were 91% (December 31, 2019 - 109%). Such requirements are assessed annually or quarterly with reference to vessel valuations compiled by one or more agreed upon third parties. As of the date these unaudited consolidated financial statements were issued, the Company was in compliance with all covenants in respect of its obligations related to finance leases. The weighted-average interest rate on the Company’s obligations related to finance leases as at September 30, 2020 was 7.6% (December 31, 2019 - 7.6%). As at September 30, 2020, the Company's total remaining commitments related to the financial liabilities of these vessels were approximately $559.7 million (December 31, 2019 - $601.7 million), including imputed interest of $163.6 million (December 31, 2019 - $186.9 million), repayable from 2020 through 2030, as indicated below: Commitments Year September 30, 2020 Remainder of 2020 14,235 2021 56,222 2022 56,213 2023 56,204 2024 56,348 Thereafter 320,481

Derivative Instruments

Derivative Instruments	9 Months Ended
	Sep. 30, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments Interest rate swap agreement The Company uses derivative instruments in accordance with its overall risk management policies. The Company enters into interest rate swap agreements which exchange a receipt of floating interest for a payment of fixed interest to reduce the Company’s exposure to interest rate variability on its outstanding floating-rate debt. The Company has not designated, for accounting purposes, its interest rate swap as a cash flow hedge of its U.S. Dollar LIBOR-denominated borrowings. In January 2020, the Company completed a refinancing of certain long-term debt facilities (note 6). As a result of this refinancing, the Company extinguished all of its then existing interest rate swaps. In March 2020, the Company entered into a new interest rate swap which is scheduled to mature in December 2024. The following summarizes the Company's interest rate swap agreement as at September 30, 2020: Interest Rate Notional Amount Fair Value /Carrying Amount of Liability Remaining Term Fixed Swap Rate Index $ $ (years) (%) (1) LIBOR-Based Debt: U.S. Dollar-denominated interest rate swap agreement LIBOR 50,000 (989) 4.3 0.76 (1) Excludes the margin the Company pays on its variable-rate long-term debt, which, as of September 30, 2020, ranged from 2.25% to 2.40%. The Company is potentially exposed to credit loss in the event of non-performance by the counterparty to the interest rate swap agreements in the event that the fair value results in an asset being recorded. In order to minimize counterparty risk, the Company only enters into interest rate swap agreements with counterparties that are rated A– or better by Standard & Poor’s or A3 or better by Moody’s at the time transactions are entered into. Forward freight agreements The Company uses forward freight agreements (or FFAs ) in non-hedge-related transactions to increase or decrease its exposure to spot market rates, within defined limits. Net gains and losses from FFAs are recorded within realized and unrealized (loss) gain on derivative instruments in the Company's unaudited consolidated statements of (loss) income. The following table presents the location and fair value amounts of derivative instruments, segregated by type of contract, on the Company’s unaudited consolidated balance sheets. Current portion of derivative assets Derivative assets Accounts receivable Current portion of derivative liabilities Derivative liabilities $ $ $ $ $ As at September 30, 2020 Interest rate swap agreement — — — (272) (717) Forward freight agreements — — — (483) — — — — (755) (717) As at December 31, 2019 Interest rate swap agreements 577 82 230 — — Forward freight agreements — — — (86) — 577 82 230 (86) — Realized and unrealized gains (losses) relating to the interest rate swaps and FFAs are recognized in earnings and reported in realized and unrealized (loss) gain on derivative instruments in the Company’s unaudited consolidated statements of (loss) income as follows: Three Months Ended Three Months Ended September 30, 2020 September 30, 2019 Realized losses Unrealized gains (losses) Total Realized gains Unrealized (losses) gains Total $ $ $ $ $ $ Interest rate swap agreements (58) 49 (9) 613 (541) 72 Forward freight agreements (184) (221) (405) 435 946 1,381 (242) (172) (414) 1,048 405 1,453 Nine Months Ended Nine Months Ended September 30, 2020 September 30, 2019 Realized gains (losses) Unrealized losses Total Realized gains Unrealized (losses) gains Total $ $ $ $ $ $ Interest rate swap agreements 551 (1,648) (1,097) 2,395 (5,010) (2,615) Forward freight agreements (433) (300) (733) 393 1,050 1,443 118 (1,948) (1,830) 2,788 (3,960) (1,172)

Other Income

Other Income	9 Months Ended
	Sep. 30, 2020
Other Nonoperating Income [Abstract]
Other Nonoperating Income and Expense [Text Block]	Other (Expense) Income The components of other (expense) income are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2020 2019 2020 2019 $ $ $ $ Foreign exchange (loss) gain (514) 918 534 1,100 Other income 44 15 1,079 82 Total (470) 933 1,613 1,182

Freight Tax and Other Tax Expen

Freight Tax and Other Tax Expense	9 Months Ended
	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income Tax Disclosure	Income Tax (Expense) Recovery The following table reflects changes in uncertain tax positions relating to freight tax liabilities, which are recorded in other long-term liabilities and accrued liabilities on the Company's unaudited consolidated balance sheets: Nine Months Ended 30 September 2020 2019 Balance of unrecognized tax benefits as at January 1 49,579 32,059 Increases for positions related to the current year 2,290 2,067 Changes for positions taken in prior years (12,968) 2,114 Settlements with tax authority (8,556) — Decreases related to statute of limitations (961) — Balance of unrecognized tax benefits as at September 30 29,384 36,240 Included in the Company's current income tax expense are provisions for uncertain tax positions relating to freight taxes. In the nine months ended September 30, 2020, the Company obtained further legal advice regarding the applicable tax rate in respect of freight taxes in a certain jurisdiction and subsequently secured an agreement in principle with a tax authority relating to an outstanding uncertain tax liability. The agreement in principle was based in part on an initiative of the tax authority in response to the COVID-19 global pandemic, which included the waiver of interest and penalties on unpaid taxes. Based on this and other clarifications of tax regulations, the Company reversed $15.2 million of freight tax liabilities as at June 30, 2020. In August 2020, the Company made a tax payment of $7.7 million to this jurisdiction with respect to open tax years up to and including 2019, with the remaining balance of tax accrual for 2020 recorded in accrued liabilities on the Company's unaudited consolidated balance sheet as of September 30, 2020. The Company does not presently anticipate that its provisions for these uncertain tax positions will significantly increase in the next 12 months; however, this is dependent on the jurisdictions in which vessel trading activity occurs. The Company reviews its freight tax obligations on a regular basis and may update its assessment of its tax positions based on available information at that time. Such information may include legal advice as to applicability of freight taxes in relevant jurisdictions. Freight tax regulations are subject to change and interpretation; therefore, the amounts recorded by the Company may change accordingly.

Financial Instruments

Financial Instruments	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Financial Instruments	Financial Instruments Fair Value Measurements For a description of how the Company estimates fair value and for a description of the fair value hierarchy levels, see Item 18 - Financial Statements: Note 14 to the Company’s audited consolidated financial statements filed with its Annual Report on Form 20-F for the year ended December 31, 2019. The following table includes the estimated fair value and carrying value of those assets and liabilities that are measured at fair value on a recurring and non-recurring basis, as well as the estimated fair value of the Company’s financial instruments that are not accounted for at the fair value on a recurring basis. September 30, 2020 December 31, 2019 Fair Value Hierarchy Level Carrying Amount Asset / (Liability) $ Fair Value Asset / (Liability) $ Carrying Amount Asset / (Liability) $ Fair Value Asset / (Liability) $ Recurring: Cash, cash equivalents and restricted cash Level 1 128,995 128,995 95,332 95,332 Derivative instruments (note 8) Interest rate swap agreements (1) Level 2 (989) (989) 659 659 Forward freight agreements (1) Level 2 (483) (483) (86) (86) Non-recurring: Operating lease right-of-use assets ( note 15) Level 2 6,148 6,148 — — Vessels and equipment (3) ( note 15 ) Level 2 46,750 46,750 — — Vessels related to finance leases (3) ( note 15 ) Level 2 34,000 34,000 — — Other: Short-term debt (note 5) Level 2 (20,000) (19,994) (50,000) (50,000) Advances to equity-accounted joint venture (2) 5,280 (2) 9,930 (2) Long-term debt, including current portion (note 6) Level 2 (222,375) (219,271) (559,679) (558,657) Obligations related to finance leases, including current portion (note 7) Level 2 (396,072) (465,342) (414,788) (442,648) Assets held for sale ( note 15 ) Level 2 — — 37,240 37,240 (1) The fair value of the Company’s interest rate swap agreements and FFAs at September 30, 2020 and December 31, 2019 exclude accrued interest income and expenses which are recorded in accounts receivable and accrued liabilities, respectively, on the unaudited consolidated balance sheets. (2) The advances to its equity-accounted joint venture, together with the Company’s investment in the equity-accounted joint venture, form the net aggregate carrying value of the Company’s interests in the equity-accounted joint venture in these unaudited consolidated financial statements. The fair values of the individual components of such aggregate interests as at September 30, 2020 and December 31, 2019 were not determinable.

