Debt And Lines Of Credit (Tables)

12 Months Ended

Dec. 31, 2017

Debt Instruments [Abstract]

Debt Extinguishment [Table Text Block]

Amounts related to early debt extinguishment during the years ended December 31, 2017, 2016 and 2015 were as follows:

In millions	2017		2016		2015
Debt reductions (a)	$	993	$	266	$	2,151
Pre-tax early debt extinguishment costs (b)	83		29		207

(a) Reductions related to notes with interest rates ranging from 1.57% to 9.38% with original maturities from 2015 to 2030 for the years ended December 31, 2017, 2016 and 2015. Includes the $630 million payment for a portion of the Special Purpose Entity Liability for the year ended December 31, 2015 (see Note 12 Variable Interest Entities).

(b) Amounts are included in Restructuring and other charges in the accompanying consolidated statements of operations.

Summary Of Long-Term Debt [Table Text Block]

A summary of long-term debt follows:

In millions at December 31	2017			2016
9 3/8% note – due 2019	$	—		$	295
8.7% note – due 2038	264			264
7.95% debenture – due 2018	—			382
7.5% note – due 2021	409			598
7.3% note – due 2039	721			721
6 7/8% notes – due 2023 – 2029	131			131
6.65% note – due 2037	4			4
6 5/8% note – due 2018	—			72
6.4% to 7.75% debentures due 2025 – 2027	143			142
6.0% note – due 2041	585			585
5.00% to 5.15% notes – due 2035 – 2046	1,281			1,280
4.8% note – due 2044	796			796
4.75% note – due 2022	817			810
3.00% to 4.40% notes – due 2024 – 2048	4,775			3,786
Floating rate notes – due 2017 – 2025 (a)	650			763
Environmental and industrial development bonds – due 2017 – 2035 (b)	585			681
Other (c)	(4		)	4
Total (d)	11,157			11,314
Less: current maturities	311			239
Long-term debt	$	10,846		$	11,075

(a) The weighted average interest rate on these notes was 2.6% in 2017 and 2.2% in 2016.

(b) The weighted average interest rate on these bonds was 6.0% in 2017 and 5.9% in 2016.

(c) Includes $70 million and $69 million of debt issuance costs as of December 31, 2017 and 2016, respectively.

(d) The fair market value was approximately $12.3 billion at December 31, 2017 and $12.0 billion at December 31, 2016.