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Loans and Allowance for Credit Losses - Age Analysis of Past Due Loans by Segment (Detail) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
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Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | $ 6,703,481 |  |
Loans | 6,761,183 | $ 6,189,148 | $ 5,774,139
Financing Receivable, Past Due | 57,702 |  |
Loans and Leases Receivable, Gross | 6,761,183 |  |
Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 811,180 |  |
Loans | 815,815 | 699,375 |
Financing Receivable, Past Due | 4,635 |  |
Loans and Leases Receivable, Gross | 815,815 |  |
Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 1,552,349 |  |
Loans | 1,555,986 | 1,241,853 |
Financing Receivable, Past Due | 3,637 |  |
Loans and Leases Receivable, Gross | 1,555,986 |  |
Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 426,231 |  |
Loans | 427,221 | 449,039 |
Financing Receivable, Past Due | 990 |  |
Loans and Leases Receivable, Gross | 427,221 |  |
Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 1,737,624 |  |
Loans | 1,750,592 | 1,681,362 |
Financing Receivable, Past Due | 12,968 |  |
Loans and Leases Receivable, Gross | 1,750,592 |  |
Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 2,176,097 |  |
Loans | 2,211,569 | 2,117,519 |
Financing Receivable, Past Due | 35,472 |  |
Loans and Leases Receivable, Gross | 2,211,569 |  |
Time and demand loans | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 1,537,917 |  |
Loans | 1,541,382 |  |
Financing Receivable, Past Due | 3,465 |  |
Loans and Leases Receivable, Gross | 1,541,382 |  |
Commercial credit cards | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 14,432 |  |
Loans | 14,604 |  |
Financing Receivable, Past Due | 172 |  |
Loans and Leases Receivable, Gross | 14,604 |  |
Senior Lien | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 1,144,323 |  |
Senior Lien | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 1,138,132 |  |
Financing Receivable, Past Due | 6,191 |  |
Loans and Leases Receivable, Gross | 1,144,323 |  |
Junior Lien | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 606,269 |  |
Junior Lien | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 599,492 |  |
Financing Receivable, Past Due | 6,777 |  |
Loans and Leases Receivable, Gross | 606,269 |  |
Multifamily | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 371,239 |  |
Multifamily | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 370,779 |  |
Financing Receivable, Past Due | 460 |  |
Loans and Leases Receivable, Gross | 371,239 |  |
Nonowner Occupied Commercial Real Estate | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 1,421,151 |  |
Nonowner Occupied Commercial Real Estate | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 1,389,207 |  |
Financing Receivable, Past Due | 31,944 |  |
Loans and Leases Receivable, Gross | 1,421,151 |  |
Owner Occupied Commercial Real Estate | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 419,179 |  |
Owner Occupied Commercial Real Estate | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 416,111 |  |
Financing Receivable, Past Due | 3,068 |  |
Loans and Leases Receivable, Gross | 419,179 |  |
Automobile Loan | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 709,938 |  |
Financing Receivable, Past Due | 2,862 |  |
Loans and Leases Receivable, Gross | 712,800 |  |
Automobile Loan | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 712,800 |  |
Consumer Credit Cards | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 12,146 |  |
Financing Receivable, Past Due | 214 |  |
Loans and Leases Receivable, Gross | 12,360 |  |
Consumer Credit Cards | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 12,360 |  |
Other consumer loans | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Current | 89,096 |  |
Financing Receivable, Past Due | 1,559 |  |
Loans and Leases Receivable, Gross | 90,655 |  |
Other consumer loans | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 90,655 |  |
Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 699,375 | 590,739
Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 449,039 | 358,978
Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 1,241,853 | 1,138,473
Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 1,681,362 | 1,562,405
Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 2,117,519 | $ 2,123,544
Financial Asset, 30 to 59 Days Past Due [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 8,072 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 2,870 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 146 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 936 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 3,883 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 237 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Time and demand loans | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 97 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial credit cards | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 49 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Senior Lien | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 1,775 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Junior Lien | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 2,108 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Multifamily | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 0 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Nonowner Occupied Commercial Real Estate | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 18 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Owner Occupied Commercial Real Estate | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 219 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Automobile Loan | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 2,090 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer Credit Cards | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 52 |  |
Financial Asset, 30 to 59 Days Past Due [Member] | Other consumer loans | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 728 |  |
