Income Taxes (Details)	3 Months Ended		9 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Taxes
Effective income tax rate (as a percent)	(15.50%)	30.20%	62.90%	35.20%
Effective income tax rates as compared to the U.S. Federal income tax rate
U.S. federal statutory rate (as a percent)			35.00%