XML 82 R48.htm IDEA: XBRL DOCUMENT v3.8.0.1
Cash and Cash Equivalents - Additional Information (Detail) - USD ($)
$ in Thousands
Dec. 31, 2017
Dec. 31, 2016
Cash and Cash Equivalents [Abstract]    
Cash equivalents held at financial institution $ 26,548 $ 55,619
Cash and cash equivalents held at one financial institution $ 24,103 $ 56,484