Loans and the Allowance for Credit Losses - Summary of Changes in Allowance for Credit Losses (Detail) - USD ($)
$ in Thousands |
3 Months Ended |
Mar. 31, 2018 |
Mar. 31, 2017 |
| Financing Receivable, Allowance for Credit Losses [Line Items] |
|
|
| Allowance for loan losses, beginning balance |
$ 45,284
|
$ 43,674
|
| Allowance for loan commitments, beginning balance |
574
|
571
|
| Total beginning allowance for credit losses |
45,858
|
44,245
|
| Provision for loan losses |
2,113
|
2,734
|
| Provision for loan commitments |
55
|
(23)
|
| Total provision for credit losses |
2,168
|
2,711
|
| Charge-offs |
(2,643)
|
(3,619)
|
| Recoveries |
1,580
|
1,272
|
| Net charge-offs |
(1,063)
|
(2,347)
|
| Allowance for loan losses, ending balance |
46,334
|
44,061
|
| Allowance for loan commitments, ending balance |
629
|
548
|
| Total ending allowance for credit losses |
46,963
|
44,609
|
| Commercial Real Estate - Land and Construction [Member] |
|
|
| Financing Receivable, Allowance for Credit Losses [Line Items] |
|
|
| Allowance for loan losses, beginning balance |
3,117
|
4,348
|
| Allowance for loan commitments, beginning balance |
119
|
151
|
| Total beginning allowance for credit losses |
3,236
|
4,499
|
| Provision for loan losses |
1,090
|
(425)
|
| Provision for loan commitments |
57
|
(8)
|
| Total provision for credit losses |
1,147
|
(433)
|
| Recoveries |
117
|
52
|
| Net charge-offs |
117
|
52
|
| Allowance for loan losses, ending balance |
4,324
|
3,975
|
| Allowance for loan commitments, ending balance |
176
|
143
|
| Total ending allowance for credit losses |
4,500
|
4,118
|
| Commercial Real Estate - Improved Property [Member] |
|
|
| Financing Receivable, Allowance for Credit Losses [Line Items] |
|
|
| Allowance for loan losses, beginning balance |
21,166
|
18,628
|
| Allowance for loan commitments, beginning balance |
26
|
17
|
| Total beginning allowance for credit losses |
21,192
|
18,645
|
| Provision for loan losses |
(895)
|
983
|
| Provision for loan commitments |
(5)
|
|
| Total provision for credit losses |
(900)
|
983
|
| Charge-offs |
(279)
|
(602)
|
| Recoveries |
287
|
251
|
| Net charge-offs |
8
|
(351)
|
| Allowance for loan losses, ending balance |
20,279
|
19,260
|
| Allowance for loan commitments, ending balance |
21
|
17
|
| Total ending allowance for credit losses |
20,300
|
19,277
|
| Commercial and Industrial [Member] |
|
|
| Financing Receivable, Allowance for Credit Losses [Line Items] |
|
|
| Allowance for loan losses, beginning balance |
9,414
|
8,412
|
| Allowance for loan commitments, beginning balance |
173
|
188
|
| Total beginning allowance for credit losses |
9,587
|
8,600
|
| Provision for loan losses |
919
|
832
|
| Provision for loan commitments |
3
|
(31)
|
| Total provision for credit losses |
922
|
801
|
| Charge-offs |
(109)
|
(880)
|
| Recoveries |
270
|
376
|
| Net charge-offs |
161
|
(504)
|
| Allowance for loan losses, ending balance |
10,494
|
8,740
|
| Allowance for loan commitments, ending balance |
176
|
157
|
| Total ending allowance for credit losses |
10,670
|
8,897
|
| Deposit Overdraft [Member] |
|
|
| Financing Receivable, Allowance for Credit Losses [Line Items] |
|
|
| Allowance for loan losses, beginning balance |
821
|
760
|
| Total beginning allowance for credit losses |
821
|
760
|
| Provision for loan losses |
(48)
|
66
|
| Total provision for credit losses |
(48)
|
66
|
| Charge-offs |
(267)
|
(338)
|
| Recoveries |
109
|
98
|
| Net charge-offs |
(158)
|
(240)
|
| Allowance for loan losses, ending balance |
615
|
586
|
| Total ending allowance for credit losses |
615
|
586
|
| Residential Real Estate [Member] |
|
|
| Financing Receivable, Allowance for Credit Losses [Line Items] |
|
|
| Allowance for loan losses, beginning balance |
3,206
|
4,106
|
| Allowance for loan commitments, beginning balance |
7
|
9
|
| Total beginning allowance for credit losses |
3,213
|
4,115
|
| Provision for loan losses |
202
|
330
|
| Provision for loan commitments |
|
1
|
| Total provision for credit losses |
202
|
331
|
| Charge-offs |
(287)
|
(404)
|
| Recoveries |
131
|
78
|
| Net charge-offs |
(156)
|
(326)
|
| Allowance for loan losses, ending balance |
3,252
|
4,110
|
| Allowance for loan commitments, ending balance |
7
|
10
|
| Total ending allowance for credit losses |
3,259
|
4,120
|
| Consumer [Member] |
|
|
| Financing Receivable, Allowance for Credit Losses [Line Items] |
|
|
| Allowance for loan losses, beginning balance |
3,063
|
3,998
|
| Allowance for loan commitments, beginning balance |
37
|
44
|
| Total beginning allowance for credit losses |
3,100
|
4,042
|
| Provision for loan losses |
583
|
583
|
| Provision for loan commitments |
4
|
(2)
|
| Total provision for credit losses |
587
|
581
|
| Charge-offs |
(1,125)
|
(1,287)
|
| Recoveries |
546
|
369
|
| Net charge-offs |
(579)
|
(918)
|
| Allowance for loan losses, ending balance |
3,067
|
3,663
|
| Allowance for loan commitments, ending balance |
41
|
42
|
| Total ending allowance for credit losses |
3,108
|
3,705
|
| Home Equity [Member] |
|
|
| Financing Receivable, Allowance for Credit Losses [Line Items] |
|
|
| Allowance for loan losses, beginning balance |
4,497
|
3,422
|
| Allowance for loan commitments, beginning balance |
212
|
162
|
| Total beginning allowance for credit losses |
4,709
|
3,584
|
| Provision for loan losses |
262
|
365
|
| Provision for loan commitments |
(4)
|
17
|
| Total provision for credit losses |
258
|
382
|
| Charge-offs |
(576)
|
(108)
|
| Recoveries |
120
|
48
|
| Net charge-offs |
(456)
|
(60)
|
| Allowance for loan losses, ending balance |
4,303
|
3,727
|
| Allowance for loan commitments, ending balance |
208
|
179
|
| Total ending allowance for credit losses |
$ 4,511
|
$ 3,906
|