Derivatives (Notional and Fair Values) (Details) MMBTU in Thousands, Boe in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) MMBTU Boe company	Dec. 31, 2019 USD ($) MMBTU Boe company
Derivative Asset [Abstract]
Derivative assets - Fair value	$ 602,754	$ 330,316
Less: Master Netting Arrangements	(93,063)	(121,561)
Less: Cash collateral received or paid	(8,449)	(3,758)
Derivative asset, after netting	501,242	204,997
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	424,828	256,528
Less: Master Netting Arrangements	(93,063)	(121,561)
Less: Cash collateral received/paid	(91,634)	(38,238)
Derivative liability, after netting	$ 240,131	$ 96,729
Customer Counterparty \| Crude Oil
Derivative Liability [Abstract]
Derivative, nonmonetary notional amount, energy measure \| Boe	6,321	7,811
Customer Counterparty \| Natural Gas
Derivative Liability [Abstract]
Derivative, nonmonetary notional amount, energy measure \| MMBTU	109,635	63,773
Derivative instruments designated as hedging instruments
Derivative Instruments
Notional Amount	$ 359,269	$ 117,193
Derivative Asset [Abstract]
Derivative assets - Fair value	0	0
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	2,099	4,784
Derivative instruments designated as hedging instruments \| Interest rate contracts \| Fair Value Hedging
Derivative Instruments
Notional Amount	0	31,026
Derivative Asset [Abstract]
Derivative assets - Fair value	0	0
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	0	3,198
Derivative instruments designated as hedging instruments \| Interest rate contracts \| Cash Flow Hedging
Derivative Instruments
Notional Amount	275,000	0
Derivative Asset [Abstract]
Derivative assets - Fair value	0	0
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	1,864	0
Derivative instruments designated as hedging instruments \| Foreign exchange contracts \| Net investment hedges
Derivative Instruments
Notional Amount	84,269	86,167
Derivative Asset [Abstract]
Derivative assets - Fair value	0	0
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	235	1,586
Derivative instruments not designated as hedging instruments
Derivative Instruments
Notional Amount	21,341,158	20,540,031
Derivative Asset [Abstract]
Derivative assets - Fair value	602,754	330,316
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	422,729	251,744
Derivative instruments not designated as hedging instruments \| Interest rate contracts
Derivative Instruments
Notional Amount	18,155,678	15,489,692
Derivative Asset [Abstract]
Derivative assets - Fair value	489,132	192,883
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	315,834	124,119
Derivative instruments not designated as hedging instruments \| Foreign exchange contracts
Derivative Instruments
Notional Amount	3,108,488	4,839,661
Derivative Asset [Abstract]
Derivative assets - Fair value	30,300	54,637
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	22,524	47,024
Derivative instruments not designated as hedging instruments \| Credit contracts
Derivative Instruments
Notional Amount	76,992	210,678
Derivative Asset [Abstract]
Derivative assets - Fair value	13	2
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	206	84
Derivative instruments not designated as hedging instruments \| Equity contracts
Derivative Instruments
Notional Amount	0	0
Derivative Asset [Abstract]
Derivative assets - Fair value	858	1,414
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	82,451	81,380
Derivative Liability [Abstract]
Derivative liabilities - Fair Value	$ 84,165	$ 80,517
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	2	3
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	17	18

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