Unapproved Change Orders, and Claims, Against Clients and Estimated Recoveries of Claims Against Suppliers and Subcontractors (Rollforward) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Unapproved Change Orders [Roll Forward]
Amounts included in project estimates-at-completion at January 1,	$ 973	$ 924
Increase (decrease), including foreign currency effect	16	(17)
Amounts included in project estimates-at-completion at March 31,	989	907
Amounts recognized over time based on progress at March 31,	$ 965	$ 843

The amount of costs incurred on unapproved change orders when it is probable that the cost will be recovered through a change in the contract price.

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(3)(c)(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 910
-SubTopic 310
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68065756&loc=d3e49324-109356

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 910
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68053980&loc=d3e50000-109363

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