Subsequent Event	6 Months Ended
Jun. 30, 2021
Subsequent Events [Abstract]
Subsequent Event	Subsequent Event On July 28, 2021, we entered into a $650 million, 5-year Revolving Credit Agreement (the “2021 Facility”), which replaced the existing $550 million revolving credit facility. The 2021 Facility allows us to borrow, repay, or to the extent permitted by the agreement, prepay and re-borrow funds at any time prior to the stated maturity date. Interest on loans made under the 2021 Facility accrues, at our option, at a rate per annum equal to (1) a base rate, plus a margin ranging from 0.00% to 0.50% depending upon the ratings by S&P and Moody’s of our senior unsecured long-term debt (the "Index Debt Rating"), or (2) an adjusted LIBO rate or the applicable replacement rate (determined based on “hardwired” LIBOR transition provisions consistent with those published by the Alternative References Rates Committee) for an interest period to be selected by us, plus a margin ranging from 0.805% to 1.50% depending upon the Index Debt Rating. The 2021 Facility contains customary affirmative and negative covenants for credit facilities of this type, including limitations on us and our subsidiaries with respect to indebtedness, liens, mergers, consolidations, liquidations and dissolutions, sales of all or substantially all assets, transactions with affiliates and hedging arrangements. We must also maintain a debt to capitalization ratio not to exceed 0.65 to 1.00 at all times. The 2021 Facility also provides for customary events of default, including failure to pay principal, interest or fees when due, failure to comply with covenants, any representation or warranty made by us or any of our material subsidiaries being false in any material respect, default under certain other material indebtedness, certain insolvency or receivership events affecting us and our material subsidiaries, certain ERISA events, material judgments and a change in control of us. On July 28, 2021, we increased the size of the CP Program to permit the issuance of short-term, unsecured commercial paper notes in an aggregate principal amount not to exceed $650 million at any time outstanding. Prior to this increase, the CP Program permitted us to issue commercial paper notes in an aggregate principal amount not to exceed $550 million at any time outstanding. The other terms and conditions of the CP program remain the same. Amounts available under the CP Program may be borrowed, repaid and re-borrowed from time to time. The notes will have maturities of up to 397 days from date of issue.

Subsequent Event

6 Months Ended

Jun. 30, 2021

Subsequent Event On July 28, 2021, we entered into a $650 million, 5-year Revolving Credit Agreement (the “2021 Facility”), which replaced the existing $550 million revolving credit facility. The 2021 Facility allows us to borrow, repay, or to the extent permitted by the agreement, prepay and re-borrow funds at any time prior to the stated maturity date. Interest on loans made under the 2021 Facility accrues, at our option, at a rate per annum equal to (1) a base rate, plus a margin ranging from 0.00% to 0.50% depending upon the ratings by S&P and Moody’s of our senior unsecured long-term debt (the "Index Debt Rating"), or (2) an adjusted LIBO rate or the applicable replacement rate (determined based on “hardwired” LIBOR transition provisions consistent with those published by the Alternative References Rates Committee) for an interest period to be selected by us, plus a margin ranging from 0.805% to 1.50% depending upon the Index Debt Rating. The 2021 Facility contains customary affirmative and negative covenants for credit facilities of this type, including limitations on us and our subsidiaries with respect to indebtedness, liens, mergers, consolidations, liquidations and dissolutions, sales of all or substantially all assets, transactions with affiliates and hedging arrangements. We must also maintain a debt to capitalization ratio not to exceed 0.65 to 1.00 at all times. The 2021 Facility also provides for customary events of default, including failure to pay principal, interest or fees when due, failure to comply with covenants, any representation or warranty made by us or any of our material subsidiaries being false in any material respect, default under certain other material indebtedness, certain insolvency or receivership events affecting us and our material subsidiaries, certain ERISA events, material judgments and a change in control of us. On July 28, 2021, we increased the size of the CP Program to permit the issuance of short-term, unsecured commercial paper notes in an aggregate principal amount not to exceed $650 million at any time outstanding. Prior to this increase, the CP Program permitted us to issue commercial paper notes in an aggregate principal amount not to exceed $550 million at any time outstanding. The other terms and conditions of the CP program remain the same. Amounts available under the CP Program may be borrowed, repaid and re-borrowed from time to time. The notes will have maturities of up to 397 days from date of issue.