Derivative Financial Instruments (Fair Value And Related Number Of Derivative Contracts Categorized By Predominant Risk Exposure) (Details) $ in Thousands	Sep. 30, 2017 USD ($) Contract	Dec. 31, 2016 USD ($) Contract
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 2,784,013	$ 4,627,076
Fair Value, Liabilities	3,290,194	4,880,022
Counterparty/cash-collateral netting, Assets	(2,595,355)	(4,255,998)
Counterparty/cash-collateral netting, Liabilities	(2,714,115)	(4,229,213)
Net Amounts in Consolidated Statements of Financial Condition	188,658	371,078
Net Amounts in Consolidated Statements of Financial Condition	576,079	650,809
Designated as Accounting Hedges [Member] \| Interest Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 11,654
Number of Contracts, Assets \| Contract	1
Fair Value, Liabilities	$ 0
Number of Contracts, Liabilities \| Contract	0
Not Designated as Accounting Hedges [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 2,772,359	4,627,076
Fair Value, Liabilities	3,290,194	4,880,022
Counterparty/cash-collateral netting, Assets	(2,595,355)	(4,255,998)
Counterparty/cash-collateral netting, Liabilities	(2,714,115)	(4,229,213)
Net Amounts in Consolidated Statements of Financial Condition	177,004	371,078
Net Amounts in Consolidated Statements of Financial Condition	576,079	650,809
Not Designated as Accounting Hedges [Member] \| Interest Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 1,777,254	$ 3,282,245
Number of Contracts, Assets \| Contract	17,997	29,032
Fair Value, Liabilities	$ 1,698,297	$ 3,159,457
Number of Contracts, Liabilities \| Contract	42,934	34,845
Not Designated as Accounting Hedges [Member] \| Foreign Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 370,203	$ 529,669
Number of Contracts, Assets \| Contract	5,690	7,826
Fair Value, Liabilities	$ 369,971	$ 516,869
Number of Contracts, Liabilities \| Contract	6,733	8,319
Not Designated as Accounting Hedges [Member] \| Equity Contracts [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 549,030	$ 786,987
Number of Contracts, Assets \| Contract	2,199,786	2,843,329
Fair Value, Liabilities	$ 1,127,705	$ 1,169,201
Number of Contracts, Liabilities \| Contract	1,849,003	2,414,715
Not Designated as Accounting Hedges [Member] \| Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 5	$ 1,906
Number of Contracts, Assets \| Contract	3,673	2,766
Fair Value, Liabilities	$ 3,543	$ 6,430
Number of Contracts, Liabilities \| Contract	8,727	7,289
Not Designated as Accounting Hedges [Member] \| Credit Contracts [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 75,867	$ 26,269
Number of Contracts, Assets \| Contract	303	311
Fair Value, Liabilities	$ 90,678	$ 28,065
Number of Contracts, Liabilities \| Contract	389	20,084

Derivative, Fair Value of Derivative Asset, Amount Netting in Consolidated Statement of Financial Condition

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- Definition

Derivative, Fair Value of Derivative Liability, Amount Netting in Consolidated Statement of Financial Condition

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- Definition

The number of derivative instruments of a particular derivative asset or group of derivative assets held by the entity.

+ References

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-Publisher FASB
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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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The number of derivative instruments of a particular derivative liability or group of derivative liabilities held by the entity.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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