Note B - Investment Securities - Schedule of Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Within one year, amortized cost	$ 3,078
Within one year, fair value	3,076
After 1 through 5 years, amortized cost	130,736
After 1 through 5 years, fair value	117,230
After 5 through 10 years, amortized cost	35,930
After 5 through 10 years, fair value	33,999
After 10 years, amortized cost	104,550
After 10 years, fair value	95,231
Mortgage and asset-backed securities, amortized cost	493,462
Mortgage and asset-backed securities, fair value	446,341
Debt Securities, Available-for-Sale, Amortized Cost	767,756	$ 754,425
Debt Securities, Available-for-Sale	$ 695,877	$ 673,413

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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