Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2017

Fair Value Disclosures [Abstract]

Financial instruments measured at fair value on a recurring basis

Financial instruments measured at fair value on a recurring basis as of September 30, 2017 and December 31, 2016 are as follows (in millions):

	As of September 30, 2017						As of December 31, 2016
	Level 1		Level 2 and 3		Total		Level 1		Level 2 and 3		Total
Assets at fair value:
Long-term investment in equity securities	$	—	$	—	$	—	$	432	$	—	$	432
U.S. Treasury securities	734		—		734		500		—		500
Mutual Funds	16		—		16		23		—		23
Total assets at fair value	$	750	$	—	$	750	$	955	$	—	$	955