Derivatives (Notional and Fair Values) (Details) MMBTU in Thousands, Boe in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022 USD ($) MMBTU Boe company	Dec. 31, 2021 USD ($) Boe MMBTU company
Derivative Asset [Abstract]
Derivative assets - Fair value	$ 689,100	$ 484,184
Less: Master netting agreements	(108,782)	(58,679)
Less: Cash collateral received/paid	(81,534)	(42,274)
Net derivative assets	498,784	383,231
Derivative Liability [Abstract]
Derivative liabilities - Fair value	692,029	390,171
Less: Master netting agreements	(108,782)	(58,679)
Less: Cash collateral received/paid	(326,299)	(174,048)
Net derivative liabilities	$ 256,948	$ 157,444
Crude oil \| Customer Counterparty
Derivative Liability [Abstract]
Derivative, nonmonetary notional amount, energy measure \| Boe	7,217	7,519
Natural gas \| Customer Counterparty
Derivative Liability [Abstract]
Derivative, nonmonetary notional amount, energy measure \| MMBTU	83,460	83,274
Derivative instruments designated as hedging instruments
Derivative Instruments
Notional Amount	$ 1,361,751	$ 361,531
Derivative Asset [Abstract]
Derivative assets - Fair value	385	0
Derivative Liability [Abstract]
Derivative liabilities - Fair value	490	282
Derivative instruments designated as hedging instruments \| Cash Flow Hedging \| Interest rate contracts
Derivative Instruments
Notional Amount	1,275,000	275,000
Derivative Asset [Abstract]
Derivative assets - Fair value	385	0
Derivative Liability [Abstract]
Derivative liabilities - Fair value	0	57
Derivative instruments designated as hedging instruments \| Net Investment Hedging \| Foreign exchange contracts
Derivative Instruments
Notional Amount	86,751	86,531
Derivative Asset [Abstract]
Derivative assets - Fair value	0	0
Derivative Liability [Abstract]
Derivative liabilities - Fair value	490	225
Derivatives not designated as hedging instruments
Derivative Instruments
Notional Amount	20,259,808	19,522,661
Derivative Asset [Abstract]
Derivative assets - Fair value	688,715	484,184
Derivative Liability [Abstract]
Derivative liabilities - Fair value	691,539	389,889
Derivatives not designated as hedging instruments \| Interest rate contracts
Derivative Instruments
Notional Amount	17,771,724	17,575,420
Derivative Asset [Abstract]
Derivative assets - Fair value	187,716	240,222
Derivative Liability [Abstract]
Derivative liabilities - Fair value	236,569	179,905
Derivatives not designated as hedging instruments \| Foreign exchange contracts
Derivative Instruments
Notional Amount	2,365,524	1,874,681
Derivative Asset [Abstract]
Derivative assets - Fair value	16,122	21,033
Derivative Liability [Abstract]
Derivative liabilities - Fair value	11,545	15,276
Derivatives not designated as hedging instruments \| Credit contracts
Derivative Instruments
Notional Amount	122,560	72,560
Derivative Asset [Abstract]
Derivative assets - Fair value	0	0
Derivative Liability [Abstract]
Derivative liabilities - Fair value	67	141
Derivatives not designated as hedging instruments \| Equity contracts
Derivative Instruments
Notional Amount	0	0
Derivative Asset [Abstract]
Derivative assets - Fair value	314	220
Derivative Liability [Abstract]
Derivative liabilities - Fair value	0	0
Derivatives not designated as hedging instruments \| Commodity contracts
Derivative Instruments
Notional Amount	0	0
Derivative Asset [Abstract]
Derivative assets - Fair value	484,563	222,709
Derivative Liability [Abstract]
Derivative liabilities - Fair value	$ 443,358	$ 194,567
Derivatives not designated as hedging instruments \| Equity, Public Companies
Derivative Liability [Abstract]
Number of companies that issued the equity (issuers portion only) \| company	1	1
Derivatives not designated as hedging instruments \| Equity, Private Companies
Derivative Liability [Abstract]
Number of companies that issued the equity (issuers portion only) \| company	13	12

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