Fair Value - Carrying Amounts and Estimated Fair Values of Company's Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financial Assets:
Interest Bearing Time Deposits with Banks	$ 500	$ 500
Financial Liabilities:
Demand, Savings, and Money Market Deposits	(5,219,347)	(5,252,963)
Time Deposits	(836,955)	(767,042)
Carrying Value
Financial Assets:
Cash and Short-term Investments	123,470	115,330
Interest Bearing Time Deposits with Banks	500	500
Loans, Net	3,919,462	3,918,184
Accrued Interest Receivable	30,385	30,595
Financial Liabilities:
Demand, Savings, and Money Market Deposits	(4,382,392)	(4,485,921)
Time Deposits	(836,955)	(767,042)
Short-term Borrowings	(63,764)	(65,968)
Long-term Debt	(128,046)	(127,969)
Accrued Interest Payable	(9,236)	(7,073)
Estimate of Fair Value Measurement
Financial Assets:
Cash and Short-term Investments	123,470	115,330
Interest Bearing Time Deposits with Banks	500	500
Loans, Net	3,821,382	3,801,738
Accrued Interest Receivable	30,385	30,595
Financial Liabilities:
Demand, Savings, and Money Market Deposits	(4,382,392)	(4,485,921)
Time Deposits	(828,378)	(759,217)
Short-term Borrowings	(63,764)	(65,968)
Long-term Debt	(127,191)	(127,084)
Accrued Interest Payable	(9,236)	(7,073)
Estimate of Fair Value Measurement | Level 1
Financial Assets:
Cash and Short-term Investments	52,839	78,805
Interest Bearing Time Deposits with Banks	0	0
Loans, Net	0	0
Accrued Interest Receivable	0	0
Financial Liabilities:
Demand, Savings, and Money Market Deposits	(4,382,392)	(4,485,921)
Time Deposits	0	0
Short-term Borrowings	(25,000)	(25,000)
Long-term Debt	0	0
Accrued Interest Payable	0	0
Estimate of Fair Value Measurement | Level 2
Financial Assets:
Cash and Short-term Investments	70,631	36,525
Interest Bearing Time Deposits with Banks	500	500
Loans, Net	0	0
Accrued Interest Receivable	9,028	10,014
Financial Liabilities:
Demand, Savings, and Money Market Deposits	0	0
Time Deposits	(828,378)	(759,217)
Short-term Borrowings	(38,764)	(40,968)
Long-term Debt	(52,513)	(52,522)
Accrued Interest Payable	(8,768)	(6,701)
Estimate of Fair Value Measurement | Level 3
Financial Assets:
Cash and Short-term Investments	0	0
Interest Bearing Time Deposits with Banks	0	0
Loans, Net	3,821,382	3,801,738
Accrued Interest Receivable	21,357	20,581
Financial Liabilities:
Demand, Savings, and Money Market Deposits	0	0
Time Deposits	0	0
Short-term Borrowings	0	0
Long-term Debt	(74,678)	(74,562)
Accrued Interest Payable	$ (468)	$ (372)