Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

No definition available.

Name:	dei_AmendmentFlag
Namespace Prefix:	dei_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration

- Definition

PCAOB issued Audit Firm Identifier

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form 10-K
-Number 249
-Section 310

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form 20-F
-Number 249
-Section 220
-Subsection f

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form 40-F
-Number 249
-Section 240
-Subsection f

Document And Entity Information - USD ($) $ in Billions	12 Months Ended
Document And Entity Information - USD ($) $ in Billions	Dec. 31, 2025	Feb. 23, 2026	Jun. 30, 2025
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2025
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 Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 1.8
Entity Common Stock, Shares Outstanding		49,427,543
Entity Central Index Key	0001679049
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2025
Amendment Flag	false
ICFR Auditor Attestation Flag	true
Auditor Name	Ernst & Young LLP
Auditor Firm ID	42
Auditor Location	New York, NY
Documents Incorporated by Reference	Portions of the registrant’s definitive proxy statement to be filed by the registrant in connection with its 2026 Annual Meeting of Shareholders are incorporated by reference in Part III
Common Stock [Member]
Title of 12(b) Security	Common Stock (no par value)
Trading Symbol	INSW
Security Exchange Name	NYSE
Rights To Purchase Common Stock [Member]
Title of 12(b) Security	Rights to Purchase Common Stock
No Trading Symbol Flag	true
Security Exchange Name	NYSE