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Fair Value Accounting and Measurement (Financial Assets And Liabilities Accounted for Fair Value On Recurring Basis) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | $ 5,210,134 | $ 3,746,142
Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 5,210,134 | 3,746,142
Loans held for sale | 14,760 |
Interest Rate Cash Flow Hedge Asset at Fair Value |  | 14,727
Fair Value, Inputs, Level 1 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
Loans held for sale | 0 |
Interest Rate Cash Flow Hedge Asset at Fair Value |  | 0
Fair Value, Inputs, Level 2 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 5,210,134 | 3,746,142
Loans held for sale | 14,760 |
Interest Rate Cash Flow Hedge Asset at Fair Value |  | 14,727
Fair Value, Inputs, Level 3 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
Loans held for sale | 0 |
Interest Rate Cash Flow Hedge Asset at Fair Value |  | 0
U.S. Government Agency and Sponsored Enterprise Mortgage-Back Securities and Collateralized Mortgage Obligations | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 3,814,387 | 2,892,950
U.S. Government Agency and Sponsored Enterprise Mortgage-Back Securities and Collateralized Mortgage Obligations | Fair Value, Inputs, Level 1 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
U.S. Government Agency and Sponsored Enterprise Mortgage-Back Securities and Collateralized Mortgage Obligations | Fair Value, Inputs, Level 2 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 3,814,387 | 2,892,950
U.S. Government Agency and Sponsored Enterprise Mortgage-Back Securities and Collateralized Mortgage Obligations | Fair Value, Inputs, Level 3 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
Asset-backed Securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 357,479 | 196,050
Asset-backed Securities | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 357,479 | 196,050
Asset-backed Securities | Fair Value, Inputs, Level 1 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
Asset-backed Securities | Fair Value, Inputs, Level 2 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 357,479 | 196,050
Asset-backed Securities | Fair Value, Inputs, Level 3 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
State and Municipal Securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 753,572 | 488,802
State and Municipal Securities | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 753,572 | 488,802
State and Municipal Securities | Fair Value, Inputs, Level 1 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
State and Municipal Securities | Fair Value, Inputs, Level 2 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 753,572 | 488,802
State and Municipal Securities | Fair Value, Inputs, Level 3 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
U.S. Government Agency | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 284,696 | 168,340
U.S. Government Agency | Fair Value, Inputs, Level 1 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
U.S. Government Agency | Fair Value, Inputs, Level 2 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 284,696 | 168,340
U.S. Government Agency | Fair Value, Inputs, Level 3 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 0 | 0
Interest Rate Lock Commitments | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate derivative assets, at fair value | 1,096 |
Interest Rate Lock Commitments | Fair Value, Inputs, Level 1 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate derivative assets, at fair value | 0 |
Interest Rate Lock Commitments | Fair Value, Inputs, Level 2 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate derivative assets, at fair value | 0 |
Interest Rate Lock Commitments | Fair Value, Inputs, Level 3 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate derivative assets, at fair value | 1,096 |
Interest Rate Swap | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate derivative assets, at fair value | 46,184 | 19,144
Interest rate derivative liabilities, at fair value | 46,637 | 19,145
Interest Rate Swap | Fair Value, Inputs, Level 1 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate derivative assets, at fair value | 0 | 0
Interest rate derivative liabilities, at fair value | 0 | 0
Interest Rate Swap | Fair Value, Inputs, Level 2 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate derivative assets, at fair value | 46,184 | 19,144
Interest rate derivative liabilities, at fair value | 46,637 | 19,145
Interest Rate Swap | Fair Value, Inputs, Level 3 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate derivative assets, at fair value | 0 | 0
Interest rate derivative liabilities, at fair value | 0 | $ 0
Forward sales contracts | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Liabilities | 165 |
Forward sales contracts | Fair Value, Inputs, Level 1 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Liabilities | 0 |
Forward sales contracts | Fair Value, Inputs, Level 2 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Liabilities | 165 |
Forward sales contracts | Fair Value, Inputs, Level 3 | Fair Value, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Liabilities | $ 0 |

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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, after the effects of master netting arrangements, of a financial liability or 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 liabilities 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 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 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 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 + Details
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