Income Taxes - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Operating Loss Carryforwards [Line Items]
Net operating loss	$ 523	$ 805
Franklin Financial Network, Inc.
Operating Loss Carryforwards [Line Items]
Net operating loss	$ 2,491	$ 3,835

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

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Balance Type:	debit
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