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Fair Value Measurements (Carrying Amount, Estimated Fair Value, and Placement in Fair Value Hierarchy of Financial Instruments) (Details) - USD ($) $ in Thousands		Mar. 31, 2022	Dec. 31, 2021
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Securities available for sale		$ 1,119,362	$ 1,178,515
Securities held to maturity, fair value		206,367	209,820
Carrying Amount [Member] | Level 1 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash and cash equivalents		170,404	79,112
Accrued interest receivable		16,004	15,482
Non-maturity deposits		4,085,737	3,905,136
Short-term borrowings			30,000
Accrued interest payable		2,794	2,147
Carrying Amount [Member] | Level 2 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Securities available for sale		1,119,362	1,178,515
Securities held to maturity, fair value		211,173	205,581
Loans held for sale		5,544	6,202
Loans		3,660,936	3,606,276
Long-lived assets held for sale		2,560	2,560
FHLB and FRB stock		9,457	10,770
Time deposits		917,195	921,954
Long-term borrowings		73,989	73,911
Carrying Amount [Member] | Level 2 Inputs [Member] | Cash Flow Hedge of Interest Rate Risk [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets		4,031	1,559
Derivative instruments, liabilities			0
Carrying Amount [Member] | Level 2 Inputs [Member] | Interest Rate Products [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets		21,010	14,702
Derivative instruments, liabilities		21,016	14,708
Carrying Amount [Member] | Level 2 Inputs [Member] | Credit Contract [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets		0	0
Derivative instruments, liabilities		0	1
Carrying Amount [Member] | Level 2 Inputs [Member] | Mortgage Banking [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets		151	243
Derivative instruments, liabilities		155	4
Carrying Amount [Member] | Level 3 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Loans	[1]	31,746	33,484
Estimated Fair Value [Member] | Level 1 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash and cash equivalents		170,404	79,112
Accrued interest receivable		16,004	15,482
Non-maturity deposits		4,085,737	3,905,136
Short-term borrowings			30,000
Accrued interest payable		2,794	2,147
Estimated Fair Value [Member] | Level 2 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Securities available for sale		1,119,362	1,178,515
Securities held to maturity, fair value		206,367	209,820
Loans held for sale		5,544	6,202
Loans		3,661,983	3,642,351
Long-lived assets held for sale		2,560	2,560
FHLB and FRB stock		9,457	10,770
Time deposits		912,674	920,699
Long-term borrowings		73,535	77,792
Estimated Fair Value [Member] | Level 2 Inputs [Member] | Cash Flow Hedge of Interest Rate Risk [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets		4,031	1,559
Derivative instruments, liabilities			0
Estimated Fair Value [Member] | Level 2 Inputs [Member] | Interest Rate Products [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets		21,010	14,702
Derivative instruments, liabilities		21,016	14,708
Estimated Fair Value [Member] | Level 2 Inputs [Member] | Credit Contract [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets		0	0
Derivative instruments, liabilities		0	1
Estimated Fair Value [Member] | Level 2 Inputs [Member] | Mortgage Banking [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets		151	243
Derivative instruments, liabilities		155	4
Estimated Fair Value [Member] | Level 3 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Loans	[1]	$ 31,746	$ 33,484
[1] Comprised of collateral dependent loans.

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Fair value portion of liabilities incurred for goods and services received that are used in an entity's business and related party payables.

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Fair value portion of assets classified as held for sale.

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Amount 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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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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