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Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2024 segment office	Jun. 02, 2003 shares
Financing Receivable, Past Due [Line Items]
Bank common stock exchanged for company common stock (in shares) | shares			1
Number of branch offices | office		7
Number of reportable segments | segment		1
MHC
Financing Receivable, Past Due [Line Items]
Allowance for credit loss, increase (decrease)	$ (5.8)
C&I
Financing Receivable, Past Due [Line Items]
Allowance for credit loss, increase (decrease)	$ 4.6

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