Income Taxes - Schedule of Reconciliation of Federal Statutory Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Amount
Statutory U.S. federal tax rate	$ 362,347	$ 311,191	$ 306,552
Tax credits
Tax credits and benefits under the PAM, net of amortization	(29,268)	(26,147)	(4,299)
Energy tax credit — solar	(42,406)	(52,722)	(70,364)
Energy tax credit — energy storage	(34,408)	(11,143)	0
New markets tax credit	0	0	(21,378)
Other tax credits	(23,802)	(18,906)	(34,076)
Changes in valuation allowance	13,353	0	0
Nontaxable or nondeductible items
Nondeductible FDIC insurance premiums	8,474	7,719	7,007
Other nontaxable or nondeductible items	4,899		217
Other nontaxable or nondeductible items		(15,041)
Other, net	7,549	(3,879)	(4,544)
U.S. state and local income taxes, net of U.S. federal income tax effect	125,638	116,091	118,236
Foreign tax effects	7,805	8,165	835
Changes in unrecognized tax benefits	91	947	423
Income tax expense	$ 400,272	$ 316,275	$ 298,609
Percent
Statutory U.S. federal tax rate	21.00%	21.00%	21.00%
Tax credits
Tax credits and benefits under the PAM, net of amortization	(1.70%)	(1.80%)	(0.30%)
Energy tax credit — solar	(2.50%)	(3.50%)	(4.80%)
Energy tax credit — energy storage	(2.00%)	(0.70%)	0.00%
New markets tax credit	0.00%	0.00%	(1.50%)
Other tax credits	(1.40%)	(1.30%)	(2.30%)
Changes in valuation allowance	0.80%	0.00%	0.00%
Nontaxable or nondeductible items
Nondeductible FDIC insurance premiums	0.50%	0.50%	0.50%
Other nontaxable or nondeductible items	0.30%		0.00%
Other nontaxable or nondeductible items		(1.00%)
Other, net	0.40%	(0.30%)	(0.30%)
U.S. state income taxes, net of U.S. federal income tax effect	7.30%	7.80%	8.10%
Foreign tax effects	0.50%	0.50%	0.10%
Changes in unrecognized tax benefits	0.00%	0.10%	0.00%
Effective tax rate	23.20%	21.30%	20.50%