International Seaways (INSW) 10-Q 4 May 22 2022 Q1 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	3 Months Ended
	Mar. 31, 2022	May 02, 2022
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Mar. 31, 2022
Entity Registrant Name	INTERNATIONAL SEAWAYS, INC.
Entity Incorporation, State or Country Code	1T
Entity File Number	1-37836-1
Entity Tax Identification Number	98-0467117
Entity Address, Address Line One	600 Third Avenue
Entity Address, Address Line Two	39th Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10016
City Area Code	212
Local Phone Number	578-1600
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		49,660,837
Entity Central Index Key	0001679049
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2022
Amendment Flag	false
Common Stock [Member]
Title of 12(b) Security	Common Stock (no par value)
Trading Symbol	INSW
Security Exchange Name	NYSE
8.5% Senior Notes
Title of 12(b) Security	8.5% Senior Notes due 2023
Trading Symbol	INSW - PA
Security Exchange Name	NYSE

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current Assets:
Cash and cash equivalents	$ 74,553	$ 97,883
Voyage receivables, net of allowance for credit losses of $27 and $31 including unbilled receivables of $113,633 and $100,137	120,465	107,096
Other receivables	7,368	5,651
Inventories	2,335	2,110
Prepaid expenses and other current assets	16,558	11,759
Current portion of derivative asset	2,061	0
Vessel held for sale	23,148	0
Total Current Assets	246,488	224,499
Restricted cash	1,051	1,050
Vessels and other property, less accumulated depreciation of $266,771 and $249,336	1,773,264	1,802,850
Vessels construction in progress	60,034	49,291
Deferred drydock expenditures, net	60,473	55,753
Operating lease right-of-use assets	23,425	23,168
Investments in and advances to affiliated companies	183,361	180,331
Long-term derivative asset	5,959	1,296
Time charter contracts acquired, net	502	842
Other assets	12,036	7,700
Total Assets	2,366,593	2,346,780
Current Liabilities:
Accounts payable, accrued expenses and other current liabilities	56,116	44,964
Current portion of operating lease liabilities	10,767	8,393
Current installments of long-term debt	178,391	178,715
Current portion of derivative liability	0	2,539
Total Current Liabilities	245,274	234,611
Long-term operating lease liabilities	10,814	12,522
Long-term debt, net	943,032	926,270
Long-term derivative liability	0	757
Other liabilities	2,023	2,288
Total Liabilities	1,201,143	1,176,448
Commitments and contingencies
Equity:
Capital - 100,000,000 no par value shares authorized; 49,641,506 and 49,612,019 shares issued and outstanding	1,588,606	1,591,446
Accumulated deficit	(422,339)	(409,338)
Stockholders Equity Subtotal	1,166,267	1,182,108
Accumulated other comprehensive loss	(1,401)	(12,360)
Total equity before noncontrolling interests	1,164,866	1,169,748
Noncontrolling interests	584	584
Total Equity	1,165,450	1,170,332
Total Liabilities and Equity	$ 2,366,593	$ 2,346,780

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
CONDENSED CONSOLIDATED BALANCE SHEETS [Abstract]
Unbilled voyage receivable (in dollars)	$ 113,633	$ 100,137
Voyage receivables, allowance for credit losses	27	31
Vessels and other property, accumulated depreciation	$ 266,771	$ 249,336
Common stock, shares authorized	100,000,000	100,000,000
Common stock, no par value	$ 0	$ 0
Common stock, shares, issued	49,641,506	49,612,019
Common stock, shares, outstanding	49,641,506	49,612,019

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Shipping Revenues:
Shipping revenues	$ 101,482	$ 46,756
Operating Expenses:
Voyage expenses	3,507	1,587
Vessel expenses	60,317	26,327
Charter hire expenses	7,309	5,741
Depreciation and amortization	27,000	16,754
General and administrative	10,166	8,181
Third-party debt modification fees	(187)	0
Third-party debt modification fees	187	0
(Gain)/loss on disposal of vessels and other assets, net of impairments	(1,376)	11
Total operating expenses	107,110	58,601
Loss from vessel operations	(5,628)	(11,845)
Equity in income of affiliated companies	5,597	5,468
Operating loss	(31)	(6,377)
Other expense	(226)	292
Loss before interest expense and income taxes	(257)	(6,085)
Interest expense	(12,740)	(7,280)
Loss before income taxes	(12,997)	(13,365)
Income tax provision	(4)	0
Net loss	(13,001)	(13,365)
Net loss attributable to the Company	$ (13,001)	$ (13,365)
Weighted Average Number of Common Shares Outstanding:
Basic	49,571,337	28,023,815
Diluted	49,571,337	28,023,815
Per Share Amounts:
Basic net loss per share	$ (0.26)	$ (0.48)
Diluted net loss per share	$ (0.26)	$ (0.48)
Pool Revenue Leases [Member]
Shipping Revenues:
Shipping revenues	$ 83,762	$ 24,659
Time and Bareboat Charter Leases [Member]
Shipping Revenues:
Shipping revenues	6,175	14,698
Voyage Charter Leases [Member]
Shipping Revenues:
Shipping revenues	$ 11,545	$ 7,399

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Pool revenues, received from companies accounted for by the equity method	$ 23,271	$ 17,247

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME/(LOSS) [Abstract]
Net loss	$ (13,001)	$ (13,365)
Other comprehensive income/(loss), net of tax:
Net change in unrealized gains/(losses) on cash flow hedges	10,762	10,283
Defined benefit pension and other postretirement benefit plans:
Net change in unrecognized prior service costs	26	(8)
Net change in unrecognized actuarial losses	171	(56)
Other Comprehensive income, net of tax	10,959	10,219
Comprehensive loss attributable to the Company	$ (2,042)	$ (3,146)

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash Flows from Operating Activities:
Net loss	$ (13,001)	$ (13,365)
Items included in net loss not affecting cash flows:
Depreciation and amortization	27,000	16,754
Loss on write-down of vessels and other assets	1,697	0
Amortization of debt discount and other deferred financing costs	855	540
Amortization of time charter hire contracts acquired	340	0
Deferred financing costs write-off	133	0
Stock compensation	1,108	1,037
Earnings of affiliated companies	(5,597)	(5,468)
Other - net	580	425
Write-off of registration statement costs	0	694
Items included in net loss related to investing and financing activities:
(Gain)/loss on disposal of vessels and other assets, net	(3,073)	11
Cash distributions from affiliated companies	2,250	2,825
Payments for drydocking	(17,570)	(8,594)
Insurance claims proceeds related to vessel operations	954	528
Changes in operating assets and liabilities:
Increase in receivables	(13,369)	(2,740)
Decrease in deferred revenue	0	(2,995)
Net change in inventories, prepaid expenses and other current assets and accounts payable, accrued expense, and other current and long-term liabilities	(2,088)	(10,658)
Net cash used in operating activities	(19,781)	(21,006)
Cash Flows from Investing Activities:
Expenditures for vessels and vessel improvements	(37,989)	(3,281)
Proceeds from disposal of vessels and other property, net	24,257	(11)
Expenditures for other property	(390)	(179)
Investments in and advances to affiliated companies, net	(527)	54
Net cash used in investing activities	(14,649)	(3,417)
Cash Flows from Financing Activities:
Extinguishment of debt	(10,981)	0
Payments on debt	(35,284)	(15,371)
Proceeds from sale and leaseback financing, net of issuance and deferred financing costs	20,401	0
Payments on sale and leaseback financing	(9,085)	0
Borrowings on revolving credit facilities	50,000	0
Cash payments on derivatives containing other-than-insignificant financing element	0	(1,312)
Cash dividends paid	(2,980)	(1,681)
Cash paid to tax authority upon vesting of stock-based compensation	(970)	(489)
Net cash provided by/(used in) financing activities	11,101	(18,853)
Net decrease in cash, cash equivalents and restricted cash	(23,329)	(43,276)
Cash, cash equivalents and restricted cash at beginning of year	98,933	215,677
Cash, cash equivalents and restricted cash at end of period	$ 75,604	$ 172,401

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Thousands	Common Stock [Member]Restricted Stock	Common Stock [Member]Restricted Stock Units (RSUs) [Member]	Common Stock [Member]	Retained Earnings / (Accumulated deficit) [Member]Restricted Stock	Retained Earnings / (Accumulated deficit) [Member]Restricted Stock Units (RSUs) [Member]	Retained Earnings / (Accumulated deficit) [Member]	Accumulated Other Comprehensive Loss [Member]Restricted Stock	Accumulated Other Comprehensive Loss [Member]Restricted Stock Units (RSUs) [Member]	Accumulated Other Comprehensive Loss [Member]	Noncontrolling Interest [Member]Restricted Stock	Noncontrolling Interest [Member]Restricted Stock Units (RSUs) [Member]	Noncontrolling Interest [Member]	Restricted Stock	Restricted Stock Units (RSUs) [Member]	Total
Balance, beginning at Dec. 31, 2020			$ 1,280,501			$ (275,846)			$ (32,613)						$ 972,042
Net loss			0			(13,365)			0			$ 0			(13,365)
Other comprehensive income			0			0			10,219			0			10,219
Common stock cash dividends			(1,681)			0			0						(1,681)
Forfeitures of vested restricted stock awards			(489)			0			0			0			(489)
Compensation relating to restricted stock units awards	$ 202	$ 542		$ 0	$ 0		$ 0	$ 0		$ 0	$ 0		$ 202	$ 542
Compensation relating to stock option awards			293			0			0			0			293
Balance, ending at Mar. 31, 2021			1,279,368			(289,211)			(22,394)						967,763
Balance, beginning at Dec. 31, 2021			1,591,446			(409,338)			(12,360)			584			1,170,332
Net loss			0			(13,001)			0			0			(13,001)
Other comprehensive income			0			0			10,959			0			10,959
Common stock cash dividends			(2,978)			0			0			0			(2,978)
Forfeitures of vested restricted stock awards			(970)			0			0			0			(970)
Compensation relating to restricted stock units awards	$ 296	$ 501		$ 0	$ 0		$ 0	$ 0		$ 0	$ 0		$ 296	$ 501
Compensation relating to stock option awards			311			0			0			0			311
Balance, ending at Mar. 31, 2022			$ 1,588,606			$ (422,339)			$ (1,401)			$ 584			$ 1,165,450

BASIS OF PRESENTATION

BASIS OF PRESENTATION	3 Months Ended
	Mar. 31, 2022
BASIS OF PRESENTATION [Abstract]
BASIS OF PRESENTATION	Note 1 — Basis of Presentation: ​ The accompanying unaudited condensed consolidated financial statements include the accounts of International Seaways, Inc. (“INSW”), a Marshall Islands corporation, and its wholly owned subsidiaries. Unless the context indicates otherwise, references to “INSW”, the “Company”, “we”, “us” or “our”, refer to International Seaways, Inc. and its subsidiaries. As of March 31, 2022, the Company’s operating fleet consisted of 84 wholly-owned, finance leased or bareboat chartered-in and time-chartered-in oceangoing vessels, including two vessels in which the Company has interests through its joint ventures, engaged primarily in the transportation of crude oil and refined petroleum products in the International Flag trade through its wholly owned subsidiaries. In addition to its operating fleet, three dual-fuel LNG-powered VLCC newbuilds are scheduled for delivery to the Company in the first quarter of 2023, bringing the total operating and newbuild fleet to 87 vessels as of March 31, 2022. Subsequent to March 31, 2022, the Company sold and delivered two Panamaxes and a The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. They do not include all of the information and notes required by generally accepted accounting principles in the United States. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation of the results have been included. Operating results for the three months ended March 31, 2022 are not necessarily indicative of the results that may be expected for the year ending December 31, 2022. ​ The condensed consolidated balance sheet as of December 31, 2021 has been derived from the audited financial statements at that date but does not include all of the information and notes required by generally accepted accounting principles in the United States for complete financial statements. For further information, refer to the consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021. ​ All intercompany balances and transactions within INSW have been eliminated. Investments in 50% or less owned affiliated companies, in which INSW exercises significant influence, are accounted for by the equity method.

MERGER TRANSACTION

MERGER TRANSACTION	3 Months Ended
	Mar. 31, 2022
Merger Transaction [Abstract}
MERGER TRANSACTION	Note 2 — Merger Transaction: ​ Completion of Merger Transaction ​ On July 16, 2021 (the “Effective Time”), pursuant to an Agreement and Plan of Merger (the “Merger Agreement”) dated as of March 30, 2021, by and among INSW, Diamond S Shipping Inc., a Republic of the Marshall Islands corporation (“Diamond S”), and Dispatch Transaction Sub, Inc., a Republic of the Marshall Islands corporation and wholly-owned subsidiary of INSW (“Merger Sub”), Merger Sub merged with and into Diamond S (the “Merger”), with Diamond S surviving such merger as a wholly owned subsidiary of INSW. Immediately following the Effective Time, the Company contributed all of the outstanding stock of Diamond S to International Seaways Operating Corporation, a direct wholly-owned subsidiary of the Company. ​ At the Effective Time, each common share of Diamond S (the “Diamond S Common Shares”) issued and outstanding immediately prior to the Effective Time (excluding Diamond S Common Shares owned by Diamond S, the Company, Merger Sub or any of their respective direct or indirect wholly-owned subsidiaries) was cancelled in exchange for the right to receive 0.55375 of a share of common stock of the Company (the “INSW Common Stock”) and cash payable in respect of fractional shares. The aforementioned 0.55375 exchange ratio set forth in the Merger Agreement resulted in the issuance of 22,536,647 shares of INSW Common Stock, with the pre-Merger INSW shareholders and the former Diamond S shareholders owning approximately 55.75% and 44.25% , respectively, of the 50,674,393 issued and outstanding common stock of the Company immediately following the Effective Time. ​ As provided for under the terms of the Merger Agreement, on July 15, 2021, prior to the Effective Time, INSW paid a special dividend to its shareholders of record as of July 14, 2021 in an aggregate amount equal to $31.5 million ( $1.12 per share). ​

SIGNIFICANT ACCOUNTING POLICIES

SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2022
SIGNIFICANT ACCOUNTING POLICIES [Abstract]
SIGNIFICANT ACCOUNTING POLICIES	Note 3 — Significant Accounting Policies: ​ For a description of all of the Company’s material accounting policies, see Note 2, “Summary of Significant Accounting Policies,” to the Company’s consolidated financial statements as of and for the year ended December 31, 2021 included in the Company’s Annual Report on Form 10-K. The following is a summary of any changes or updates to the Company’s critical accounting policies for the current period: ​ Cash, cash equivalents and restricted cash — ​ Concentration of Credit Risk — ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ Allowance for Credit Losses - Balance at December 31, 2021 ​ $ 31 Reversal of expected credit losses ​ ​ (4) Balance at March 31, 2022 ​ $ 27 ​ We are also exposed to credit losses from off-balance sheet exposures related to guarantees of joint venture debt. See Note 7, “Equity Method Investments,” for more information on these off-balance sheet exposures. ​ During the three months ended March 31, 2022 and 2021, the Company did not have any individual customers who accounted for 10% or more of its revenues apart from the pools in which it participates. The pools in which the Company participates accounted in aggregate for 94% and 93% of consolidated voyage receivables at March 31, 2022 and December 31, 2021, respectively. ​ Deferred finance charges — ​ Vessels construction in progress — ​ Time Charter Contracts Acquired — ​ Recently Issued Accounting Standards Reference Rate Reform which provides relief for companies preparing for discontinuation of interest rates such as LIBOR. A contract modification is eligible to apply the optional relief to account for the modifications as a continuation of the existing contracts without additional analysis and consider embedded features to be clearly and closely related to the host contract without reassessment, if all of the following criteria are met: (1) contract references a rate that will be discontinued; (2) modified terms directly replace (or have potential to replace) this reference rate; and (3) changes to any other terms that change (or have potential to change) amount and timing of cash flows must be related to replacement of the reference rate. In addition, this guidance provides relief from certain hedge accounting requirements. Hedge accounting may continue uninterrupted when critical terms change due to reference rate reform. For cash flow hedges, entities can (1) disregard potential discontinuation of a referenced interest rate when assessing whether a hedged forecasted interest payment is probable; (2) continue hedge accounting upon a change in the hedged risk as long as the hedge is still highly effective; (3) assess effectiveness of the hedge relationship in ways that essentially disregards a potential mismatch in the variable rate indices between the hedging instrument and the hedged item; and (4) disregard the requirement that individual hedged transactions must share the same risk exposure for hedges of portfolios of forecasted transactions that reference a rate affected by reference rate reform. Relief provided by this ASU is optional and expires December 31, 2022. In January 2021, the FASB issued ASU 2021-01, Reference Rate Reform (ASC 848) to refine the scope of ASC 848 and to clarify some of its guidance. The Company has determined that its primary exposure to LIBOR is in relation to its floating rate debt facilities and the interest rate derivatives to which it is a party. On November 30, 2020, the benchmark administrator for the U.S. Dollar (“USD”) LIBOR announced a proposal to extend the publication of the most commonly used USD LIBOR settings until June 30, 2023. In light of this proposal, in an interagency statement, the Board of Governors of the Federal Reserve System, the Federal Deposit Insurance Corporation, and the Office of the Comptroller of the Currency issued guidance, strongly encouraging banks to cease entering into new contracts that use USD LIBOR as a reference rate as soon as practicable and in any event by December 31, 2021. Only in limited circumstances will it be appropriate for banks to enter into new contracts referencing USD LIBOR after December 31, 2021. The principal objective, and result, of these actions appears to be that legacy USD LIBOR-based instruments (i.e., those maturing after December 31, 2021) may continue to use USD LIBOR as a reference rate through June 30, 2023, without undermining the regulators’ determination that LIBOR should not be available for any other purpose. On January 25, 2021, the International Swaps and Derivatives Association, Inc. (“ISDA”), published new fallback provisions for derivatives linked to key interbank offered rates (“IBOR”) which will be incorporated into all new derivatives contracts that reference ISDA’s standard interest rate derivatives definitions. Such fallback provisions will also be included in legacy non-cleared derivatives if the counterparties have bilaterally agreed to include them or both have adhered to the IBOR fallback protocol. The Company has engaged and will continue to engage in discussions with its lending banks and the counterparties to its interest rate derivative contracts in advance of the June 30, 2023 sunset date for the USD LIBOR reference rate settings used in its agreements to evaluate the Company’s options. Based on information available today, the Company’s current view is that the Secured Overnight Financing Rate (“SOFR”) will be the alternative reference rate that the Company’s LIBOR-based agreements will transition to as the sunset date draws closer.

