Inventory (Narrative) (Details) - USD ($) $ in Millions	Apr. 02, 2017	Dec. 31, 2016
Inventory [Line Items]
Capitalized precontract costs, work in process inventories	$ 185	$ 189

Amount, before valuation and last-in first out (LIFO) reserves, of costs capitalized in inventory classified as other, expected to be sold, or consumed within one year or operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_OtherInventoryCapitalizedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant