Inventories and Contracts in Progress (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Raw materials	$ 2,218	$ 2,037
Work-in-process	2,639	2,422
Finished goods	3,058	3,183
Contracts in progress	8,900	8,668
Inventory before payments and billings	16,815	16,310
Progress payments, secured by lien, on U.S. Government contracts	148	239
Billings on contracts in progress	8,160	7,936
Inventories and contracts in progress, net	8,507	8,135
UTC Aerospace Systems [Member]
Inventory [Line Items]
Other Inventory, Capitalized Costs, Gross	$ 151	$ 152

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