Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2014

Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]

Schedule of Components of Net Periodic Benefit Cost

The components of net periodic benefit cost for the three months ended June 30 were as follows ($ in millions):

	Pension benefits						Other retirement benefits					Total
	2014			2013			2014			2013		2014			2013
Service cost	$	2.5		$	2.5		$	0.1		$	0.3	$	2.6		$	2.8
Interest cost	4.3			3.7			0.1			0.3		4.4			4.0
Expected return on assets	(4.8		)	(4.3		)	—			—		(4.8		)	(4.3		)
Amortization of prior service credit	(0.3		)	(0.3		)	—			—		(0.3		)	(0.3		)
Recognized actuarial losses (gains)	1.1			2.3			(0.3		)	—		0.8			2.3
Net periodic benefit cost	$	2.8		$	3.9		$	(0.1	)	$	0.6	$	2.7		$	4.5

	Pension benefits				Other retirement benefits					Total
	2014		2013		2014			2013		2014		2013
U.S. plans	$	2.0	$	3.1	$	(0.1	)	$	0.6	$	1.9	$	3.7
International plans	0.8		0.8		—			—		0.8		0.8
Net periodic benefit cost	$	2.8	$	3.9	$	(0.1	)	$	0.6	$	2.7	$	4.5

The components of net periodic benefit cost for the six months ended June 30 were as follows ($ in millions):

	Pension benefits						Other retirement benefits					Total
	2014			2013			2014			2013		2014			2013
Service cost	$	5.1		$	5.0		$	0.2		$	0.7	$	5.3		$	5.7
Interest cost	8.5			7.4			0.2			0.5		8.7			7.9
Expected return on assets	(9.7		)	(8.6		)	—			—		(9.7		)	(8.6		)
Amortization of transition obligation	—			0.1			—			—		—			0.1
Amortization of prior service credit	(0.6		)	(0.7		)	—			—		(0.6		)	(0.7		)
Recognized actuarial losses (gains)	2.3			4.7			(0.7		)	—		1.6			4.7
Net periodic benefit cost	$	5.6		$	7.9		$	(0.3	)	$	1.2	$	5.3		$	9.1

	Pension benefits				Other retirement benefits					Total
	2014		2013		2014			2013		2014		2013
U.S. plans	$	4.1	$	6.3	$	(0.3	)	$	1.2	$	3.8	$	7.5
International plans	1.5		1.6		—			—		1.5		1.6
Net periodic benefit cost	$	5.6	$	7.9	$	(0.3	)	$	1.2	$	5.3	$	9.1