Employee Retirement Plans - Actuarial Assumptions for Domestic Plans (Details)	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Pension Benefit
Weighted-average assumption:
Discount rate - benefit obligations	4.60%	5.20%	4.20%
Discount rate - benefit cost	5.20%	4.20%	5.30%
Expected return on plan assets	7.75%	7.75%	7.75%
Rate of increase in salary levels	3.25%	3.25%	3.25%
Other Postretirement Benefits
Weighted-average assumption:
Discount rate - benefit obligations	4.60%
Discount rate - benefit cost			5.30%
Expected return on plan assets	5.00%	5.00%	5.20%
Rate of increase in salary levels	3.25%	3.25%	3.25%
Minimum | Other Postretirement Benefits
Weighted-average assumption:
Discount rate - benefit obligations		5.10%	4.10%
Discount rate - benefit cost	5.10%	4.10%
Maximum | Other Postretirement Benefits
Weighted-average assumption:
Discount rate - benefit obligations		5.40%	4.30%
Discount rate - benefit cost	5.40%	4.30%