Leases Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Leases [Abstract]
Lease term extension	15 years
Termination period	one year
Operating lease expense under ASC 842	$ 162
Operating lease expense under ASC 840		$ 109	$ 84