Revenue from Contracts With Customers (Tables)

3 Months Ended

Mar. 31, 2018

Revenue from Contract with Customer [Abstract]

Schedule of the disaggregation of revenue by timing of transfer of control

	Three Months Ended March 31, 2018
($ in millions)	Point in Time		Over Time		Total
Total net sales	$	662	$	2,123	$	2,785

Schedule of balances of contract liabilities

	Contracts		Contract
	Liabilities		Liabilities
($ in millions)	(Current)		(Noncurrent)
Balance at December 31, 2017	$	45	$	—
Increase		7		6
Balance at March 31, 2018	$	52	$	6

Schedule of transaction price allocated to remaining performance obligations

($ in millions)	Rolling Twelve Months		Thereafter		Total
Sales expected to be recognized on multi-year contracts in place as of March 31, 2018	$	862	$	777	$	1,639