SEGMENT INFORMATION - THIRD PARTY NET SALES, EXCLUDING PRECIOUS METAL CONTENT (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue, Major Customer [Line Items]
Net Sales, including precious metal content	$ 992.7	$ 1,022.0	$ 1,893.2	$ 1,794.6
Dental And Healthcare Consumables
Revenue, Major Customer [Line Items]
Net Sales, including precious metal content	554.1	543.8	1,065.3	1,032.7
Technologies
Revenue, Major Customer [Line Items]
Net Sales, including precious metal content	438.6	478.2	827.9	761.9
Operating Segments
Revenue, Major Customer [Line Items]
Net Sales, including precious metal content	983.0	1,004.7	1,872.4	1,759.2
Operating Segments | Dental And Healthcare Consumables
Revenue, Major Customer [Line Items]
Net Sales, including precious metal content	544.4	526.7	1,044.6	997.5
Operating Segments | Technologies
Revenue, Major Customer [Line Items]
Net Sales, including precious metal content	438.6	478.0	827.8	761.7
Segment Reconciling Items
Revenue, Major Customer [Line Items]
Net Sales, including precious metal content	$ 9.7	$ 17.3	$ 20.8	$ 35.4