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Acquisition (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
Acquisition (Details) - USD ($) $ in Millions	Jul. 01, 2016	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Business Acquisition [Line Items]
Operating revenue		$ 3,599	$ 3,431	$ 7,070	$ 6,705
Goodwill		$ 4,675		4,675		$ 4,558
Engineered Fasteners and Components
Business Acquisition [Line Items]
Business acquisition, purchase price	$ 450
Operating revenue				$ 256
Goodwill	185
Intangible assets	$ 134
Finite-lived intangible assets, weighted average amortization period	16 years
Minimum \| Engineered Fasteners and Components
Business Acquisition [Line Items]
Finite-lived intangible assets, estimated useful life	4 years
Maximum \| Engineered Fasteners and Components
Business Acquisition [Line Items]
Finite-lived intangible assets, estimated useful life	17 years