Capital Stock and Stock-Based C

Capital Stock and Stock-Based Compensation	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Capital Stock and Stock-Based Compensation	Capital Stock and Equity-Based Compensation The authorized capital stock of the Company at September 30, 2020 was 100.0 million shares of Preferred Stock (December 31, 2019 - 100.0 million shares), with a par value of $0.01 per share (December 31, 2019 - $0.01 per share), 485.0 million shares of Class A common stock (December 31, 2019 - 485.0 million shares), with a par value of $0.01 per share (December 31, 2019 - $0.01 per share), and 100.0 million shares of Class B common stock (December 31, 2019 - 100.0 million shares), with a par value of $0.01 per share (December 31, 2019 - $0.01 per share). A share of Class A common stock entitles the holder to one vote per share while a share of Class B common stock entitles the holder to five votes per share, subject to a 49% aggregate Class B common stock voting power maximum. As of September 30, 2020, the Company had 29.1 million shares of Class A common stock (December 31, 2019 – 29.0 million), 4.6 million shares of Class B common stock (December 31, 2019 – 4.6 million) and no shares of preferred stock (December 31, 2019 – nil) issued and outstanding. During the three and nine months ended September 30, 2020, the Company recorded $0.4 million and $1.3 million (2019 - $0.2 million and $0.9 million), respectively, of expenses related to restricted stock units and stock options in general and administrative expenses. During the nine months ended September 30, 2020, a total of 78.3 thousand restricted stock units (2019 - 53.8 thousand) with a market value of $1.3 million (2019 - $0.5 million) vested and were paid to the grantees by issuing 44.8 thousand shares (2019 - 34.1 thousand shares) of Class A common stock, net of withholding taxes.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2020
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Management Fee - Related and Other a. The Company's operations are conducted in part by its subsidiaries, which receive services from Teekay's wholly-owned subsidiary, Teekay Shipping Ltd. (or the Manager ) and its affiliates. The Manager provides various services under a long-term management agreement (the Management Agreement ). Commencing October 1, 2018, the Company elected to receive vessel management services for its owned and leased vessels (other than certain former Tanker Investments Ltd. (or TIL ) vessels, which are technically managed by a third party) from its wholly-owned subsidiaries and no longer contracts these services from the Manager. b. Amounts received and (paid) by the Company for related party transactions for the periods indicated were as follows: Three Months Ended Nine Months Ended September 30, 2020 September 30, 2019 September 30, 2020 September 30, 2019 $ $ $ $ Vessel operating expenses - technical management fee (i) (248) — (744) — Strategic and administrative service fees (ii) (7,453) (7,437) (22,568) (23,179) Secondment fees (iii) (95) (21) (337) (120) LNG service revenues (iv) — (150) — 1,979 Technical management fee revenue (v) 169 169 507 596 Service revenues (vi) 3 100 12 317 (i) The cost of ship management services provided by a third party has been presented as vessel operating expenses on the Company's unaudited consolidated statements of (loss) income. The Company paid such third party technical management fees to the Manager in relation to certain former TIL vessels. (ii) The Manager’s strategic and administrative service fees have been presented in general and administrative expenses, except for fees related to technical management services, which have been presented in vessel operating expenses on the Company’s unaudited consolidated statements of (loss) income. The Company’s executive officers are employees of Teekay or subsidiaries thereof, and their compensation (other than any awards under the Company’s long-term incentive plan) is set and paid by Teekay or such other subsidiaries. The Company compensates Teekay for time spent by its executive officers on the Company’s management matters through the strategic portion of the management fee. (iii) The Company pays secondment fees for services provided by some employees of Teekay. Secondment fees have been presented in general and administrative expenses, except for fees related to technical management services, which have been presented in vessel operating expenses on the Company's unaudited consolidated statements of (loss) income. (iv) In November 2016, the Company's ship-to-ship transfer business signed an operational and maintenance subcontract with Teekay LNG Bahrain Operations L.L.C., an entity wholly-owned by Teekay LNG Partners L.P., for the Bahrain LNG Import Terminal. The terminal is owned by Bahrain LNG W.I.L., a joint venture for which Teekay LNG Operating L.L.C., an entity wholly-owned by Teekay LNG Partners L.P., has a 30% interest. The sub-contract ended in April 2019. (v) The Company receives reimbursements from Teekay for the provision of technical management services. These reimbursements have been presented in general and administrative expenses on the Company's unaudited consolidated statements of (loss) income. (vi) The Company recorded service revenues relating to Teekay Tanker Operations Limited's (or TTOL) administration of certain revenue sharing agreements and provision of certain commercial services to the counterparties in the agreements. c. The Manager and other subsidiaries of Teekay collect revenues and remit payments for expenses incurred by the Company’s vessels. Such amounts, which are presented on the Company’s unaudited consolidated balance sheets in "due from affiliates" or "due to affiliates," as applicable, are without interest or stated terms of repayment. In addition, $12.2 million and $7.9 million were payable as crewing and manning costs as at September 30, 2020 and December 31, 2019, respectively, and such amounts are included in accrued liabilities in the unaudited consolidated balance sheets. These crewing and manning costs will be payable as reimbursement to the Manager once they are paid by the Manager to the vessels' crew. d. In October 2018, the Company established a new RSA structure under TTCL and subsequently began transitioning the Company's RSA activities from TTOL to TTCL. Pursuant to a service agreement with the Teekay Aframax RSA prior to the change in structure, from time to time, the Company hired vessels to perform full service lightering services. During the three and nine months ended September 30, 2019, the Company recognized nil and $2.0 million, respectively, related to vessels that were chartered-in from the RSA to assist with full service lightering operations. These amounts have been presented in voyage expenses on the Company's unaudited consolidated statements of (loss) income.

Earnings (Loss) Per Share

Earnings (Loss) Per Share	9 Months Ended
	Sep. 30, 2020
Earnings Per Share [Abstract]
Loss Per Share	4. (Loss) Earnings Per Share The net (loss) earnings available for common shareholders and (loss) earnings per common share are presented in the table below: Three Months Ended Nine Months Ended September 30, 2020 September 30, 2019 September 30, 2020 September 30, 2019 $ $ Net (loss) income (44,434) (19,850) 160,603 (21,710) Weighted average number of common shares - basic 33,738,143 33,623,608 33,712,124 33,610,936 Dilutive effect of stock-based awards — — 230,067 — Weighted average number of common shares - diluted 33,738,143 33,623,608 33,942,191 33,610,936 (Loss) earnings per common share: – Basic (1.32) (0.59) 4.76 (0.65) – Diluted (1.32) (0.59) 4.73 (0.65) Stock-based awards that have an anti-dilutive effect on the calculation of diluted earnings per common share are excluded from this calculation. In the periods where a loss attributable to shareholders has been incurred, all stock-based awards are anti-dilutive. For the three and nine months ended September 30, 2020, 0.2 million and 0.1 million restricted stock units, respectively, had anti-dilutive effects on the calculation of diluted earnings per common share. For the three and nine months ended September 30, 2020, options to acquire 0.2 million shares of the Company’s Class A common stock had anti-dilutive effects on the calculation of diluted earnings per common share.

Sale of Assets

Sale of Assets	9 Months Ended
	Sep. 30, 2020
Property, Plant and Equipment [Abstract]
Sale of Vessels and Other Assets [Text Block]	The Company's unaudited consolidated statements of (loss) income for the nine months ended September 30, 2020 includes a gain of $3.1 million relating to the completion of the sale of the non-US portion of its ship-to-ship support services business, as well as its LNG terminal management business for proceeds of $27.1 million, including an adjustment of $1.1 million for the final amounts of cash and other working capital present on the closing date. Of the total proceeds, $14.3 million was received in May 2020 and the remaining $12.7 million was received in July 2020. During the nine months ended September 30, 2020, the Company completed the sale of three Suezmax tankers, two of which were classified as held for sale on the Company's unaudited consolidated balance sheet as at December 31, 2019, with an aggregate loss on sales of $2.6 million.
Asset Impairment Charges	Write-down and Sale of Assets During the three and nine months ended September 30, 2020, the carrying values of five Aframax tankers were written down to their estimated fair values, using appraised values, primarily due to the lower near-term tanker market outlook, a reduction of charter rates, and a decline in vessel values, as a result of the current economic environment, which has been impacted by the COVID-19 global pandemic. The Company's consolidated statements of (loss) income for the three and nine months ended September 30, 2020 include a $43.5 million write-down related to these vessels. During the three and nine months ended September 30, 2020, the Company recorded write-downs of $1.4 million and $2.1 million, respectively, on its operating lease right-of-use assets, which were written-down to their estimated fair value, based on prevailing charter rates for comparable periods, due to a reduction in these charter rates.

