Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended
Employee Benefit Plans (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Mar. 31, 2025
Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 904	$ 921
Expected return on assets	(1,017)	(1,019)
Net loss amortization	633	593
Net periodic benefit cost (income)	520	495
Retirement Plan Acquired
Defined Benefit Plan Disclosure [Line Items]
Interest cost	0	28
Expected return on assets	0	(34)
Net loss amortization	0	0
Net periodic benefit cost (income)	0	(6)
Restoration Plan
Defined Benefit Plan Disclosure [Line Items]
Interest cost	228	224
Expected return on assets	0	0
Net loss amortization	34	21
Net periodic benefit cost (income)	$ 262	$ 245

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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+ Details

SOUTHSIDE BANCSHARES INC 10-Q