Revenue from Contracts With Customers (Tables)

9 Months Ended

Sep. 30, 2018

Revenue from Contract with Customer [Abstract]

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

	Three Months Ended September 30, 2018						Nine Months Ended September 30, 2018
($ in millions)	Point in Time		Over Time		Total		Point in Time		Over Time		Total
Total net sales	$	665	$	2,281	$	2,946	$	2,082	$	6,750	$	8,832

Schedule of balances of contract liabilities

	Contracts		Contract
	Liabilities		Liabilities
($ in millions)	(Current)		(Noncurrent)
Balance at December 31, 2017	$	45	$	—
Increase		22		8
Balance at September 30, 2018	$	67	$	8

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 September 30, 2018	$	849	$	866	$	1,715