Summary of Loans (Detail) - USD ($)
$ in Thousands |
Sep. 30, 2016 |
Jun. 30, 2016 |
Dec. 31, 2015 |
Sep. 30, 2015 |
Jun. 30, 2015 |
Dec. 31, 2014 |
| Accounts, Notes, Loans and Financing Receivable [Line Items] |
|
|
|
|
|
|
|
| Total Loans Balance |
|
$ 1,789,417
|
|
$ 1,537,189
|
|
|
|
| Net deferred loan costs |
|
3,814
|
|
4,663
|
|
|
|
| Net unamortized mortgage premiums |
|
6,100
|
|
4,345
|
|
|
|
| Allowance for loan losses |
|
(12,969)
|
$ (12,543)
|
(11,240)
|
$ (10,390)
|
$ (9,537)
|
$ (8,881)
|
| Total loans, net |
|
$ 1,786,362
|
|
$ 1,534,957
|
|
|
|
| Commercial and consumer gross percent |
|
7.35%
|
|
10.25%
|
|
|
|
| Total loans, Percent |
|
100.00%
|
|
100.00%
|
|
|
|
| Mortgage Loan Portfolio Segment |
|
|
|
|
|
|
|
| Accounts, Notes, Loans and Financing Receivable [Line Items] |
|
|
|
|
|
|
|
| Total Loans Balance |
|
$ 1,657,805
|
|
$ 1,379,579
|
|
|
|
| Mortgage loans on real estate percent |
|
92.65%
|
|
89.75%
|
|
|
|
| Mortgage Loan Portfolio Segment | Real Estate Loan | Residential one-to-four family |
|
|
|
|
|
|
|
| Accounts, Notes, Loans and Financing Receivable [Line Items] |
|
|
|
|
|
|
|
| Total Loans Balance |
|
$ 947,667
|
|
$ 709,426
|
|
|
|
| Mortgage loans on real estate percent |
|
52.96%
|
|
46.15%
|
|
|
|
| Allowance for loan losses |
|
$ (4,594)
|
(4,155)
|
$ (3,574)
|
(3,303)
|
(2,740)
|
(2,364)
|
| Mortgage Loan Portfolio Segment | Real Estate Loan | Commercial real estate loans |
|
|
|
|
|
|
|
| Accounts, Notes, Loans and Financing Receivable [Line Items] |
|
|
|
|
|
|
|
| Total Loans Balance |
[1] |
$ 462,600
|
|
$ 449,391
|
|
|
|
| Mortgage loans on real estate percent |
[1] |
25.85%
|
|
29.24%
|
|
|
|
| Allowance for loan losses |
|
$ (4,639)
|
(4,810)
|
$ (4,478)
|
(4,136)
|
(4,122)
|
(4,043)
|
| Mortgage Loan Portfolio Segment | Home equity lines of credit |
|
|
|
|
|
|
|
| Accounts, Notes, Loans and Financing Receivable [Line Items] |
|
|
|
|
|
|
|
| Total Loans Balance |
|
$ 170,857
|
|
$ 160,040
|
|
|
|
| Mortgage loans on real estate percent |
|
9.55%
|
|
10.41%
|
|
|
|
| Allowance for loan losses |
|
$ (1,041)
|
(1,038)
|
$ (928)
|
(830)
|
(827)
|
(828)
|
| Mortgage Loan Portfolio Segment | Construction loans |
|
|
|
|
|
|
|
| Accounts, Notes, Loans and Financing Receivable [Line Items] |
|
|
|
|
|
|
|
| Total Loans Balance |
|
$ 76,681
|
|
$ 60,722
|
|
|
|
| Mortgage loans on real estate percent |
|
4.29%
|
|
3.95%
|
|
|
|
| Allowance for loan losses |
|
$ (1,051)
|
(864)
|
$ (801)
|
(833)
|
(585)
|
(228)
|
| Commercial Portfolio Segment |
|
|
|
|
|
|
|
| Accounts, Notes, Loans and Financing Receivable [Line Items] |
|
|
|
|
|
|
|
| Total Loans Balance |
|
61,314
|
|
53,192
|
|
|
|
| Allowance for loan losses |
|
$ (710)
|
(698)
|
$ (613)
|
(423)
|
(355)
|
(458)
|
| Commercial loans, percentage |
|
3.43%
|
|
3.46%
|
|
|
|
| Consumer Portfolio Segment | Indirect auto loans |
|
|
|
|
|
|
|
| Accounts, Notes, Loans and Financing Receivable [Line Items] |
|
|
|
|
|
|
|
| Total Loans Balance |
|
$ 69,865
|
|
$ 103,965
|
|
|
|
| consumer loans, percent |
|
3.90%
|
|
6.76%
|
|
|
|
| Allowance for loan losses |
|
$ (433)
|
(492)
|
$ (623)
|
(652)
|
(713)
|
(778)
|
| Consumer Portfolio Segment | Other Consumer Loan |
|
|
|
|
|
|
|
| Accounts, Notes, Loans and Financing Receivable [Line Items] |
|
|
|
|
|
|
|
| Total Loans Balance |
|
$ 433
|
|
$ 453
|
|
|
|
| consumer loans, percent |
|
0.02%
|
|
0.03%
|
|
|
|
| Allowance for loan losses |
|
$ (9)
|
$ (10)
|
$ (10)
|
$ (13)
|
$ (12)
|
$ (11)
|
| Commercial and Consumer Loan |
|
|
|
|
|
|
|
| Accounts, Notes, Loans and Financing Receivable [Line Items] |
|
|
|
|
|
|
|
| Total Loans Balance |
|
$ 131,612
|
|
$ 157,610
|
|
|
|
|
|