Marketable Securities (Tables)

6 Months Ended

Jun. 30, 2019

Schedule of marketable securities

(Millions)	June 30, 2019		December 31, 2018
Commercial paper	$	102	$	366
Certificates of deposit/time deposits		34		10
U.S. municipal securities		3		3
Asset-backed securities		—		1
Current marketable securities	$	139	$	380
U.S. municipal securities	$	46	$	37
Non-current marketable securities	$	46	$	37
Total marketable securities	$	185	$	417

Marketable securities by contractual maturity

(Millions)	June 30, 2019
Due in one year or less	$	139
Due after one year through five years		13
Due after five years through ten years		24
Due after ten years		9
Total marketable securities	$	185