Inventories and Contracts in Progress (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Raw materials	$ 2,209	$ 2,037
Work-in-process	2,807	2,422
Finished goods	3,438	3,183
Contracts in progress	9,580	8,668
Inventory before payments and billings	18,034	16,310
Progress payments, secured by lien, on U.S. Government contracts	157	239
Billings on contracts in progress	8,796	7,936
Inventories and contracts in progress, net	9,081	8,135
Inventory [Line Items]
Inventory Costs in Excess of Average Cost Per Unit	144	13
UTC Aerospace Systems [Member]
Inventory [Line Items]
Other Inventory, Capitalized Costs, Gross	$ 148	$ 152

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount before valuation and LIFO reserves, and progress payments, of inventory associated with long-term contracts, expected to be sold, or consumed within one year or operating cycle, if longer.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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