Pensions and Other Postretirement Benefits (Tables)

6 Months Ended

Jun. 30, 2018

Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]

Net Periodic Benefit Cost

The net periodic pension and other postretirement benefit costs for the three and six months ended June 30, 2018 and 2017 were as follows:

	Pension
	Three Months Ended June 30						Six Months Ended June 30
($ in millions)	2018			2017			2018			2017
Service cost		$8			$8			$16			$17
Interest cost	24			25			48			49
Expected return on plan assets	(38		)	(36		)	(76		)	(70		)
Amortization of actuarial losses	16			19			32			38
Pension settlement charge	—			—			—			22
Net periodic benefit cost		$10			$16			$20			$56

	Other Postretirement Benefits
	Three Months Ended June 30						Six Months Ended June 30
($ in millions)	2018			2017			2018			2017
Service cost		$3			$3			$5			$5
Interest cost	6			5			12			12
Amortization of actuarial losses	4			1			9			6
Amortization of prior service credit	(15		)	(17		)	(30		)	(30		)
Net periodic benefit cost		($2	)		($8	)		($4	)		($7	)

Defined Contribution Plan Disclosures

	Three Months Ended June 30				Six Months Ended June 30
($ in millions)	2018		2017		2018		2017
U.S. defined benefit pension contributions		$—		$—		$25		$29
Non-U.S. defined benefit pension mandatory contributions		$5		$3		$10		$8