Fair Value (Carrying Amounts and Estimated Fair Values of Company's Financial Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financial Assets:
Interest-bearing Time Deposits with Banks	$ 1,241	$ 1,241
Loans, Net	3,072,104	3,041,213
Financial Liabilities:
Time Deposits	(446,770)	(494,452)
Level 1
Financial Assets:
Cash and Short-term Investments	102,758	57,972
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	(3,931,903)	(3,612,078)
Time Deposits	0	0
Short-term Borrowings	0	0
Long-term Debt	0	0
Accrued Interest Payable	0	0
Level 2
Financial Assets:
Cash and Short-term Investments	290,486	287,776
Interest-bearing Time Deposits with Banks	1,241	1,241
Loans, Net	0	0
Accrued Interest Receivable	7,144	6,137
Financial Liabilities:
Demand, Savings, and Money Market Deposits	0	0
Time Deposits	(446,842)	(495,171)
Short-term Borrowings	(39,863)	(52,905)
Long-term Debt	(79,865)	(88,342)
Accrued Interest Payable	(1,253)	(1,049)
Level 3
Financial Assets:
Cash and Short-term Investments	0	0
Interest-bearing Time Deposits with Banks	0	0
Loans, Net	3,067,070	3,032,690
Accrued Interest Receivable	13,141	14,141
Financial Liabilities:
Demand, Savings, and Money Market Deposits	0	0
Time Deposits	0	0
Short-term Borrowings	0	0
Long-term Debt	(51,180)	(54,960)
Accrued Interest Payable	(33)	(35)
Carrying Value
Financial Assets:
Cash and Short-term Investments	393,244	345,748
Interest-bearing Time Deposits with Banks	1,241	1,241
Loans, Net	3,058,470	3,026,340
Accrued Interest Receivable	20,285	20,278
Financial Liabilities:
Demand, Savings, and Money Market Deposits	(3,931,903)	(3,612,078)
Time Deposits	(446,770)	(494,452)
Short-term Borrowings	(39,863)	(52,905)
Long-term Debt	(133,684)	(141,624)
Accrued Interest Payable	(1,286)	(1,084)
Total
Financial Assets:
Cash and Short-term Investments	393,244	345,748
Interest-bearing Time Deposits with Banks	1,241	1,241
Loans, Net	3,067,070	3,032,690
Accrued Interest Receivable	20,285	20,278
Financial Liabilities:
Demand, Savings, and Money Market Deposits	(3,931,903)	(3,612,078)
Time Deposits	(446,842)	(495,171)
Short-term Borrowings	(39,863)	(52,905)
Long-term Debt	(131,045)	(143,302)
Accrued Interest Payable	$ (1,286)	$ (1,084)