Fair Value Measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Sep. 30, 2016
Liabilities
Unamortized debt issuance costs	$ 16,390	$ 18,113
Fair value measurement on recurring basis | Total
Assets
Total assets	25
Liabilities
Long-term debt (b)	1,922,179	1,899,748
Total liabilities	1,923,700	1,900,020
Foreign exchange contracts | Fair value measurement on recurring basis | Total
Assets
Foreign exchange contracts (a)	25
Liabilities
Foreign exchange contracts (a)	1,521	272
Level 1 | Fair value measurement on recurring basis
Liabilities
Long-term debt (b)	1,839,063	1,897,625
Total liabilities	1,839,063	1,897,625
Level 2 | Fair value measurement on recurring basis
Assets
Total assets	25
Liabilities
Long-term debt (b)	83,116	2,123
Total liabilities	84,637	2,395
Level 2 | Foreign exchange contracts | Fair value measurement on recurring basis
Assets
Foreign exchange contracts (a)	25
Liabilities
Foreign exchange contracts (a)	1,521	272
ABL facility
Liabilities
Long-term debt (b)	1,888,000	1,807,700
Unamortized debt issuance costs	$ 21,200	$ 23,700