Restructuring and Related Activ

Restructuring and Related Activities	9 Months Ended
	Sep. 30, 2020
Restructuring and Related Activities [Abstract]
Restructuring and Related Activities Disclosure	Restructuring Charge During the three and nine months ended September 30, 2020, the Company recognized restructuring charges of $1.4 million. The restructuring charges relate to estimated severance costs resulting from organizational changes to the Company's tanker services and operations, partially related to the sale of the non-US portion of the Company's ship-to-ship support services business in April 2020 (note 15). As at September 30, 2020 and December 31, 2019, restructuring liabilities of $1.4 million and nil, respectively, were recognized in accrued liabilities on the unaudited consolidated balance sheets.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2020
Subsequent Events [Abstract]
Subsequent Events [Text Block]	Subsequent Events On October 19 and 22, 2020, the Company completed the purchases of two Aframax tankers previously under the sale-leaseback arrangement described in note 7 for a total cost of $29.6 million, using available cash. On November 13, 2020, the Company declared purchase options to acquire two Suezmax tankers for a total cost of $56.7 million, as part of the repurchase options under the sale-leaseback arrangements described in note 7. The Company expects to complete the purchase and delivery of these vessels in May 2021.

Accounting Policies (Policies)

Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2020
Accounting Policies [Abstract]
New Accounting Pronouncements, Policy	Recent Accounting Pronouncements In June 2016, the Financial Accounting Standards Board (or FASB) issued Accounting Standards Update 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments (or ASU 2016-13) . ASU 2016-13 introduces a new credit loss methodology, which requires earlier recognition of potential credit losses, while also providing additional transparency about credit risk. This new credit loss methodology utilizes a lifetime "expected credit loss" measurement objective for the recognition of credit losses for loans, held-to-maturity debt securities and other receivables at the time the financial asset is originated or acquired. The expected credit losses are subsequently adjusted each period for changes in expected lifetime credit losses. This methodology replaces multiple existing impairment methods under previous GAAP for these types of assets, which generally required that a loss be incurred before it was recognized. The Company adopted this update on January 1, 2020. The adoption of ASU 2016-13 did not have a material impact on the Company's unaudited consolidated financial statements. In December 2019, the FASB issued ASU 2019-12 - Income Taxes (Topic 740) Simplifying the Accounting for Income Taxes (or ASU 2019-12) , as part of its initiative to reduce complexity in the accounting standards. The amendments in ASU 2019-12 eliminate certain exceptions related to the approach for intraperiod tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences, among other changes. The guidance becomes effective for annual reporting periods beginning after December 15, 2020 and interim periods within those fiscal years with early adoption permitted. The Company is currently evaluating the effect of adopting this new guidance. In March 2020, the FASB issued ASU 2020-04 - Reference Rate Reform (Topic 848) Facilitation of the Effects of Reference Rate Reform on Financial Reporting ( or ASU 2020-04) . This ASU provides optional guidance for a limited period of time to ease potential accounting impacts associated with transitioning away from reference rates that are expected to be discontinued, such as the London Interbank Offered Rate (or LIBOR ). The amendments in this ASU apply only to contracts, hedging relationships, and other transactions that reference LIBOR or another reference rate expected to be discontinued. The amendments in this ASU are effective through December 31, 2022. The Company is currently evaluating the effect of adopting this new guidance.

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 30, 2020
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following table contains a breakdown of the Company's revenue by contract type for the three and nine months ended September 30, 2020 and September 30, 2019. All revenue is part of the Company's tanker segment, except for revenue for the non-US portion of the ship-to-ship support services and LNG terminal management, consultancy, procurement, and other related services, which are part of the Company's previously existing ship-to-ship transfer segment. The Company’s lease income consists of the revenue from its voyage charters and time-charters. Three Months Ended September 30, Nine Months Ended September 30, 2020 2019 2020 2019 $ $ $ $ Voyage charter revenues Suezmax 51,134 87,963 302,839 276,972 Aframax 38,847 52,845 170,680 167,981 LR2 17,007 24,759 93,666 86,711 Full service lightering 18,831 12,607 84,038 60,082 Total 125,819 178,174 651,223 591,746 Time-charter revenues Suezmax 35,133 1,909 81,700 4,978 Aframax 4,725 — 6,883 1,837 LR2 2,322 — 4,150 — Total 42,180 1,909 92,733 6,815 Other revenues Ship-to-ship support services 777 4,649 8,619 17,810 Commercial management 1,464 1,893 5,665 6,219 LNG terminal management, consultancy, procurement and other — 819 392 10,022 Total 2,241 7,361 14,676 34,051 Total revenues 170,240 187,444 758,632 632,612

Segment Reporting (Tables)

Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Schedule of Company's Revenue and Income from Operations by Segment	The following tables include results for the Company’s revenues and (loss) income from operations by segment for the nine months ended September 30, 2020 and three and nine months ended September 30, 2019. No results are included for the three months ended September 30, 2020 as the Company only had one reportable segment during that period. Three Months Ended September 30, 2019 Tanker Segment Ship-to-Ship Transfer Segment Total $ $ $ Revenues (1) 182,429 5,015 187,444 Voyage expenses (92,866) — (92,866) Vessel operating expenses (44,322) (4,217) (48,539) Time-charter hire expenses (10,637) — (10,637) Depreciation and amortization (30,806) (730) (31,536) General and administrative expenses (2) (8,380) (359) (8,739) Loss from operations (4,582) (291) (4,873) Equity income 68 — 68 Nine Months Ended September 30, 2020 Tanker Segment Ship-to-Ship Transfer Segment Total $ $ $ Revenues (1) 751,640 6,992 758,632 Voyage expenses (238,576) — (238,576) Vessel operating expenses (137,263) (5,940) (143,203) Time-charter hire expenses (28,245) — (28,245) Depreciation and amortization (88,677) (493) (89,170) General and administrative expenses (2) (28,330) (627) (28,957) (Loss) gain on sale of assets and write-down of assets (48,245) 3,081 (45,164) Restructuring charge (1,398) — (1,398) Income from operations 180,906 3,013 183,919 Equity income 5,174 — 5,174 Nine Months Ended September 30, 2019 Tanker Segment Ship-to-Ship Transfer Segment Total $ $ $ Revenues (1) 608,815 23,797 632,612 Voyage expenses (293,263) — (293,263) Vessel operating expenses (137,461) (19,265) (156,726) Time-charter hire expenses (30,877) — (30,877) Depreciation and amortization (89,921) (2,138) (92,059) General and administrative expenses (2) (26,295) (1,117) (27,412) Income from operations 30,998 1,277 32,275 Equity income 652 — 652
Reconciliation of Total Segment Assets to Total Assets Presented in Consolidated Balance Sheets	A reconciliation of total segment assets to total assets presented in the accompanying unaudited consolidated balance sheet as at December 31, 2019, when the Company had more than one reportable segment, is as follows: As at December 31, 2019 $ Tanker 2,114,451 Ship-to-Ship Transfer 26,201 Cash and cash equivalents 88,824 Consolidated total assets 2,229,476

Long-Term Debt (Tables)

Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Summary of Long-Term Debt	As at As at September 30, 2020 December 31, 2019 $ $ Revolving Credit Facilities due through 2024 155,000 341,132 Term Loans due through 2023 67,375 221,729 Total principal 222,375 562,861 Less: unamortized discount and debt issuance costs (7,310) (3,182) Total debt 215,065 559,679 Less: current portion (10,962) (43,573) Long-term portion 204,103 516,106

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Schedule of Future Minimum Lease Payments for Finance Leases [Table Text Block]	As at September 30, 2020, the Company's total remaining commitments related to the financial liabilities of these vessels were approximately $559.7 million (December 31, 2019 - $601.7 million), including imputed interest of $163.6 million (December 31, 2019 - $186.9 million), repayable from 2020 through 2030, as indicated below: Commitments Year September 30, 2020 Remainder of 2020 14,235 2021 56,222 2022 56,213 2023 56,204 2024 56,348 Thereafter 320,481
Obligations Related to Finance Leases [Table Text Block]	As at As at September 30, 2020 December 31, 2019 $ $ Total obligations related to finance leases 396,072 414,788 Less: current portion (26,794) (25,357) Long-term obligations related to finance leases 369,278 389,431

Derivative Instruments (Tables)

