Derivatives - Narrative (Details) $ in Millions	3 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2016 swap
Derivative Instruments, Gain (Loss) [Line Items]
Number of new derivatives | swap		0
Predecessor
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instruments	$ 0.1
Predecessor | Interest Rate Swap | Other comprehensive income | Designated as Hedging Instrument | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instruments	0.1
Predecessor | Interest Rate Swap | Interest expense | Designated as Hedging Instrument | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instruments	$ (0.2)