Revenue from Contracts With Customers (Tables)

6 Months Ended

Jun. 30, 2018

Revenue from Contract with Customer [Abstract]

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

	Three Months Ended June 30, 2018						Six Months Ended June 30, 2018
($ in millions)	Point in Time		Over Time		Total		Point in Time		Over Time		Total
Total net sales	$	755	$	2,346	$	3,101	$	1,417	$	4,469	$	5,886

Schedule of balances of contract liabilities

	Contracts		Contract
	Liabilities		Liabilities
($ in millions)	(Current)		(Noncurrent)
Balance at December 31, 2017	$	45	$	—
Increase		20		6
Balance at June 30, 2018	$	65	$	6

Schedule of transaction price allocated to remaining performance obligations

($ in millions)	Next Twelve Months		Thereafter		Total
Sales expected to be recognized on multi-year contracts in place as of June 30, 2018	$	915	$	912	$	1,827