Derivative Instruments (Tables)	9 Months Ended
	Sep. 30, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of Interest Rate Swap Positions	The following summarizes the Company's interest rate swap agreement as at September 30, 2020: Interest Rate Notional Amount Fair Value /Carrying Amount of Liability Remaining Term Fixed Swap Rate Index $ $ (years) (%) (1) LIBOR-Based Debt: U.S. Dollar-denominated interest rate swap agreement LIBOR 50,000 (989) 4.3 0.76 (1) Excludes the margin the Company pays on its variable-rate long-term debt, which, as of September 30, 2020, ranged from 2.25% to 2.40%.
Schedule of Derivative Instruments	The following table presents the location and fair value amounts of derivative instruments, segregated by type of contract, on the Company’s unaudited consolidated balance sheets. Current portion of derivative assets Derivative assets Accounts receivable Current portion of derivative liabilities Derivative liabilities $ $ $ $ $ As at September 30, 2020 Interest rate swap agreement — — — (272) (717) Forward freight agreements — — — (483) — — — — (755) (717) As at December 31, 2019 Interest rate swap agreements 577 82 230 — — Forward freight agreements — — — (86) — 577 82 230 (86) —
Schedule of Other Derivatives Not Designated as Hedging Instruments, Statements of Financial Performance and Financial Position, Location	Realized and unrealized gains (losses) relating to the interest rate swaps and FFAs are recognized in earnings and reported in realized and unrealized (loss) gain on derivative instruments in the Company’s unaudited consolidated statements of (loss) income as follows: Three Months Ended Three Months Ended September 30, 2020 September 30, 2019 Realized losses Unrealized gains (losses) Total Realized gains Unrealized (losses) gains Total $ $ $ $ $ $ Interest rate swap agreements (58) 49 (9) 613 (541) 72 Forward freight agreements (184) (221) (405) 435 946 1,381 (242) (172) (414) 1,048 405 1,453 Nine Months Ended Nine Months Ended September 30, 2020 September 30, 2019 Realized gains (losses) Unrealized losses Total Realized gains Unrealized (losses) gains Total $ $ $ $ $ $ Interest rate swap agreements 551 (1,648) (1,097) 2,395 (5,010) (2,615) Forward freight agreements (433) (300) (733) 393 1,050 1,443 118 (1,948) (1,830) 2,788 (3,960) (1,172)

Other Income (Tables)

Other Income (Tables)	9 Months Ended
	Sep. 30, 2020
Other Nonoperating Income [Abstract]
Schedule of Other Nonoperating Income (Expense) [Table Text Block]	The components of other (expense) income are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2020 2019 2020 2019 $ $ $ $ Foreign exchange (loss) gain (514) 918 534 1,100 Other income 44 15 1,079 82 Total (470) 933 1,613 1,182

Freight Tax and Other Tax Exp_2

Freight Tax and Other Tax Expense (Tables)	9 Months Ended
	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Summary of Income Tax Contingencies	The following table reflects changes in uncertain tax positions relating to freight tax liabilities, which are recorded in other long-term liabilities and accrued liabilities on the Company's unaudited consolidated balance sheets: Nine Months Ended 30 September 2020 2019 Balance of unrecognized tax benefits as at January 1 49,579 32,059 Increases for positions related to the current year 2,290 2,067 Changes for positions taken in prior years (12,968) 2,114 Settlements with tax authority (8,556) — Decreases related to statute of limitations (961) — Balance of unrecognized tax benefits as at September 30 29,384 36,240

Financial Instruments (Tables)

Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Summary of Fair Value and Carrying Value of Assets and Liabilities Measured on Recurring and Non-recurring Basis	The following table includes the estimated fair value and carrying value of those assets and liabilities that are measured at fair value on a recurring and non-recurring basis, as well as the estimated fair value of the Company’s financial instruments that are not accounted for at the fair value on a recurring basis. September 30, 2020 December 31, 2019 Fair Value Hierarchy Level Carrying Amount Asset / (Liability) $ Fair Value Asset / (Liability) $ Carrying Amount Asset / (Liability) $ Fair Value Asset / (Liability) $ Recurring: Cash, cash equivalents and restricted cash Level 1 128,995 128,995 95,332 95,332 Derivative instruments (note 8) Interest rate swap agreements (1) Level 2 (989) (989) 659 659 Forward freight agreements (1) Level 2 (483) (483) (86) (86) Non-recurring: Operating lease right-of-use assets ( note 15) Level 2 6,148 6,148 — — Vessels and equipment (3) ( note 15 ) Level 2 46,750 46,750 — — Vessels related to finance leases (3) ( note 15 ) Level 2 34,000 34,000 — — Other: Short-term debt (note 5) Level 2 (20,000) (19,994) (50,000) (50,000) Advances to equity-accounted joint venture (2) 5,280 (2) 9,930 (2) Long-term debt, including current portion (note 6) Level 2 (222,375) (219,271) (559,679) (558,657) Obligations related to finance leases, including current portion (note 7) Level 2 (396,072) (465,342) (414,788) (442,648) Assets held for sale ( note 15 ) Level 2 — — 37,240 37,240 (1) The fair value of the Company’s interest rate swap agreements and FFAs at September 30, 2020 and December 31, 2019 exclude accrued interest income and expenses which are recorded in accounts receivable and accrued liabilities, respectively, on the unaudited consolidated balance sheets. (2) The advances to its equity-accounted joint venture, together with the Company’s investment in the equity-accounted joint venture, form the net aggregate carrying value of the Company’s interests in the equity-accounted joint venture in these unaudited consolidated financial statements. The fair values of the individual components of such aggregate interests as at September 30, 2020 and December 31, 2019 were not determinable. (3) In September 2020, the carrying values of five Aframax tankers were written down to their estimated fair values, using appraised values, primarily due to the lower near-term tanker market outlook, a reduction of charter rates, and a decline in vessel values, as a result of the current economic environment, which has been impacted by the COVID-19 global pandemic. Three of these vessels were classified as vessels and equipment and two were classified as vessels related to finance leases on the Company's unaudited consolidated balance sheet as at September 30, 2020.

Related Party Transactions (Tab

Related Party Transactions (Tables)	9 Months Ended
	Sep. 30, 2020
Related Party Transactions [Abstract]
Summary of Related Party Transactions	Three Months Ended Nine Months Ended September 30, 2020 September 30, 2019 September 30, 2020 September 30, 2019 $ $ $ $ Vessel operating expenses - technical management fee (i) (248) — (744) — Strategic and administrative service fees (ii) (7,453) (7,437) (22,568) (23,179) Secondment fees (iii) (95) (21) (337) (120) LNG service revenues (iv) — (150) — 1,979 Technical management fee revenue (v) 169 169 507 596 Service revenues (vi) 3 100 12 317 (i) The cost of ship management services provided by a third party has been presented as vessel operating expenses on the Company's unaudited consolidated statements of (loss) income. The Company paid such third party technical management fees to the Manager in relation to certain former TIL vessels. (ii) The Manager’s strategic and administrative service fees have been presented in general and administrative expenses, except for fees related to technical management services, which have been presented in vessel operating expenses on the Company’s unaudited consolidated statements of (loss) income. The Company’s executive officers are employees of Teekay or subsidiaries thereof, and their compensation (other than any awards under the Company’s long-term incentive plan) is set and paid by Teekay or such other subsidiaries. The Company compensates Teekay for time spent by its executive officers on the Company’s management matters through the strategic portion of the management fee. (iii) The Company pays secondment fees for services provided by some employees of Teekay. Secondment fees have been presented in general and administrative expenses, except for fees related to technical management services, which have been presented in vessel operating expenses on the Company's unaudited consolidated statements of (loss) income. (iv) In November 2016, the Company's ship-to-ship transfer business signed an operational and maintenance subcontract with Teekay LNG Bahrain Operations L.L.C., an entity wholly-owned by Teekay LNG Partners L.P., for the Bahrain LNG Import Terminal. The terminal is owned by Bahrain LNG W.I.L., a joint venture for which Teekay LNG Operating L.L.C., an entity wholly-owned by Teekay LNG Partners L.P., has a 30% interest. The sub-contract ended in April 2019. (v) The Company receives reimbursements from Teekay for the provision of technical management services. These reimbursements have been presented in general and administrative expenses on the Company's unaudited consolidated statements of (loss) income.

