Recent Accounting Pronouncements - Additional Information (Detail) - USD ($) |
3 Months Ended | 6 Months Ended | |
|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2019 |
Jan. 01, 2019 |
|
| New Accounting Pronouncements Or Change In Accounting Principle [Line Items] | |||
| Initial right-of-use assets | $ 4,179,000 | $ 4,179,000 | |
| Operating lease, expense | $ 305,000 | $ 653,000 | |
| ASU 2016 02 [Member] | |||
| New Accounting Pronouncements Or Change In Accounting Principle [Line Items] | |||
| Initial right-of-use assets | $ 4,642,000 |