Employee Benefit Plans - Defined Benefit Pension Plans Weighted-Average Asset Allocations (Detail)	Sep. 30, 2016	Sep. 30, 2015
U.S. Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities	50.00%	55.00%
Debt securities	50.00%	45.00%
Total	100.00%	100.00%
Foreign Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities	39.00%	39.00%
Debt securities	53.00%	54.00%
Cash and other securities	8.00%	7.00%
Total	100.00%	100.00%