Offsetting Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Jun. 28, 2013	Dec. 31, 2012
Schedule of Partnership's assets subject to master netting arrangements
Securities purchased under agreements to resell, Gross Amounts of Recognized Assets	$ 759,843	$ 1,092,586
Securities purchased under agreements to resell, Gross amounts offset in the Consolidated Statements of Financial Condition
Securities purchased under agreements to resell, Net amounts presented in the Consolidated Statements of Financial Condition	759,843	1,092,586
Securities purchased under agreements to resell, gross amounts not offset, financial instruments
Securities purchased under agreements to resell, gross amounts not offset, securities collateral	(759,843)	(1,092,586)
Securities purchased under agreements to resell, Net amount	$ 0	$ 0