Debt and Credit Facility (Tables)

3 Months Ended

Mar. 31, 2015

Debt Disclosure [Abstract]

Schedule of Debt Instruments

The following table summarizes the carrying amounts of our borrowings under various financing arrangements (in millions):

Type of Borrowing	Description	Issue Date	Due Date	Interest Rate	March 31, 2015		December 31, 2014
Convertible Senior	May 2016 Notes	July 2010	May 2016	1.625%	$	442	$	483
Senior Unsecured	April 2021 Notes	March 2011	April 2021	4.50%	995		995
Senior Unsecured	December 2016 Notes	December 2011	December 2016	3.05%	700		700
Senior Unsecured	December 2021 Notes	December 2011	December 2021	4.40%	1,248		1,248
Senior Unsecured	December 2041 Notes	December 2011	December 2041	5.65%	998		998
Senior Unsecured	April 2019 Notes	March 2014	April 2019	2.05%	499		499
Senior Unsecured	April 2024 Notes	March 2014	April 2024	3.70%	1,747		1,747
Senior Unsecured	April 2044 Notes	March 2014	April 2044	4.80%	1,747		1,747
Senior Unsecured	February 2020 Notes	November 2014	February 2020	2.35%	499		499
Senior Unsecured	February 2025 Notes	November 2014	February 2025	3.50%	1,748		1,748
Senior Unsecured	February 2045 Notes	November 2014	February 2045	4.50%	1,740		1,740
Total debt, net					12,363		12,404
Less current portion					442		483
Total long-term debt, net					$	11,921	$	11,921