XML 108 R71.htm IDEA: XBRL DOCUMENT v3.19.1
Accounts receivable and other - Summary of Accounts Receivable and Other (Detail) - USD ($)
$ in Thousands
Dec. 31, 2018
Dec. 31, 2017
Trade and other current receivables [abstract]    
Trade receivables $ 22,072 $ 7,746
Value added tax and other taxes recoverable 34,791 44,717
Other receivables and advances 8,378 7,134
Prepaid expenses and deposits 15,746 18,747
Accounts receivable and other $ 80,987 $ 78,344