Debt (Tables)

12 Months Ended

Dec. 31, 2015

Debt Instrument [Line Items]

Key Components of Convertible Debt

The following table represents the key components of interest expense on the convertible debt (table in millions):

	For the year ended
	December 31, 2013
Contractual interest expense on the coupon	$	27
Amortization of the discount component recognized as interest expense	58
Total interest expense on the convertible debt	$	85

Our long-term debt as of December 31, 2015 and December 31, 2014 was as follows (dollars in millions):

			Carrying Value
Senior Notes	Issued at Discount to Par		December 31, 2015			December 31, 2014
$2.5 billion 1.875% Notes due 2018	99.943	%	$	2,499		$	2,499
$2.0 billion 2.650% Notes due 2020	99.760	%	1,996			1,996
$1.0 billion 3.375% Notes due 2023	99.925	%	1,000			1,000
			$	5,495		$	5,495
Debt issuance costs			(20		)	(26		)
Net long-term debt			$	5,475		$	5,469