Consolidated Statements of Cash Flows (Parenthetical) £ in Millions, $ in Millions		1 Months Ended		12 Months Ended
	Jun. 22, 2016 USD ($) promissory_note	Nov. 30, 2014 GBP (£)	Nov. 30, 2014 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 GBP (£)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Nov. 30, 2014 USD ($)
Supplemental Schedule of Noncash Investing and Financing Activities
Cash dividends declared, but not yet paid				$ 4.1		$ 4.2
Accrued capital expenditures				$ 0.4		0.8
Previous percentage ownership of noncontrolling owners				49.00%
Settlement of promissory notes	$ 17.7
Escrow account utilized for payment of assumed pension exit obligation		£ 8.8	$ 13.8		£ 0.8	1.1
Escrow account balance		£ 13.0						$ 21.7
Assets acquired, net of cash				$ 508.8		154.3	$ 611.0
Liabilities assumed				$ 64.5		$ 61.8	$ 314.8
Tobras | Disposal Group, Held-for-sale, Not Discontinued Operations
Supplemental Schedule of Noncash Investing and Financing Activities
Number of promissory notes settled in acquisition item | promissory_note	2