EARNINGS PER COMMON SHARE

EARNINGS PER COMMON SHARE	3 Months Ended
	Mar. 31, 2022
EARNINGS PER COMMON SHARE [Abstract]
EARNINGS PER COMMON SHARE	Note 4 — Earnings per Common Share: ​ Basic earnings per common share is computed by dividing earnings, after the deduction of dividends and undistributed earnings allocated to participating securities, by the weighted average number of common shares outstanding during the period. ​ The computation of diluted earnings per share assumes the issuance of common stock for all potentially dilutive stock options and restricted stock units not classified as participating securities. Participating securities are defined by ASC 260, Earnings Per Share ​ Weighted average shares of unvested restricted common stock considered to be participating securities totaled 87,117 and 51,087 for the three months ended March 31, 2022 and 2021, respectively. Such participating securities are allocated a portion of income, but not losses under the two-class method. As of March 31, 2022, there were 196,473 shares of restricted stock units and 811,906 stock options outstanding and considered to be potentially dilutive securities. ​ ​ Reconciliations of the numerator of the basic and diluted earnings per share computations are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Net (loss)/income attributable to the Company allocated to: ​ ​ ​ ​ ​ ​ Common Stockholders ​ $ (13,006) ​ $ (13,368) Participating securities ​ ​ 5 ​ ​ 3 ​ ​ $ (13,001) ​ $ (13,365) ​ For the three months ended March 31, 2022 and 2021 earnings per share calculations, there were no dilutive equity awards outstanding. Awards of 1,026,418 and 944,477 for the three months ended March 31, 2022 and 2021, respectively, were not included in the computation of diluted earnings per share because inclusion of these awards would be anti-dilutive.

BUSINESS AND SEGMENT REPORTING

BUSINESS AND SEGMENT REPORTING	3 Months Ended
	Mar. 31, 2022
BUSINESS AND SEGMENT REPORTING [Abstract]
BUSINESS AND SEGMENT REPORTING	Note 5 — Business and Segment Reporting: ​ The Company has two reportable segments: Crude Tankers and Product Carriers. The Company’s investments in and equity in income of the joint ventures with two floating storage and offloading service vessels are included in the Crude Tankers Segment. Adjusted income/(loss) from vessel operations for segment purposes is defined as income/(loss) from vessel operations before general and administrative expenses, third-party debt modification fees and loss/(gain) on disposal of vessels and other property, including impairments. The accounting policies followed by the reportable segments are the same as those followed in the preparation of the Company’s condensed consolidated financial statements. ​ Information about the Company’s reportable segments as of and for the three months ended March 31, 2022 and 2021 follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Crude ​ Product ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Tankers ​ Carriers ​ Other ​ Totals Three months ended March 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Shipping revenues ​ $ 39,610 ​ $ 61,872 ​ $ — ​ $ 101,482 Time charter equivalent revenues ​ ​ 36,475 ​ ​ 61,500 ​ ​ — ​ ​ 97,975 Depreciation and amortization ​ ​ 15,152 ​ ​ 11,841 ​ ​ 7 ​ ​ 27,000 Loss/(gain) on disposal of vessels and other assets, including impairments ​ ​ 1,843 ​ ​ (3,219) ​ ​ — ​ ​ (1,376) Adjusted income/(loss) from vessel operations ​ ​ (5,842) ​ ​ 9,198 ​ ​ (7) ​ ​ 3,349 Equity in income of affiliated companies ​ ​ 5,597 ​ ​ — ​ ​ — ​ ​ 5,597 Investments in and advances to affiliated companies at March 31, 2022 ​ ​ 160,298 ​ ​ 23,063 ​ ​ — ​ ​ 183,361 Adjusted total assets at March 31, 2022 ​ ​ 1,465,035 ​ ​ 803,077 ​ ​ — ​ ​ 2,268,112 Expenditures for vessels and vessel improvements ​ ​ 14,608 ​ ​ 23,381 ​ ​ — ​ ​ 37,989 Payments for drydocking ​ ​ 7,660 ​ ​ 9,910 ​ ​ — ​ ​ 17,570 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Shipping revenues ​ $ 37,510 ​ $ 9,246 ​ $ — ​ $ 46,756 Time charter equivalent revenues ​ ​ 35,950 ​ ​ 9,219 ​ ​ — ​ ​ 45,169 Depreciation and amortization ​ ​ 13,003 ​ ​ 3,728 ​ ​ 23 ​ ​ 16,754 Loss on disposal of vessels and other assets ​ ​ 11 ​ ​ — ​ ​ — ​ ​ 11 Adjusted loss from vessel operations ​ ​ (957) ​ ​ (2,673) ​ ​ (23) ​ ​ (3,653) Equity in income of affiliated companies ​ ​ 5,468 ​ ​ — ​ ​ — ​ ​ 5,468 Investments in and advances to affiliated companies at March 31, 2021 ​ ​ 137,361 ​ ​ 7,409 ​ ​ — ​ ​ 144,770 Adjusted total assets at March 31, 2021 ​ ​ 1,115,421 ​ ​ 255,220 ​ ​ — ​ ​ 1,370,641 Expenditures for vessels and vessel improvements ​ ​ 2,666 ​ ​ 615 ​ ​ — ​ ​ 3,281 Payments for drydocking ​ ​ 3,088 ​ ​ 5,506 ​ ​ — ​ ​ 8,594 ​ Reconciliations of time charter equivalent (“TCE”) revenues of the segments to shipping revenues as reported in the condensed statements of operations follow: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Time charter equivalent revenues ​ $ 97,975 ​ $ 45,169 Add: Voyage expenses ​ ​ 3,507 ​ ​ 1,587 Shipping revenues ​ $ 101,482 ​ $ 46,756 ​ Consistent with general practice in the shipping industry, the Company uses time charter equivalent revenues, which represent shipping revenues less voyage expenses, as a measure to compare revenue generated from a voyage charter to revenue generated from a time charter. Time charter equivalent revenues, a non-GAAP measure, provide additional meaningful information in conjunction with shipping revenues, the most directly comparable GAAP measure, because it assists Company management in making decisions regarding the deployment and use of its vessels and in evaluating their financial performance. ​ Reconciliations of adjusted income/(loss) from vessel operations of the segments to loss before income taxes, as reported in the condensed consolidated statements of operations follow: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Total adjusted income/(loss) from vessel operations of all segments ​ $ 3,349 ​ $ (3,653) General and administrative expenses ​ ​ (10,166) ​ ​ (8,181) Third-party debt modification fees ​ ​ (187) ​ ​ — Gain/(loss) on disposal of vessels and other assets, including impairments ​ ​ 1,376 ​ ​ (11) Consolidated loss from vessel operations ​ ​ (5,628) ​ ​ (11,845) Equity in income of affiliated companies ​ ​ 5,597 ​ ​ 5,468 Other (expense)/income ​ ​ (226) ​ ​ 292 Interest expense ​ ​ (12,740) ​ ​ (7,280) Loss before income taxes ​ $ (12,997) ​ $ (13,365) ​ Reconciliations of total assets of the segments to amounts included in the condensed consolidated balance sheets follow: ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ March 31, 2022 ​ March 31, 2021 Adjusted total assets of all segments ​ $ 2,268,112 ​ $ 1,370,641 Corporate unrestricted cash and cash equivalents ​ ​ 74,553 ​ ​ 156,178 Restricted cash ​ ​ 1,051 ​ ​ 16,223 Other unallocated amounts ​ ​ 22,877 ​ ​ 9,010 Consolidated total assets ​ $ 2,366,593 ​ $ 1,552,052 ​

VESSELS

VESSELS	3 Months Ended
	Mar. 31, 2022
VESSELS, DEFERRED DRYDOCK AND OTHER PROPERTY [Abstract]
VESSELS, DEFERRED DRYDOCK AND OTHER PROPERTY	Note 6 — Vessels: ​ Impairment of Vessels and Other Property ​ The Company gave consideration as to whether events or changes in circumstances had occurred since December 31, 2021, that could indicate that the carrying amounts of the vessels in the Company’s fleet may not be recoverable. During the quarter ended March 31, 2022, the Company concluded that the contracted sales of one 2004-built Panamax and one 2006-built Handysize product carrier resulted in the recognition of held for sale impairments charges aggregating $1.2 million. ​ In addition, the Company concluded that the subsequent execution of a memorandum of agreement in April 2022 for the sale of a 2006-built Handysize product carrier constituted an impairment triggering event. In developing estimates of undiscounted future cash flows for performing Step 1 of the impairment test as of March 31, 2022, March 31, 2022 ​ The Company also recognized an aggregate loss of approximately $0.7 million during the quarter ended March 31, 2022, related to the cost to terminate the purchase and installation contracts for ballast water treatment systems on three of the Company’s MRs that were sold during 2021. ​ Vessel Acquisitions and Construction Commitments ​ In January 2022, the Company entered into memoranda of agreements for the sale of a 2010-built MR for a sale price of $16.5 million and the purchase of a 2011-built LR1 for a purchase price of $19.5 million with the same counterparty. The LR1 was delivered into our niche commercial pool, Panamax International. The Company closed both transactions during the first quarter of 2022, with a net cash outflow of $3.0 million representing the difference in value between the two vessels. The LR1 vessel replaced the MR as collateral under the $525 Million Credit Facility with no further mandatory principal repayment required. ​ On March 11, 2021, the Company entered into agreements to construct three dual-fuel LNG-powered VLCCs at Daewoo Shipbuilding and Marine Engineering’s shipyard. The VLCCs will be able to burn LNG in their power plant, which will significantly reduce greenhouse gas emissions. Upon delivery to the Company in the first quarter of 2023, the vessels will be employed on seven-year time charter contracts with an oil major – Shell. The total construction cost for the vessels is approximately $290.0 million, which will be paid for through a combination of cash on hand and funds drawn from the BoComm Lease Financing (See Note 10, “Debt”). essels construction in progress as of March 31, 2022 and December 31, 2021, respectively. The remaining commitments on the contracts for the construction of these vessels as of March 31, 2022 was $230.6 million, of which the BoComm Lease Financing is expected to provide additional funding of $230.4 million over the course of the construction and delivery of the three vessels. ​ Disposal/Sales of Vessels ​ As discussed above, during the quarter ended March 31, 2022, the Company delivered a 2010-built MR to buyers and recognized an aggregate gain of $4.6 million. Also, during the quarter ended March 31, 2022, the Company entered into memoranda of agreements for the sales of one 2002-built Panamax, one 2004-built Panamax and one 2006-built Handysize product carrier, which were delivered to the buyers in April 2022. Costs to sell (mainly bunker consumption costs) totaling $0.8 million were recognized during the quarter for t hese three vessels, ​ In addition, in April 2022, the Company entered into memoranda of agreements for the sale of its three remaining 2006-built Handysize product carriers and one 2008-built MR, which are expected to be delivered to their buyers during the second quarter of 2022. ​ ​

EQUITY METHOD INVESTMENTS

EQUITY METHOD INVESTMENTS	3 Months Ended
	Mar. 31, 2022
EQUITY METHOD INVESTMENTS [Abstract]
EQUITY METHOD INVESTMENTS	Note 7 — Equity Method Investments: ​ Investments in affiliated companies include joint ventures accounted for using the equity method. As of March 31, 2022, the Company had a 50% interest in two joint ventures - TI Africa Limited (“TI Africa”) and TI Asia Limited (“TI Asia”), which operate two Floating Storage and Offloading Service vessels that were converted from two ULCCs (collectively the “FSO Joint Venture”). ​ The FSO Joint Venture is a party to a number of contracts: (a) the FSO Joint Venture is an obligor pursuant to a guarantee facility agreement dated as of July 14, 2017, by and among, the FSO Joint Venture, ING Belgium NV/SA, as issuing bank, and Euronav and INSW, as guarantors (the “Guarantee Facility”); (b) the FSO Joint Venture is party to two service contracts with NOC (the “NOC Service Contracts”) and (c) the FSO Joint Venture is a borrower under a $220 million secured credit facility by and among TI Africa and TI Asia, as joint and several borrowers, ABN AMRO Bank N.V. and ING Belgium SA/NV, as Lenders, Mandated Lead Arrangers and Swap Banks, and ING Bank N.V., as Agent and as Security Trustee. INSW severally guarantees the obligations of the FSO Joint Venture pursuant to the Guarantee Facility. ​ The FSO Joint Venture drew down on a $220 million credit facility in April 2018. The Company provided a guarantee for the $110 million FSO Term Loan portion of the facility, which has an interest rate of LIBOR plus two percent and ​ Investments in and advances to affiliated companies as reflected in the accompanying condensed consolidated balance sheet as of March 31, 2022 consisted of: FSO Joint Venture of $145.1 million and Other of $38.3 million, which primarily relates to working capital deposits that the Company maintains with commercial pools in which it participates. ​ A condensed summary of the results of operations of the joint ventures follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Shipping revenues ​ $ 25,887 ​ $ 25,846 Ship operating expenses ​ ​ (14,292) ​ ​ (13,931) Income from vessel operations ​ ​ 11,595 ​ ​ 11,915 Interest expense ​ ​ (543) ​ ​ (1,212) Income tax provision ​ ​ (1,029) ​ ​ (993) Net income ​ $ 10,023 ​ $ 9,710 ​

VARIABLE INTEREST ENTITIES (VIE

VARIABLE INTEREST ENTITIES (VIEs)	3 Months Ended
	Mar. 31, 2022
VARIABLE INTEREST ENTITIES (VIEs) [Abstract]
VARIABLE INTEREST ENTITIES (VIEs)	Note 8 — Variable Interest Entities (“VIEs”): ​ Consolidated VIEs ​ Diamond Anglo Ship Management Pte. Ltd. — Diamond Anglo Ship Management Pte. Ltd. (“DASM”) was formed in January 2018 by Diamond S and Anglo Eastern Investment Holdings Ltd. (“AE Holdings”), a third-party, to provide ship management services to some of Diamond S’ vessels. DASM is owned 51% by the Company and 49% by AE Holdings. AE Holdings does not participate in the income or equity of DASM. as the Company has the ability to direct the activities that most significantly impact the DASM’s economic performance ​ Unconsolidated VIEs ​ As of March 31, 2022, all of the six commercial pools in which the Company participates and the two FSO joint ventures were determined to be VIEs for which the Company is not considered a primary beneficiary. ​ ​ The following table presents the carrying amounts of assets and liabilities in the condensed consolidated balance sheet related to the unconsolidated VIEs as of March 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ ​ ​ Condensed Investments in Affiliated Companies ​ ​ ​ ​ $ 181,960 ​ In accordance with accounting guidance, the Company evaluated its maximum exposure to loss related to these unconsolidated VIEs by assuming a complete loss of the Company’s investment in these VIEs. The table below compares the Company’s liability in the condensed consolidated balance sheet to the maximum exposure to loss at March 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ Condensed ​ Maximum Exposure to Other Liabilities ​ $ – ​ $ 195,271 ​ In addition, as of March 31, 2022, the Company had approximately $106.9 million of trade receivables from the pools that were determined to be a VIE. These trade receivables, which are included in voyage receivables in the accompanying condensed consolidated balance sheet, have been excluded from the above tables and the calculation of INSW’s maximum exposure to loss. The Company does not record the maximum exposure to loss as a liability because it does not believe that such a loss is probable of occurring as of March 31, 2022.

