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Loans and Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2017
Allowance for loan losses: |  |  |  |  |
Beginning balance | $ 15,813 | $ 15,232 | $ 15,767 | $ 15,442 |
Provision for loan losses | 0 | 0 | 0 | 0 |
Charge-offs | 0 | (6) | (5) | (292) |
Recoveries | 4 | 22 | 55 | 98 |
Ending balance | 15,817 | 15,248 | 15,817 | 15,248 |
Ending ALLL related to loans collectively evaluated for impairment | 15,290 |  | 15,290 |  | $ 15,254
Ending ALLL related to loans individually evaluated for impairment | 527 |  | 527 |  | 513
Ending ALLL | 15,817 |  | 15,817 |  | 15,767
Collectively evaluated for impairment | 1,711,211 |  | 1,711,211 |  | 1,659,972
Individually evaluated for impairment | 15,531 |  | 15,531 |  | 16,926
Total loans | $ 1,728,871 |  | $ 1,728,871 |  | $ 1,679,013
Ratio of allowance for loan losses to total loans | 0.91% |  | 0.91% |  | 0.94%
Allowance for loan losses to non-accrual loans | 4098.00% |  | 4098.00% |  | 3883.00%
Purchased credit-impaired |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Ending ALLL | $ 0 |  | $ 0 |  | $ 0
Purchased credit-impaired | 2,129 |  | 2,129 |  | 2,115
Commercial loans | Commercial and industrial |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Beginning balance | 2,597 | 3,932 | 3,654 | 3,248 |
Provision for loan losses | (245) | 612 | (1,308) | 1,509 |
Charge-offs | 0 | (5) | (3) | (289) |
Recoveries | 4 | 21 | 13 | 92 |
Ending balance | 2,356 | 4,560 | 2,356 | 4,560 |
Ending ALLL related to loans collectively evaluated for impairment | 2,183 |  | 2,183 |  | 3,604
Ending ALLL related to loans individually evaluated for impairment | 173 |  | 173 |  | 50
Ending ALLL | 2,356 |  | 2,356 |  | 3,654
Collectively evaluated for impairment | 236,969 |  | 236,969 |  | 233,605
Individually evaluated for impairment | 1,763 |  | 1,763 |  | 2,165
Total loans | $ 238,771 |  | $ 238,771 |  | $ 235,835
Ratio of allowance for loan losses to total loans | 0.99% |  | 0.99% |  | 1.55%
Commercial loans | Commercial and industrial | Purchased credit-impaired |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Ending ALLL | $ 0 |  | $ 0 |  | $ 0
Purchased credit-impaired | 39 |  | 39 |  | 65
Commercial real estate loans | Commercial real estate, owner-occupied |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Beginning balance | 2,339 | 2,082 | 2,294 | 1,753 |
Provision for loan losses | 83 | (56) | 128 | 273 |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 0 | 0 | 0 |
Ending balance | 2,422 | 2,026 | 2,422 | 2,026 |
Ending ALLL related to loans collectively evaluated for impairment | 2,194 |  | 2,194 |  | 2,106
Ending ALLL related to loans individually evaluated for impairment | 228 |  | 228 |  | 188
Ending ALLL | 2,422 |  | 2,422 |  | 2,294
Collectively evaluated for impairment | 308,272 |  | 308,272 |  | 292,798
Individually evaluated for impairment | 6,997 |  | 6,997 |  | 6,999
Total loans | $ 316,467 |  | $ 316,467 |  | $ 300,963
Ratio of allowance for loan losses to total loans | 0.77% |  | 0.77% |  | 0.76%
Commercial real estate loans | Commercial real estate, owner-occupied | Purchased credit-impaired |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Ending ALLL | $ 0 |  | $ 0 |  | $ 0
Purchased credit-impaired | 1,198 |  | 1,198 |  | 1,166
Commercial real estate loans | Commercial real estate, investor |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Beginning balance | 7,390 | 6,065 | 6,475 | 6,320 |
Provision for loan losses | 46 | 33 | 961 | (222) |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 0 | 0 | 0 |
Ending balance | 7,436 | 6,098 | 7,436 | 6,098 |
Ending ALLL related to loans collectively evaluated for impairment | 7,392 |  | 7,392 |  | 6,316
Ending ALLL related to loans individually evaluated for impairment | 44 |  | 44 |  | 159
Ending ALLL | 7,436 |  | 7,436 |  | 6,475
Collectively evaluated for impairment | 838,856 |  | 838,856 |  | 820,023
Individually evaluated for impairment | 1,831 |  | 1,831 |  | 2,171
Total loans | $ 841,493 |  | $ 841,493 |  | $ 822,984
Ratio of allowance for loan losses to total loans | 0.88% |  | 0.88% |  | 0.79%
Commercial real estate loans | Commercial real estate, investor | Purchased credit-impaired |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Ending ALLL | $ 0 |  | $ 0 |  | $ 0
Purchased credit-impaired | 806 |  | 806 |  | 790
Commercial real estate loans | Construction |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Beginning balance | 508 | 411 | 681 | 781 |
Provision for loan losses | 157 | 217 | (16) | (153) |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 0 | 0 | 0 |
Ending balance | 665 | 628 | 665 | 628 |
