XML 72 R38.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Variable Interest Entities - Investment Products (Details) | 9 Months Ended
--- | ---
Sep. 30, 2014
Variable Interest Entities - Investment Products [Abstract] |
Percentage not approached by expected return on any VIE investment | 50.00%

X
- Definition Variable Interest Entities, Investment Objective Threshold Percentage + References No definition available. + Details
Name: | seic_VariableInterestEntitiesInvestmentObjectiveThresholdPercentage
Namespace Prefix: | seic_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | seic_VariableInterestEntitiesInvestmentProductsAbstract
Namespace Prefix: | seic_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration