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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 | Jun. 30, 2021 | Dec. 31, 2020
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Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Securities available for sale |  | $ 902,845 | $ 628,059
Securities held to maturity, fair value |  | 226,044 | 282,035
Carrying Amount [Member] | Level 1 Inputs [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Cash and cash equivalents |  | 206,387 | 93,878
Accrued interest receivable |  | 15,431 | 15,635
Non-maturity deposits |  | 3,717,939 | 3,392,774
Short-term borrowings |  |  | 5,300
Accrued interest payable |  | 2,868 | 4,381
Carrying Amount [Member] | Level 2 Inputs [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Securities available for sale |  | 902,845 | 628,059
Securities held to maturity, fair value |  | 218,858 | 271,973
Loans held for sale |  | 3,929 | 4,305
Loans |  | 3,532,535 | 3,513,284
Long-lived assets held for sale |  | 1,118 |
FHLB and FRB stock |  | 9,154 | 8,619
Time deposits |  | 941,282 | 885,593
Long-term borrowings |  | 73,756 | 73,623
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 |  | 1,004 |
Derivative instruments, liabilities |  |  | 311
Carrying Amount [Member] | Level 2 Inputs [Member] | Interest Rate Products [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Derivative instruments, assets |  | 15,108 | 19,626
Derivative instruments, liabilities |  | 14,972 | 19,837
Carrying Amount [Member] | Level 2 Inputs [Member] | Credit Contract [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Derivative instruments, assets |  | 14 | 23
Derivative instruments, liabilities |  | 53 | 86
Carrying Amount [Member] | Level 2 Inputs [Member] | Mortgage Banking [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Derivative instruments, assets |  | 317 | 471
Derivative instruments, liabilities |  | 39 | 1
Carrying Amount [Member] | Level 3 Inputs [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Loans | [1] | 53,268 | 29,434
Estimated Fair Value [Member] | Level 1 Inputs [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Cash and cash equivalents |  | 206,387 | 93,878
Accrued interest receivable |  | 15,431 | 15,635
Non-maturity deposits |  | 3,717,939 | 3,392,774
Short-term borrowings |  |  | 5,300
Accrued interest payable |  | 2,868 | 4,381
Estimated Fair Value [Member] | Level 2 Inputs [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Securities available for sale |  | 902,845 | 628,059
Securities held to maturity, fair value |  | 226,044 | 282,035
Loans held for sale |  | 3,929 | 4,305
Loans |  | 3,564,623 | 3,549,770
Long-lived assets held for sale |  | 1,118 |
FHLB and FRB stock |  | 9,154 | 8,619
Time deposits |  | 941,649 | 887,113
Long-term borrowings |  | 78,286 | 83,953
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 |  | 1,004 |
Derivative instruments, liabilities |  |  | 311
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 |  | 15,108 | 19,626
Derivative instruments, liabilities |  | 14,972 | 19,837
Estimated Fair Value [Member] | Level 2 Inputs [Member] | Credit Contract [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Derivative instruments, assets |  | 14 | 23
Derivative instruments, liabilities |  | 53 | 86
Estimated Fair Value [Member] | Level 2 Inputs [Member] | Mortgage Banking [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Derivative instruments, assets |  | 317 | 471
Derivative instruments, liabilities |  | 39 | 1
Estimated Fair Value [Member] | Level 3 Inputs [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Loans | [1] | $ 53,268 | $ 29,434
[1] | Comprised of collateral dependent loans.

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563 + Details
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- Definition 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. + References No definition available. + Details
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- Definition 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. + References No definition available. + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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- Definition Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock. + References No definition available. + Details
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