Inventories and Contracts in Progress (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Inventory [Line Items]
Inventory Costs in Excess of Average Cost Per Unit	$ 233	$ 13
Raw materials	2,040	2,037
Work-in-process	2,787	2,422
Finished goods	3,305	3,183
Contracts in progress	9,395	8,668
Inventories before payments and billings	17,527	16,310
Progress payments, secured by lien, on U.S. Government contracts	130	239
Billings on contracts in progress	8,693	7,936
Inventories and contracts in progress, net	8,704	8,135
Inventory Valuation Reserves	$ 877	$ 760
Percentage Of Inventory For Long Term Contracts Or Programs	68.00%	67.00%
Percentage Of Inventory For Long Term Contracts Scheduled For Delivery Within Succeeding 12 Months	41.00%	41.00%
UTC Aerospace Systems [Member]
Inventory [Line Items]
Capitalized Contract Development Costs	$ 140	$ 152

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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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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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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Amount of advances received from U.S. Government customers under long-term contracts which have been offset against inventory accounts at the balance sheet date.

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