Financial Asset, 60 to 89 Days Past Due [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 2,566 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 852 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 62 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 0 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 1,492 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 160 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Time and demand loans | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 28 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial credit cards | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 34 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Senior Lien | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 660 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Junior Lien | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 832 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Multifamily | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 0 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Nonowner Occupied Commercial Real Estate | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 104 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Owner Occupied Commercial Real Estate | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 56 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Automobile Loan | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 417 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer Credit Cards | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 39 |  |
Financial Asset, 60 to 89 Days Past Due [Member] | Other consumer loans | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 396 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 1,523 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 639 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 112 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 0 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 769 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 3 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Time and demand loans | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 23 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial credit cards | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 89 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Senior Lien | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 267 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Junior Lien | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 502 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Multifamily | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 0 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Nonowner Occupied Commercial Real Estate | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 0 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Owner Occupied Commercial Real Estate | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 3 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Automobile Loan | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 94 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Credit Cards | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 123 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Other consumer loans | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 422 |  |
Nonaccrual Commercial Loans [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 45,541 |  |
Nonaccrual Commercial Loans [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 274 |  |
Nonaccrual Commercial Loans [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 3,317 |  |
Nonaccrual Commercial Loans [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 54 |  |
Nonaccrual Commercial Loans [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 6,824 |  |
Nonaccrual Commercial Loans [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 35,072 |  |
Nonaccrual Commercial Loans [Member] | Time and demand loans | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 3,317 |  |
Nonaccrual Commercial Loans [Member] | Commercial credit cards | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 0 |  |
Nonaccrual Commercial Loans [Member] | Senior Lien | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 3,489 |  |
Nonaccrual Commercial Loans [Member] | Junior Lien | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 3,335 |  |
Nonaccrual Commercial Loans [Member] | Multifamily | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 460 |  |
Nonaccrual Commercial Loans [Member] | Nonowner Occupied Commercial Real Estate | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 31,822 |  |
Nonaccrual Commercial Loans [Member] | Owner Occupied Commercial Real Estate | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 2,790 |  |
Nonaccrual Commercial Loans [Member] | Automobile Loan | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 261 |  |
Nonaccrual Commercial Loans [Member] | Consumer Credit Cards | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | 0 |  |
Nonaccrual Commercial Loans [Member] | Other consumer loans | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due | $ 13 |  |
Originated Loans [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total past due and nonaccrual |  | 34,741 |
Current |  | 5,679,632 |
Loans |  | 5,714,373 |
Loans and Leases Receivable, Gross |  | 5,714,373 |
Originated Loans [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 685,416 |
Loans and Leases Receivable, Gross |  | 685,416 |
Originated Loans [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 1,212,026 |
Loans and Leases Receivable, Gross |  | 1,212,026 |
Originated Loans [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 442,777 |
Loans and Leases Receivable, Gross |  | 442,777 |
Originated Loans [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 1,415,808 |
Loans and Leases Receivable, Gross |  | 1,415,808 |
Originated Loans [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 1,958,346 |
Loans and Leases Receivable, Gross |  | 1,958,346 |
Originated Loans [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total past due and nonaccrual |  | 6,328 |
Current |  | 679,088 |
Loans |  | 685,416 |
Originated Loans [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total past due and nonaccrual |  | 207 |