Earnings (Loss) Per Share (Tabl

Earnings (Loss) Per Share (Tables)	9 Months Ended
	Sep. 30, 2020
Earnings Per Share [Abstract]
Basic and Diluted (Loss) Earnings Per Share	The net (loss) earnings available for common shareholders and (loss) earnings per common share are presented in the table below: Three Months Ended Nine Months Ended September 30, 2020 September 30, 2019 September 30, 2020 September 30, 2019 $ $ Net (loss) income (44,434) (19,850) 160,603 (21,710) Weighted average number of common shares - basic 33,738,143 33,623,608 33,712,124 33,610,936 Dilutive effect of stock-based awards — — 230,067 — Weighted average number of common shares - diluted 33,738,143 33,623,608 33,942,191 33,610,936 (Loss) earnings per common share: – Basic (1.32) (0.59) 4.76 (0.65) – Diluted (1.32) (0.59) 4.73 (0.65)

Basis of Presentation Basis of

Basis of Presentation Basis of Presentation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Total revenues	$ 170,240	$ 187,444	$ 758,632	$ 632,612
Cost of Goods and Services Sold	57,777	92,866	238,576	293,263
Voyage charter revenues
Total revenues	$ 125,819	178,174	$ 651,223	591,746
Restatement Adjustment [Member] | Voyage charter revenues
Total revenues		5,100		15,500
Restatement Adjustment [Member] | Reimbursement of vessel operating expenses [Domain]
Cost of Goods and Services Sold		$ 5,100		$ 15,500

Revenue Revenue - Narrative (De

Revenue Revenue - Narrative (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020USD ($)vessel	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)contractvessel	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)vessel
Disaggregation of Revenue [Line Items]
Number of forms of contracts | contract			2
Total revenues	$ 170,240	$ 187,444	$ 758,632	$ 632,612
Lessor, Operating Lease, Payments to be Received, Remainder of Fiscal Year	31,600		31,600
Operating leases, future minimum payments receivable					$ 40,000
Operating Leases, Future Minimum Payments Receivable, in Three Years	41,700		41,700
Lessor, Operating Lease, Payments to be Received, Three Years	$ 5,200		$ 5,200
Charters Out Expires 2022 [Domain]
Disaggregation of Revenue [Line Items]
Number Of Vessels | vessel	2		2
Charters Out Expires 2021 [Domain]
Disaggregation of Revenue [Line Items]
Number Of Vessels | vessel	6		6
Charters Out Expires 2020 [Member] [Domain]
Disaggregation of Revenue [Line Items]
Number Of Vessels | vessel	3		3
Charters Out
Disaggregation of Revenue [Line Items]
Number Of Vessels | vessel	11		11		5
Time-charter [Member]
Disaggregation of Revenue [Line Items]
Total revenues	$ 42,180	$ 1,909	$ 92,733	$ 6,815
Contract with Customer, Liability, Current	$ 3,100		$ 3,100		$ 7,500

Revenue Revenue - Disaggregatio

Revenue Revenue - Disaggregation of revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Total revenues	$ 170,240	$ 187,444	$ 758,632	$ 632,612
Voyage Charters - Suezmax
Disaggregation of Revenue [Line Items]
Total revenues	51,134	87,963	302,839	276,972
Voyage Charters - Aframax
Disaggregation of Revenue [Line Items]
Total revenues	38,847	52,845	170,680	167,981
Voyage Charters - LR2
Disaggregation of Revenue [Line Items]
Total revenues	17,007	24,759	93,666	86,711
Voyage Charters - Full Service Lightering
Disaggregation of Revenue [Line Items]
Total revenues	18,831	12,607	84,038	60,082
Voyage charter revenues
Disaggregation of Revenue [Line Items]
Total revenues	125,819	178,174	651,223	591,746
Time Charters - Aframax
Disaggregation of Revenue [Line Items]
Total revenues	4,725	0	6,883	1,837
Time Charters - Suezmax
Disaggregation of Revenue [Line Items]
Total revenues	35,133	1,909	81,700	4,978
Time Charters - LR2
Disaggregation of Revenue [Line Items]
Total revenues	2,322	0	4,150	0
Time-charter [Member]
Disaggregation of Revenue [Line Items]
Total revenues	42,180	1,909	92,733	6,815
Ship-to-ship support services, Other revenue
Disaggregation of Revenue [Line Items]
Total revenues	777	4,649	8,619	17,810
Commercial management, Other revenue
Disaggregation of Revenue [Line Items]
Total revenues	1,464	1,893	5,665	6,219
LNG terminal management, consultancy and other, Other revenue
Disaggregation of Revenue [Line Items]
Total revenues	0	819	392	10,022
Other revenues
Disaggregation of Revenue [Line Items]
Total revenues	$ 2,241	$ 7,361	$ 14,676	$ 34,051

Segment Reporting - Additional

Segment Reporting - Additional Information (Details) - segment	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Segment Reporting [Abstract]
Number of reportable segments	1	1

Segment Reporting - Schedule of

Segment Reporting - Schedule of Company's Revenue and Income From Operations by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Revenues	$ 170,240	$ 187,444	$ 758,632	$ 632,612
Voyage expenses	(57,777)	(92,866)	(238,576)	(293,263)
Vessel operating expenses	(46,336)	(48,539)	(143,203)	(156,726)
Time-charter hire expenses	9,070	10,637	28,245	30,877
Depreciation and amortization	(29,992)	(31,536)	(89,170)	(92,059)
General and administrative expenses	(9,887)	(8,739)	(28,957)	(27,412)
(Loss) gain on sale of assets and write-down of assets	(44,973)	0	(45,164)	0
Restructuring Charges	(1,398)	0	(1,398)	0
(Loss) income from operations	(29,193)	(4,873)	183,919	32,275
Equity income	$ 46	68	5,174	652
Operating Segments | Tanker
Segment Reporting Information [Line Items]
Revenues		182,429	751,640	608,815
Voyage expenses		(92,866)	(238,576)	(293,263)
Vessel operating expenses		(44,322)	(137,263)	(137,461)
Time-charter hire expenses		10,637	28,245	30,877
Depreciation and amortization		(30,806)	(88,677)	(89,921)
General and administrative expenses		(8,380)	(28,330)	(26,295)
(Loss) gain on sale of assets and write-down of assets			(48,245)
Restructuring Charges			(1,398)
(Loss) income from operations		(4,582)	180,906	30,998
Equity income		68	5,174	652
Operating Segments | Ship-to-Ship Transfer
Segment Reporting Information [Line Items]
Revenues		5,015	6,992	23,797
Voyage expenses		0	0	0
Vessel operating expenses		(4,217)	(5,940)	(19,265)
Time-charter hire expenses		0	0	0
Depreciation and amortization		(730)	(493)	(2,138)
General and administrative expenses		(359)	(627)	(1,117)
(Loss) gain on sale of assets and write-down of assets			3,081
Restructuring Charges			0
(Loss) income from operations		(291)	3,013	1,277
Equity income		$ 0	$ 0	$ 0

Segment Reporting - Reconciliat

Segment Reporting - Reconciliation of Total Segment Assets to Total Assets Presented in Consolidated Balance Sheets (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2020USD ($)segment	Dec. 31, 2019USD ($)segment	Sep. 30, 2019USD ($)	Dec. 31, 2018USD ($)
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated total assets	$ 1,912,004	$ 2,229,476
Cash and cash equivalents	$ 120,872	$ 88,824	$ 76,705	$ 54,917
Number of reportable segments | segment	1	1
Tanker
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated total assets		$ 2,114,451
Ship-to-Ship Transfer
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated total assets		$ 26,201

Short-Term Debt (Details)

Short-Term Debt (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019	Nov. 30, 2018
Short-term Debt [Line Items]
Short-term debt (note 5)	$ 20,000	$ 50,000
Short-term Debt, Weighted Average Interest Rate, at Point in Time	3.60%	5.00%
Short-term Debt [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 80,000	$ 40,000
Debt Instrument, Term	6 months
Minimum [Member]
Short-term Debt [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.25%
Debt Covenant, Required Capital Invested	$ 20,000
Maximum [Member]
Short-term Debt [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.40%
Debt Covenant, Required Capital Invested	$ 30,000
London Interbank Offered Rate (LIBOR) [Member]
Short-term Debt [Line Items]
Short-term Debt, Percentage Bearing Variable Interest Rate	3.50%

Long-Term Debt - Summary of Lon

Long-Term Debt - Summary of Long-Term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total principal	$ 222,375	$ 562,861
Less: unamortized discount and debt issuance costs	(7,310)	(3,182)
Total debt	215,065	559,679
Less: current portion	(10,962)	(43,573)
Long-term portion	204,103	516,106
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total principal	155,000	341,132
Term Loans
Debt Instrument [Line Items]
Total principal	$ 67,375	$ 221,729

