Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands |
9 Months Ended | |
|---|---|---|
|
Sep. 30, 2016
USD ($)
State
Branch
Segment
|
Dec. 31, 2015
USD ($)
|
|
| Summary Of Significant Accounting Policies [Line Items] | ||
| Assets managed by the Company | $ 767,000 | |
| Assets | $ 2,450,273 | $ 2,462,276 |
| Number of business segment | Segment | 1 | |
| First Community Bank | ||
| Summary Of Significant Accounting Policies [Line Items] | ||
| Number of operating branches | Branch | 45 | |
| Number of states the company provides services | State | 4 |