XML 63 R51.htm IDEA: XBRL DOCUMENT v2.4.0.6
Accumulated Comprehensive Income (Loss) (Schedule Of Accumulated Other Comprehensive Income (Loss), Net Of Tax) (Details) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Dec. 31, 2012
Accumulated other comprehensive income (loss), Foreign Currency Translation Adjustments $ (1,446)   $ 3,410
Accumulated other comprehensive income (loss), Unrealized Holding Gains (Losses) on Investments 2,729   2,829
Accumulated Other Comprehensive Income (Loss) 1,283   6,239
Total comprehensive loss, Foreign Currency Translation Adjustments (5,307) 2,703  
Total comprehensive loss, Unrealized Holding Gains (Losses) on Investments (100)    
Total other comprehensive income, net of tax (5,407) 2,674  
Total comprehensive loss attributable to noncontrolling interest, Foreign Currency Translation Adjustments 451 (483)  
Total comprehensive income attributable to noncontrolling interest, Unrealized Holding Gains (Losses) on Investments 0    
Total comprehensive loss attributable to noncontrolling interest 451    
Total comprehensive income attributable to SEI Investments Company, Foreign Currency Translation Adjustments (4,856)    
Total comprehensive (loss) attributable to SEI Investments Company, Unrealized Holding Gains (Losses) on Investments (100)    
Total comprehensive income attributable to SEI Investments Company (4,956)    
SEI Investments Company [Member]
      
Accumulated other comprehensive income (loss), Foreign Currency Translation Adjustments (1,446)   3,861
Accumulated other comprehensive income (loss), Unrealized Holding Gains (Losses) on Investments 2,729   2,829
Accumulated Other Comprehensive Income (Loss) 1,283   6,690
Noncontrolling Interest [Member]
      
Accumulated other comprehensive income (loss), Foreign Currency Translation Adjustments 0   (451)
Accumulated other comprehensive income (loss), Unrealized Holding Gains (Losses) on Investments 0   0
Accumulated Other Comprehensive Income (Loss) $ 0   $ (451)