FAIR VALUE OF FINANCIAL INSTRUM

FAIR VALUE OF FINANCIAL INSTRUMENTS, DERIVATIVES AND FAIR VALUE DISCLOSURES	3 Months Ended
	Mar. 31, 2022
FAIR VALUE OF FINANCIAL INSTRUMENTS, DERIVATIVES AND FAIR VALUE DISCLOSURES [Abstract]
FAIR VALUE OF FINANCIAL INSTRUMENTS, DERIVATIVES AND FAIR VALUE DISCLOSURES	Note 9 — Fair Value of Financial Instruments, Derivatives and Fair Value Disclosures: ​ The estimated fair values of the Company’s financial instruments, other than derivatives that are not measured at fair value on a recurring basis, categorized based upon the fair value hierarchy, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ March 31, 2022 ​ December 31, 2021 ​ Fair Value Level Cash and cash equivalents (1) ​ $ 75,604 ​ $ 98,933 ​ ​ Level 1 $390 Million Facility Term Loan ​ ​ (172,766) ​ ​ (191,050) ​ ​ Level 2 $525 Million Facility Term Loan ​ ​ (198,265) ​ ​ (216,289) ​ ​ Level 2 $525 Million Facility Revolving Loan ​ ​ (94,193) ​ ​ (44,193) ​ ​ Level 2 $360 Million Facility Term Loan ​ ​ (96,413) ​ ​ (105,325) ​ ​ Level 2 $360 Million Facility Revolving Loan ​ ​ (38,889) ​ ​ (38,889) ​ ​ Level 2 Macquarie Credit Facility ​ ​ (18,950) ​ ​ (19,475) ​ ​ Level 2 ING Credit Facility ​ ​ (24,479) ​ ​ (25,000) ​ ​ Level 2 Ocean Yield Lease Financing ​ ​ (363,105) ​ ​ (370,305) ​ ​ Level 2 BoComm Lease Financing ​ ​ (14,411) ​ ​ (9,608) ​ ​ Level 2 Toshin Lease Financing ​ ​ (16,677) ​ ​ (16,995) ​ ​ Level 2 Hyuga Lease Financing ​ ​ (16,386) ​ ​ n/a ​ ​ Level 2 COSCO Lease Financing ​ ​ (51,493) ​ ​ (52,746) ​ ​ Level 2 8.5% Senior Notes ​ ​ (25,833) ​ ​ (25,940) ​ ​ Level 1 (1) Includes restricted cash of $1.1 million at March 31, 2022 and December 31, 2021, respectively. ​ ​ Derivatives ​ Derivatives are recorded on a net basis by counterparty when a legal right of offset exists. The Company had the following amounts recorded on a gross basis by transaction in the accompanying unaudited condensed consolidated balance sheets related to the Company’s use of derivatives as of March 31, 2022 and December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Current portion of derivative asset ​ Long-term derivative ​ Current portion of derivative liabilities ​ Long-term derivative March 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivatives designated as hedging instruments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swaps ​ $ 2,061 ​ $ 5,959 ​ $ — ​ $ — Total ​ $ 2,061 ​ $ 5,959 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivatives designated as hedging instruments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swaps ​ $ — ​ $ 1,296 ​ $ (2,539) ​ $ (757) Total ​ $ — ​ $ 1,296 ​ $ (2,539) ​ $ (757) ​ The following tables present information with respect to gains and losses on derivative positions reflected in the condensed consolidated statements of operations or in the condensed consolidated statements of comprehensive income. ​ The effect of cash flow hedging relationships recognized in other comprehensive income excluding amounts reclassified from accumulated other comprehensive loss, including hedges of equity method investees, for the three months ended March 31, 2022 and 2021 follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Derivatives designated as hedging instruments: ​ ​ ​ ​ ​ ​ Interest rate swaps ​ $ 9,058 ​ $ 7,747 ​ ​ ​ ​ ​ ​ ​ Other-than-insignificant financing element of derivatives: ​ ​ ​ ​ ​ ​ Interest rate swaps ​ ​ — ​ ​ (466) Total other comprehensive income ​ $ 9,058 ​ $ 7,281 ​ The effect of cash flow hedging relationships on the condensed consolidated statement of operations is presented excluding hedges of equity method investees. The effect of the Company’s cash flow hedging relationships on the condensed consolidated statement of operations for the three months ended March 31, 2022 and 2021 follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Derivatives designated as hedging instruments: ​ ​ ​ ​ ​ ​ Interest rate swaps ​ $ 992 ​ $ 1,115 ​ ​ ​ ​ ​ ​ ​ Discontinued hedging instruments: ​ ​ ​ ​ ​ ​ Interest rate swap ​ ​ 582 ​ ​ — ​ ​ ​ ​ ​ ​ ​ Other-than-insignificant financing element of derivatives: ​ ​ ​ ​ ​ ​ Interest rate swaps ​ ​ — ​ ​ 1,593 Total interest expense ​ $ 1,574 ​ $ 2,708 ​ See Note 13, “Accumulated Other Comprehensive Loss,” for disclosures relating to the impact of derivative instruments on accumulated other comprehensive loss. ​ The following table presents the fair values, which are pre-tax, for assets and liabilities measured on a recurring basis (excluding investments in affiliated companies): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ March 31, 2022 ​ December 31, 2021 ​ Fair Value Level Derivative Assets (interest rate swaps) ​ $ 8,020 ​ $ 1,296 ​ ​ Level 2 (1) Derivative Liabilities (interest rate swaps) ​ ​ — ​ ​ (3,296) ​ ​ Level 2 (1) (1) For the interest rate swaps, fair values are derived using valuation models that utilize the income valuation approach. These valuation models take into account contract terms such as maturity, as well as other inputs such as interest rate yield curves and creditworthiness of the counterparty and the Company. ​ The following table summarizes the fair values of assets for which impairment charges were recognized for the three months ended March 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ Fair Value ​ ​ Level 2 ​ ​ Total Impairment Crude Tankers - Vessels held for sale (1)(2) ​ $ 7,561 ​ $ 7,561 ​ $ (1,019) Product Carriers - Vessels held for sale (1) (2) ​ ​ 9,850 ​ ​ 9,850 ​ ​ (207) Product Carriers - Vessels held for use (1) (2) ​ ​ 9,575 ​ ​ 9,575 ​ ​ (471) (1) A pre-tax held for sale impairment charge of $1.0 million related to one Panamax in the Crude Tankers segment was recorded during the three months ended March 31, 2022, including a charge of $0.9 million to write the value of the vessel down to its estimated fair value, and estimated costs to sell the vessel of $0.1 million. A pre-tax held for sale impairment charge of $0.2 million related to one MR in the Product Carriers segment was recorded during the three months ended March 31, 2022, consisting of $0.2 million costs to sell the vessel. A pre-tax held for use impairment charge of $0.5 million related to one Handysize product carrier was recorded during the three months ended March 31, 2022 to write the value of the vessel down to its estimated fair value. (2) Fair value measurement of $27.0 million at March 31, 2022 used to determine the impairments for the vessels was based upon a market approach, which considered the expected sale prices of the vessels based on the executed memoranda of agreements as discussed in Note 6, "Vessels." The expected sales prices are considered to be Level 2 because sales of vessels occur somewhat infrequently .

DEBT

DEBT	3 Months Ended
	Mar. 31, 2022
DEBT [Abstract]
DEBT	Note 10 — Debt: ​ Debt consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ March 31, 2022 December 31, 2021 $390 Million Facility Term Loan, due 2025, net of unamortized deferred finance costs of $1,997 and $2,357 ​ $ 170,769 ​ $ 188,693 $525 Million Facility Term Loan, due 2024 ​ ​ 198,265 ​ ​ 216,289 $525 Million Facility Revolving Loan, due 2024 ​ ​ 94,193 ​ ​ 44,193 $360 Million Facility Term Loan, due 2024 ​ ​ 96,413 ​ ​ 105,325 $360 Million Facility Revolving Loan, due 2024 ​ ​ 38,889 ​ ​ 38,889 Macquarie Credit Facility, due 2025, net of unamortized deferred finance costs of $706 and $755 ​ ​ 18,244 ​ ​ 18,720 ING Credit Facility, due 2026, net of unamortized deferred finance costs of $513 and $546 ​ ​ 23,966 ​ ​ 24,454 Ocean Yield Lease Financing, due 2031, net of unamortized deferred finance costs of $3,632 and $3,799 ​ ​ 359,474 ​ ​ 366,506 BoComm Lease Financing, due 2030, net of unamortized deferred finance costs of $150 and $114 ​ ​ 14,261 ​ ​ 9,494 Toshin Lease Financing, due 2031, net of unamortized deferred finance costs of $417 and $428 ​ ​ 16,260 ​ ​ 16,567 COSCO Lease Financing, due 2028, net of unamortized deferred finance costs of $1,375 and $1,353 ​ ​ 50,118 ​ ​ 51,393 Hyuga Lease Financing, due 2031, net of unamortized deferred finance costs of $361 ​ ​ 16,025 ​ ​ — 8.5% Senior Notes, due 2023, net of unamortized deferred finance costs of $454 and $538 ​ ​ 24,546 ​ ​ 24,462 ​ ​ ​ 1,121,423 ​ ​ 1,104,985 Less current portion ​ ​ (178,391) ​ ​ (178,715) Long-term portion ​ $ 943,032 ​ $ 926,270 ​ Capitalized terms used hereafter have the meaning given in these condensed consolidated financial statements or in the respective transaction documents referred to below, including subsequent amendments thereto. ​ On March 4, 2022, the Company borrowed $50.0 million under the $ Million Facility Revolving Loan. As of March 31, 2022, the available amounts under the $ Million Facility Revolving Loan and the $ Million Facility Revolving Loan were $40.0 million, $ million and . ​ Hyuga Lease Financing ​ On January 14, 2022, the Company entered into a lease financing arrangement with Hyuga Kaiun Co., Ltd (“Hyuga”) for the sale and leaseback of a 2011-built MR, which was a $390 Million Facility Collateral Vessel, for a net sale price of $16.7 million (the “Hyuga Lease Financing”). The transaction generated net proceeds of $5.7 million, after prepaying $11.0 million of the $390 Million Facility Term Loan. Under the lease financing arrangement, the vessel is subject to a nine-year bareboat charter at a bareboat rate of $6,300 per day for the first three years, $6,200 per day for the second three years, and $6,000 per day for the last three years, with purchase options exercisable commencing at the end of the fourth year and a $1.5 million purchase obligation at the end of the nine-year term. ​ Kaiyo Lease Financing ​ On April 25, 2022, the Company entered into a lease financing arrangement with Kaiyo Ltd. (“Kaiyo”) for the sale and leaseback of a 2010-built MR, which was a $390 Million Facility Collateral Vessel, for a net sale price of $15.2 million (the “Kaiyo Lease Financing”). The transaction generated net proceeds of $5.4 million, after prepaying $9.8 million of the $390 Million Facility Term Loan. Under the lease financing arrangement, the vessel is subject to an eight-year bareboat charter at a bareboat rate of $6,250 per day for the first four years, and $6,150 per day for the remaining four years, with purchase options exercisable commencing at the end of the fourth year and a $1.5 million purchase obligation at the end of the eight-year term. ​ The closing of the Kaiyo Lease Financing reduced the number of vessels collateralizing the $ to nine subsequent to March 31, 2022 and also resulted in a reduction in the scheduled future quarterly principal amortization from $7.3 million to $6.9 million. ​ Debt Covenants ​ The Company was in compliance with the financial and non-financial covenants under all of its financing arrangements as of March 31, 2022. ​ The $390 Million Credit Facility, the Amended and Restated $525 Million Credit Agreement, the Amended and Restated $360 Million Credit Agreement, the Macquarie Credit Facility, the ING Credit Facility and certain of the Company’s lease financing arrangements contain customary representations, warranties, restrictions and covenants applicable to the Company, the Borrower and the subsidiary guarantors (and in certain cases, other subsidiaries), including financial covenants that require the Company (i) to maintain a minimum liquidity level of the greater of $50 million and 5% of the Company’s Consolidated Indebtedness; (ii) to ensure the Company’s and its consolidated subsidiaries’ Maximum Leverage Ratio will not exceed 0.60 to 1.00 at any time; (iii) to ensure that Current Assets exceeds Current Liabilities (which is defined to exclude the current potion of Consolidated Indebtedness); and (iv) to ensure the aggregate Fair Market Value of the Collateral Vessels will not be less than 135% of the aggregate outstanding principal amount of the Term Loans and Revolving Loans of each Facility. The 8.5% Senior Notes Indenture contains certain restrictive covenants, including covenants that, subject to certain exceptions and qualifications, restrict our ability to make certain payments if a default under the Indenture has occurred and is continuing or will result therefrom and require us to limit the amount of debt we incur, maintain a certain minimum net worth and provide certain reports. The Indenture also provides for certain customary events of default (subject, in certain cases, to receipt of notice of default and/or customary grace or cure periods). Pursuant to the limitation on borrowings covenant, the Company shall not permit Total Borrowings (as defined in the Indenture) to equal or exceed 70% of Total Assets (as defined in the Indenture). The Company shall also ensure that Net Worth (defined as Total Assets, less Intangible assets and Total Borrowings, as defined in the Indenture) exceeds $600 million pursuant to the Minimum Net Worth covenant. ​ The Company’s credit facilities also require it to comply with a number of covenants, including the delivery of quarterly and annual financial statements, budgets and annual projections; maintaining required insurances; compliance with laws (including environmental); compliance with the Employee Retirement Income Security Act of 1974 (“ERISA”); maintenance of flag and class of the collateral vessels; restrictions on consolidations, mergers or sales of assets; limitations on liens; limitations on issuance of certain equity interests; limitations on transactions with affiliates; and other customary covenants and related provisions. ​ Interest Expense ​ Total interest expense before the impact of capitalized interest, including amortization of issuance and deferred financing costs (for additional information related to deferred financing costs see Note 3, “Significant Accounting Policies”), commitment, administrative and other fees for all of the Company’s debt facilities for the three months ended March 31, 2022 and 2021 was $13.3 million and $7.2 million, respectively. Interest paid for the Company’s debt facilities for the three months ended March 31, 2022 and 2021 was $11.8 million and $6.3 million respectively. ​ Debt Modifications, Repurchases and Extinguishments ​ During the first quarter of 2022, the Company recognized a net loss of $0.1 million, which is included in other expense in the accompanying condensed consolidated statement of operations. The net loss reflects a write-off of $0.1 million of unamortized deferred financing costs associated with the $11.0 million principal prepayment of the $390 Million Facility Term Loan in January 2022 (in connection with the Hyuga Lease Financing transaction described above), which was treated as a partial extinguishment.

TAXES

TAXES	3 Months Ended
	Mar. 31, 2022
TAXES [Abstract]
TAXES	Note 11 — Taxes: ​ The Company derives substantially all of its gross income from the use and operation of vessels in international commerce. The Company’s entities that own and operate vessels are primarily domiciled in the Marshall Islands and Liberia, which do not impose income tax on shipping operations. The Company also has or had subsidiaries in various jurisdictions that perform administrative, commercial or technical management functions. These subsidiaries are subject to income tax based on the services performed in countries in which their offices are located; current and deferred income taxes are recorded accordingly. ​ A substantial portion of income earned by the Company is not subject to income tax. With respect to subsidiaries not subject to income tax in their respective countries of incorporation, no deferred taxes are provided for the temporary differences in the bases of the underlying assets and liabilities for tax and accounting purposes. ​ As of March 31, 2022, the Company believes it will qualify for an exemption from U.S. federal income taxes under Section 883 of the U.S. Internal Revenue Code of 1986, as amended (the “Code”) and U.S. Treasury Department regulations for the 2022 calendar year, so long as less than 50 percent of the total value of the Company’s stock is held by one or more shareholders who own 5% or more of the Company’s stock for more than half of the days of 2022. ​ 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 additional legal advice as to the 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. ​ The Marshall Islands and Liberia impose tonnage taxes, which are assessed on the tonnage of certain of the Company’s vessels. These tonnage taxes are included in vessel expenses in the accompanying condensed consolidated statements of operations.

CAPITAL STOCK AND STOCK COMPENS

CAPITAL STOCK AND STOCK COMPENSATION	3 Months Ended
	Mar. 31, 2022
CAPITAL STOCK AND STOCK COMPENSATION [Abstract]
CAPITAL STOCK AND STOCK COMPENSATION	Note 12 — Capital Stock and Stock Compensation: ​ The Company accounts for stock-based compensation expense in accordance with the fair value method required by ASC 718, Compensation – Stock Compensation ​ Restricted Stock Units and Stock Options ​ In April 2022, the Company granted 328,554 time-based restricted stock units (“RSUs”) to certain of its senior officers and employees. The weighted average grant date fair value of these awards was $19.63 per RSU. Each RSU represents a contingent right to receive one share of INSW common stock upon vesting. 304,650 of the RSUs awarded will vest in equal installments on each of the first three anniversaries of the grant date and 23,904 of the RSUs awarded will cliff vest on September 30, 2023. ​ In April 2022, the Company also awarded 124,590 performance-based RSUs to certain of its senior officers and employees. Each performance stock unit represents a contingent right to receive RSUs based upon the covered employees being continuously employed through the end of the period over which the performance goals are measured and shall vest as follows: (i) one ​ ​ Dividends ​ On February 28, 2022, the Company’s Board of Directors declared a regular quarterly cash dividend of $0.06 per share. Pursuant to such declaration, the Company made dividend payments totaling $3.0 million on March 28, 2022 to stockholders of record as of March 14, 2022. ​ Share Repurchases ​ In connection with the settlement of vested restricted stock units, the Company repurchased 57,726 and 22,830 shares of common stock during the three months ended March 31, 2022 and 2021, respectively, at an average cost of $16.81 and $21.42, respectively, per share (based on the market prices on the dates of vesting) from employees and certain members of management to cover withholding taxes. ​ As of March 31, 2022, the remaining buyback authorization under the Company’s was $33.3 million. ​ ​

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE LOSS	3 Months Ended
	Mar. 31, 2022
ACCUMULATED OTHER COMPREHENSIVE LOSS [Abstract]
ACCUMULATED OTHER COMPREHENSIVE LOSS	Note 13 — Accumulated Other Comprehensive Loss: ​ The components of accumulated other comprehensive loss, net of related taxes, in the condensed consolidated balance sheets follow: ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ March 31, 2022 December 31, 2021 Unrealized gains/(losses) on derivative instruments ​ $ 5,899 ​ $ (4,863) Items not yet recognized as a component of net periodic benefit cost (pension plans) ​ ​ (7,300) ​ ​ (7,497) ​ ​ $ (1,401) ​ $ (12,360) ​ The changes in the balances of each component of accumulated other comprehensive loss, net of related taxes, during the three months ended March 31, 2022 and 2021 follow: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Unrealized gains/(losses) on cash flow hedges ​ Items not yet recognized as a component of net periodic benefit cost ​ Total Balance as of December 31, 2021 ​ $ (4,863) ​ $ (7,497) ​ $ (12,360) Current period change, excluding amounts reclassified ​ ​ ​ ​ ​ ​ ​ ​ ​ from accumulated other comprehensive loss ​ ​ 9,058 ​ ​ 197 ​ ​ 9,255 Amounts reclassified from accumulated other comprehensive loss ​ ​ 1,704 ​ ​ — ​ ​ 1,704 Balance as of March 31, 2022 ​ $ 5,899 ​ $ (7,300) ​ $ (1,401) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, 2020 ​ $ (24,098) ​ ​ (8,515) ​ ​ (32,613) Current period change, excluding amounts reclassified ​ ​ ​ ​ ​ ​ ​ ​ ​ from accumulated other comprehensive loss ​ ​ 7,281 ​ ​ (64) ​ ​ 7,217 Amounts reclassified from accumulated other comprehensive loss ​ ​ 3,002 ​ ​ — ​ ​ 3,002 Balance as of March 31, 2021 ​ $ (13,815) ​ $ (8,579) ​ $ (22,394) ​ ​ Amounts reclassified out of each component of accumulated other comprehensive loss follow: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 ​ Statement of Operations Reclassifications of losses on cash flow hedges: ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swaps entered into by the Company's ​ ​ ​ ​ ​ ​ ​ Equity in income of equity method joint venture investees ​ $ 130 ​ $ 294 ​ affiliated companies Interest rate swaps entered into by the Company's subsidiaries ​ ​ 992 ​ ​ 1,115 ​ Interest expense ​ ​ ​ ​ ​ ​ ​ ​ ​ Reclassifications of losses on discontinued hedging instruments ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swap entered into by the Company's subsidiaries ​ ​ 582 ​ ​ — ​ Interest expense ​ ​ ​ ​ ​ ​ ​ ​ ​ Reclassifications of losses on other-than-insignificant ​ ​ ​ ​ ​ ​ ​ ​ financing element of derivatives: ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swaps entered into by the Company's subsidiaries ​ ​ — ​ ​ 1,593 ​ Interest expense Total before and net of tax ​ $ 1,704 ​ $ 3,002 ​ ​ ​ At March 31, 2022, the Company expects that it will reclassify $12 thousand (gross and net of tax) of net losses on derivative instruments from accumulated other comprehensive loss to earnings during the next twelve months due to the payment of variable rate interest associated with floating rate debt of INSW’s equity method investees and the interest rate swaps held by the Company. ​ See Note 9, “Fair Value of Financial Instruments, Derivatives and Fair Value Disclosures,” for additional disclosures relating to derivative instruments.

