Debt

The Company’s outstanding debt is as follows:



(In millions)	March 31, 2018		December 31, 2017
Short-term:
Commercial paper	$	249	$	—
Current portion of long-term debt	263		262
	512		262
Long-term:
Senior notes – 2.55% due 2018	250		250
Senior notes – 2.35% due 2019	299		299
Senior notes – 2.35% due 2020	498		498
Senior notes – 4.80% due 2021	499		498
Senior notes – 2.75% due 2022	497		496
Senior notes – 3.30% due 2023	348		348
Senior notes – 4.05% due 2023	248		248
Senior notes – 3.50% due 2024	596		596
Senior notes – 3.50% due 2025	496		496
Senior notes – 3.75% due 2026	596		596
Senior notes – 5.875% due 2033	297		297
Senior notes – 4.35% due 2047	492		492
Senior notes – 4.20% due 2048	592		—
Mortgage – 5.70% due 2035	367		370
Other	3		3
	6,078		5,487
Less current portion	263		262
	$	5,815	$	5,225

The senior notes in the table above are registered by the Company with the Securities and Exchange Commission and are not guaranteed.

The Company has established a short-term debt financing program of up to $1.5 billion through the issuance of commercial paper. The proceeds from the issuance of commercial paper are used for general corporate purposes. The Company had $249 million of commercial paper outstanding at March 31, 2018 at an effective interest rate of 2.44%.

In March 2018, the Company issued $600 million of 4.20% senior notes due 2048. The Company used the net proceeds for general corporate purposes.

In January 2017, the Company issued $500 million of 2.75% senior notes due 2022 and $500 million of 4.35% senior notes due 2047. The Company used the net proceeds for general corporate purposes, including the repayment of a $250 million debt maturity in April 2017.

The Company and certain of its foreign subsidiaries maintain a $1.5 billion multi-currency five-year unsecured revolving credit facility. The interest rate on this facility is based on LIBOR plus a fixed margin which varies with the Company's credit ratings. This facility expires in November 2020 and requires the Company to maintain certain coverage and leverage ratios which are tested quarterly. There were no borrowings outstanding under this facility at March 31, 2018.

Fair Value of Short-term and Long-term Debt

The estimated fair value of the Company’s short-term and long-term debt is provided below. Certain estimates and judgments were required to develop the fair value amounts. The fair value amounts shown below are not necessarily indicative of the amounts that the Company would realize upon disposition, nor do they indicate the Company’s intent or need to dispose of the financial instrument.



	March 31, 2018				December 31, 2017
(In millions)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Short-term debt	$	512	$	514	$	262	$	264
Long-term debt	$	5,815	$	5,908	$	5,225	$	5,444

The fair value of the Company’s short-term debt consists primarily of commercial paper and term debt maturing within the next year and its fair value approximates its carrying value. The estimated fair value of a primary portion of the Company's long-term debt is based on discounted future cash flows using current interest rates available for debt with similar terms and remaining maturities. Short- and long-term debt would be classified as Level 2 in the fair value hierarchy.