XML 88 R76.htm IDEA: XBRL DOCUMENT v3.5.0.2
Stock Compensation - Assumptions Used in Determination of Grant Date Fair Values Using Black-Scholes Option Pricing Model (Detail)
9 Months Ended
Jun. 30, 2016
Jun. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Document Fiscal Year Focus 2016  
Employee Stock Option [Member] | HGI [Member] | Minimum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Risk-free interest rate 1.65454% 1.57%
Expected option term 5 years 5 years
Volatility 37.38387% 37.10%
Employee Stock Option [Member] | HGI [Member] | Maximum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Risk-free interest rate 1.74249% 1.87%
Expected option term 5 years 6 months 6 years 6 months
Volatility 37.88565% 39.00%
Employee Stock Option [Member] | HGI [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Assumed dividend yield 0.00% 0.00%