Debt (Notes)	3 Months Ended
Mar. 31, 2018
Debt Disclosure [Abstract]
Debt	Debt Revolving Credit Facility As of March 31, 2018, we had no borrowings against our $3.4 billion revolving credit facility (the “Credit Facility”), as described below. The Credit Facility includes a covenant requiring that our ratio of total debt to total capitalization not exceed 65% as of the last day of each fiscal quarter. If an event of default occurs, the lenders holding more than half of the commitments may terminate the commitments under the Credit Facility and require the immediate repayment of all outstanding borrowings and the cash collateralization of all outstanding letters of credit under the Credit Facility. As of March 31, 2018, we were in compliance with this covenant with a debt-to-capitalization ratio of 31%. Long-term debt As of March 31, 2018 we had $5.5 billion in long-term debt outstanding, with our next debt maturity in the amount of $600 million due in 2020.

Debt (Notes)

3 Months Ended

Mar. 31, 2018

Revolving Credit Facility

As of March 31, 2018, we had no borrowings against our $3.4 billion revolving credit facility (the “Credit Facility”), as described below.

The Credit Facility includes a covenant requiring that our ratio of total debt to total capitalization not exceed 65% as of the last day of each fiscal quarter. If an event of default occurs, the lenders holding more than half of the commitments may terminate the commitments under the Credit Facility and require the immediate repayment of all outstanding borrowings and the cash collateralization of all outstanding letters of credit under the Credit Facility. As of March 31, 2018, we were in compliance with this covenant with a debt-to-capitalization ratio of 31%.

Long-term debt

As of March 31, 2018 we had $5.5 billion in long-term debt outstanding, with our next debt maturity in the amount of $600 million due in 2020.