New Accounting Standards - Narrative (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Jun. 30, 2015	Sep. 30, 2014
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Debt issuance cost	$ 18	$ 17

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

No definition available.