Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2018

Commitments and Contingencies Disclosure [Abstract]

Schedule of Future Minimum Rental Payments for Operating Leases

At December 31, 2018, future minimum rental payments under non-cancelable operating leases were:

Year	($ in millions)
2019	$	13.0
2020	10.5
2021	7.8
2022	6.9
2023	5.5
Thereafter	37.8
Total	$	81.5