Derivatives (Notional and Fair Values) (Details) MMBTU in Thousands, Boe in Thousands, $ in Thousands	Dec. 31, 2018 USD ($) MMBTU Boe warrant	Dec. 31, 2017 USD ($) warrant
Derivative Asset [Abstract]
Derivative assets - Fair value	$ 107,816	$ 67,077
Less: Master Netting Arrangements	(31,569)	(20,662)
Less: Cash collateral received or paid	(13,577)	(8,024)
Derivative asset, after netting	62,670	38,391
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	118,305	75,838
Less: Master Netting Arrangements	(31,569)	(20,662)
Less: Cash collateral received/paid	(6,833)	(10,680)
Derivative liability, after netting	79,903	44,496
Foreign exchange contracts
Derivative Instruments
Notional Amount		95,200
Derivative instruments designated as hedging instruments
Derivative Instruments
Notional Amount	126,056	35,811
Derivative Asset [Abstract]
Derivative assets - Fair value	0	0
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	6,477	6,770
Derivative instruments designated as hedging instruments \| Interest rate contracts
Derivative Instruments
Notional Amount	35,811	35,811
Derivative Asset [Abstract]
Derivative assets - Fair value	0	0
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	5,866	6,770
Derivative instruments designated as hedging instruments \| Foreign exchange contracts
Derivative Instruments
Notional Amount	90,245	0
Derivative Asset [Abstract]
Derivative assets - Fair value	0	0
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	611	0
Derivative instruments not designated as hedging instruments
Derivative Instruments
Notional Amount	15,222,341	10,153,108
Derivative Asset [Abstract]
Derivative assets - Fair value	107,816	67,077
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	111,828	69,068
Derivative instruments not designated as hedging instruments \| Interest rate contracts
Derivative Instruments
Notional Amount	11,695,499	9,333,860
Derivative Asset [Abstract]
Derivative assets - Fair value	69,818	59,564
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	69,267	58,890
Derivative instruments not designated as hedging instruments \| Foreign exchange contracts
Derivative Instruments
Notional Amount	3,407,522	770,215
Derivative Asset [Abstract]
Derivative assets - Fair value	21,624	5,840
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	19,329	10,170
Derivative instruments not designated as hedging instruments \| Credit contracts
Derivative Instruments
Notional Amount	119,320	49,033
Derivative Asset [Abstract]
Derivative assets - Fair value	1	1
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	164	8
Derivative instruments not designated as hedging instruments \| Equity contracts
Derivative Instruments
Notional Amount	0	0
Derivative Asset [Abstract]
Derivative assets - Fair value	1,951	1,672
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	$ 0	$ 0
Derivative instruments not designated as hedging instruments \| Equity, Public Companies
Derivative Liability [Abstract]
Number of companies that Issued the equity contracts (Issuers Portion Only) \| warrant	4	4
Derivative instruments not designated as hedging instruments \| Equity, Private Companies
Derivative Liability [Abstract]
Number of companies that Issued the equity contracts (Issuers Portion Only) \| warrant	18	12
Derivative instruments not designated as hedging instruments \| Commodity contracts
Derivative Instruments
Notional Amount	$ 0	$ 0
Derivative Asset [Abstract]
Derivative assets - Fair value	14,422	0
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	$ 23,068	$ 0
Oil
Derivative Liability [Abstract]
Derivative, nonmonetary notional amount \| Boe	2,507
Natural Gas
Derivative Liability [Abstract]
Derivative, nonmonetary notional amount \| MMBTU	14,722

Number of Companies that Issued the Warrants (Issuers Portion Only)

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Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

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Fair value of liability associated with 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.

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