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Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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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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Fair value of asset associated with financial liability or 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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Derivatives (Notional and Fair Values) (Details) MMBTU in Thousands, Boe in Thousands, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020 USD ($) MMBTU Boe company	Mar. 31, 2019 MMBTU Boe	Dec. 31, 2019 USD ($) MMBTU Boe company
Derivative Asset [Abstract]
Derivative assets - Fair value	$ 834,204		$ 330,316
Less: Master netting agreements	(158,674)		(121,561)
Less: Cash collateral received/paid	(20,100)		(3,758)
Derivative asset, after netting	655,430		204,997
Derivative Liability [Abstract]
Derivative liabilities - Fair value	658,515		256,528
Less: Master netting agreements	(158,674)		(121,561)
Less: Cash collateral received/paid	(84,427)		(38,238)
Derivative liability, after netting	$ 415,414		$ 96,729
Crude oil \| Customer Counterparty
Derivative Liability [Abstract]
Derivative, nonmonetary notional amount, energy measure \| Boe	6,738		7,811
Natural gas \| Customer Counterparty
Derivative Liability [Abstract]
Derivative, nonmonetary notional amount, energy measure \| MMBTU	61,296		63,773
Derivative instruments designated as hedging instruments
Derivative Instruments
Notional amount	$ 186,281		$ 117,193
Derivative Asset [Abstract]
Derivative assets - Fair value	73		0
Derivative Liability [Abstract]
Derivative liabilities - Fair value	1,175		4,784
Derivative instruments designated as hedging instruments \| Interest rate contracts
Derivative Instruments
Notional amount	31,026		31,026
Derivative Asset [Abstract]
Derivative assets - Fair value	0		0
Derivative Liability [Abstract]
Derivative liabilities - Fair value	1,144		3,198
Derivative instruments designated as hedging instruments \| Foreign exchange contracts
Derivative Instruments
Notional amount	155,255		86,167
Derivative Asset [Abstract]
Derivative assets - Fair value	73		0
Derivative Liability [Abstract]
Derivative liabilities - Fair value	31		1,586
Derivatives not designated as hedging instruments
Derivative Instruments
Notional amount	21,826,497		20,540,031
Derivative Asset [Abstract]
Derivative assets - Fair value	834,131		330,316
Derivative Liability [Abstract]
Derivative liabilities - Fair value	657,340		251,744
Derivatives not designated as hedging instruments \| Interest rate contracts
Derivative Instruments
Notional amount	16,657,306		15,489,692
Derivative Asset [Abstract]
Derivative assets - Fair value	605,122		192,883
Derivative Liability [Abstract]
Derivative liabilities - Fair value	402,207		124,119
Derivatives not designated as hedging instruments \| Foreign exchange contracts
Derivative Instruments
Notional amount	4,958,834		4,839,661
Derivative Asset [Abstract]
Derivative assets - Fair value	64,310		54,637
Derivative Liability [Abstract]
Derivative liabilities - Fair value	55,627		47,024
Derivatives not designated as hedging instruments \| Credit contracts
Derivative Instruments
Notional amount	210,357		210,678
Derivative Asset [Abstract]
Derivative assets - Fair value	8		2
Derivative Liability [Abstract]
Derivative liabilities - Fair value	218		84
Derivatives not designated as hedging instruments \| Equity contracts
Derivative Instruments
Notional amount	0		0
Derivative Asset [Abstract]
Derivative assets - Fair value	1,128		1,414
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	163,563		81,380
Derivative Liability [Abstract]
Derivative liabilities - Fair value	$ 199,288		$ 80,517
Derivatives not designated as hedging instruments \| Equity, Public Companies
Derivative Liability [Abstract]
Number of companies that issued the equity (issuers portion only) \| company	2		3
Derivatives not designated as hedging instruments \| Equity, Private Companies
Derivative Liability [Abstract]
Number of companies that issued the equity (issuers portion only) \| company	18		18
Commodity contracts \| Derivatives not designated as hedging instruments \| Commodity contracts \| Customer Counterparty
Derivative Asset [Abstract]
Derivative assets - Fair value	$ 27,134		$ 40,065
Derivative Liability [Abstract]
Derivative liabilities - Fair value	167,127		42,140
Commodity contracts \| Derivatives not designated as hedging instruments \| Commodity contracts \| Crude oil \| Customer Counterparty
Derivative Asset [Abstract]
Derivative assets - Fair value	802		9,622
Derivative Liability [Abstract]
Derivative liabilities - Fair value	$ 133,988		6,099
Derivative, nonmonetary notional amount, energy measure \| Boe	6,738	7,811
Commodity contracts \| Derivatives not designated as hedging instruments \| Commodity contracts \| Natural gas \| Customer Counterparty
Derivative Asset [Abstract]
Derivative assets - Fair value	$ 26,332		30,443
Derivative Liability [Abstract]
Derivative liabilities - Fair value	$ 33,139		$ 36,041
Derivative, nonmonetary notional amount, energy measure \| MMBTU	61,296	63,773