Contingent liabilities and commitments - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]
Guarantee of indebtedness, relating to lease deposits	$ 0.2
Guarantee of indebtedness, relating to unused letters of credit	$ 5.3

Contingent liabilities for guarantees of consolidated subsidiaries, unused letters of credit.

No definition available.

Name:	stc_ContingentLiabilitiesForGuaranteesOfConsolidatedSubsidiariesUnusedLettersofCredit
Namespace Prefix:	stc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant