Interim financial statements - Additional Information (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]
Percentage of voting rights owned in electing directors	50.00%
Statutory reserve funds, investments	$ 474,222	$ 438,511
Statutory Reserve
Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]
Statutory reserve funds, cash and cash equivalents	$ 20,100	$ 57,400
Minimum \| Stewart Information Services Corporation and subsidiaries
Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]
Percentage of voting rights owned in electing directors	20.00%
Maximum \| Stewart Information Services Corporation and subsidiaries
Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]
Percentage of voting rights owned in electing directors	50.00%

Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

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Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

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