Ending ALLL related to loans collectively evaluated for impairment | 665 |  | 665 |  | 674
Ending ALLL related to loans individually evaluated for impairment | 0 |  | 0 |  | 7
Ending ALLL | 665 |  | 665 |  | 681
Collectively evaluated for impairment | 66,049 |  | 66,049 |  | 60,859
Individually evaluated for impairment | 2,690 |  | 2,690 |  | 2,969
Total loans | $ 68,739 |  | $ 68,739 |  | $ 63,828
Ratio of allowance for loan losses to total loans | 0.97% |  | 0.97% |  | 1.07%
Commercial real estate loans | Construction | Purchased credit-impaired |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Ending ALLL | $ 0 |  | $ 0 |  | $ 0
Purchased credit-impaired | 0 |  | 0 |  | 0
Residential loans | Home equity |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Beginning balance | 952 | 981 | 1,031 | 973 |
Provision for loan losses | (39) | 21 | (118) | 29 |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 0 | 0 | 0 |
Ending balance | 913 | 1,002 | 913 | 1,002 |
Ending ALLL related to loans collectively evaluated for impairment | 908 |  | 908 |  | 1,025
Ending ALLL related to loans individually evaluated for impairment | 5 |  | 5 |  | 6
Ending ALLL | 913 |  | 913 |  | 1,031
Collectively evaluated for impairment | 120,588 |  | 120,588 |  | 131,620
Individually evaluated for impairment | 569 |  | 569 |  | 753
Total loans | $ 121,243 |  | $ 121,243 |  | $ 132,467
Ratio of allowance for loan losses to total loans | 0.75% |  | 0.75% |  | 0.78%
Allowance for loan losses to non-accrual loans | 287.00% |  | 287.00% |  | 254.00%
Residential loans | Home equity | Purchased credit-impaired |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Ending ALLL | $ 0 |  | $ 0 |  | $ 0
Purchased credit-impaired | 86 |  | 86 |  | 94
Residential loans | Other residential |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Beginning balance | 746 | 509 | 536 | 454 |
Provision for loan losses | 35 | 33 | 245 | 88 |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 0 | 0 | 0 |
Ending balance | 781 | 542 | 781 | 542 |
Ending ALLL related to loans collectively evaluated for impairment | 781 |  | 781 |  | 535
Ending ALLL related to loans individually evaluated for impairment | 0 |  | 0 |  | 1
Ending ALLL | 781 |  | 781 |  | 536
Collectively evaluated for impairment | 112,397 |  | 112,397 |  | 94,378
Individually evaluated for impairment | 986 |  | 986 |  | 1,148
Total loans | $ 113,383 |  | $ 113,383 |  | $ 95,526
Ratio of allowance for loan losses to total loans | 0.69% |  | 0.69% |  | 0.56%
Residential loans | Other residential | Purchased credit-impaired |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Ending ALLL | $ 0 |  | $ 0 |  | $ 0
Purchased credit-impaired | 0 |  | 0 |  | 0
Consumer loans | Installment and other consumer |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Beginning balance | 325 | 340 | 378 | 372 |
Provision for loan losses | 5 | (5) | (88) | (40) |
Charge-offs | 0 | (1) | (2) | (3) |
Recoveries | 0 | 1 | 42 | 6 |
Ending balance | 330 | 335 | 330 | 335 |
Ending ALLL related to loans collectively evaluated for impairment | 253 |  | 253 |  | 276
Ending ALLL related to loans individually evaluated for impairment | 77 |  | 77 |  | 102
Ending ALLL | 330 |  | 330 |  | 378
Collectively evaluated for impairment | 28,080 |  | 28,080 |  | 26,689
Individually evaluated for impairment | 695 |  | 695 |  | 721
Total loans | $ 28,775 |  | $ 28,775 |  | $ 27,410
Ratio of allowance for loan losses to total loans | 1.15% |  | 1.15% |  | 1.38%
Allowance for loan losses to non-accrual loans | 485.00% |  | 485.00% |  |
Consumer loans | Installment and other consumer | Purchased credit-impaired |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Ending ALLL | $ 0 |  | $ 0 |  | $ 0
Purchased credit-impaired | 0 |  | 0 |  | 0
Unallocated |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Beginning balance | 956 | 912 | 718 | 1,541 |
Provision for loan losses | (42) | (855) | 196 | (1,484) |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 0 | 0 | 0 |
Ending balance | 914 | $ 57 | 914 | $ 57 |
Ending ALLL related to loans collectively evaluated for impairment | 914 |  | 914 |  | 718
Ending ALLL related to loans individually evaluated for impairment | 0 |  | 0 |  | 0
Ending ALLL | 914 |  | 914 |  | 718
Collectively evaluated for impairment | 0 |  | 0 |  | 0
Individually evaluated for impairment | 0 |  | 0 |  | 0
Total loans | 0 |  | 0 |  | 0
Unallocated | Purchased credit-impaired |  |  |  |  |
Allowance for loan losses: |  |  |  |  |
Ending ALLL | 0 |  | 0 |  | 0
Purchased credit-impaired | $ 0 |  | $ 0 |  | $ 0

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