Intangible Assets Intangible Asset Additions (Details) $ in Millions	12 Months Ended
Sep. 30, 2017 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-lived Intangible Assets Acquired	$ 6.0

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

No definition available.

Name:	us-gaap_FinitelivedIntangibleAssetsAcquired1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration