Schedule I - Financial Information of the Registrant (Parent Company) - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Condensed Financial Statements, Captions [Line Items]
Dividends paid by guaranty	$ 150.0	$ 293.9
Stewart Title Guaranty Company
Condensed Financial Statements, Captions [Line Items]
Dividends paid by guaranty	150.0	293.9	$ 30.0
Unregulated Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Dividends paid by guaranty	$ 58.7	$ 2.0

This element represents disclosure of the total aggregate cash dividends paid to the entity by consolidated subsidiaries, by unconsolidated subsidiaries, and by 50 percent or less owned persons accounted for using the equity method.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(b))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e24072-122690

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration