Quarterly report pursuant to Section 13 or 15(d)

Goodwill - Summary of Changes to Carrying Amount of Goodwill (Detail)

v3.19.2
Goodwill - Summary of Changes to Carrying Amount of Goodwill (Detail) - USD ($)
$ in Thousands
6 Months Ended 12 Months Ended
Jun. 30, 2019
Dec. 31, 2018
Goodwill [Line Items]    
Beginning, Gross balance $ 42,583 $ 42,583
Beginning, Accumulated impairment losses (17,415) (17,415)
Beginning, Net balance 25,168 25,168
Ending, Gross balance 44,767 42,583
Ending, Accumulated impairment losses (17,415) (17,415)
Ending, Net balance 27,352 25,168
Neosho    
Goodwill [Line Items]    
Goodwill, Acquisition $ 2,184 $ 0