Fair Value (Carrying Amounts and Estimated Fair Values of Company's Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financial Assets:
Interest Bearing Time Deposits with Banks	$ 1,241	$ 1,985
Loans, Net	3,041,213	3,060,813
Financial Liabilities:
Demand, Savings, and Money Market Deposits	(4,106,530)	(3,430,021)
Time Deposits	(494,452)	(631,396)
Short-term Borrowings	(52,905)	(167,736)
Long-term Debt	(141,624)	(181,950)
Reported Value Measurement
Financial Assets:
Cash and Short-term Investments	345,748	103,884
Interest Bearing Time Deposits with Banks	1,241	1,985
Loans, Net	3,026,340	3,058,211
Accrued Interest Receivable	20,278	18,425
Financial Liabilities:
Demand, Savings, and Money Market Deposits	(3,612,078)	(2,798,625)
Time Deposits	(494,452)	(631,396)
Short-term Borrowings	(52,905)	(167,736)
Long-term Debt	(141,624)	(181,950)
Accrued Interest Payable	(1,084)	(2,442)
Estimate of Fair Value Measurement
Financial Assets:
Cash and Short-term Investments	345,748	103,884
Interest Bearing Time Deposits with Banks	1,241	1,985
Loans, Net	3,032,690	3,056,521
Accrued Interest Receivable	20,278	18,425
Financial Liabilities:
Demand, Savings, and Money Market Deposits	(3,612,078)	(2,798,625)
Time Deposits	(495,171)	(624,666)
Short-term Borrowings	(52,905)	(167,736)
Long-term Debt	(143,302)	(182,408)
Accrued Interest Payable	(1,084)	(2,442)
Estimate of Fair Value Measurement \| Level 1
Financial Assets:
Cash and Short-term Investments	57,972	59,971
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	(3,612,078)	(2,798,625)
Time Deposits	0	0
Short-term Borrowings	0	(128,311)
Long-term Debt	0	0
Accrued Interest Payable	0	0
Estimate of Fair Value Measurement \| Level 2
Financial Assets:
Cash and Short-term Investments	287,776	43,913
Interest Bearing Time Deposits with Banks	1,241	1,985
Loans, Net	0	0
Accrued Interest Receivable	6,137	4,400
Financial Liabilities:
Demand, Savings, and Money Market Deposits	0	0
Time Deposits	(495,171)	(624,666)
Short-term Borrowings	(52,905)	(39,425)
Long-term Debt	(88,342)	(127,174)
Accrued Interest Payable	(1,049)	(2,376)
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	3,032,690	3,056,521
Accrued Interest Receivable	14,141	14,025
Financial Liabilities:
Demand, Savings, and Money Market Deposits	0	0
Time Deposits	0	0
Short-term Borrowings	0	0
Long-term Debt	(54,960)	(55,234)
Accrued Interest Payable	$ (35)	$ (66)

Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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