REVENUE

REVENUE	3 Months Ended
	Mar. 31, 2022
REVENUE [Abstract]
REVENUE	Note 14 — Revenue: ​ Revenue Recognition ​ The majority of the Company's contracts for pool revenues, time and bareboat charter revenues, and voyage charter revenues are accounted for as lease revenue under ASC 842. The Company's contracts with pools are short term which are cancellable with up to 90 days' notice. As of March 31, 2022, the Company is a party to time charter out contracts with customers on one LR2, one Suezmax, one MR and one VLCC with expiry dates ranging from April 2022 to March 2023. The Company is also a party to a short-term profit share agreement to participate in a share of the profits and losses generated from a chartered-in MR commercially managed by a pool in which the Company participates. The Company’s share of earnings and charter hire expenses from this profit share agreement are included in voyage charter revenues and charter hire expenses, respectively, in the accompanying condensed consolidated statements of operations. The Company's contracts with customers for voyage charters are short term and vary in length based upon the duration of each voyage. Lease revenue for non-variable lease payments are recognized over the lease term on a straight-line basis and lease revenue for variable lease payments (e.g., demurrage) are recognized in the period in which the changes in facts and circumstances on which the variable lease payments are based occur. ​ Lightering services provided by the Company's Crude Tanker Lightering Business, and voyage charter contracts that do not meet the definition of a lease are accounted for as service revenues under ASC 606. In accordance with ASC 606, revenue is recognized when a customer obtains control of or consumes promised services. The amount of revenue recognized reflects the consideration to which the Company expects to be entitled to receive in exchange for these services. ​ ​ The following table presents the Company’s revenues from leases accounted for under ASC 842 and revenues from services accounted for under ASC 606 for the three months ended March 31, 2022 and 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Crude ​ Product ​ ​ ​ (Dollars in thousands) ​ Tankers ​ Carriers ​ Totals Three months ended March 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues from leases ​ ​ ​ ​ ​ ​ ​ ​ ​ Pool revenues ​ $ 27,310 ​ $ 56,452 ​ $ 83,762 Time and bareboat charter revenues ​ ​ 3,724 ​ ​ 2,451 ​ ​ 6,175 Voyage charter revenues from non-variable lease payments ​ ​ 2,844 ​ ​ 3,047 ​ ​ 5,891 Voyage charter revenues from variable lease payments ​ ​ 14 ​ ​ (78) ​ ​ (64) Revenues from services ​ ​ ​ ​ ​ ​ ​ ​ ​ Voyage charter revenues from lightering services ​ ​ 5,718 ​ ​ — ​ ​ 5,718 Total shipping revenues ​ $ 39,610 ​ $ 61,872 ​ $ 101,482 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues from leases ​ ​ ​ ​ ​ ​ ​ ​ ​ Pool revenues ​ $ 17,658 ​ $ 7,001 ​ $ 24,659 Time and bareboat charter revenues ​ ​ 13,078 ​ ​ 1,620 ​ ​ 14,698 Voyage charter revenues from non-variable lease payments (1) ​ ​ 940 ​ ​ 574 ​ ​ 1,514 Voyage charter revenues from variable lease payments ​ ​ – ​ ​ 51 ​ ​ 51 Revenues from services ​ ​ ​ ​ ​ ​ ​ ​ ​ Voyage charter revenues from lightering services ​ ​ 5,834 ​ ​ — ​ ​ 5,834 Total shipping revenues ​ $ 37,510 ​ $ 9,246 ​ $ 46,756 (1) Includes $0.5 million of loss of hire proceeds received during the three months ended March 31, 2021 . ​ Contract Balances ​ The following table provides information about receivables, contract assets and contract liabilities from contracts with customers, and significant changes in contract assets and liabilities balances, associated with revenue from services accounted for under ASC 606. Balances related to revenues from leases accounted for under ASC 842 are excluded from the table below. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Voyage receivables - Billed receivables ​ Contract assets (Unbilled voyage receivables) ​ Contract liabilities (Deferred revenues and off hires) Opening balance as of January 1, 2022 ​ $ 2,306 ​ ​ 225 ​ $ — Closing balance as of March 31, 2022 ​ ​ 2,018 ​ ​ 185 ​ ​ — ​ We receive payments from customers based on the schedule established in our contracts. Contract assets relate to our conditional right to consideration for our completed performance obligations under contracts and decrease when the right to consideration becomes unconditional or payments are received. Contract liabilities include payments received in advance of performance under contracts and are recognized when performance under the respective contract has been completed. Deferred revenues allocated to unsatisfied performance obligations will be recognized over time as the services are performed. ​ Performance Obligations ​ All of the Company’s performance obligations, and associated revenue, are generally transferred to customers over time. The expected duration of services is less than one year. Adjustments to revenue primarily relate to changes in estimates of performance obligations related to voyage charters. Adjustments in revenues from performance obligations satisfied in previous periods recognized were nil during the three months ended March 31, 2022 and 2021, respectively. ​ Costs to Obtain or Fulfill a Contract ​ As of March 31, 2022, there were no unamortized deferred costs of obtaining or fulfilling a contract.

LEASES

LEASES	3 Months Ended
	Mar. 31, 2022
LEASES [Abstract]
LEASES	Note 15 — Leases: ​ As permitted under ASC 842, the Company has elected not to apply the provisions of ASC 842 to short term leases, which include: (i) tanker vessels chartered-in where the duration of the charter was one year or less at inception; (ii) workboats employed in the Crude Tankers Lightering business which have a lease term of 12-months or less; and (iii) short term leases of office and other space. ​ Contracts under which the Company is a Lessee ​ The Company currently has two major categories of leases - chartered-in vessels and leased office and other space. The expenses recognized during the three months ended March 31, 2022 and 2021 for the lease component of these leases are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Operating lease cost ​ ​ ​ ​ ​ ​ Vessel assets ​ ​ ​ ​ ​ ​ Charter hire expenses ​ $ 2,418 ​ $ 2,421 ​ ​ ​ ​ ​ ​ ​ Office and other space ​ ​ ​ ​ ​ ​ General and administrative ​ ​ 227 ​ ​ 273 Voyage expenses ​ ​ 43 ​ ​ 42 ​ ​ ​ ​ ​ ​ ​ Short-term lease cost ​ ​ ​ ​ ​ ​ Vessel assets (1) ​ ​ ​ ​ ​ ​ Charter hire expenses ​ ​ 1,479 ​ ​ 901 Total lease cost ​ $ 4,167 ​ $ 3,637 (1) Excludes vessels spot chartered-in under operating leases and employed in the Crude Tankers Lightering business for periods of less than one month each, totaling $0.4 million and $0.1 million for the three months ended March 31, 2022 and 2021, respectively , including both lease and non-lease components. ​ Supplemental cash flow information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Cash paid for amounts included in the measurement of lease liabilities ​ ​ ​ ​ ​ ​ Operating cash flows used for operating leases ​ $ 2,486 ​ $ 2,736 ​ ​ Supplemental balance sheet information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ March 31, 2022 ​ December 31, 2021 Operating lease right-of-use assets ​ $ 23,425 ​ $ 23,168 ​ ​ ​ ​ ​ ​ ​ Current portion of operating lease liabilities ​ $ (10,767) ​ $ (8,393) Long-term operating lease liabilities ​ ​ (10,814) ​ ​ (12,522) Total operating lease liabilities ​ $ (21,581) ​ $ (20,915) ​ ​ ​ ​ ​ ​ ​ Weighted average remaining lease term - operating leases ​ ​ 4.84 years ​ ​ 5.15 years Weighted average discount rate - operating leases ​ ​ 5.16% ​ ​ 5.42% ​ 1. Charters-in of vessel assets: ​ As of March 31, 2022, INSW had commitments to charter in two Aframaxes and two LR1s. and the two LR1s are time charters April 2023 ​ Payments of lease liabilities and related number of operating days under these operating leases as of March 31, 2022 are as follows: ​ Bareboat Charters-in: ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Amount ​ Operating Days 2022 ​ $ 4,730 ​ 550 2023 ​ ​ 4,532 ​ 556 Total lease payments ​ ​ 9,262 ​ 1,106 less imputed interest ​ ​ (494) ​ ​ Total operating lease liabilities ​ $ 8,768 ​ ​ ​ Time Charters-in: ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Amount ​ Operating Days 2022 ​ $ 3,592 ​ 550 2023 ​ ​ 1,381 ​ 210 Total lease payments (lease component only) ​ ​ 4,973 ​ 760 less imputed interest ​ ​ (56) ​ ​ Total operating lease liabilities ​ $ 4,917 ​ ​ ​ 2. Office and other space: ​ The Company has operating leases for offices and lightering workboat dock space. These leases have expiry dates ranging from July 2023 to May 2033. The lease for the workboat dock space contains renewal options executable by the Company for periods through December 2027. We have determined that the options through December 2024 are reasonably certain to be executed by the Company, and accordingly the options are included in the lease liability and right of use asset calculations for such lease. ​ ​ Payments of lease liabilities for office and other space as of March 31, 2022 are as follows: ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ Amount 2022 ​ $ 205 2023 ​ ​ 229 2024 ​ ​ 973 2025 ​ ​ 998 2026 ​ ​ 1,024 Thereafter ​ ​ 6,907 Total lease payments ​ ​ 10,336 less imputed interest ​ ​ (2,440) Total operating lease liabilities ​ $ 7,896 ​ Contracts under which the Company is a Lessor ​ See Note 14, “Revenue,” for discussion on the Company’s revenues from operating leases accounted for under ASC 842. ​ The future minimum revenues, before reduction for brokerage commissions, expected to be received on non-cancelable time charters for one LR2, one Suezmax, one MR and one VLCC and the related revenue days as of March 31, 2022 are as follows: ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Amount ​ Revenue Days 2022 ​ $ 19,304 ​ 603 2023 ​ ​ 3,240 ​ 72 Future minimum revenues ​ $ 22,544 ​ 675 ​ Future minimum revenues do not include (i) the Company’s share of time charters entered into by the pools in which it participates, and (ii) the Company’s share of time charters entered into by the joint ventures, which the Company accounts for under the equity method. Revenues from a time charter are not generally received when a vessel is off-hire, including time required for normal periodic maintenance of the vessel. In arriving at the minimum future charter revenues, an estimated time off-hire to perform periodic maintenance on each vessel has been deducted, although there is no assurance that such estimate will be reflective of the actual off-hire in the future.

CONTINGENCIES

CONTINGENCIES	3 Months Ended
	Mar. 31, 2022
CONTINGENCIES [Abstract]
CONTINGENCIES	Note 16 — Contingencies: ​ INSW’s policy for recording legal costs related to contingencies is to expense such legal costs as incurred. ​ Multi-Employer Plans ​ The Merchant Navy Officers Pension Fund (“MNOPF”) is a multi-employer defined benefit pension plan covering British crew members that served as officers on board INSW’s vessels (as well as vessels of other owners). The trustees of the plan have indicated that, under the terms of the High Court ruling in 2005, which established the liability of past employers to fund the deficit on the Post 1978 section of MNOPF, calls for further contributions may be required if additional actuarial deficits arise or if other employers liable for contributions are not able to pay their share in the future. As the amount of any such assessment cannot be reasonably estimated, no reserves have been recorded for this contingency in INSW’s consolidated financial statements as of March 31, 2022. Assuming that the preliminary results of the deficit valuation as of March 31, 2021 are confirmed during 2022, showing that no deficit contributions would be required, the next deficit valuation will be as of March 31, 2024. ​ The Merchant Navy Ratings Pension Fund (“MNRPF”) is a multi-employer defined benefit pension plan covering British crew members that served as ratings (seamen) on board INSW’s vessels (as well as vessels of other owners) more than 20 years ago. Participating employers include current employers, historic employers that have made voluntary contributions, and historic employers such as INSW that have made no deficit contributions. Calls for contributions may be required if additional actuarial deficits arise or if other employers liable for contributions are unable to pay their share in the future. As the amount of any such assessment cannot be reasonably estimated, no reserves have been recorded in INSW’s consolidated financial statements as of March 31, 2022. The next deficit valuation will be as of March 31, 2023. ​ Spin-Off Related Agreements On November 30, 2016, INSW was spun off from OSG as a separate publicly traded company. In connection with the spin-off, INSW and OSG entered into several agreements, including a separation and distribution agreement, an employee matters agreement and a transition services agreement. While most of the obligations under those agreements were subsequently fulfilled, certain provisions (including in particular mutual indemnification provisions under the separation and distribution agreement and the employee matters agreement) continue in force. ​ Legal Proceedings Arising in the Ordinary Course of Business ​ The Company is a party, as plaintiff or defendant, to various suits in the ordinary course of business for monetary relief arising principally from personal injuries, wrongful death, collision or other casualty and to claims arising under charter parties and other contract disputes. A substantial majority of such personal injury, wrongful death, collision or other casualty claims against the Company are covered by insurance (subject to deductibles not material in amount). Each of the claims involves an amount which, in the opinion of management, should not be material to the Company’s financial position, results of operations and cash flows.

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2022
SIGNIFICANT ACCOUNTING POLICIES [Abstract]
Cash, cash equivalents and restricted cash	Cash, cash equivalents and restricted cash —
Concentration of Credit Risk	​ Concentration of Credit Risk — ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ Allowance for Credit Losses - Balance at December 31, 2021 ​ $ 31 Reversal of expected credit losses ​ ​ (4) Balance at March 31, 2022 ​ $ 27 ​ We are also exposed to credit losses from off-balance sheet exposures related to guarantees of joint venture debt. See Note 7, “Equity Method Investments,” for more information on these off-balance sheet exposures. ​ During the three months ended March 31, 2022 and 2021, the Company did not have any individual customers who accounted for 10% or more of its revenues apart from the pools in which it participates. The pools in which the Company participates accounted in aggregate for 94% and 93% of consolidated voyage receivables at March 31, 2022 and December 31, 2021, respectively.
Deferred finance charges	Deferred finance charges —
Vessels construction in progress	Vessels construction in progress —
Time Charter Contracts Acquired	Time Charter Contracts Acquired —
Recently adopted / issued accounting standards	Recently Issued Accounting Standards Reference Rate Reform which provides relief for companies preparing for discontinuation of interest rates such as LIBOR. A contract modification is eligible to apply the optional relief to account for the modifications as a continuation of the existing contracts without additional analysis and consider embedded features to be clearly and closely related to the host contract without reassessment, if all of the following criteria are met: (1) contract references a rate that will be discontinued; (2) modified terms directly replace (or have potential to replace) this reference rate; and (3) changes to any other terms that change (or have potential to change) amount and timing of cash flows must be related to replacement of the reference rate. In addition, this guidance provides relief from certain hedge accounting requirements. Hedge accounting may continue uninterrupted when critical terms change due to reference rate reform. For cash flow hedges, entities can (1) disregard potential discontinuation of a referenced interest rate when assessing whether a hedged forecasted interest payment is probable; (2) continue hedge accounting upon a change in the hedged risk as long as the hedge is still highly effective; (3) assess effectiveness of the hedge relationship in ways that essentially disregards a potential mismatch in the variable rate indices between the hedging instrument and the hedged item; and (4) disregard the requirement that individual hedged transactions must share the same risk exposure for hedges of portfolios of forecasted transactions that reference a rate affected by reference rate reform. Relief provided by this ASU is optional and expires December 31, 2022. In January 2021, the FASB issued ASU 2021-01, Reference Rate Reform (ASC 848) to refine the scope of ASC 848 and to clarify some of its guidance. The Company has determined that its primary exposure to LIBOR is in relation to its floating rate debt facilities and the interest rate derivatives to which it is a party. On November 30, 2020, the benchmark administrator for the U.S. Dollar (“USD”) LIBOR announced a proposal to extend the publication of the most commonly used USD LIBOR settings until June 30, 2023. In light of this proposal, in an interagency statement, the Board of Governors of the Federal Reserve System, the Federal Deposit Insurance Corporation, and the Office of the Comptroller of the Currency issued guidance, strongly encouraging banks to cease entering into new contracts that use USD LIBOR as a reference rate as soon as practicable and in any event by December 31, 2021. Only in limited circumstances will it be appropriate for banks to enter into new contracts referencing USD LIBOR after December 31, 2021. The principal objective, and result, of these actions appears to be that legacy USD LIBOR-based instruments (i.e., those maturing after December 31, 2021) may continue to use USD LIBOR as a reference rate through June 30, 2023, without undermining the regulators’ determination that LIBOR should not be available for any other purpose. On January 25, 2021, the International Swaps and Derivatives Association, Inc. (“ISDA”), published new fallback provisions for derivatives linked to key interbank offered rates (“IBOR”) which will be incorporated into all new derivatives contracts that reference ISDA’s standard interest rate derivatives definitions. Such fallback provisions will also be included in legacy non-cleared derivatives if the counterparties have bilaterally agreed to include them or both have adhered to the IBOR fallback protocol. The Company has engaged and will continue to engage in discussions with its lending banks and the counterparties to its interest rate derivative contracts in advance of the June 30, 2023 sunset date for the USD LIBOR reference rate settings used in its agreements to evaluate the Company’s options. Based on information available today, the Company’s current view is that the Secured Overnight Financing Rate (“SOFR”) will be the alternative reference rate that the Company’s LIBOR-based agreements will transition to as the sunset date draws closer.

