Held for Sale and Discontinued Operations - Net Change Cash From Discontinued Operations (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Net Cash Provided by (Used in) Discontinued Operations [Abstract]
Cash balances at beginning of period	$ 97.1	$ 80.2
Cash balances at end of period	131.1	53.3
Net income tax payment to national governments	0.0	0.0
Discontinued Operations
Net Cash Provided by (Used in) Discontinued Operations [Abstract]
Net cash provided from operations - discontinued operations	0.1	87.3
Net cash used for investing activities - discontinued operations	(0.1)	(43.6)
Net cash used for financing activities - discontinued operations	0.0	(42.0)
Net change in cash during the period	0.0	1.7
Cash balances at beginning of period	0.0	70.5
Cash balances at end of period	0.0	71.3
Interest paid	0.0	(6.3)
Net income tax payment to national governments	0.0	0.0
Discontinued Operations, Held-for-sale
Net Cash Provided by (Used in) Discontinued Operations [Abstract]
Cash balances at beginning of period	0.0	70.5
Cash balances at end of period	0.0	71.3
Disposal Group, Held-for-sale, Not Discontinued Operations
Net Cash Provided by (Used in) Discontinued Operations [Abstract]
Net change in cash held for sale, excluding discontinued operations	$ 0.0	$ (0.9)