Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2019

Fair Value Disclosures [Abstract]

Assets measured at fair value on a recurring basis

	March 31, 2019								December 31, 2018
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Assets	(in millions)
Investments (Note 4)	$	7,598	$	321	$	3	$	7,922	$	7,493	$	317	$	372	$	8,182
Derivative contracts, at fair value (Note 6)(1)	—		27		—		27		7		517		—		524
	$	7,598	$	348	$	3	$	7,949	$	7,500	$	834	$	372	$	8,706
Liabilities
Securities sold, not yet purchased (Note 4)	$	447	$	—	$	—	$	447	$	468	$	—	$	—	$	468
Other liabilities	—		16		—		16		—		2		—		2
Derivative contracts, at fair value (Note 6)	—		722		—		722		—		36		—		36
	$	447	$	738	$	—	$	1,185	$	468	$	38	$	—	$	506

⁽¹⁾  Amounts are classified within other assets in our condensed consolidated balance sheets.

Assets measured at fair value on a recurring basis for which we use Level 3 inputs to determine fair value

	Three Months Ended March 31,
	2019			2018
	(in millions)
Balance at January 1	$	372		$	278
Net gains recognized in income	89			23
Sales	(458		)	—
Balance at March 31	$	3		$	301