CONTINGENCIES (Policy)

CONTINGENCIES (Policy)	3 Months Ended
	Mar. 31, 2022
CONTINGENCIES [Abstract]
Legal costs	​ INSW’s policy for recording legal costs related to contingencies is to expense such legal costs as incurred.

SIGNIFICANT ACCOUNTING POLICI_2

SIGNIFICANT ACCOUNTING POLICIES (Tables)	3 Months Ended
	Mar. 31, 2022
SIGNIFICANT ACCOUNTING POLICIES [Abstract]
Activity for allowance for credit losses	​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ Allowance for Credit Losses - Balance at December 31, 2021 ​ $ 31 Reversal of expected credit losses ​ ​ (4) Balance at March 31, 2022 ​ $ 27

EARNINGS PER COMMON SHARE (Tabl

EARNINGS PER COMMON SHARE (Tables)	3 Months Ended
	Mar. 31, 2022
EARNINGS PER COMMON SHARE [Abstract]
Components of Calculation of Earnings Per Share	​ Reconciliations of the numerator of the basic and diluted earnings per share computations are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Net (loss)/income attributable to the Company allocated to: ​ ​ ​ ​ ​ ​ Common Stockholders ​ $ (13,006) ​ $ (13,368) Participating securities ​ ​ 5 ​ ​ 3 ​ ​ $ (13,001) ​ $ (13,365)

BUSINESS AND SEGMENT REPORTING

BUSINESS AND SEGMENT REPORTING (Tables)	3 Months Ended
	Mar. 31, 2022
BUSINESS AND SEGMENT REPORTING [Abstract]
Schedule of Segment Reporting Information, by Segment	​ Information about the Company’s reportable segments as of and for the three months ended March 31, 2022 and 2021 follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Crude ​ Product ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Tankers ​ Carriers ​ Other ​ Totals Three months ended March 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Shipping revenues ​ $ 39,610 ​ $ 61,872 ​ $ — ​ $ 101,482 Time charter equivalent revenues ​ ​ 36,475 ​ ​ 61,500 ​ ​ — ​ ​ 97,975 Depreciation and amortization ​ ​ 15,152 ​ ​ 11,841 ​ ​ 7 ​ ​ 27,000 Loss/(gain) on disposal of vessels and other assets, including impairments ​ ​ 1,843 ​ ​ (3,219) ​ ​ — ​ ​ (1,376) Adjusted income/(loss) from vessel operations ​ ​ (5,842) ​ ​ 9,198 ​ ​ (7) ​ ​ 3,349 Equity in income of affiliated companies ​ ​ 5,597 ​ ​ — ​ ​ — ​ ​ 5,597 Investments in and advances to affiliated companies at March 31, 2022 ​ ​ 160,298 ​ ​ 23,063 ​ ​ — ​ ​ 183,361 Adjusted total assets at March 31, 2022 ​ ​ 1,465,035 ​ ​ 803,077 ​ ​ — ​ ​ 2,268,112 Expenditures for vessels and vessel improvements ​ ​ 14,608 ​ ​ 23,381 ​ ​ — ​ ​ 37,989 Payments for drydocking ​ ​ 7,660 ​ ​ 9,910 ​ ​ — ​ ​ 17,570 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Shipping revenues ​ $ 37,510 ​ $ 9,246 ​ $ — ​ $ 46,756 Time charter equivalent revenues ​ ​ 35,950 ​ ​ 9,219 ​ ​ — ​ ​ 45,169 Depreciation and amortization ​ ​ 13,003 ​ ​ 3,728 ​ ​ 23 ​ ​ 16,754 Loss on disposal of vessels and other assets ​ ​ 11 ​ ​ — ​ ​ — ​ ​ 11 Adjusted loss from vessel operations ​ ​ (957) ​ ​ (2,673) ​ ​ (23) ​ ​ (3,653) Equity in income of affiliated companies ​ ​ 5,468 ​ ​ — ​ ​ — ​ ​ 5,468 Investments in and advances to affiliated companies at March 31, 2021 ​ ​ 137,361 ​ ​ 7,409 ​ ​ — ​ ​ 144,770 Adjusted total assets at March 31, 2021 ​ ​ 1,115,421 ​ ​ 255,220 ​ ​ — ​ ​ 1,370,641 Expenditures for vessels and vessel improvements ​ ​ 2,666 ​ ​ 615 ​ ​ — ​ ​ 3,281 Payments for drydocking ​ ​ 3,088 ​ ​ 5,506 ​ ​ — ​ ​ 8,594 ​
Reconciliation of Revenue from Segments to Consolidated	Reconciliations of time charter equivalent (“TCE”) revenues of the segments to shipping revenues as reported in the condensed statements of operations follow: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Time charter equivalent revenues ​ $ 97,975 ​ $ 45,169 Add: Voyage expenses ​ ​ 3,507 ​ ​ 1,587 Shipping revenues ​ $ 101,482 ​ $ 46,756 ​
Reconciliation of Operating Profit (Loss) from Segments to Consolidated	Reconciliations of adjusted income/(loss) from vessel operations of the segments to loss before income taxes, as reported in the condensed consolidated statements of operations follow: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Total adjusted income/(loss) from vessel operations of all segments ​ $ 3,349 ​ $ (3,653) General and administrative expenses ​ ​ (10,166) ​ ​ (8,181) Third-party debt modification fees ​ ​ (187) ​ ​ — Gain/(loss) on disposal of vessels and other assets, including impairments ​ ​ 1,376 ​ ​ (11) Consolidated loss from vessel operations ​ ​ (5,628) ​ ​ (11,845) Equity in income of affiliated companies ​ ​ 5,597 ​ ​ 5,468 Other (expense)/income ​ ​ (226) ​ ​ 292 Interest expense ​ ​ (12,740) ​ ​ (7,280) Loss before income taxes ​ $ (12,997) ​ $ (13,365) ​
Reconciliation of Assets from Segment to Consolidated	Reconciliations of total assets of the segments to amounts included in the condensed consolidated balance sheets follow: ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ March 31, 2022 ​ March 31, 2021 Adjusted total assets of all segments ​ $ 2,268,112 ​ $ 1,370,641 Corporate unrestricted cash and cash equivalents ​ ​ 74,553 ​ ​ 156,178 Restricted cash ​ ​ 1,051 ​ ​ 16,223 Other unallocated amounts ​ ​ 22,877 ​ ​ 9,010 Consolidated total assets ​ $ 2,366,593 ​ $ 1,552,052

EQUITY METHOD INVESTMENTS (Tabl

EQUITY METHOD INVESTMENTS (Tables)	3 Months Ended
	Mar. 31, 2022
EQUITY METHOD INVESTMENTS [Abstract]
Results of Operations of Equity Method Investments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Shipping revenues ​ $ 25,887 ​ $ 25,846 Ship operating expenses ​ ​ (14,292) ​ ​ (13,931) Income from vessel operations ​ ​ 11,595 ​ ​ 11,915 Interest expense ​ ​ (543) ​ ​ (1,212) Income tax provision ​ ​ (1,029) ​ ​ (993) Net income ​ $ 10,023 ​ $ 9,710

VARIABLE INTEREST ENTITIES (V_2

VARIABLE INTEREST ENTITIES (VIEs) (Tables)	3 Months Ended
	Mar. 31, 2022
VARIABLE INTEREST ENTITIES (VIEs) [Abstract]
Schedule of Variable Interest Entities	​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ ​ ​ Condensed Investments in Affiliated Companies ​ ​ ​ ​ $ 181,960
Schedule of Variable Interest Entities Liability in Condensed Consolidated Balance Sheet to Maximum Exposure to Loss	​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ Condensed ​ Maximum Exposure to Other Liabilities ​ $ – ​ $ 195,271

FAIR VALUE OF FINANCIAL INSTR_2

FAIR VALUE OF FINANCIAL INSTRUMENTS, DERIVATIVES AND FAIR VALUE DISCLOSURES (Tables)	3 Months Ended
	Mar. 31, 2022
FAIR VALUE OF FINANCIAL INSTRUMENTS, DERIVATIVES AND FAIR VALUE DISCLOSURES [Abstract]
Fair Value, by Balance Sheet Grouping	The estimated fair values of the Company’s financial instruments, other than derivatives that are not measured at fair value on a recurring basis, categorized based upon the fair value hierarchy, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ March 31, 2022 ​ December 31, 2021 ​ Fair Value Level Cash and cash equivalents (1) ​ $ 75,604 ​ $ 98,933 ​ ​ Level 1 $390 Million Facility Term Loan ​ ​ (172,766) ​ ​ (191,050) ​ ​ Level 2 $525 Million Facility Term Loan ​ ​ (198,265) ​ ​ (216,289) ​ ​ Level 2 $525 Million Facility Revolving Loan ​ ​ (94,193) ​ ​ (44,193) ​ ​ Level 2 $360 Million Facility Term Loan ​ ​ (96,413) ​ ​ (105,325) ​ ​ Level 2 $360 Million Facility Revolving Loan ​ ​ (38,889) ​ ​ (38,889) ​ ​ Level 2 Macquarie Credit Facility ​ ​ (18,950) ​ ​ (19,475) ​ ​ Level 2 ING Credit Facility ​ ​ (24,479) ​ ​ (25,000) ​ ​ Level 2 Ocean Yield Lease Financing ​ ​ (363,105) ​ ​ (370,305) ​ ​ Level 2 BoComm Lease Financing ​ ​ (14,411) ​ ​ (9,608) ​ ​ Level 2 Toshin Lease Financing ​ ​ (16,677) ​ ​ (16,995) ​ ​ Level 2 Hyuga Lease Financing ​ ​ (16,386) ​ ​ n/a ​ ​ Level 2 COSCO Lease Financing ​ ​ (51,493) ​ ​ (52,746) ​ ​ Level 2 8.5% Senior Notes ​ ​ (25,833) ​ ​ (25,940) ​ ​ Level 1 (1) Includes restricted cash of $1.1 million at March 31, 2022 and December 31, 2021, respectively. ​
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Current portion of derivative asset ​ Long-term derivative ​ Current portion of derivative liabilities ​ Long-term derivative March 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivatives designated as hedging instruments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swaps ​ $ 2,061 ​ $ 5,959 ​ $ — ​ $ — Total ​ $ 2,061 ​ $ 5,959 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivatives designated as hedging instruments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swaps ​ $ — ​ $ 1,296 ​ $ (2,539) ​ $ (757) Total ​ $ — ​ $ 1,296 ​ $ (2,539) ​ $ (757) ​
Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Loss	The effect of cash flow hedging relationships recognized in other comprehensive income excluding amounts reclassified from accumulated other comprehensive loss, including hedges of equity method investees, for the three months ended March 31, 2022 and 2021 follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Derivatives designated as hedging instruments: ​ ​ ​ ​ ​ ​ Interest rate swaps ​ $ 9,058 ​ $ 7,747 ​ ​ ​ ​ ​ ​ ​ Other-than-insignificant financing element of derivatives: ​ ​ ​ ​ ​ ​ Interest rate swaps ​ ​ — ​ ​ (466) Total other comprehensive income ​ $ 9,058 ​ $ 7,281 ​ The effect of cash flow hedging relationships on the condensed consolidated statement of operations is presented excluding hedges of equity method investees. The effect of the Company’s cash flow hedging relationships on the condensed consolidated statement of operations for the three months ended March 31, 2022 and 2021 follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Derivatives designated as hedging instruments: ​ ​ ​ ​ ​ ​ Interest rate swaps ​ $ 992 ​ $ 1,115 ​ ​ ​ ​ ​ ​ ​ Discontinued hedging instruments: ​ ​ ​ ​ ​ ​ Interest rate swap ​ ​ 582 ​ ​ — ​ ​ ​ ​ ​ ​ ​ Other-than-insignificant financing element of derivatives: ​ ​ ​ ​ ​ ​ Interest rate swaps ​ ​ — ​ ​ 1,593 Total interest expense ​ $ 1,574 ​ $ 2,708 ​
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following table presents the fair values, which are pre-tax, for assets and liabilities measured on a recurring basis (excluding investments in affiliated companies): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ March 31, 2022 ​ December 31, 2021 ​ Fair Value Level Derivative Assets (interest rate swaps) ​ $ 8,020 ​ $ 1,296 ​ ​ Level 2 (1) Derivative Liabilities (interest rate swaps) ​ ​ — ​ ​ (3,296) ​ ​ Level 2 (1) (1) For the interest rate swaps, fair values are derived using valuation models that utilize the income valuation approach. These valuation models take into account contract terms such as maturity, as well as other inputs such as interest rate yield curves and creditworthiness of the counterparty and the Company.
Schedule of Fair Value, Assets and Liabilities Measured on Nonrecurring Basis	The following table summarizes the fair values of assets for which impairment charges were recognized for the three months ended March 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ Fair Value ​ ​ Level 2 ​ ​ Total Impairment Crude Tankers - Vessels held for sale (1)(2) ​ $ 7,561 ​ $ 7,561 ​ $ (1,019) Product Carriers - Vessels held for sale (1) (2) ​ ​ 9,850 ​ ​ 9,850 ​ ​ (207) Product Carriers - Vessels held for use (1) (2) ​ ​ 9,575 ​ ​ 9,575 ​ ​ (471) (1) A pre-tax held for sale impairment charge of $1.0 million related to one Panamax in the Crude Tankers segment was recorded during the three months ended March 31, 2022, including a charge of $0.9 million to write the value of the vessel down to its estimated fair value, and estimated costs to sell the vessel of $0.1 million. A pre-tax held for sale impairment charge of $0.2 million related to one MR in the Product Carriers segment was recorded during the three months ended March 31, 2022, consisting of $0.2 million costs to sell the vessel. A pre-tax held for use impairment charge of $0.5 million related to one Handysize product carrier was recorded during the three months ended March 31, 2022 to write the value of the vessel down to its estimated fair value. (2) Fair value measurement of $27.0 million at March 31, 2022 used to determine the impairments for the vessels was based upon a market approach, which considered the expected sale prices of the vessels based on the executed memoranda of agreements as discussed in Note 6, "Vessels." The expected sales prices are considered to be Level 2 because sales of vessels occur somewhat infrequently .

DEBT (Tables)

DEBT (Tables)	3 Months Ended
	Mar. 31, 2022
DEBT [Abstract]
Schedule of Long-term Debt Instruments	​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ March 31, 2022 December 31, 2021 $390 Million Facility Term Loan, due 2025, net of unamortized deferred finance costs of $1,997 and $2,357 ​ $ 170,769 ​ $ 188,693 $525 Million Facility Term Loan, due 2024 ​ ​ 198,265 ​ ​ 216,289 $525 Million Facility Revolving Loan, due 2024 ​ ​ 94,193 ​ ​ 44,193 $360 Million Facility Term Loan, due 2024 ​ ​ 96,413 ​ ​ 105,325 $360 Million Facility Revolving Loan, due 2024 ​ ​ 38,889 ​ ​ 38,889 Macquarie Credit Facility, due 2025, net of unamortized deferred finance costs of $706 and $755 ​ ​ 18,244 ​ ​ 18,720 ING Credit Facility, due 2026, net of unamortized deferred finance costs of $513 and $546 ​ ​ 23,966 ​ ​ 24,454 Ocean Yield Lease Financing, due 2031, net of unamortized deferred finance costs of $3,632 and $3,799 ​ ​ 359,474 ​ ​ 366,506 BoComm Lease Financing, due 2030, net of unamortized deferred finance costs of $150 and $114 ​ ​ 14,261 ​ ​ 9,494 Toshin Lease Financing, due 2031, net of unamortized deferred finance costs of $417 and $428 ​ ​ 16,260 ​ ​ 16,567 COSCO Lease Financing, due 2028, net of unamortized deferred finance costs of $1,375 and $1,353 ​ ​ 50,118 ​ ​ 51,393 Hyuga Lease Financing, due 2031, net of unamortized deferred finance costs of $361 ​ ​ 16,025 ​ ​ — 8.5% Senior Notes, due 2023, net of unamortized deferred finance costs of $454 and $538 ​ ​ 24,546 ​ ​ 24,462 ​ ​ ​ 1,121,423 ​ ​ 1,104,985 Less current portion ​ ​ (178,391) ​ ​ (178,715) Long-term portion ​ $ 943,032 ​ $ 926,270

