Quarterly report pursuant to Section 13 or 15(d)

Debt - Interest Rate Swap Contracts as Reflected on Balance Sheet (Details)

v3.10.0.1
Debt - Interest Rate Swap Contracts as Reflected on Balance Sheet (Details) - Designated as Hedging Instrument - Interest Rate Swaps - USD ($)
$ in Thousands
Jun. 30, 2018
Sep. 30, 2017
Derivatives, Fair Value [Line Items]    
Total derivatives $ 10,863 $ 3,959
Current assets: Other Current Assets    
Derivatives, Fair Value [Line Items]    
Assets derivatives 3,489 1,098
Long-term assets: Other Assets    
Derivatives, Fair Value [Line Items]    
Assets derivatives 7,374 2,892
Current Liabilities: Other Current Liabilities    
Derivatives, Fair Value [Line Items]    
Liability derivatives 0 (7)
Long-Term Liabilities: Other Liabilities    
Derivatives, Fair Value [Line Items]    
Liability derivatives $ 0 $ (24)