v2.4.0.8
Financial Assets And Financial Liabilities (Narrative) (Details) (USD $)
 6 Months Ended
Jun. 30, 2014
Jun. 30, 2013
Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Transfers of financial instruments owned from level 1 to level 2 $ 700,000 $ 1,900,000  
Transfers of financial instruments owned from level 2 to level 1 1,500,000 1,600,000  
Transfers of financial instruments sold, but not yet purchased from level 1 to level 2 1,400,000 800,000  
Transfers of financial instruments sold, but not yet purchased from level 2 to level 1 4,500,000 900,000  
Total financial assets, at fair value 6,700,933,000   5,879,610,000
Financial instruments sold but not yet purchased, at fair value 2,630,785,000   3,153,673,000
Level 3
      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Total financial assets, at fair value 366,000 0 158,000
Financial instruments sold but not yet purchased, at fair value $ 77,000 $ 0 $ 3,000