Securities Sold Under Agreements To Repurchase And Collateral Pledged By Counterparties (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Securities Sold Under Agreements To Repurchase [Abstract]
Gross amounts of recognized liabilities	$ 451,129		$ 311,760
Gross amounts offset in the statement of Condition	0		0
Net amounts of liabilities presented in the Statement of Condition	451,129	$ 338,133	311,760
Offsetting securities purchased under agreements to resell	(2,137)		(3,605)
Securities Collateral	(448,894)		(308,088)
Net amount	$ 98		$ 67