Company Restructuring (Tables)

6 Months Ended

Jun. 30, 2018

Restructuring and Related Activities [Abstract]

Schedule of changes in the restructuring liability

Restructuring activity during the period
($ in millions)	Employee costs			Exit costs			Total liability
Restructuring liability as of December 31, 2017	$	15		$	30		$	45
Expense incurred	31			18			49
Adjustments to liability	1			(1		)	—
Payments and non-cash pension settlements	(6		)	(21		)	(27		)
Restructuring liability as of June 30, 2018	$	41		$	26		$	67