Debt (Tables)

6 Months Ended

Jun. 30, 2017

Debt Disclosure [Abstract]

Approximate Fair Value and Related Carrying Value of Long-term Debt, Including Current Maturities

The approximate fair value and related carrying value of the Company's total long-term debt, including current maturities of long-term debt presented as short-term debt, as of June 30, 2017 and December 31, 2016 were as follows:

In millions	June 30, 2017		December 31, 2016
Fair value	$	7,898	$	8,281
Carrying value	7,360		7,827