Derivatives - Schedule of Derivatives Not Designated as Hedging Instruments (Details) MMBTU in Thousands, Boe in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026 USD ($) MMBTU Boe	Dec. 31, 2025 USD ($) Boe MMBTU
Derivative [Line Items]
Derivative assets - Fair value	$ 470,335	$ 409,467
Derivative liabilities - Fair value	433,751	385,973
Customer-related positions:
Derivative [Line Items]
Notional Amount	11,393,336	11,480,222
Derivative assets - Fair value	60,248	84,692
Derivative liabilities - Fair value	230,176	212,279
Economic hedges and other:
Derivative [Line Items]
Notional Amount	12,150,349	12,057,156
Derivative assets - Fair value	240,492	218,209
Derivative liabilities - Fair value	62,993	87,612
Interest rate contracts \| Customer-related positions:
Derivative [Line Items]
Notional Amount	9,174,398	9,474,603
Derivative assets - Fair value	29,679	47,759
Derivative liabilities - Fair value	213,046	208,714
Interest rate contracts \| Economic hedges and other:
Derivative [Line Items]
Notional Amount	9,212,330	9,512,674
Derivative assets - Fair value	215,458	210,802
Derivative liabilities - Fair value	30,132	48,017
Interest rate contracts \| Swaps \| Customer-related positions:
Derivative [Line Items]
Notional Amount	7,535,710	7,566,889
Derivative assets - Fair value	29,626	47,448
Derivative liabilities - Fair value	209,641	206,794
Interest rate contracts \| Swaps \| Economic hedges and other:
Derivative [Line Items]
Notional Amount	7,573,642	7,604,959
Derivative assets - Fair value	212,016	208,860
Derivative liabilities - Fair value	30,074	47,682
Interest rate contracts \| Written options \| Customer-related positions:
Derivative [Line Items]
Notional Amount	1,298,056	1,463,110
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	3,093	1,900
Interest rate contracts \| Collars and corridors \| Customer-related positions:
Derivative [Line Items]
Notional Amount	340,632	444,604
Derivative assets - Fair value	53	311
Derivative liabilities - Fair value	312	20
Interest rate contracts \| Collars and corridors \| Economic hedges and other:
Derivative [Line Items]
Notional Amount	340,632	444,605
Derivative assets - Fair value	312	20
Derivative liabilities - Fair value	58	335
Interest rate contracts \| Purchased options \| Economic hedges and other:
Derivative [Line Items]
Notional Amount	1,298,056	1,463,110
Derivative assets - Fair value	3,130	1,922
Derivative liabilities - Fair value	0	0
Foreign exchange contracts \| Customer-related positions:
Derivative [Line Items]
Notional Amount	2,218,938	2,005,619
Derivative assets - Fair value	30,569	36,933
Derivative liabilities - Fair value	17,130	3,565
Foreign exchange contracts \| Economic hedges and other:
Derivative [Line Items]
Notional Amount	2,938,019	2,544,482
Derivative assets - Fair value	25,034	7,407
Derivative liabilities - Fair value	32,861	39,595
Foreign exchange contracts \| Swaps \| Customer-related positions:
Derivative [Line Items]
Notional Amount	831,485	785,956
Derivative assets - Fair value	9,187	13,272
Derivative liabilities - Fair value	5,435	661
Foreign exchange contracts \| Swaps \| Economic hedges and other:
Derivative [Line Items]
Notional Amount	2,637,352	2,246,744
Derivative assets - Fair value	18,893	5,718
Derivative liabilities - Fair value	28,147	36,083
Foreign exchange contracts \| Written options \| Customer-related positions:
Derivative [Line Items]
Notional Amount	64,561	63,460
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	2,276	73
Foreign exchange contracts \| Forwards and spot \| Customer-related positions:
Derivative [Line Items]
Notional Amount	1,322,892	1,156,203
Derivative assets - Fair value	21,382	23,661
Derivative liabilities - Fair value	9,419	2,831
Foreign exchange contracts \| Forwards and spot \| Economic hedges and other:
Derivative [Line Items]
Notional Amount	236,106	234,278
Derivative assets - Fair value	3,863	1,602
Derivative liabilities - Fair value	4,712	3,498
Foreign exchange contracts \| Purchased options \| Economic hedges and other:
Derivative [Line Items]
Notional Amount	64,561	63,460
Derivative assets - Fair value	2,278	87
Derivative liabilities - Fair value	2	14
Commodity contracts \| Customer-related positions:
