Short-Term Borrowings, Long-Term Debt and Available Credit Facilities Uncommitted Credit Facilities and Outstanding Letters of Credit (Details) $ in Millions	Sep. 30, 2019 USD ($)
Debt Disclosure [Abstract]
Unused bank credit lines on uncommitted credit facilities	$ 401
Letters of Credit Outstanding, Amount	$ 100

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant