Revolving Credit Facility	3 Months Ended
Mar. 31, 2019
Revolving Credit Facility [Abstract]
Long-term Debt	Revolving Credit Facility On March 5, 2019, we entered into a new $3.5 billion five-year revolving credit facility which replaced our $3.0 billion revolving credit facility established in July 2015. The revolving credit facility is for general working capital purposes and expires on March 5, 2024. The full amount of the revolving credit facility was available as of March 31, 2019.

The entire disclosure for long-term debt.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-URI http://asc.fasb.org/topic&trid=2208564

Name:	us-gaap_LongTermDebtTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration