Securities (Narrative) (Details) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2023 USD ($) security $ / shares shares	Dec. 31, 2022 USD ($) security
Debt and Equity Securities, FV-NI [Line Items]
Private mortgage-backed security fair value	$ 800	$ 800
Debt securities, available-for-sale and held-to-maturity, number of positions | security	656	666
Number of securities held in an unrealized loss position | security	652	644
Investment securities, pledged as collateral for public deposits	$ 1,600,000	$ 758,000
FHLB stock and FRB stock, cost	55,400	39,600
FHLB, cost	22,600	14,700
FRB stock	32,800	$ 24,900
GrandSouth
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, gain (loss)	$ 0
Visa, Inc | Common Class B
Debt and Equity Securities, FV-NI [Line Items]
Stock owned (in shares) | shares	12,356
Carrying value of shares	$ 0
Visa, Inc | Common Class A
Debt and Equity Securities, FV-NI [Line Items]
Conversion price (in dollars per share) | $ / shares	$ 1.5875
Conversion of stock (in shares) | shares	19,615