Lease Commitments Lease Commitments - Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating Lease, Expense	$ 444	$ 463	$ 467
Variable Lease, Cost	49	57	53
Sublease Income	(16)	(14)	(16)
Finance Lease, Right-of-Use Asset, Amortization	34	27	15
Finance Lease, Interest Expense	14	15	6
Lease, Cost	$ 525	$ 548	$ 525