Derivative Assets And Collateral Received (Details) (USD $)	Jun. 30, 2013		Dec. 31, 2012	Jun. 30, 2012
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Gross amounts of recognized assets	$ 235,759,000		$ 292,472,000	$ 340,810,000
Derivative Assets not subject to master netting agreements	26,400,000			3,800,000
Subject to Master Netting Agreements
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Gross amounts of recognized assets	209,411,000	[1]		336,999,000	[1]
Gross amounts offset in the Statement of Condition	0			0
Net amounts of assets presented in the Statement of Condition	209,411,000	[1],[2]		336,999,000	[1],[2]
Derivative liabilities available for offset	(37,505,000)			(34,481,000)
Collateral Received	(170,712,000)			(269,683,000)
Net amount	1,194,000			32,835,000
Interest Rate Contract [Member] | Subject to Master Netting Agreements
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Gross amounts of recognized assets	209,300,000			318,300,000
Net amounts of assets presented in the Statement of Condition	209,300,000			318,300,000
Forwards And Futures [Member] | Subject to Master Netting Agreements
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Gross amounts of recognized assets	100,000			18,700,000
Net amounts of assets presented in the Statement of Condition	$ 100,000			$ 18,700,000

[1] 2013 includes $209.3 million of interest rate derivative contracts and $.1 million of forwards and futures contracts. 2012 includes $318.3 million of interest rate derivative contracts and $18.7 million of forwards and futures contracts.

[2] Included in Derivative Assets on the Consolidated Condensed Statements of Condition. As of June 30, 2013 and 2012, $26.4 million and $3.8 million, respectively, of derivative assets (primarily capital markets forward contracts) have been excluded from these tables because they are generally not subject to master netting or similar agreements.