Current |  | 442,570 |
Loans |  | 442,777 |
Originated Loans [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total past due and nonaccrual |  | 9,368 |
Current |  | 1,202,658 |
Loans |  | 1,212,026 |
Originated Loans [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total past due and nonaccrual |  | 11,888 |
Current |  | 1,403,920 |
Loans |  | 1,415,808 |
Originated Loans [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total past due and nonaccrual |  | 6,950 |
Current |  | 1,951,396 |
Loans |  | 1,958,346 |
Originated Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 8,643 |
Originated Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 4,070 |
Originated Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 198 |
Originated Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 391 |
Originated Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 3,757 |
Originated Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 227 |
Originated Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 1,940 |
Originated Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 1,020 |
Originated Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 0 |
Originated Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 57 |
Originated Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 749 |
Originated Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 114 |
Originated Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 1,816 |
Originated Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 931 |
Originated Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 9 |
Originated Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 140 |
Originated Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 736 |
Originated Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 0 |
Originated Loans [Member] | Nonaccrual Commercial Loans [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 22,342 |
Originated Loans [Member] | Nonaccrual Commercial Loans [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 307 |
Originated Loans [Member] | Nonaccrual Commercial Loans [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 0 |
Originated Loans [Member] | Nonaccrual Commercial Loans [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 8,780 |
Originated Loans [Member] | Nonaccrual Commercial Loans [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 6,646 |
Originated Loans [Member] | Nonaccrual Commercial Loans [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 6,609 |
Acquired Loans [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total past due and nonaccrual |  | 3,385 |
Current |  | 471,390 |
Loans |  | 474,775 |
Loans and Leases Receivable, Gross |  | 474,775 |
Acquired Loans [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 13,959 |
Loans and Leases Receivable, Gross |  | 13,959 |
Acquired Loans [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 29,827 |
Loans and Leases Receivable, Gross |  | 29,827 |
Acquired Loans [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 6,262 |
Loans and Leases Receivable, Gross |  | 6,262 |
Acquired Loans [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 265,554 |
Loans and Leases Receivable, Gross |  | 265,554 |
Acquired Loans [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  | 159,173 |
Loans and Leases Receivable, Gross |  | 159,173 |
Acquired Loans [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total past due and nonaccrual |  | 223 |
Current |  | 13,736 |
Loans |  | 13,959 |
Acquired Loans [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total past due and nonaccrual |  | 0 |
Current |  | 6,262 |
Loans |  | 6,262 |
Acquired Loans [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total past due and nonaccrual |  | 76 |
Current |  | 29,751 |
Loans |  | 29,827 |
Acquired Loans [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total past due and nonaccrual |  | 2,681 |
Current |  | 262,873 |
Loans |  | 265,554 |
Acquired Loans [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total past due and nonaccrual |  | 405 |
Current |  | 158,768 |
Loans |  | 159,173 |
Acquired Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 392 |
Acquired Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 87 |
Acquired Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 0 |
Acquired Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 1 |
Acquired Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 304 |
Acquired Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 0 |
Acquired Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 403 |
Acquired Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 89 |
Acquired Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 0 |
Acquired Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 0 |
Acquired Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 207 |
Acquired Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 107 |
Acquired Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 257 |
Acquired Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 35 |
Acquired Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 0 |
Acquired Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 1 |
Acquired Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 221 |
Acquired Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 0 |
Acquired Loans [Member] | Nonaccrual Commercial Loans [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 2,333 |
Acquired Loans [Member] | Nonaccrual Commercial Loans [Member] | Loans To Individuals [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 12 |
Acquired Loans [Member] | Nonaccrual Commercial Loans [Member] | Real Estate Construction [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 0 |
Acquired Loans [Member] | Nonaccrual Commercial Loans [Member] | Commercial Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 74 |
Acquired Loans [Member] | Nonaccrual Commercial Loans [Member] | Residential Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | 1,949 |
Acquired Loans [Member] | Nonaccrual Commercial Loans [Member] | Commercial real estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Financing Receivable, Past Due |  | $ 298 |

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