Derivative Assets And Collateral Received (Details) (USD $)	Sep. 30, 2013		Dec. 31, 2012	Sep. 30, 2012
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Gross amounts of recognized assets	$ 215,116,000		$ 292,472,000	$ 334,025,000
Subject to Master Netting Agreements
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Gross amounts of recognized assets	198,238,000	[1]		319,702,000	[1]
Gross amounts offset in the Statement of Condition	0			0
Net amounts of assets presented in the Statement of Condition	198,238,000	[1],[2]		319,702,000	[1],[2]
Derivative liabilities available for offset	(36,770,000)			(20,218,000)
Collateral Received	(161,468,000)			(273,730,000)
Net amount	0			25,754,000
Interest Rate Contract [Member]
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Derivative Assets not subject to master netting agreements	16,900,000			14,300,000
Interest Rate Contract [Member] | Subject to Master Netting Agreements
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Gross amounts of recognized assets				319,200,000
Net amounts of assets presented in the Statement of Condition				319,200,000
Forwards And Futures [Member] | Subject to Master Netting Agreements
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Gross amounts of recognized assets				500,000
Net amounts of assets presented in the Statement of Condition				$ 500,000

[1] 2013 is comprised entirely of interest rate derivative contracts. 2012 includes $319.2 million of interest rate derivative contracts and $.5 million of forwards and futures contracts.

[2] Included in Derivative Assets on the Consolidated Condensed Statements of Condition. As of September 30, 2013 and 2012, $16.9 million and $14.3 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.