Disclosures About Offsetting Assets And Liabilities (Financial Assets And Derivative Assets That Are Subject To Offset) (Details) - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014
Offsetting [Abstract]
Gross amounts of recognized assets, Securities borrowing	[1]	$ 480,240	$ 445,542
Net amounts presented in the Statement of Financial Condition, Securities borrowing	[1]	480,240	445,542
Gross amounts not offset in the Statement of Financial Position, Collateral received, Securities borrowing	[1]	(465,058)	(431,301)
Securities borrowed, Net amount	[1]	15,182	14,241
Gross amounts of recognized assets, Reverse repurchase agreements	[2]	242,944	55,078
Net amounts presented in the Statement of Financial Condition, Securities purchased under agreements to resell	[2]	242,944	55,078
Gross amounts not offset in the Statement of Financial Position, Collateral received, Securities purchased under agreements to resell	[2]	(242,944)	(54,955)
Securities purchased under agreements to resell, Net amount	[2]		123
Gross amounts of recognized assets		723,184	500,620
Net amounts presented in the Statements of Financial Condition		723,184	500,620
Gross amounts not offset in the Statement of Financial Position, Collateral received		(708,002)	(486,256)
Net amount		$ 15,182	$ 14,364

[1] Securities borrowing transactions are included in receivables from brokers, dealers, and clearing organizations on the consolidated statements of financial condition. See Note 3 in the notes to consolidated financial statements for additional information on receivables from brokers, dealers, and clearing organizations.

[2] Collateral received includes securities received by our company from the counterparty. These securities are not included on the consolidated statements of financial condition unless there is an event of default.