ACCUMULATED OTHER COMPREHENSI_2

ACCUMULATED OTHER COMPREHENSIVE LOSS (Tables)	3 Months Ended
	Mar. 31, 2022
ACCUMULATED OTHER COMPREHENSIVE LOSS [Abstract]
Components of Accumulated Other Comprehensive Loss	The components of accumulated other comprehensive loss, net of related taxes, in the condensed consolidated balance sheets follow: ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ March 31, 2022 December 31, 2021 Unrealized gains/(losses) on derivative instruments ​ $ 5,899 ​ $ (4,863) Items not yet recognized as a component of net periodic benefit cost (pension plans) ​ ​ (7,300) ​ ​ (7,497) ​ ​ $ (1,401) ​ $ (12,360) ​ The changes in the balances of each component of accumulated other comprehensive loss, net of related taxes, during the three months ended March 31, 2022 and 2021 follow: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Unrealized gains/(losses) on cash flow hedges ​ Items not yet recognized as a component of net periodic benefit cost ​ Total Balance as of December 31, 2021 ​ $ (4,863) ​ $ (7,497) ​ $ (12,360) Current period change, excluding amounts reclassified ​ ​ ​ ​ ​ ​ ​ ​ ​ from accumulated other comprehensive loss ​ ​ 9,058 ​ ​ 197 ​ ​ 9,255 Amounts reclassified from accumulated other comprehensive loss ​ ​ 1,704 ​ ​ — ​ ​ 1,704 Balance as of March 31, 2022 ​ $ 5,899 ​ $ (7,300) ​ $ (1,401) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, 2020 ​ $ (24,098) ​ ​ (8,515) ​ ​ (32,613) Current period change, excluding amounts reclassified ​ ​ ​ ​ ​ ​ ​ ​ ​ from accumulated other comprehensive loss ​ ​ 7,281 ​ ​ (64) ​ ​ 7,217 Amounts reclassified from accumulated other comprehensive loss ​ ​ 3,002 ​ ​ — ​ ​ 3,002 Balance as of March 31, 2021 ​ $ (13,815) ​ $ (8,579) ​ $ (22,394) ​
Reclassification Out of Accumulated Other Comprehensive Income (Loss)	​ Amounts reclassified out of each component of accumulated other comprehensive loss follow: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 ​ Statement of Operations Reclassifications of losses on cash flow hedges: ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swaps entered into by the Company's ​ ​ ​ ​ ​ ​ ​ Equity in income of equity method joint venture investees ​ $ 130 ​ $ 294 ​ affiliated companies Interest rate swaps entered into by the Company's subsidiaries ​ ​ 992 ​ ​ 1,115 ​ Interest expense ​ ​ ​ ​ ​ ​ ​ ​ ​ Reclassifications of losses on discontinued hedging instruments ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swap entered into by the Company's subsidiaries ​ ​ 582 ​ ​ — ​ Interest expense ​ ​ ​ ​ ​ ​ ​ ​ ​ Reclassifications of losses on other-than-insignificant ​ ​ ​ ​ ​ ​ ​ ​ financing element of derivatives: ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swaps entered into by the Company's subsidiaries ​ ​ — ​ ​ 1,593 ​ Interest expense Total before and net of tax ​ $ 1,704 ​ $ 3,002 ​ ​ ​

REVENUE (Tables)

REVENUE (Tables)	3 Months Ended
	Mar. 31, 2022
REVENUE [Abstract]
Schedule of Disaggregated Revenue	​ The following table presents the Company’s revenues from leases accounted for under ASC 842 and revenues from services accounted for under ASC 606 for the three months ended March 31, 2022 and 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Crude ​ Product ​ ​ ​ (Dollars in thousands) ​ Tankers ​ Carriers ​ Totals Three months ended March 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues from leases ​ ​ ​ ​ ​ ​ ​ ​ ​ Pool revenues ​ $ 27,310 ​ $ 56,452 ​ $ 83,762 Time and bareboat charter revenues ​ ​ 3,724 ​ ​ 2,451 ​ ​ 6,175 Voyage charter revenues from non-variable lease payments ​ ​ 2,844 ​ ​ 3,047 ​ ​ 5,891 Voyage charter revenues from variable lease payments ​ ​ 14 ​ ​ (78) ​ ​ (64) Revenues from services ​ ​ ​ ​ ​ ​ ​ ​ ​ Voyage charter revenues from lightering services ​ ​ 5,718 ​ ​ — ​ ​ 5,718 Total shipping revenues ​ $ 39,610 ​ $ 61,872 ​ $ 101,482 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues from leases ​ ​ ​ ​ ​ ​ ​ ​ ​ Pool revenues ​ $ 17,658 ​ $ 7,001 ​ $ 24,659 Time and bareboat charter revenues ​ ​ 13,078 ​ ​ 1,620 ​ ​ 14,698 Voyage charter revenues from non-variable lease payments (1) ​ ​ 940 ​ ​ 574 ​ ​ 1,514 Voyage charter revenues from variable lease payments ​ ​ – ​ ​ 51 ​ ​ 51 Revenues from services ​ ​ ​ ​ ​ ​ ​ ​ ​ Voyage charter revenues from lightering services ​ ​ 5,834 ​ ​ — ​ ​ 5,834 Total shipping revenues ​ $ 37,510 ​ $ 9,246 ​ $ 46,756 (1) Includes $0.5 million of loss of hire proceeds received during the three months ended March 31, 2021 .
Schedule of Contract Related Receivables, Assets and Liabilities with Customers	​ The following table provides information about receivables, contract assets and contract liabilities from contracts with customers, and significant changes in contract assets and liabilities balances, associated with revenue from services accounted for under ASC 606. Balances related to revenues from leases accounted for under ASC 842 are excluded from the table below. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Voyage receivables - Billed receivables ​ Contract assets (Unbilled voyage receivables) ​ Contract liabilities (Deferred revenues and off hires) Opening balance as of January 1, 2022 ​ $ 2,306 ​ ​ 225 ​ $ — Closing balance as of March 31, 2022 ​ ​ 2,018 ​ ​ 185 ​ ​ — ​

LEASES (Tables)

LEASES (Tables)	3 Months Ended
	Mar. 31, 2022
Lease [Abstract]
Schedule of lease cost	The Company currently has two major categories of leases - chartered-in vessels and leased office and other space. The expenses recognized during the three months ended March 31, 2022 and 2021 for the lease component of these leases are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Operating lease cost ​ ​ ​ ​ ​ ​ Vessel assets ​ ​ ​ ​ ​ ​ Charter hire expenses ​ $ 2,418 ​ $ 2,421 ​ ​ ​ ​ ​ ​ ​ Office and other space ​ ​ ​ ​ ​ ​ General and administrative ​ ​ 227 ​ ​ 273 Voyage expenses ​ ​ 43 ​ ​ 42 ​ ​ ​ ​ ​ ​ ​ Short-term lease cost ​ ​ ​ ​ ​ ​ Vessel assets (1) ​ ​ ​ ​ ​ ​ Charter hire expenses ​ ​ 1,479 ​ ​ 901 Total lease cost ​ $ 4,167 ​ $ 3,637 (1) Excludes vessels spot chartered-in under operating leases and employed in the Crude Tankers Lightering business for periods of less than one month each, totaling $0.4 million and $0.1 million for the three months ended March 31, 2022 and 2021, respectively , including both lease and non-lease components.
Supplemental lease information	Supplemental cash flow information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) ​ ​ 2022 ​ ​ 2021 Cash paid for amounts included in the measurement of lease liabilities ​ ​ ​ ​ ​ ​ Operating cash flows used for operating leases ​ $ 2,486 ​ $ 2,736 ​ ​ Supplemental balance sheet information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ March 31, 2022 ​ December 31, 2021 Operating lease right-of-use assets ​ $ 23,425 ​ $ 23,168 ​ ​ ​ ​ ​ ​ ​ Current portion of operating lease liabilities ​ $ (10,767) ​ $ (8,393) Long-term operating lease liabilities ​ ​ (10,814) ​ ​ (12,522) Total operating lease liabilities ​ $ (21,581) ​ $ (20,915) ​ ​ ​ ​ ​ ​ ​ Weighted average remaining lease term - operating leases ​ ​ 4.84 years ​ ​ 5.15 years Weighted average discount rate - operating leases ​ ​ 5.16% ​ ​ 5.42%
Schedule of lease maturity receivables	The future minimum revenues, before reduction for brokerage commissions, expected to be received on non-cancelable time charters for one LR2, one Suezmax, one MR and one VLCC and the related revenue days as of March 31, 2022 are as follows: ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Amount ​ Revenue Days 2022 ​ $ 19,304 ​ 603 2023 ​ ​ 3,240 ​ 72 Future minimum revenues ​ $ 22,544 ​ 675
Office Space And Lightering Workboat Dock Space [Member]
Lease [Abstract]
Schedule of lease maturity payments	Payments of lease liabilities for office and other space as of March 31, 2022 are as follows: ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ Amount 2022 ​ $ 205 2023 ​ ​ 229 2024 ​ ​ 973 2025 ​ ​ 998 2026 ​ ​ 1,024 Thereafter ​ ​ 6,907 Total lease payments ​ ​ 10,336 less imputed interest ​ ​ (2,440) Total operating lease liabilities ​ $ 7,896
Bareboat Charters-In [Member]
Lease [Abstract]
Schedule of lease maturity payments	Payments of lease liabilities and related number of operating days under these operating leases as of March 31, 2022 are as follows: ​ Bareboat Charters-in: ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Amount ​ Operating Days 2022 ​ $ 4,730 ​ 550 2023 ​ ​ 4,532 ​ 556 Total lease payments ​ ​ 9,262 ​ 1,106 less imputed interest ​ ​ (494) ​ ​ Total operating lease liabilities ​ $ 8,768 ​ ​ ​
Time Charters-In [Member]
Lease [Abstract]
Schedule of lease maturity payments	Time Charters-in: ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Amount ​ Operating Days 2022 ​ $ 3,592 ​ 550 2023 ​ ​ 1,381 ​ 210 Total lease payments (lease component only) ​ ​ 4,973 ​ 760 less imputed interest ​ ​ (56) ​ ​ Total operating lease liabilities ​ $ 4,917 ​ ​ ​

BASIS OF PRESENTATION (Details)

BASIS OF PRESENTATION (Details)	Apr. 01, 2022property	Mar. 31, 2022segmentproperty
Property, Plant and Equipment [Line Items]
Number of reportable segments | segment		2
Vessel/Fleet [Member]
Property, Plant and Equipment [Line Items]
Number of vessels in fleet		87
Maritime Equipment Not Including New Builds [Member]
Property, Plant and Equipment [Line Items]
Number of vessels in fleet		84
Vessels with Interest In [Member]
Property, Plant and Equipment [Line Items]
Number of vessels in fleet		2
Maritime Equipment New Builds [Member]
Property, Plant and Equipment [Line Items]
Number of vessels in fleet		3
Panamaxes (LR1) [Member] | Subsequent Event [Member]
Property, Plant and Equipment [Line Items]
Number of Vessels Sold and Delivered	2
Handysize Product Carriers | Subsequent Event [Member]
Property, Plant and Equipment [Line Items]
Number of Vessels Sold and Delivered	1

MERGER TRANSACTION (Details)

MERGER TRANSACTION (Details)	Jul. 16, 2021USD ($)shares	Mar. 31, 2022itemshares	Dec. 31, 2021shares	Jul. 15, 2021USD ($)
Asset Acquisition [Line Items]
Special dividends that can be paid prior to the effective date under the business combination | $				$ 31,500,000
Asset acquisition special dividends per share costs | $	$ 1.12
Common stock, shares, issued	50,674,393	49,641,506	49,612,019
Common stock, shares, outstanding	50,674,393	49,641,506	49,612,019
Number of joint ventures | item		2
Diamond S Shareholders
Asset Acquisition [Line Items]
Percentage of outstanding shares	44.25%
Pre Merger International Seaways Shareholders [Member]
Asset Acquisition [Line Items]
Percentage of outstanding shares	55.75%
Diamond S Shipping Inc
Asset Acquisition [Line Items]
Asset acquisition conversion ratio of acquiree stock into acquirer stock	0.55375
Diamond S Shipping Inc | Common Stock [Member]
Asset Acquisition [Line Items]
Shares issued in asset acquisition	22,536,647

SIGNIFICANT ACCOUNTING POLICI_3

SIGNIFICANT ACCOUNTING POLICIES (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	$ 1,051	$ 16,223	$ 1,100
Amortization of financing costs	600	500
Amortization of Intangible Assets	340	$ 0
Maritime Equipment New Builds [Member]
Summary Of Significant Accounting Policies [Line Items]
Interest costs capitalized	700
$390 million Credit Facility
Summary Of Significant Accounting Policies [Line Items]
Debt instrument, face amount	$ 390,000
Revenue, Product and Service Benchmark [Member] | Product Concentration Risk [Member] | Pool Revenue Leases [Member]
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	94.00%		93.00%
Term loan | Core Term Loan Facility, Core Transition Facility, Sinosure Credit Facility and 8.5% Senior Notes [Member]
Summary Of Significant Accounting Policies [Line Items]
Deferred finance costs, gross	$ 9,600		$ 9,900
Revolving Credit Facility [Member] | Core Revolving Facility [Member]
Summary Of Significant Accounting Policies [Line Items]
Deferred finance costs, gross	$ 4,400		$ 3,700

SIGNIFICANT ACCOUNTING POLICI_4

SIGNIFICANT ACCOUNTING POLICIES (Activity for allowance for credit losses) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)
SIGNIFICANT ACCOUNTING POLICIES [Abstract]
Balance Beginning	$ 31
(Reversal of)/provision for expected credit losses	(4)
Balance Ending	$ 27

EARNINGS PER COMMON SHARE (Narr

EARNINGS PER COMMON SHARE (Narrative) (Details) - shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive awards	0	0
Restricted Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Participating securities allocated a portion of income	87,117	51,087
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities	196,473
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities	811,906
Antidilutive securities excluded from computation of earnings per share, amount	1,026,418	944,477

EARNINGS PER COMMON SHARE (Reco

EARNINGS PER COMMON SHARE (Reconciliation of Net Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
EARNINGS PER COMMON SHARE [Abstract]
Common Stockholders	$ (13,006)	$ (13,368)
Participating securities	5	3
Net (loss)/income	$ (13,001)	$ (13,365)

BUSINESS AND SEGMENT REPORTIN_2

BUSINESS AND SEGMENT REPORTING (Reportable Segments Information) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)propertysegment	Mar. 31, 2021USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment	2
Revenues, services	$ 101,482	$ 46,756
Time charter equivalent revenues	97,975	45,169
Depreciation and amortization	27,000	16,754
Loss/(gain) on disposal of vessels and other assets, including impairments	(1,376)	11
Adjusted income/(loss) from vessel operations	3,349	(3,653)
Equity in income/(loss) of affiliated companies	5,597	5,468
Investments in and advances to affiliated companies	183,361	144,770
Adjusted total assets	2,268,112	1,370,641
Expenditures for vessels and vessel improvements	37,989	3,281
Payments for drydocking	17,570	8,594
Time Charter Equivalent Services [Member]
Segment Reporting Information [Line Items]
Revenues, services	97,975
International Crude Tankers Segment [Member]
Segment Reporting Information [Line Items]
Revenues, services	39,610	37,510
Time charter equivalent revenues		35,950
Depreciation and amortization	15,152	13,003
Loss/(gain) on disposal of vessels and other assets, including impairments	1,843	11
Adjusted income/(loss) from vessel operations	(5,842)	(957)
Equity in income/(loss) of affiliated companies	5,597	5,468
Investments in and advances to affiliated companies	160,298	137,361
Adjusted total assets	1,465,035	1,115,421
Expenditures for vessels and vessel improvements	14,608	2,666
Payments for drydocking	$ 7,660	3,088
International Crude Tankers Segment [Member] | Two Floating Storage and Offloading Vessels [Member]
Segment Reporting Information [Line Items]
Number of Vessels Operated by Joint Venture | property	2
International Crude Tankers Segment [Member] | Time Charter Equivalent Services [Member]
Segment Reporting Information [Line Items]
Revenues, services	$ 36,475
International Product Carriers Segment [Member]
Segment Reporting Information [Line Items]
Revenues, services	61,872	9,246
Time charter equivalent revenues		9,219
Depreciation and amortization	11,841	3,728
Loss/(gain) on disposal of vessels and other assets, including impairments	(3,219)	0
Adjusted income/(loss) from vessel operations	9,198	(2,673)
Equity in income/(loss) of affiliated companies	0	0
Investments in and advances to affiliated companies	23,063	7,409
Adjusted total assets	803,077	255,220
Expenditures for vessels and vessel improvements	23,381	615
Payments for drydocking	9,910	5,506
International Product Carriers Segment [Member] | Time Charter Equivalent Services [Member]
Segment Reporting Information [Line Items]
Revenues, services	61,500
Other Segments [Member]
Segment Reporting Information [Line Items]
Revenues, services	0	0
Time charter equivalent revenues		0
Depreciation and amortization	7	23
Loss/(gain) on disposal of vessels and other assets, including impairments	0	0
Adjusted income/(loss) from vessel operations	(7)	(23)
Equity in income/(loss) of affiliated companies	0	0
Investments in and advances to affiliated companies	0	0
Adjusted total assets	0	0
Expenditures for vessels and vessel improvements	0	0
Payments for drydocking	0	$ 0
Other Segments [Member] | Time Charter Equivalent Services [Member]
Segment Reporting Information [Line Items]
Revenues, services	$ 0

BUSINESS AND SEGMENT REPORTIN_3

BUSINESS AND SEGMENT REPORTING (Reconciliation of Time Charter Revenue to Shipping Revenues) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Time charter equivalent revenues	$ 97,975	$ 45,169
Add: Voyage expenses	3,507	1,587
Revenue, non lease	101,482	$ 46,756
Time Charter Equivalent Services [Member]
Revenue, non lease	$ 97,975

BUSINESS AND SEGMENT REPORTIN_4

BUSINESS AND SEGMENT REPORTING (Reconciliation of Income/(Loss) from Vessel Operations to Loss Before Reorganization) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Total adjusted income/(loss) from vessel operations of all segments	$ 3,349	$ (3,653)
General and administrative expenses	(10,166)	(8,181)
Reversal of expected credit losses	4
Third-party debt modification fees	(187)	0
Gain/(loss) on disposal of vessels and other assets, including impairments	1,376	(11)
Consolidated loss from vessel operations	(5,628)	(11,845)
Equity in income of affiliated companies	5,597	5,468
Other expense	(226)	292
Interest expense	(12,740)	(7,280)
Loss before income taxes	(12,997)	(13,365)
Vessel Operations [Member]
Total adjusted income/(loss) from vessel operations of all segments	3,349	(3,653)
General and administrative expenses	(10,166)	(8,181)
Third-party debt modification fees	(187)	0
Gain/(loss) on disposal of vessels and other assets, including impairments	1,376	(11)
Consolidated loss from vessel operations	(5,628)	(11,845)
Equity in income of affiliated companies	5,597	5,468
Other expense	(226)	292
Interest expense	(12,740)	(7,280)
Loss before income taxes	$ (12,997)	$ (13,365)

