v3.25.2

Cover - shares	6 Months Ended
Cover - shares	Jun. 30, 2025	Jul. 29, 2025
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2025
Document Transition Report	false
Entity File Number	001-02658
Entity Registrant Name	STEWART INFORMATION SERVICES CORP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	74-1677330
Entity Address, Address Line One	1360 Post Oak Blvd.,
Entity Address, Address Line Two	Suite 100
Entity Address, City or Town	Houston,
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77056
City Area Code	713
Local Phone Number	625-8100
Title of 12(b) Security	Common Stock, $1 par value per share
Trading Symbol	STC
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		27,998,523
Entity Central Index Key	0000094344
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	Q2
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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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Boolean flag that is true when the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).

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Local phone number for entity.

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Title of a 12(b) registered security.

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STEWART INFORMATION SERVICES CORP 10-Q