Derivatives (Notional and Fair Values) (Details) MMBTU in Thousands, Boe in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) MMBTU Boe company	Dec. 31, 2018 USD ($) MMBTU Boe company
Derivative Asset [Abstract]
Derivative assets - Fair value	$ 330,316	$ 107,816
Less: Master Netting Arrangements	(121,561)	(31,569)
Less: Cash collateral received or paid	(3,758)	(13,577)
Derivative asset, net	204,997	62,670
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	256,528	118,305
Less: Master Netting Arrangements	(121,561)	(31,569)
Less: Cash collateral received/paid	(38,238)	(6,833)
Derivative liability, net	$ 96,729	$ 79,903
Customer Counterparty \| Crude Oil
Derivative Liability [Abstract]
Derivative, nonmonetary notional amount, energy measure \| Boe	7,811	2,507
Customer Counterparty \| Natural Gas
Derivative Liability [Abstract]
Derivative, nonmonetary notional amount, energy measure \| MMBTU	63,773	14,722
Derivative instruments designated as hedging instruments
Derivative Instruments
Notional Amount	$ 117,193	$ 126,056
Derivative Asset [Abstract]
Derivative assets - Fair value	0	0
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	4,784	6,477
Derivative instruments designated as hedging instruments \| Interest rate contracts
Derivative Instruments
Notional Amount	31,026	35,811
Derivative Asset [Abstract]
Derivative assets - Fair value	0	0
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	3,198	5,866
Derivative instruments designated as hedging instruments \| Foreign exchange contracts
Derivative Instruments
Notional Amount	86,167	90,245
Derivative Asset [Abstract]
Derivative assets - Fair value	0	0
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	1,586	611
Derivative instruments not designated as hedging instruments
Derivative Instruments
Notional Amount	20,540,031	15,222,341
Derivative Asset [Abstract]
Derivative assets - Fair value	330,316	107,816
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	251,744	111,828
Derivative instruments not designated as hedging instruments \| Interest rate contracts
Derivative Instruments
Notional Amount	15,489,692	11,695,499
Derivative Asset [Abstract]
Derivative assets - Fair value	192,883	69,818
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	124,119	69,267
Derivative instruments not designated as hedging instruments \| Foreign exchange contracts
Derivative Instruments
Notional Amount	4,839,661	3,407,522
Derivative Asset [Abstract]
Derivative assets - Fair value	54,637	21,624
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	47,024	19,329
Derivative instruments not designated as hedging instruments \| Credit contracts
Derivative Instruments
Notional Amount	210,678	119,320
Derivative Asset [Abstract]
Derivative assets - Fair value	2	1
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	84	164
Derivative instruments not designated as hedging instruments \| Equity warrants
Derivative Instruments
Notional Amount	0	0
Derivative Asset [Abstract]
Derivative assets - Fair value	1,414	1,951
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	0	0
Derivative instruments not designated as hedging instruments \| Commodity contracts
Derivative Instruments
Notional Amount	0	0
Derivative Asset [Abstract]
Derivative assets - Fair value	81,380	14,422
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	$ 80,517	$ 23,068
Derivative instruments not designated as hedging instruments \| Equity, Public Companies
Derivative Liability [Abstract]
Number of companies that Issued the equity contracts (Issuers Portion Only) \| company	3	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) \| company	18	18

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

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