BUSINESS AND SEGMENT REPORTIN_5

BUSINESS AND SEGMENT REPORTING (Reconciliation of Assets of Segments to Consolidated Amounts) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021
Segment Reporting Information [Line Items]
Adjusted total assets	$ 2,268,112		$ 1,370,641
Cash and cash equivalents	74,553	$ 97,883	156,178
Restricted cash	1,051	1,100	16,223
Other unallocated amounts	22,877		9,010
Total assets	2,366,593	$ 2,346,780	1,552,052
Other Segments [Member]
Segment Reporting Information [Line Items]
Adjusted total assets	$ 0		$ 0

VESSELS (Narrative) (Details)

VESSELS (Narrative) (Details) $ in Thousands	Mar. 11, 2021USD ($)property	Apr. 30, 2022USD ($)property	Jan. 31, 2022USD ($)	Mar. 31, 2022USD ($)property	Mar. 31, 2021USD ($)	Dec. 31, 2021USD ($)
Impairment of long-lived assets held-for-use				$ 1,697	$ 0
Proceeds from disposal of vessels and other property, net				24,257	$ (11)
Payments to acquire equipment				3,000
Loss on contract termination				700
Vessels construction in progress				60,034		$ 49,291
$390 million Credit Facility
Debt instrument, face amount				390,000
BoComm Lease Financing
Remaining cost of construction of vessels				230,400
$525 Million Credit Agreement [Member]
Debt instrument, face amount				$ 525,000		525,000
Vessel/Fleet [Member]
Number of vessels in fleet | property				87
Dual Fuel LNG VLCC Under Construction [Member]
Expected construction costs	$ 290,000
Remaining cost of construction of vessels				$ 230,600
Number of vessels in construction | property	3
Interest costs capitalized				1,300		600
Leasing term of property	7 years
Vessels construction in progress				60,000		$ 49,300
Panamax 2004 And Handysize 2006 Vessel [Member]
Impairment of long-lived assets to be disposed of				1,200
Handysize 2006 Vessel [Member] | Write Down Vessel Value To Fair Value [Member]
Impairment of long-lived assets to be disposed of				500
Medium Range Vessel 2010 [Member]
Proceeds from disposal of vessels and other property, net			$ 16,500
Net gain (loss) on disposal of vessel				$ 4,600
Long Range One Vessel 2011 [Member]
Purchase agreement, purchase amount			$ 19,500
Three Vessels With Memoranda Of Sales [Member]
Number of vessels marketed to be sold | property				3
Panamax 2002 With Memoranda Of Sales [Member]
Number of vessels marketed to be sold | property				1
Panamax 2004 With Memoranda Of Sales [Member]
Number of vessels marketed to be sold | property				1
Handysize 2006 With Memoranda Of Sales [Member]
Number of vessels marketed to be sold | property				1
Subsequent Event [Member] | Three Vessels With Memoranda Of Sales [Member]
Selling Expense		$ 800
Subsequent Event [Member] | Medium Range 2008 Vessel With Memoranda Of Sales [Member]
Number of vessels marketed to be sold | property		1

EQUITY METHOD INVESTMENTS (Narr

EQUITY METHOD INVESTMENTS (Narrative) (Details) $ in Thousands	Mar. 29, 2018USD ($)	Apr. 30, 2018USD ($)	Mar. 31, 2022USD ($)contractitem	Mar. 31, 2021USD ($)	Dec. 31, 2021USD ($)
Schedule of Equity Method Investments [Line Items]
Number of joint ventures | item			2
Investments in and advances to affiliated companies			$ 183,361		$ 180,331
Proceeds from long-term lines of credit			50,000	$ 0
Minimum liquidity level, threshold amount			$ 50,000
Minimum liquidity level, threshold percentage of debt			5.00%
Other Equity Method Investments [Member]
Schedule of Equity Method Investments [Line Items]
Investments in and advances to affiliated companies			$ 38,300
FSO Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Number of contracts related to joint venture | contract			2
FSO Joint Venture [Member] | FSO Asia and FSO Africa [Member]
Schedule of Equity Method Investments [Line Items]
Investments in and advances to affiliated companies			$ 145,100
FSO Joint Venture [Member] | Two Floating Storage and Offloading Vessels [Member]
Schedule of Equity Method Investments [Line Items]
Number of contracts related to joint venture | contract			2
LNG Joint Venture, TI Africa and TI Asia Limited [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage			50.00%
FSO Term Loan [Member] | FSO Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Minimum liquidity level, threshold amount		$ 50,000
Minimum liquidity level, threshold percentage of debt		5.00%
Minimum cash, threshold amount, debt instrument covenant		$ 30,000
Guarantor obligations, maximum exposure, undiscounted			$ 13,300
Guarantor obligations, current carrying value			$ 0
Debt instrument, basis spread on variable rate			2.00%
Secured Debt | FSO Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Line of credit facility, maximum borrowing capacity	$ 220,000
Proceeds from long-term lines of credit	$ 220,000
Financial Guarantee [Member] | FSO Term Loan [Member] | FSO Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Proceeds from long-term lines of credit		$ 110,000

EQUITY METHOD INVESTMENTS (Resu

EQUITY METHOD INVESTMENTS (Results of Operations of Equity Method Investments) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Shipping revenues	$ 101,482	$ 46,756
Loss from vessel operations	(5,628)	(11,845)
Other expense	(226)	292
Interest expense	(12,740)	(7,280)
Income tax (provision)/benefit	(4)	0
Net loss attributable to the Company	(13,001)	(13,365)
Equity in income of affiliated companies	5,597	5,468
Equity Method Investments [Member]
Shipping revenues	25,887	25,846
Ship operating expenses	14,292	13,931
Loss from vessel operations	11,595	11,915
Interest expense	(543)	(1,212)
Income tax (provision)/benefit	(1,029)	(993)
Net loss attributable to the Company	$ 10,023	$ 9,710

VARIABLE INTEREST ENTITIES (V_3

VARIABLE INTEREST ENTITIES (VIEs) (Narrative) (Details) $ in Thousands	Jul. 16, 2021	Mar. 31, 2022USD ($)item	Mar. 31, 2021USD ($)	Dec. 31, 2021USD ($)
Variable Interest Entity [Line Items]
Number of joint ventures | item		2
Accounts receivable, net, current		$ 120,465		$ 107,096
Payments on debt		$ 35,284	$ 15,371
DASM [Member]
Variable Interest Entity [Line Items]
Variable interest entity percentage of ownership	51.00%
DASM [Member] | A E Holdings [Member
Variable Interest Entity [Line Items]
Variable interest entity percentage of ownership	49.00%
Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Number of commercial pools | item		6
Variable Interest Entity, Not Primary Beneficiary [Member] | FSO Joint Venture [Member]
Variable Interest Entity [Line Items]
Accounts receivable, net, current		$ 106,900

VARIABLE INTEREST ENTITIES (V_4

VARIABLE INTEREST ENTITIES (VIEs) (Balance Sheet Carrying Amounts Related to VIEs) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021
Variable Interest Entity [Line Items]
Investments in Affiliated Companies	$ 183,361	$ 144,770
Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Investments in Affiliated Companies	$ 181,960

VARIABLE INTEREST ENTITIES (V_5

VARIABLE INTEREST ENTITIES (VIEs) (Comparison of Liability to Maximum Exposure to Loss) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Variable Interest Entity [Line Items]
Other Liabilities	$ 2,023	$ 2,288
Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Maximum Exposure to Loss	$ 195,271

FAIR VALUE OF FINANCIAL INSTR_3

FAIR VALUE OF FINANCIAL INSTRUMENTS, DERIVATIVES AND FAIR VALUE DISCLOSURES (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Fair Value Of Financial Instruments Derivatives And Fair Value Disclosures [Line Items]
Long-term debt	$ 1,121,423		$ 1,104,985
Payments interest rate swap settlement	0	$ 1,312
Net change in unrealized gains/(losses) on cash flow hedges	10,762	$ 10,283
$390 Million Facility Term Loan
Fair Value Of Financial Instruments Derivatives And Fair Value Disclosures [Line Items]
Debt instrument, face amount	390,000
$390 Million Facility Term Loan | Term loan
Fair Value Of Financial Instruments Derivatives And Fair Value Disclosures [Line Items]
Debt instrument, face amount	390,000		390,000
Long-term debt	170,769		188,693
$525 Million Facility Term Loan | Term loan
Fair Value Of Financial Instruments Derivatives And Fair Value Disclosures [Line Items]
Debt instrument, face amount	525,000		525,000
Long-term debt	$ 198,265		$ 216,289

FAIR VALUE OF FINANCIAL INSTR_4

FAIR VALUE OF FINANCIAL INSTRUMENTS, DERIVATIVES AND FAIR VALUE DISCLOSURES (Other Than Derivatives) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 75,604
Restricted cash	1,051	$ 1,100	$ 16,223
$390 Million Facility Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, face amount	390,000
Term loan | $390 Million Facility Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, face amount	390,000	390,000
Term loan | $525 Million Facility Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, face amount	525,000	525,000
Term loan | $360 Million Facility Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, face amount	360,000	360,000
Revolver Facility | $525 Million Facility Revolving Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, face amount	525,000	525,000
Revolver Facility | $360 Million Facility Revolving Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, face amount	$ 360,000	$ 360,000
Senior Notes | 8.5% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, interest rate, stated percentage	8.50%	8.50%
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents		$ 98,933
Fair Value, Inputs, Level 1 [Member] | Senior Notes | 8.5% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes Payable, Fair Value Disclosure	$ (25,833)	(25,940)
Fair Value, Inputs, Level 2 [Member] | $390 Million Facility Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans Payable, Fair Value Disclosure	(172,766)	(191,050)
Fair Value, Inputs, Level 2 [Member] | $525 Million Facility Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans Payable, Fair Value Disclosure	(198,265)	(216,289)
Fair Value, Inputs, Level 2 [Member] | $525 Million Facility Revolving Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans Payable, Fair Value Disclosure	(94,193)	(44,193)
Fair Value, Inputs, Level 2 [Member] | $360 Million Facility Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans Payable, Fair Value Disclosure	(96,413)	(105,325)
Fair Value, Inputs, Level 2 [Member] | $360 Million Facility Revolving Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans Payable, Fair Value Disclosure	(38,889)	(38,889)
Fair Value, Inputs, Level 2 [Member] | Macquarie Credit Facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans Payable, Fair Value Disclosure	(18,950)	(19,475)
Fair Value, Inputs, Level 2 [Member] | ING Credit Facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans Payable, Fair Value Disclosure	(24,479)	(25,000)
Fair Value, Inputs, Level 2 [Member] | Ocean Yield Lease Financing
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Lease financing, Fair Value Disclosure	(363,105)	(370,305)
Fair Value, Inputs, Level 2 [Member] | BoComm Lease Financing
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Lease financing, Fair Value Disclosure	(14,411)	(9,608)
Fair Value, Inputs, Level 2 [Member] | Toshin Lease Financing
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Lease financing, Fair Value Disclosure	(16,677)	(16,995)
Fair Value, Inputs, Level 2 [Member] | COSCO Lease Financing
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Lease financing, Fair Value Disclosure	(51,493)	$ (52,746)
Fair Value, Inputs, Level 2 [Member] | Hyuga Lease Financing
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Lease financing, Fair Value Disclosure	$ (16,386)

FAIR VALUE OF FINANCIAL INSTR_5

FAIR VALUE OF FINANCIAL INSTRUMENTS, DERIVATIVES AND FAIR VALUE DISCLOSURES (Fair Value of Derivative Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current Portion of Derivative Assets [Member]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	$ 2,061
Non Current Portion of Derivative Assets [Member]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	5,959	$ 1,296
Current Portion of Derivative Liabilities [Member]
Derivative Instruments in Hedges, Liabilities, at Fair Value	0	(2,539)
Non Current Portion of Derivative Liabilities [Member]
Derivative Instruments in Hedges, Liabilities, at Fair Value	0	(757)
Designated as Hedging Instrument [Member] | Current Portion of Derivative Assets [Member] | Interest Rate Swap [Member]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	2,061
Designated as Hedging Instrument [Member] | Non Current Portion of Derivative Assets [Member] | Interest Rate Swap [Member]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	5,959	1,296
Designated as Hedging Instrument [Member] | Current Portion of Derivative Liabilities [Member] | Interest Rate Swap [Member]
Derivative Instruments in Hedges, Liabilities, at Fair Value	0	(2,539)
Designated as Hedging Instrument [Member] | Non Current Portion of Derivative Liabilities [Member] | Interest Rate Swap [Member]
Derivative Instruments in Hedges, Liabilities, at Fair Value	$ 0	$ (757)

FAIR VALUE OF FINANCIAL INSTR_6

FAIR VALUE OF FINANCIAL INSTRUMENTS, DERIVATIVES AND FAIR VALUE DISCLOSURES (Effect of Cash Flow Hedging Relationships) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Designated as Hedging Instrument [Member]
Total other comprehensive loss	$ 9,058	$ 7,281
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Total other comprehensive loss	$ 9,058	7,747
Hybrid Instrument [Member] | Interest Rate Swap [Member]
Total other comprehensive loss		$ (466)

FAIR VALUE OF FINANCIAL INSTR_7

FAIR VALUE OF FINANCIAL INSTRUMENTS, DERIVATIVES AND FAIR VALUE DISCLOSURES (Effect of Cash Flow Hedging Relationships on Consolidated Statements of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Effective portion of gain/(loss) reclassified from accumulated other comprehensive loss	$ 1,704	$ 3,002
Interest Expense [Member]
Effective portion of gain/(loss) reclassified from accumulated other comprehensive loss	1,574	2,708
Not Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Effective portion of gain/(loss) reclassified from accumulated other comprehensive loss	582	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Effective portion of gain/(loss) reclassified from accumulated other comprehensive loss	992	1,115
Hybrid Instrument [Member] | Interest Rate Swap [Member]
Effective portion of gain/(loss) reclassified from accumulated other comprehensive loss	$ 0	$ 1,593

FAIR VALUE OF FINANCIAL INSTR_8

FAIR VALUE OF FINANCIAL INSTRUMENTS, DERIVATIVES AND FAIR VALUE DISCLOSURES (Fair Values of Assets and Liabilities Measured on Recurring Basis) (Details) - Interest Rate Swap [Member] - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Derivative Asset	$ 8,020	$ 1,296
Derivative liability	$ 0	$ (3,296)

FAIR VALUE OF FINANCIAL INSTR_9

FAIR VALUE OF FINANCIAL INSTRUMENTS, DERIVATIVES AND FAIR VALUE DISCLOSURES (Fair Value of Items Measured on Nonrecurring Basis) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)property
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale and property, plant and equipment fair value disclosure	$ 27,000
International Crude Tankers Segment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale, fair value disclosure	7,561
Impairment	$ (1,019)
Number of vessels with impairment triggering events | property	1
International Crude Tankers Segment [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale, fair value disclosure	$ 7,561
International Product Carriers Segment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Property, plant and equipment, fair value	9,575
Assets held for sale, fair value disclosure	9,850
Vessels held for use, Impairment Charges	(471)
Impairment	(207)
International Product Carriers Segment [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Property, plant and equipment, fair value	9,575
Assets held for sale, fair value disclosure	9,850
Write Down Vessel Value To Fair Value [Member] | International Crude Tankers Segment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment	(900)
Estimated Costs To Sell Vessel [Member] | International Crude Tankers Segment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment	(100)
Estimated Costs To Sell Vessel [Member] | International Product Carriers Segment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment	$ (200)

DEBT (Schedule of Long-term Deb

DEBT (Schedule of Long-term Debt Instruments) (Details) - USD ($) $ in Thousands	Mar. 04, 2022	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Debt
Long-term debt		$ 1,121,423		$ 1,104,985
Less current portion		(178,391)		(178,715)
Long-term portion		943,032		926,270
Borrowings on revolving credit facilities		50,000	$ 0
$390 Million Facility Term Loan
Debt
Debt instrument, face amount		390,000
Macquarie Credit Facility
Debt
Long-term debt		18,244		18,720
Unamortized discount and deferred finance costs		706		755
ING Credit Facility
Debt
Long-term debt		23,966		24,454
Unamortized discount and deferred finance costs		513		546
Ocean Yield Lease Financing
Debt
Long-term debt		359,474		366,506
Unamortized discount and deferred finance costs		3,632		3,799
BoComm Lease Financing
Debt
Long-term debt		14,261		9,494
Unamortized discount and deferred finance costs		150		114
Toshin Lease Financing
Debt
Long-term debt		16,260		16,567
Unamortized discount and deferred finance costs		417		428
COSCO Lease Financing
Debt
Long-term debt		50,118		51,393
Unamortized discount and deferred finance costs		1,375		1,353
Hyuga Lease Financing
Debt
Long-term debt		16,025		0
Unamortized discount and deferred finance costs		361
Term loan | $390 Million Facility Term Loan
Debt
Long-term debt		170,769		188,693
Debt instrument, face amount		390,000		390,000
Unamortized discount and deferred finance costs		1,997		2,357
Term loan | $525 Million Facility Term Loan
Debt
Long-term debt		198,265		216,289
Debt instrument, face amount		525,000		525,000
Term loan | $360 Million Facility Term Loan
Debt
Long-term debt		96,413		105,325
Debt instrument, face amount		360,000		360,000
Revolver Facility | 390 Million Facility Revolving Loan
Debt
Debt instrument, face amount		390,000
Available amount under revolving facility		40,000
Revolver Facility | $525 Million Facility Revolving Loan
Debt
Long-term debt		94,193		44,193
Debt instrument, face amount		525,000		525,000
Borrowings on revolving credit facilities	$ 50,000
Available amount under revolving facility		50,000
Revolver Facility | $360 Million Facility Revolving Loan
Debt
Long-term debt		38,889		38,889
Debt instrument, face amount		360,000		360,000
Available amount under revolving facility		0
Senior Notes | 8.5% Senior Notes
Debt
Long-term debt		24,546		24,462
Unamortized discount and deferred finance costs		$ 454		$ 538
Debt instrument, interest rate, stated percentage		8.50%		8.50%

