Divestitures Divestitures - Additional Information (Details) - USD ($) $ in Thousands				3 Months Ended
		Feb. 01, 2016	Jan. 04, 2016	Mar. 31, 2016		Mar. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds from divestitures, net				$ 307,165		$ 0
Gain (loss) on sales of business				121,324	[1]	$ 0
Metal Sulfides Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds from divestitures, net			$ 137,000
Gain (loss) on sales of business				11,500
Mineral Flame Retardants and Specialty Chemicals Businesses
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds from divestitures, net		$ 187,000
Gain (loss) on sales of business				111,300
Magnifin Magnesiaprodukte GmbH & Co. KG
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership Percentage		50.00%
Corporate
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on sales of business	[1]			(1,533)
Corporate | Wafer Reclaim
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on sales of business				$ (1,500)

[1] See Note 3, “Divestitures.”