Other Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2017

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Carrying Values and Fair Values of Other Financial Instruments

The carrying values and fair values of Arconic’s financial instruments were as follows:

	2017				2016
December 31,	Carrying value		Fair value		Carrying value		Fair value
Cash and cash equivalents	$	2,150	$	2,150	$	1,863	$	1,863
Restricted cash	4		4		15		15
Derivatives – current asset	61		61		14		14
Noncurrent receivables	20		20		21		21
Derivatives – noncurrent asset	33		33		10		10
Available-for-sale securities	106		106		102		102
Investment in common stock of Alcoa Corporation	—		—		1,020		1,020
Short-term debt	38		38		40		40
Derivatives – current liability	45		45		5		5
Commercial paper	—		—		—		—
Derivatives – noncurrent liability	14		14		3		3
Contingent payment related to an acquisition	—		—		78		78
Long-term debt, less amount due within one year	6,806		7,443		8,044		8,519