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Contingencies, Commitments and Guarantees (Contingencies - Narrative) (Details)	6 Months Ended		12 Months Ended
	Jun. 30, 2016 USD ($) Claims	Jun. 30, 2015 Claims	Dec. 31, 2015 Claims
Minimum
Loss Contingencies
Loss Contingency, Range of Possible Loss, Portion Not Accrued	$ 0
Maximum
Loss Contingencies
Loss Contingency, Range of Possible Loss, Portion Not Accrued	$ 475,000,000
Superfund Site Settlement Agreements
Loss Contingencies
Number of regulatory matters and other claims \| Claims	2
Maximum estimate of costs for environmental testing	$ 100,000
Superfund Site Settlement Agreements \| Minimum
Loss Contingencies
Damages Sought	1,000,000
Superfund Site Settlement Agreements \| Maximum
Loss Contingencies
Maximum estimate of aggregate costs to resolve matter	1,000,000
Fauley V. Metropolitan Life Insurance Company, et al \| Maximum
Loss Contingencies
Loss Contingency, Estimate of Possible Loss	23,000,000
FINRA
Loss Contingencies
Litigation Settlement, Amount	20,000,000
FINRA Customer Reimbursement
Loss Contingencies
Litigation Settlement, Amount	$ 5,000,000
Asbestos Related Claims
Loss Contingencies
Asbestos-Related Claims \| Claims	2,348	2,022	3,856