Debt	6 Months Ended
Jun. 30, 2017
Debt Disclosure [Abstract]
Debt	DEBT On June 21, 2017, we issued $300 million of 3.5% Notes due November 15, 2027 and $300 million of 4.5% Notes due May 15, 2047. We received proceeds of $599 million, net of discount, for the issuance of these Notes. The Notes are senior indebtedness and are redeemable at our option at the applicable redemption price. On June 27, 2017, proceeds from the debt issuances, together with cash on hand, were used to repay and early retire $299 million of our 7.125% Notes due March 15, 2020, $74 million of our 5.95% Notes due March 15, 2022, $62 million of our 7.75% Notes due August 1, 2029, and $100 million of our 6.5% Notes due August 15, 2032. In connection with these early retirements, we incurred a loss on debt extinguishment of $107 million, which was recorded as interest expense. On March 28, 2013, we entered into a credit agreement (the “Credit Agreement”) with a bank group, with an aggregate commitment of $1.25 billion and a maturity date of March 28, 2018. On May 29, 2015 and August 28, 2015, we amended the Credit Agreement with the bank group (the “Amended Credit Agreement”). The Amended Credit Agreement reduced the aggregate commitment to $750 million and extended the maturity date to May 29, 2020. Under the Amended Credit Agreement, at our request and subject to certain conditions, we can increase the aggregate commitment up to an additional $375 million with the current bank group or new lenders. The Amended Credit Agreement provides for an unsecured revolving credit facility available to us and one of our foreign subsidiaries, in U.S. dollars, European Euro and certain other currencies. Borrowings under the revolver denominated in euros are limited to $500 million, equivalent. We can also borrow swingline loans up to $75 million and obtain letters of credit of up to $100 million; any outstanding letters of credit under the Amended Credit Agreement reduce our borrowing capacity. At June 30, 2017, we had no outstanding standby letters of credit under the Amended Credit Agreement. G. DEBT (Concluded) Revolving credit loans bear interest under the Amended Credit Agreement, at our option, at (A) a rate per annum equal to the greatest of (i) the prime rate, (ii) the Federal Funds effective rate plus 0.50% and (iii) LIBOR plus 1.0% (the “Alternative Base Rate”); plus an applicable margin based upon our then-applicable corporate credit ratings; or (B) LIBOR plus an applicable margin based upon our then-applicable corporate credit ratings. The foreign currency revolving credit loans bear interest at a rate equal to LIBOR plus an applicable margin based upon our then-applicable corporate credit ratings. The Amended Credit Agreement contains financial covenants requiring us to maintain (A) a maximum net leverage ratio, as adjusted for certain items, of 4.0 to 1.0, and (B) a minimum interest coverage ratio, as adjusted for certain items, equal to or greater than 2.5 to 1.0. In order for us to borrow under the Amended Credit Agreement, there must not be any default in our covenants in the Amended Credit Agreement (i.e., in addition to the two financial covenants, principally limitations on subsidiary debt, negative pledge restrictions, legal compliance requirements and maintenance of properties and insurance) and our representations and warranties in the Amended Credit Agreement must be true in all material respects on the date of borrowing (i.e., principally no material adverse change or litigation likely to result in a material adverse change, since December 31, 2014, in each case, no material ERISA or environmental non-compliance, and no material tax deficiency). We were in compliance with all covenants and no borrowings have been made at June 30, 2017. Fair Value of Debt. The fair value of our short-term and long-term fixed-rate debt instruments is based principally upon modeled market prices for the same or similar issues, which are Level 1 inputs. The aggregate estimated market value of short-term and long-term debt was approximately $3.4 billion, compared with the aggregate carrying value of $3.1 billion, at June 30, 2017. The aggregate estimated market value of short-term and long-term debt was approximately $3.3 billion, compared with the aggregate carrying value of $3.0 billion, at December 31, 2016.

DEBT

On June 21, 2017, we issued $300 million of 3.5% Notes due November 15, 2027 and $300 million of 4.5% Notes due May 15, 2047. We received proceeds of $599 million, net of discount, for the issuance of these Notes. The Notes are senior indebtedness and are redeemable at our option at the applicable redemption price. On June 27, 2017, proceeds from the debt issuances, together with cash on hand, were used to repay and early retire $299 million of our 7.125% Notes due March 15, 2020, $74 million of our 5.95% Notes due March 15, 2022, $62 million of our 7.75% Notes due August 1, 2029, and $100 million of our 6.5% Notes due August 15, 2032. In connection with these early retirements, we incurred a loss on debt extinguishment of $107 million, which was recorded as interest expense.

On March 28, 2013, we entered into a credit agreement (the “Credit Agreement”) with a bank group, with an aggregate commitment of $1.25 billion and a maturity date of March 28, 2018. On May 29, 2015 and August 28, 2015, we amended the Credit Agreement with the bank group (the “Amended Credit Agreement”). The Amended Credit Agreement reduced the aggregate commitment to $750 million and extended the maturity date to May 29, 2020. Under the Amended Credit Agreement, at our request and subject to certain conditions, we can increase the aggregate commitment up to an additional $375 million with the current bank group or new lenders.

The Amended Credit Agreement provides for an unsecured revolving credit facility available to us and one of our foreign subsidiaries, in U.S. dollars, European Euro and certain other currencies. Borrowings under the revolver denominated in euros are limited to $500 million, equivalent. We can also borrow swingline loans up to $75 million and obtain letters of credit of up to $100 million; any outstanding letters of credit under the Amended Credit Agreement reduce our borrowing capacity. At June 30, 2017, we had no outstanding standby letters of credit under the Amended Credit Agreement.

G. DEBT (Concluded)

Revolving credit loans bear interest under the Amended Credit Agreement, at our option, at (A) a rate per annum equal to the greatest of (i) the prime rate, (ii) the Federal Funds effective rate plus 0.50% and (iii) LIBOR plus 1.0% (the “Alternative Base Rate”); plus an applicable margin based upon our then-applicable corporate credit ratings; or (B) LIBOR plus an applicable margin based upon our then-applicable corporate credit ratings. The foreign currency revolving credit loans bear interest at a rate equal to LIBOR plus an applicable margin based upon our then-applicable corporate credit ratings.

The Amended Credit Agreement contains financial covenants requiring us to maintain (A) a maximum net leverage ratio, as adjusted for certain items, of 4.0 to 1.0, and (B) a minimum interest coverage ratio, as adjusted for certain items, equal to or greater than 2.5 to 1.0.

In order for us to borrow under the Amended Credit Agreement, there must not be any default in our covenants in the Amended Credit Agreement (i.e., in addition to the two financial covenants, principally limitations on subsidiary debt, negative pledge restrictions, legal compliance requirements and maintenance of properties and insurance) and our representations and warranties in the Amended Credit Agreement must be true in all material respects on the date of borrowing (i.e., principally no material adverse change or litigation likely to result in a material adverse change, since December 31, 2014, in each case, no material ERISA or environmental non-compliance, and no material tax deficiency). We were in compliance with all covenants and no borrowings have been made at June 30, 2017.

Fair Value of Debt. The fair value of our short-term and long-term fixed-rate debt instruments is based principally upon modeled market prices for the same or similar issues, which are Level 1 inputs. The aggregate estimated market value of short-term and long-term debt was approximately $3.4 billion, compared with the aggregate carrying value of $3.1 billion, at June 30, 2017. The aggregate estimated market value of short-term and long-term debt was approximately $3.3 billion, compared with the aggregate carrying value of $3.0 billion, at December 31, 2016.