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information - Revolvers and Term Loans (Details)	1 Months Ended		3 Months Ended	9 Months Ended	12 Months Ended
	Aug. 31, 2020USD ($)credit_facility	Jan. 31, 2020USD ($)credit_facility	Mar. 31, 2020credit_facility	Sep. 30, 2020USD ($)credit_facilityvessel	Dec. 31, 2019USD ($)credit_facility
Debt Instrument [Line Items]
Total principal				$ 222,375,000	$ 562,861,000
Repayments of Debt	$ 85,100,000	$ 455,300,000
Weighted-average effective interest rate				2.60%	3.70%
Aggregate annual long-term principal repayments, remainder of 2020				$ 2,800,000
Aggregate annual long-term principal repayments, 2021				11,200,000
Aggregate annual long-term principal repayments, 2022				11,200,000
Aggregate annual long-term principal repayments, 2023				42,200,000
Aggregate annual long-term principal repayments, 2024				$ 155,000,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Number Of Debt Instruments | credit_facility		2		1	2
Line of Credit Facility, Maximum Borrowing Capacity				$ 485,600,000	$ 371,500,000
Line of Credit Facility, Remaining Borrowing Capacity				330,600,000	30,400,000
Long-term Debt, Revolving Credit Facility, Decrease in Amount Available Remaining Fiscal Year				47,200,000
Long-term Debt, Revolving Credit Facility, Decrease in Amount Available Year Two				91,400,000
Long-term Debt, Revolving Credit Facility, Decrease in Amount Available Year Three				80,400,000
Long-term Debt, Revolving Credit Facility, Decrease in Amount Available Year Four				65,300,000
Long term Debt, Revolving Credit Facility Decrease in Amount Available Year Five				201,300,000
Total principal				$ 155,000,000	341,132,000
Term Loans
Debt Instrument [Line Items]
Number Of Debt Instruments | credit_facility	1	2	3	1
Total principal				$ 67,375,000	$ 221,729,000
Debt instrument, interest rate, stated percentage					5.40%
Term Loan Due 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Collateral, Number of Vessels | vessel				4
Debt Covenant Minimum Hull Coverage Ratio				125.00%
Actual Hull Coverage Ratio				182.00%
Minimum liquidity covenant requirement				$ 35,000,000
Minimum liquidity as a percentage of consolidated debt covenant requirement				5.00%
Term Loan Due 2023 [Member] | Term Loans
Debt Instrument [Line Items]
Total principal				$ 67,400,000
2020DebtFacilityMaturinginDecember2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Collateral, Number of Vessels | vessel				31
Actual Hull Coverage Ratio				483.00%
Minimum liquidity covenant requirement				$ 35,000,000
Minimum liquidity as a percentage of consolidated debt covenant requirement				5.00%
2020DebtFacilityMaturinginDecember2024 [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total principal				$ 155,000,000
Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				2.25%
Minimum [Member] | Term Loan Due 2023 [Member] | Term Loans
Debt Instrument [Line Items]
Long-term Debt, Term				6 months
Minimum [Member] | 2020DebtFacilityMaturinginDecember2024 [Member] | Term Loans
Debt Instrument [Line Items]
Long-term Debt, Term				6 months
Maximum
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				2.40%
London Interbank Offered Rate (LIBOR) [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				2.40%
London Interbank Offered Rate (LIBOR) [Member] | Term Loans
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				2.25%
London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate					2.00%
London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] | Term Loans
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate					0.30%
London Interbank Offered Rate (LIBOR) [Member] | Maximum | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate					2.75%
London Interbank Offered Rate (LIBOR) [Member] | Maximum | Term Loans
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate					2.00%

Leases Operating Leases (Detail

Leases Operating Leases (Details) $ in Millions	Sep. 30, 2020USD ($)
Operating Leased Assets [Line Items]
Operating Leases, Future Minimum Payments, Remainder of Fiscal Year	$ 8.9
Lessee, Operating Lease, Liability, Payments, Due Year Two	10.5
Lessee, Operating Lease, Liability, Payments, Due Year Three	$ 1.5

Leases Finance Lease Obligation

Leases Finance Lease Obligation (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Finance Leased Assets [Line Items]
Finance Lease, Liability	$ 396,072	$ 414,788
Current obligations related to finance leases (note 7)	26,794	25,357
Long-term obligations related to finance leases (note 7)	$ 369,278	$ 389,431

Leases - Additional Information

Leases - Additional Information (Details) $ in Thousands	1 Months Ended		9 Months Ended
	Nov. 30, 2020USD ($)	Oct. 31, 2020USD ($)	Sep. 30, 2020USD ($)vessel	Sep. 30, 2019USD ($)	Nov. 13, 2020vessel	Oct. 22, 2020vessel	Dec. 31, 2019
Finance Leased Assets [Line Items]
Number of vessels obligated to purchase			8
Finance Lease, Weighted Average Discount Rate, Percent			7.60%				7.60%
Payments to Acquire Property, Plant, and Equipment | $			$ 8,881	$ 7,210
Lessee, Finance Leases			Obligations Related to Finance Leases As at As at September 30, 2020 December 31, 2019 $ $ Total obligations related to finance leases 396,072 414,788 Less: current portion (26,794) (25,357) Long-term obligations related to finance leases 369,278 389,431 From 2017 to 2019, the Company completed sale-leaseback financing transactions with financial institutions relating to 16 of the Company's vessels. Under these arrangements, the Company transferred the vessels to subsidiaries of the financial institutions (collectively, the Lessors ) and leased the vessels back from the Lessors on bareboat charters ranging from 9- to 12-year terms. The Company is obligated to purchase eight of the vessels upon maturity of their respective bareboat charters. The Company also has the option to purchase each of the 16 vessels at various times starting between July 2020 and November 2021 until the end of their respective lease terms. In October 2020, the Company completed the purchases of two of these vessels for a total cost of $29.6 million and in November 2020, the Company declared purchase options to acquire two more of these vessels for a total cost of $56.7 million with an expected completion date of May 2021 (see note 19). The bareboat charters related to these vessels require that the Company maintain a minimum liquidity (cash, cash equivalents and undrawn committed revolving credit lines with at least six months to maturity) of $35.0 million and at least 5.0% of the Company's consolidated debt and obligations related to finance leases. Four bareboat charters, entered into in July 2017, require the Company to maintain, for each vessel, a minimum hull coverage ratio of 90% of the total outstanding principal balance during the first three years of the lease period and 100% of the total outstanding principal balance thereafter. As at September 30, 2020, these ratios ranged from 119% to 141% (December 31, 2019 - ranged from 110% to 132%). Six bareboat charters, entered into in September 2018, require the Company to maintain, for each vessel, a minimum hull coverage ratio of 75% of the total outstanding principal balance during the first year of the lease period, 78% for the second year, 80% for the following two years and 90% of the total outstanding principal balance thereafter. As at September 30, 2020, these ratios ranged from 87% to 104% (December 31, 2019 - ranged from 106% to 123%). Four bareboat charters, entered into in November 2018, require the Company to maintain, for each vessel, a minimum hull coverage ratio of 100% of the total outstanding principal balance. As at September 30, 2020, these ratios ranged from 113% to 156% (December 31, 2019 - ranged from 140% to 173%). Two bareboat charters, entered into in May 2019, require the Company to maintain, for each vessel, a minimum hull coverage ratio of 75% of the total outstanding principal balance during the first year of the lease period, 78% for the second year, 80% for the following two years and 90% of the total outstanding principal balance thereafter. As at September 30, 2020, these ratios were 91% (December 31, 2019 - 109%). Such requirements are assessed annually or quarterly with reference to vessel valuations compiled by one or more agreed upon third parties. As of the date these unaudited consolidated financial statements were issued, the Company was in compliance with all covenants in respect of its obligations related to finance leases. The weighted-average interest rate on the Company’s obligations related to finance leases as at September 30, 2020 was 7.6% (December 31, 2019 - 7.6%). As at September 30, 2020, the Company's total remaining commitments related to the financial liabilities of these vessels were approximately $559.7 million (December 31, 2019 - $601.7 million), including imputed interest of $163.6 million (December 31, 2019 - $186.9 million), repayable from 2020 through 2030, as indicated below: Commitments Year September 30, 2020 Remainder of 2020 14,235 2021 56,222 2022 56,213 2023 56,204 2024 56,348 Thereafter 320,481
Subsequent Event [Member]
Finance Leased Assets [Line Items]
Payments to Acquire Property, Plant, and Equipment | $	$ 56,700	$ 29,600
Suezmax, Aframax and LR2 Vessels [Member]
Finance Leased Assets [Line Items]
Number Of Vessels			16
Number of Vessels with Purchase Option			16
Aframax Tanker | Subsequent Event [Member]
Finance Leased Assets [Line Items]
Number Of Vessels						2
Suezmax Tankers
Finance Leased Assets [Line Items]
Number Of Vessels			3
Suezmax Tankers | Subsequent Event [Member]
Finance Leased Assets [Line Items]
Number Of Vessels					2
Minimum [Member]
Finance Leased Assets [Line Items]
Sale Leaseback Transaction, Lease Terms			9
Maximum
Finance Leased Assets [Line Items]
Sale Leaseback Transaction, Lease Terms			12
July 2017 Sale Leaseback [Member]
Finance Leased Assets [Line Items]
Debt Covenant Minimum Hull Coverage Ratio, Thereafter			100.00%
Debt Covenant Minimum Hull Coverage Ratio, Years 1, 2 and 3			90.00%
July 2017 Sale Leaseback [Member] | Minimum [Member]
Finance Leased Assets [Line Items]
Actual Hull Coverage Ratio			119.00%				110.00%
July 2017 Sale Leaseback [Member] | Maximum
Finance Leased Assets [Line Items]
Actual Hull Coverage Ratio			141.00%				132.00%
September 2018 Sale Leaseback [Member]
Finance Leased Assets [Line Items]
Debt Covenant Minimum Hull Coverage Ratio, Thereafter			90.00%
Debt Covenant Minimum Hull Coverage Ratio, Year 1			75.00%
Debt Covenant Minimum Hull Coverage Ratio, Year 2			78.00%
Maintain 80% Hull Coverage Ratio Year 3 & 4			80.00%
September 2018 Sale Leaseback [Member] | Minimum [Member]
Finance Leased Assets [Line Items]
Actual Hull Coverage Ratio			87.00%				106.00%
September 2018 Sale Leaseback [Member] | Maximum
Finance Leased Assets [Line Items]
Actual Hull Coverage Ratio			104.00%				123.00%
November 2018 Sale leaseback Transaction [Member]
Finance Leased Assets [Line Items]
Debt Covenant Minimum Hull Coverage Ratio			100.00%
November 2018 Sale leaseback Transaction [Member] | Minimum [Member] | Suezmax, Aframax and LR2 Sale Leaseback [Member]
Finance Leased Assets [Line Items]
Actual Hull Coverage Ratio			113.00%				140.00%
November 2018 Sale leaseback Transaction [Member] | Maximum | Suezmax, Aframax and LR2 Sale Leaseback [Member]
Finance Leased Assets [Line Items]
Actual Hull Coverage Ratio			156.00%				173.00%
May 2019 Sale Leaseback [Member]
Finance Leased Assets [Line Items]
Debt Covenant Minimum Hull Coverage Ratio, Thereafter			90.00%
Debt Covenant Minimum Hull Coverage Ratio, Year 1			75.00%
Actual Hull Coverage Ratio			91.00%				109.00%
Debt Covenant Minimum Hull Coverage Ratio, Year 2			78.00%
Maintain 80% Hull Coverage Ratio Year 3 & 4			80.00%
Finance Lease Obligations [Member]
Finance Leased Assets [Line Items]
Minimum liquidity covenant requirement | $			$ 35,000
Minimum liquidity as a percentage of consolidated debt covenant requirement			5.00%
Debt Covenant Minimum Free Liquidity And Undrawn Revolving Credit Line | $			$ 35,000
Finance Lease Obligations [Member] | Minimum [Member]
Finance Leased Assets [Line Items]
Long-term Debt, Term			6 months
Finance Lease Obligations [Member] | July 2017 Sale Leaseback [Member]
Finance Leased Assets [Line Items]
Number Of Vessels			4
Finance Lease Obligations [Member] | September 2018 Sale Leaseback [Member]
Finance Leased Assets [Line Items]
Number Of Vessels			6
Finance Lease Obligations [Member] | November 2018 Sale leaseback Transaction [Member]
Finance Leased Assets [Line Items]
Number Of Vessels			4
Finance Lease Obligations [Member] | May 2019 Sale Leaseback [Member]
Finance Leased Assets [Line Items]
Number Of Vessels			2

