LONG-TERM DEBT (Tables)

12 Months Ended

Dec. 31, 2015

LONG-TERM DEBT

Long-term debt

Balance at December 31, (in millions)	2015			2014
2.50% senior notes due 2016	$	700		$	700
4.125% senior notes due 2016	750			750
1.75% senior notes due 2017	1,250			1,250
1.50% senior notes due 2018	500			500
9.25% senior debentures due 2019	116			116
4.10% senior notes due 2021	1,249			1,249
3.125% senior notes due 2022	813			813
2.70% senior notes due 2023	1,191			1,191
8.75% medium-term notes due 2023	22			22
3.50% senior notes due 2025	750			—
7.2% senior debentures due 2028	82			82
8.45% senior debentures due 2029	116			116
4.625% senior notes due 2045	750			—
Variable rate bonds due 2030 (0.15% and 0.04% as of December 31, 2015 and 2014, respectively )	68			68
	8,357			6,857
Less:
Unamortized discount, net	(24		)	(19		)
Current maturities	(1,450		)	—
Total	$	6,883		$	6,838