Legal Matters - Additional Information (Detail) $ in Millions	Aug. 05, 2015 USD ($) Plaintiff Employee
Robles Lawsuits [Member]
Loss Contingencies [Line Items]
Number of plaintiffs against HGT | Plaintiff	63
Number of employees filed lawsuit | Employee	5
Robles And Adame Lawsuits | Accrued Other [Member]
Loss Contingencies [Line Items]
Claims settlement recorded in consolidated balance sheet	$ 4.8
Robles And Adame Lawsuits | General and Administrative Expense
Loss Contingencies [Line Items]
Claims settlement recorded in consolidated statement of income and comprehensive income	$ 4.8