Income Taxes (Schedule of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Insurance and employee benefits	$ 3,004	$ 959
Inventory and contract balances	822	664
Warranty provisions	220	208
Other asset basis differences	637	614
Tax loss carryforwards	196	348
Tax credit carryforwards	959	930
Deferred Tax Assets, Valuation Allowance	(757)	(432)
Future Income Tax Benefits	5,081	3,291
Deferred Tax Liabilities Intangible Assets	7,786	4,205
Fixed assets	1,637	1,016
Other items, net	151	638
Future Income Taxes Payable	$ 9,574	$ 5,859