Leases - Future Minimum Lease P

Leases - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Finance Leased Assets [Line Items]
Finance Lease, Liability, Payment, Due	$ 559,700	$ 601,700
Finance Lease, Liability, Undiscounted Excess Amount	163,600	$ 186,900
Finance Lease, Liability, Payments, Due Next Twelve Months	14,235
Finance Lease, Liability, Payments, Due Year Two	56,222
Finance Lease, Liability, Payments, Due Year Three	56,213
Finance Lease, Liability, Payments, Due Year Four	56,204
Finance Lease, Liability, Payments, Due Year Five	56,348
Finance Lease, Liability, Payments, Due after Year Five	$ 320,481

Derivative Instruments - Summar

Derivative Instruments - Summary of Interest Rate Swap Positions (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2020USD ($)
Minimum [Member]
LIBOR-Based Debt:
Debt Instrument, Basis Spread on Variable Rate	2.25%
Maximum
LIBOR-Based Debt:
Debt Instrument, Basis Spread on Variable Rate	2.40%
London Interbank Offered Rate (LIBOR) [Member] | United States Dollar Denominated Interest Rate Swaps One [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 50,000
Derivative, Fair Value, Net	$ (989)
LIBOR-Based Debt:
Remaining Term	4 years 3 months 18 days
Fixed Swap Rate	0.76%

Derivative Instruments - Locati

Derivative Instruments - Location and Fair Value Amounts of Derivative Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Current portion of derivative assets	$ 0	$ 577
Derivative Assets (note 8)	0	82
Current portion of derivative liabilities (note 8)	755	86
Derivative liabilities (note 8)	717	0
Reported Value Measurement [Member]
Derivatives, Fair Value [Line Items]
Current portion of derivative assets	0	577
Derivative Assets (note 8)	0	82
Accounts receivable	0	(230)
Current portion of derivative liabilities (note 8)	755	86
Derivative liabilities (note 8)	717	0
Reported Value Measurement [Member] | Interest rate swap agreement
Derivatives, Fair Value [Line Items]
Current portion of derivative assets	0	577
Derivative Assets (note 8)	0	82
Accounts receivable	0	(230)
Current portion of derivative liabilities (note 8)	(272)	0
Derivative liabilities (note 8)	717	0
Reported Value Measurement [Member] | Forward freight agreements
Derivatives, Fair Value [Line Items]
Current portion of derivative assets	0	0
Derivative Assets (note 8)	0	0
Accounts receivable	0	0
Current portion of derivative liabilities (note 8)	(483)	(86)
Derivative liabilities (note 8)	$ 0	$ 0

Derivative Instruments - Gain (

Derivative Instruments - Gain (Loss) for Derivative Instruments Not Designated or Qualifying as Hedging Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Derivative [Line Items]
Realized gains (losses)	$ (242)	$ 1,048	$ 118	$ 2,788
Unrealized gains (losses)	(172)	405	(1,948)	(3,960)
Total	(414)	1,453	(1,830)	(1,172)
Interest rate swap agreement
Derivative [Line Items]
Realized gains (losses)	(58)	613	551	2,395
Unrealized gains (losses)	49	(541)	(1,648)	(5,010)
Total	(9)	72	(1,097)	(2,615)
Forward freight agreements
Derivative [Line Items]
Realized gains (losses)	(184)	435	(433)	393
Unrealized gains (losses)	(221)	946	(300)	1,050
Total	$ (405)	$ 1,381	$ (733)	$ 1,443

Other Income - Components of Ot

Other Income - Components of Other Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Other Liabilities Disclosure [Abstract]
Foreign exchange (loss) gain	$ (514)	$ 918	$ 534	$ 1,100
Other income	44	15	1,079	82
Total	$ (470)	$ 933	$ 1,613	$ 1,182

Freight Tax and Other Tax Exp_3

Freight Tax and Other Tax Expense (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	Aug. 31, 2020	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Jan. 01, 2019	Jan. 01, 2018
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits			$ 29,384	$ 36,240	$ 49,579	$ 32,059
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions				(2,114)
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations			(961)	0
Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions			2,290	2,067
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions			12,968
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities		$ 15,200	$ 8,556	$ 0
Settlement with Taxing Authority [Member]
Income Tax Contingency [Line Items]
Payments for Other Taxes	$ 7,700