Derivative [Line Items]
Derivative assets - Fair value	122,427	7,919
Derivative liabilities - Fair value	34,012	67,251
Commodity contracts \| Customer-related positions: \| Crude Oil
Derivative [Line Items]
Derivative assets - Fair value	116,335	226
Derivative liabilities - Fair value	$ 2,410	$ 42,155
Derivative, nonmonetary notional amount, energy measure \| Boe	9,279	8,002
Commodity contracts \| Customer-related positions: \| Natural Gas
Derivative [Line Items]
Derivative assets - Fair value	$ 6,092	$ 7,693
Derivative liabilities - Fair value	$ 31,602	$ 25,096
Derivative, nonmonetary notional amount, energy measure \| MMBTU	141,370	184,544
Commodity contracts \| Economic hedges and other:
Derivative [Line Items]
Derivative assets - Fair value	$ 23,958	$ 58,103
Derivative liabilities - Fair value	88,076	4,907
Commodity contracts \| Economic hedges and other: \| Crude Oil
Derivative [Line Items]
Derivative assets - Fair value	1,523	34,033
Derivative liabilities - Fair value	$ 82,909	$ 32
Derivative, nonmonetary notional amount, energy measure \| Boe	9,279	8,002
Commodity contracts \| Economic hedges and other: \| Natural Gas
Derivative [Line Items]
Derivative assets - Fair value	$ 22,435	$ 24,070
Derivative liabilities - Fair value	$ 5,167	$ 4,875
Derivative, nonmonetary notional amount, energy measure \| MMBTU	138,815	179,471
Commodity contracts \| Swaps \| Customer-related positions: \| Crude Oil
Derivative [Line Items]
Derivative assets - Fair value	$ 66,760	$ 205
Derivative liabilities - Fair value	$ 2,410	$ 28,533
Derivative, nonmonetary notional amount, energy measure \| Boe	6,244	4,255
Commodity contracts \| Swaps \| Customer-related positions: \| Natural Gas
Derivative [Line Items]
Derivative assets - Fair value	$ 5,014	$ 5,814
Derivative liabilities - Fair value	$ 24,534	$ 18,403
Derivative, nonmonetary notional amount, energy measure \| MMBTU	89,873	112,599
Commodity contracts \| Swaps \| Economic hedges and other: \| Crude Oil
Derivative [Line Items]
Derivative assets - Fair value	$ 1,523	$ 25,309
Derivative liabilities - Fair value	$ 53,380	$ 11
Derivative, nonmonetary notional amount, energy measure \| Boe	6,244	4,255
Commodity contracts \| Swaps \| Economic hedges and other: \| Natural Gas
Derivative [Line Items]
Derivative assets - Fair value	$ 18,314	$ 18,258
Derivative liabilities - Fair value	$ 4,325	$ 3,963
Derivative, nonmonetary notional amount, energy measure \| MMBTU	88,528	110,506
Commodity contracts \| Collars \| Customer-related positions: \| Crude Oil
Derivative [Line Items]
Derivative assets - Fair value	$ 49,575	$ 21
Derivative liabilities - Fair value	$ 0	$ 13,622
Derivative, nonmonetary notional amount, energy measure \| Boe	3,035	3,747
Commodity contracts \| Collars \| Customer-related positions: \| Natural Gas
Derivative [Line Items]
Derivative assets - Fair value	$ 1,078	$ 1,879
Derivative liabilities - Fair value	$ 7,068	$ 6,693
Derivative, nonmonetary notional amount, energy measure \| MMBTU	51,497	71,945
Commodity contracts \| Collars \| Economic hedges and other: \| Crude Oil
Derivative [Line Items]
Derivative assets - Fair value	$ 0	$ 8,724
Derivative liabilities - Fair value	$ 29,529	$ 21
Derivative, nonmonetary notional amount, energy measure \| Boe	3,035	3,747
Commodity contracts \| Collars \| Economic hedges and other: \| Natural Gas
Derivative [Line Items]
Derivative assets - Fair value	$ 4,121	$ 5,812
Derivative liabilities - Fair value	$ 842	$ 912
Derivative, nonmonetary notional amount, energy measure \| MMBTU	50,287	68,965

Fair value, before effects of master netting arrangements, of a 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. Includes assets not subject to a master netting arrangement and elected not to be offset.

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- Definition

Fair value, before effects of master netting arrangements, of a 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. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Nominal energy measure used to calculate payments on a derivative instrument.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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