DEBT - Hyuga Lease Financing (D

DEBT - Hyuga Lease Financing (Details) - USD ($) $ in Thousands	Jan. 14, 2022	Mar. 31, 2022
Hyuga Lease Financing
Debt
Lease term of sale leaseback transaction	9 years
Sale Leaseback Transaction, purchase obligation	$ 1,500
Hyuga Lease Financing | First three years
Debt
Bareboat charter rate	6,300
Hyuga Lease Financing | Second three years
Debt
Bareboat charter rate	6,200
Hyuga Lease Financing | Last three years
Debt
Bareboat charter rate	6,000
Hyuga Lease Financing | 2011-built MR
Debt
Sale Leaseback Transaction, Net Sale Price	16,700
Sale Leaseback Transaction, Proceeds	5,700
$390 Million Facility Term Loan
Debt
Repayments of secured debt		$ 11,000
$390 Million Facility Term Loan | 2011-built MR
Debt
Maximum borrowing capacity	390,000
Repayments of secured debt	$ 11,000

DEBT - Kaiyo Lease Financing (D

DEBT - Kaiyo Lease Financing (Details) $ in Thousands	Apr. 25, 2022USD ($)	Mar. 31, 2022USD ($)	Apr. 01, 2022USD ($)item
Kaiyo Lease Financing
Debt
Lease term of sale leaseback transaction	8 years
Sale Leaseback Transaction, purchase obligation	$ 1,500
Kaiyo Lease Financing | First four years
Debt
Bareboat charter rate	6,250
Kaiyo Lease Financing | Remaining four years
Debt
Bareboat charter rate	6,150
Kaiyo Lease Financing | 2010-built MR
Debt
Sale Leaseback Transaction, Net Sale Price	15,200
Sale Leaseback Transaction, Proceeds	5,400
$390 Million Facility Term Loan
Debt
Repayments of secured debt		$ 11,000
Number of vessels in lease financing arrangement | item			9
Future quarterly principal amortization of debt		$ 7,300	$ 6,900
$390 Million Facility Term Loan | 2010-built MR
Debt
Maximum borrowing capacity	390,000
Repayments of secured debt	$ 9,800

DEBT (Debt Covenants) (Narrativ

DEBT (Debt Covenants) (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Debt
Debt instrument, covenant compliance	The Company was in compliance with the financial and non-financial covenants under all of its financing arrangements as of March 31, 2022.
Minimum liquidity level, threshold amount	$ 50
Minimum liquidity level, threshold percentage of debt	5.00%
Threshold leverage ratio	0.60%
Core Term Loan Facility and Core Revolving Facility
Debt
Debt Instrument Covenant, Fair Market Value of the Core Collateral Vessels, Threshold Percentage Of Outstanding Principal Amount	135.00%
$390 million Credit Facility
Debt
Debt instrument, face amount	$ 390
$525 Million Credit Agreement [Member]
Debt
Debt instrument, face amount	525	$ 525
$360 Million Credit Agreement [Member]
Debt
Debt instrument, face amount	360
$390 Million Facility Term Loan
Debt
Debt instrument, face amount	$ 390
Senior Notes | 8.5% Senior Notes
Debt
Debt instrument covenant limitation on total borrowings percentage of total assets	70.00%
Debt instrument covenant net worth	$ 600
Debt instrument, interest rate, stated percentage	8.50%	8.50%

DEBT (Interest Expense, Debt Mo

DEBT (Interest Expense, Debt Modification, Repurchases and Extinguishment) (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Debt
Interest Expense	$ 13.3	$ 7.2
Interest paid, net	11.8	$ 6.3
Gains (losses) on repurchase and extinguishment of debt	(0.1)
$390 million Credit Facility
Debt
Debt instrument, face amount	390
$390 Million Facility Term Loan
Debt
Debt instrument, face amount	390
Write off of deferred debt issuance cost	0.1
Repayments of secured debt	$ 11

TAXES (Narrative) (Details)

TAXES (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
TAXES [Abstract]
Income tax expense (benefit)	$ 4	$ 0

CAPITAL STOCK AND STOCK COMPE_2

CAPITAL STOCK AND STOCK COMPENSATION (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	Mar. 28, 2022	Jul. 16, 2021	Feb. 23, 2021	Apr. 30, 2022	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Jul. 28, 2021	Jul. 15, 2021	Jun. 04, 2021	Aug. 04, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, authorized amount											$ 50,000
Dividends payable, date declared			Feb. 28, 2022
Dividends payable, amount per share			$ 0.06					$ 0.06		$ 0.06
Payments of dividends	$ 3,000				$ 2,980	$ 1,681
Dividends payable, date of record			Mar. 14, 2022
Dividends payable, date to be paid			Mar. 28, 2022
Common stock, shares, issued		50,674,393			49,641,506		49,612,019
Common stock, shares, outstanding		50,674,393			49,641,506		49,612,019
Special dividends that can be paid prior to the effective date under the business combination									$ 31,500
Stock Repurchase Program, Remaining Authorized Repurchase Amount					$ 33,300
Treasury Stock, Shares, Acquired					0	0
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares paid for tax withholding for share based compensation					57,726	22,830
Shares paid for tax withholding for share based compensation, per share amount					$ 16.81	$ 21.42
Number of shares convertible into common shares per equity award represents					1
Restricted Stock Units (RSUs) [Member] | Certain Employees and Senior Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted					124,590
Restricted Stock Units (RSUs) [Member] | Certain Employees and Senior Officers [Member] | Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted				328,554
Granted, per share				$ 19.63
Share-based Compensation Award, Tranche One [Member] | Restricted Stock Units (RSUs) [Member] | Certain Employees and Senior Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, per share					$ 19.63
Vesting percentage					50.00%
Return on investment capital performance period					3 years
Share-based Compensation Award, Tranche One [Member] | Restricted Stock Units (RSUs) [Member] | Certain Employees and Senior Officers [Member] | Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted				304,650
Share-based Payment Arrangement, Tranche Two [Member] | Restricted Stock Units (RSUs) [Member] | Certain Employees and Senior Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, per share					$ 20.65
Vesting percentage					1.00%
Total shareholder return performance period					3 years
Share-based Payment Arrangement, Tranche Two [Member] | Restricted Stock Units (RSUs) [Member] | Certain Employees and Senior Officers [Member] | Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted				23,904
Share-based Payment Arrangement, Tranche Three [Member] | Restricted Stock Units (RSUs) [Member] | Certain Employees and Senior Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shareholder return peer group performance period					3 years
Diamond S Shareholders
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of outstanding shares		44.25%
Pre Merger International Seaways Shareholders [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of outstanding shares		55.75%

ACCUMULATED OTHER COMPREHENSI_3

ACCUMULATED OTHER COMPREHENSIVE LOSS (Narrative) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)
ACCUMULATED OTHER COMPREHENSIVE LOSS [Abstract]
Derivative instruments, gain (loss) reclassification from accumulated oci to income, estimated net amount to be transferred	$ 12

ACCUMULATED OTHER COMPREHENSI_4

ACCUMULATED OTHER COMPREHENSIVE LOSS (Components of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
ACCUMULATED OTHER COMPREHENSIVE LOSS [Abstract]
Unrealized losses on derivative instruments	$ 5,899	$ (4,863)
Items not yet recognized as a component of net periodic benefit cost (pension plans)	(7,300)	(7,497)
Accumulated other comprehensive loss	$ (1,401)	$ (12,360)

ACCUMULATED OTHER COMPREHENSI_5

ACCUMULATED OTHER COMPREHENSIVE LOSS (Changes in Components of AOCI, Net of Related Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Balance, beginning	$ 1,169,748
Other Comprehensive income, net of tax	10,959	$ 10,219
Balance, ending	1,164,866
Accumulated Other Comprehensive Loss [Member]
Balance, beginning	(12,360)	(32,613)
Current period change, excluding amounts reclassified from accumulated other comprehensive loss	9,255	7,217
Amounts reclassified from accumulated other comprehensive loss	1,704	3,002
Other Comprehensive income, net of tax	10,959	10,219
Balance, ending	(1,401)	(22,394)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Balance, beginning	(4,863)	(24,098)
Current period change, excluding amounts reclassified from accumulated other comprehensive loss	9,058	7,281
Amounts reclassified from accumulated other comprehensive loss	1,704	3,002
Balance, ending	5,899	(13,815)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance, beginning	(7,497)	(8,515)
Current period change, excluding amounts reclassified from accumulated other comprehensive loss	197	(64)
Amounts reclassified from accumulated other comprehensive loss	0	0
Balance, ending	$ (7,300)	$ (8,579)

ACCUMULATED OTHER COMPREHENSI_6

ACCUMULATED OTHER COMPREHENSIVE LOSS (Amounts Reclassified out of AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Unrealized losses on available-for-sale securities:
Equity in income of affiliated companies	$ (12,997)	$ (13,365)
Income (loss) from equity method investments	5,597	5,468
Interest expense	12,740	7,280
Other income	(226)	292
Total reclassified out of AOCL, before tax	1,704	3,002
Interest Rate Cap [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Unrealized losses on available-for-sale securities:
Interest expense	582	0
Interest Rate Swap [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Unrealized losses on available-for-sale securities:
Equity in income of affiliated companies	130	294
Interest expense	992	1,115
Hybrid Instrument [Member] | Interest Rate Swap [Member]
Unrealized losses on available-for-sale securities:
Total reclassified out of AOCL, before tax	0	1,593
Hybrid Instrument [Member] | Interest Rate Swap [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Unrealized losses on available-for-sale securities:
Interest expense	$ 0	$ 1,593

REVENUE (Narrative) (Details)

REVENUE (Narrative) (Details)	3 Months Ended
	Mar. 31, 2022USD ($)property	Mar. 31, 2021USD ($)
Revenues, Total | $	$ 101,482,000	$ 46,756,000
Contract with customer, performance obligation satisfied in previous period | $	0	$ 0
Capitalized contract cost, gross | $	$ 0
Lease cancellation period notice	90 days
Very Large Crude Carrier [Member]
Number of vessels party to contracts	1
LR2 Vessel [Member]
Number of vessels party to contracts	1
Aframaxes (LR2) [Member]
Number of vessels party to contracts	1
MR Vessel [Member]
Number of vessels party to contracts	1

REVENUE (Schedule of Disaggrega

REVENUE (Schedule of Disaggregated Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Revenue, non lease	$ 101,482	$ 46,756
Shipping revenues	101,482	46,756
Loss of hire proceeds		500
International Crude Tankers Segment [Member]
Revenue, non lease	39,610	37,510
Shipping revenues	39,610	37,510
International Product Carriers Segment [Member]
Revenue, non lease	61,872	9,246
Shipping revenues	61,872	9,246
Other Segments [Member]
Revenue, non lease	0	0
Pool Revenue Leases [Member]
Shipping revenues	83,762	24,659
Pool Revenue Leases [Member] | Fixed-Price Contract [Member]
Revenue, operating leases	83,762	24,659
Pool Revenue Leases [Member] | International Crude Tankers Segment [Member] | Fixed-Price Contract [Member]
Revenue, operating leases	27,310	17,658
Pool Revenue Leases [Member] | International Product Carriers Segment [Member] | Fixed-Price Contract [Member]
Revenue, operating leases	56,452	7,001
Voyage Charter Leases Non Variable Payments [Member] | Fixed-Price Contract [Member]
Revenue, lease non-variable	5,891	1,514
Voyage Charter Leases Non Variable Payments [Member] | International Crude Tankers Segment [Member] | Fixed-Price Contract [Member]
Revenue, lease non-variable	2,844	940
Voyage Charter Leases Non Variable Payments [Member] | International Product Carriers Segment [Member] | Fixed-Price Contract [Member]
Revenue, lease non-variable	3,047	574
Voyage Charter Leases Variable Payments [Member] | Fixed-Price Contract [Member]
Revenue, operating leases		51
Revenue (expense), operating leases	(64)
Voyage Charter Leases Variable Payments [Member] | International Crude Tankers Segment [Member] | Fixed-Price Contract [Member]
Revenue (expense), operating leases	14
Voyage Charter Leases Variable Payments [Member] | International Product Carriers Segment [Member] | Fixed-Price Contract [Member]
Revenue, operating leases		51
Revenue (expense), operating leases	(78)
Time and Bareboat Charter Leases [Member]
Shipping revenues	6,175	14,698
Time and Bareboat Charter Leases [Member] | Fixed-Price Contract [Member]
Revenue, operating leases	6,175	14,698
Time and Bareboat Charter Leases [Member] | International Crude Tankers Segment [Member] | Fixed-Price Contract [Member]
Revenue, operating leases	3,724	13,078
Time and Bareboat Charter Leases [Member] | International Product Carriers Segment [Member] | Fixed-Price Contract [Member]
Revenue, operating leases	2,451	1,620
Voyage Charter Leases [Member]
Shipping revenues	11,545	7,399
Voyage Charter Leases [Member] | Lightering Services Component [Member]
Revenue, non lease	5,718	5,834
Voyage Charter Leases [Member] | International Crude Tankers Segment [Member] | Lightering Services Component [Member]
Revenue, non lease	$ 5,718	$ 5,834

REVENUE (Schedule of Contract R

REVENUE (Schedule of Contract Related Receivables, Assets and Liabilities with Customers) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
REVENUE [Abstract]
Voyage receivables - receivables	$ 2,018	$ 2,306
Contract asset (voyage receivables unbilled receivables)	185	225
Contract liability (deferred revenues)	$ 0	$ 0

LEASES (Narrative) (Details)

LEASES (Narrative) (Details)	3 Months Ended
	Mar. 31, 2022propertylease
Leases [Line Items]
Number of major categories of leases | lease	2
MR Vessel [Member]
Leases [Line Items]
Number of vessels chartered	1
Aframaxes (LR2) [Member]
Leases [Line Items]
Vessels that have commitments to charter	2
LR2 Vessel [Member]
Leases [Line Items]
Number of vessels chartered	1
Very Large Crude Carrier [Member]
Leases [Line Items]
Number of vessels chartered	1
Suezmax
Leases [Line Items]
Number of vessels chartered	1
Bareboat Charters-In [Member] | Aframaxes (LR2) [Member]
Leases [Line Items]
Number of vessels chartered	2
Time Charters-In [Member] | LR1 Vessel [Member]
Leases [Line Items]
Vessels that have commitments to charter	2
Maximum
Leases [Line Items]
Excluded vessels chartered period	1 month

LEASES (Schedule of lease cost)

LEASES (Schedule of lease cost) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating lease, cost	$ 7,309	$ 5,741
Total lease cost	4,167	3,637
Vessel/Fleet [Member] | Charter Hire Expense [Member]
Operating lease, cost	2,418	2,421
Short-term lease, cost	1,479	901
Office Space [Member] | General and Administrative Expense [Member]
Operating lease, cost	227	273
Office Space [Member] | Voyage Expense [Member]
Operating lease, cost	43	42
Lightering Services Component [Member] | Vessel/Fleet [Member]
Short-term lease, cost	$ 400	$ 100

LEASES (Supplemental lease info

LEASES (Supplemental lease information) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows used for operating leases	$ 2,486	$ 2,736
Operating Lease, Liability, Current	10,767		$ 8,393
Operating Lease, Liability, Noncurrent	10,814		12,522
Total operating lease liabilities	(21,581)		(20,915)
Operating Lease, Right-of-Use Asset	$ 23,425		$ 23,168
Operating Lease, Weighted Average Remaining Lease Term	4 years 5 months 23 days		5 years 1 month 24 days
Operating Lease, Weighted Average Discount Rate, Percent	5.16%		5.42%

LEASES (Bareboat and Time Chart

LEASES (Bareboat and Time Charters-In) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Leases [Line Items]
Total operating lease liabilities	$ 21,581	$ 20,915
Bareboat Charters-In [Member]
Leases [Line Items]
2022	4,730
2023	4,532
Total lease payments	9,262
less imputed interest	(494)
Total operating lease liabilities	$ 8,768
2022, operating days	550 days
2023, operating days	556 days
Operating days, total	1106 days
Time Charters-In [Member]
Leases [Line Items]
2022	$ 3,592
2023	1,381
Total lease payments	4,973
less imputed interest	(56)
Total operating lease liabilities	$ 4,917
2022, operating days	550 days
2023, operating days	210 days
Operating days, total	760 days

LEASES (Future Minimum Lease Ob

LEASES (Future Minimum Lease Obligations for Office Space) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Leases [Line Items]
Total operating lease liabilities	$ 21,581	$ 20,915
Office Space And Lightering Workboat Dock Space [Member]
Leases [Line Items]
2022	205
2023	229
2024	973
2025	998
2026	1,024
Thereafter	6,907
Total lease payments	10,336
less imputed interest	(2,440)
Total operating lease liabilities	$ 7,896

LEASES (Future Minimum Revenues

LEASES (Future Minimum Revenues on Charters-Out) (Details) - Charters-Out [Member] $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)
Operating Leases, Future Minimum Payments Receivable [Abstract]
2022	$ 19,304
2023	3,240
Net minimum lease payments	$ 22,544
2022, revenue days	1079 days
2023, revenue days	72 days
Revenue Days	675 days

CONTINGENCIES (Narrative) (Deta

CONTINGENCIES (Narrative) (Details)	3 Months Ended
	Mar. 31, 2022
Merchant Navy Ratings Pension Fund [Member]
Loss Contingencies [Line Items]
Multiemployer period of performance in the past	20 years