Financial Instruments - Summary

Financial Instruments - Summary of Fair Value and Carrying Value of Assets and Liabilities Measured on Recurring and Non-recurring Basis (Details) $ in Thousands	Sep. 30, 2020USD ($)vessel	Dec. 31, 2019USD ($)	Sep. 30, 2019USD ($)	Dec. 31, 2018USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash, cash equivalents and restricted cash	$ 128,995	$ 96,790	$ 82,483	$ 60,507
Current portion of derivative liabilities (note 8)	755	86
Operating lease right-of-use assets (note 7)	6,148	19,560
At cost, less accumulated depreciation of $496.4 million (2019 - $537.1 million) (note 6)	1,131,742	1,223,085
Vessels related to finance leases, at cost, less accumulated depreciation of $126.9 million (2019 - $143.7 million) (note 7)	484,776	527,081
Short-term Debt	(20,000)	(50,000)
Long-term debt, including current portion (note 6)	(215,065)	(559,679)
Total obligations related to finance leases	(396,072)	(414,788)
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Current portion of derivative liabilities (note 8)	755	86
Reported Value Measurement [Member] | Interest rate swap agreement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Current portion of derivative liabilities (note 8)	(272)	0
Reported Value Measurement [Member] | Forward freight agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Current portion of derivative liabilities (note 8)	(483)	(86)
Fair Value, Recurring [Member] | Level 1 | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash, cash equivalents and restricted cash	128,995	95,332
Fair Value, Recurring [Member] | Level 1 | Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash, cash equivalents and restricted cash	128,995	95,332
Fair Value, Recurring [Member] | Level 2 | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term Debt	(19,994)	(50,000)
Long-term debt, including current portion (note 6)	(219,271)	(558,657)
Total obligations related to finance leases	(465,342)	(442,648)
Assets Held-for-sale, Long Lived, Fair Value Disclosure	0	37,240
Fair Value, Recurring [Member] | Level 2 | Estimate of Fair Value Measurement [Member] | Interest rate swap agreement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value	989
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value		(659)
Fair Value, Recurring [Member] | Level 2 | Estimate of Fair Value Measurement [Member] | Forward freight agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Current portion of derivative liabilities (note 8)	483	86
Fair Value, Recurring [Member] | Level 2 | Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term Debt	(20,000)	(50,000)
Advances to equity-accounted joint venture	5,280	9,930
Long-term debt, including current portion (note 6)	(222,375)	(559,679)
Total obligations related to finance leases	(396,072)	(414,788)
Assets Held-for-sale, Long Lived, Fair Value Disclosure	0	37,240
Fair Value, Recurring [Member] | Level 2 | Reported Value Measurement [Member] | Interest rate swap agreement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value	989
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value		(659)
Fair Value, Recurring [Member] | Level 2 | Reported Value Measurement [Member] | Forward freight agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Current portion of derivative liabilities (note 8)	483	$ 86
Fair Value, Nonrecurring [Member] | Level 2 | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Operating lease right-of-use assets (note 7)	6,148
At cost, less accumulated depreciation of $496.4 million (2019 - $537.1 million) (note 6)	46,750
Vessels related to finance leases, at cost, less accumulated depreciation of $126.9 million (2019 - $143.7 million) (note 7)	34,000
Fair Value, Nonrecurring [Member] | Level 2 | Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Operating lease right-of-use assets (note 7)	6,148
At cost, less accumulated depreciation of $496.4 million (2019 - $537.1 million) (note 6)	46,750
Vessels related to finance leases, at cost, less accumulated depreciation of $126.9 million (2019 - $143.7 million) (note 7)	$ 34,000
Property, Plant and Equipment [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Number Of Vessels | vessel	3
Aframax Tanker
Impaired Long-Lived Assets Held and Used [Line Items]
Number Of Vessels | vessel	5
Finance Lease Obligations [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Number Of Vessels | vessel	2

Capital Stock and Stock-Based_2

Capital Stock and Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	100,000,000		100,000,000		100,000,000
Preferred stock, par value (usd per share)	$ 0.01		$ 0.01		$ 0.01
Common stock, shares authorized (in shares)	585,000,000		585,000,000		585,000,000
Preferred stock, shares issued (in shares)	0		0		0
Restricted Stock [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period			78,300	53,800
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value			$ 1.3	$ 0.5
Class A
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	485,000,000		485,000,000		485,000,000
Common Stock, Par or Stated Value Per Share	$ 0.01		$ 0.01		$ 0.01
Common Stock, Voting Rights, Votes Per Share Owned			$ 1
Common stock, shares issued (in shares)	29,100,000		29,100,000		29,000,000
Class A | Restricted Stock Units
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues			44,800	34,100
Class B
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	100,000,000		100,000,000		100,000,000
Common Stock, Par or Stated Value Per Share	$ 0.01		$ 0.01		$ 0.01
Common Stock, Voting Rights, Votes Per Share Owned			$ 5
Maximum percentage of voting power			49.00%
Common stock, shares issued (in shares)	4,600,000		4,600,000		4,600,000
General and Administrative Expense [Member]
Class of Stock [Line Items]
Employee Benefits and Share-based Compensation	$ 0.4	$ 0.2	$ 1.3	$ 0.9

Related Party Transactions - Su

Related Party Transactions - Summary of Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Nov. 30, 2016
Related Party Transaction [Line Items]
Vessel operating expenses	$ (46,336)	$ (48,539)	$ (143,203)	$ (156,726)
Strategic and administrative service fees	(7,453)	(7,437)	(22,568)	(23,179)
Revenues	170,240	187,444	758,632	632,612
Vessel operating expenses - technical management fee
Related Party Transaction [Line Items]
Vessel operating expenses	(248)	0	(744)	0
Secondment fees
Related Party Transaction [Line Items]
Strategic and administrative service fees	(95)	(21)	(337)	(120)
LNG terminal services revenue
Related Party Transaction [Line Items]
Revenue from Related Parties	0	(150)	0	1,979
Technical management fee revenues
Related Party Transaction [Line Items]
Revenue from Related Parties	169	169	507	596
Service revenues
Related Party Transaction [Line Items]
Revenue from Related Parties	$ 3	$ 100	$ 12	$ 317
Teekay LNG Operating LLC [Member] | Bahrain LNG W.I.L.
Related Party Transaction [Line Items]
Ownership percentage					30.00%

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Due to Affiliate, Current			$ 2,932,000	$ 2,139,000
Payable to Manager [Member]
Related Party Transaction [Line Items]
Due to Affiliate, Current			$ 12,200,000	$ 7,900,000
Aframax Tanker | RSA Participants [Member] | Vessels Hire
Related Party Transaction [Line Items]
Amounts of transaction	$ 0	$ 2,000,000

Earnings (Loss) Per Share - Bas

Earnings (Loss) Per Share - Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss)	$ (44,434)	$ 98,198	$ 106,839	$ (19,850)	$ (14,307)	$ 12,447	$ 160,603	$ (21,710)
Weighted average number of common shares – basic (in shares)	33,738,143			33,623,608			33,712,124	33,610,936
Dilutive effect of stock-based awards (in shares)	0			0			230,067	0
Weighted average number of common shares – diluted (in shares)	33,738,143			33,623,608			33,942,191	33,610,936
(Loss) earnings per common share:
– Basic (usd per share)	$ (1.32)			$ (0.59)			$ 4.76	$ (0.65)
– Diluted (usd per share)	$ (1.32)			$ (0.59)			$ 4.73	$ (0.65)

Earnings (Loss) Per Share - Add

Earnings (Loss) Per Share - Additional Information (Details) - Class A - shares shares in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020
Share-based Payment Arrangement [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0.2	0.2
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0.2	0.1

Write-down of Assets (Details)

Write-down of Assets (Details) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020USD ($)vessel	Sep. 30, 2020USD ($)vessel
Impaired Long-Lived Assets Held and Used [Line Items]
Operating Lease, Impairment Loss | $	$ 1.4	$ 2.1
Aframax Tanker
Impaired Long-Lived Assets Held and Used [Line Items]
Number Of Vessels | vessel	5	5
Asset Impairment Charges | $	$ 43.5	$ 43.5
Number Of Vessels impaired | vessel	5	5

Sale of Assets (Details)

Sale of Assets (Details) $ in Millions	1 Months Ended		3 Months Ended	9 Months Ended
	Jul. 31, 2020USD ($)	May 31, 2020USD ($)	Sep. 30, 2020USD ($)vessel	Sep. 30, 2020USD ($)vessel	Dec. 31, 2019vessel
Property, Plant and Equipment [Line Items]
Operating Lease, Impairment Loss			$ 1.4	$ 2.1
Ship To Ship Transfer Business [Member] | Ship To Ship Transfer Business [Member]
Property, Plant and Equipment [Line Items]
Gain (Loss) on sale of ship-to-ship transfer business				3.1
Sale of ship-to-ship transfer business	$ 12.7	$ 14.3		27.1
Adjustment for final amounts of cash and other working capital on closing date				$ 1.1
Suezmax Tankers [Member]
Property, Plant and Equipment [Line Items]
Number Of Vessels | vessel			3	3
Number of Vessels Held for Sale | vessel					2
Gain (Loss) on Disposition of Assets				$ 2.6

Restructuring and Related Act_2

Restructuring and Related Activities (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Restructuring and Related Activities [Abstract]
Restructuring Charges	$ 1,398,000	$ 0	$ 1,398,000	$ 0
Restructuring Reserve	$ 1,400,000		$ 1,400,000		$ 0

Subsequent Events (Details)

Subsequent Events (Details) $ in Thousands	1 Months Ended		9 Months Ended
	Nov. 30, 2020USD ($)	Oct. 31, 2020USD ($)	Sep. 30, 2020USD ($)vessel	Sep. 30, 2019USD ($)	Nov. 13, 2020vessel	Oct. 22, 2020vessel
Subsequent Event [Line Items]
Payments to Acquire Property, Plant, and Equipment | $			$ 8,881	$ 7,210
Suezmax Tankers [Member]
Subsequent Event [Line Items]
Number Of Vessels			3
Subsequent Event [Member]
Subsequent Event [Line Items]
Payments to Acquire Property, Plant, and Equipment | $	$ 56,700	$ 29,600
Subsequent Event [Member] | Aframax Tanker
Subsequent Event [Line Items]
Number Of Vessels						2
Subsequent Event [Member] | Suezmax Tankers [Member]
Subsequent Event [Line Items]
Number Of Vessels					2