Annual report pursuant to Section 13 and 15(d)

Consolidating Condensed Financial Information of Guarantor Subsidiaries - Additional Information (Detail)

v3.8.0.1
Consolidating Condensed Financial Information of Guarantor Subsidiaries - Additional Information (Detail)
12 Months Ended
Sep. 30, 2017
Guarantor Subsidiaries  
Condensed Financial Statements, Captions [Line Items]  
Collective ownership percentage on guarantor subsidiaries 100.00%