Acquisitions (Details) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended				12 Months Ended
	Feb. 01, 2017	Dec. 31, 2016	Jan. 12, 2015	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Gain on acquisition								$ 6,221	$ 0	$ 0
Other acquisitions								44,367	126,747	48,845
Inventories		$ 450,263		$ 450,263				592,781	450,263
Acquisition and integration related costs				13,047	$ 6,749	$ 19,030	$ 18,558	0	57,384	132,299
Goodwill		1,540,032		1,540,032				1,610,355	1,540,032	1,460,552
Purchase of noncontrolling interest								0	0	4,784
Sales de Magnesio Ltda.
Business Acquisition [Line Items]
Percentage of equity interests acquired	50.00%
Total purchase price	$ 8,300
Jiangxi Jiangli New Materials Science and Technology Co. Ltd.
Business Acquisition [Line Items]
Other acquisitions		$ 145,000
Accounts receivable								600
Property, plant and equipment								24,100
Other intangibles								46,300
Accounts payable								2,800
Deferred tax liabilities								6,300
Fair value of net working capital								6,200
Inventories								37,100
Inventory markup								23,100
Acquired finite-lived intangible assets, weighted average useful life		17 years
Rockwood Holdings, Inc.
Business Acquisition [Line Items]
Total purchase price			$ 5,700,000
Inventory markup			103,400
Acquisition and integration related costs									52,100	123,900
Goodwill			$ 2,800,000
Utilization of inventory markup									103,400
Pro forma Net sales									3,684,665
Pro forma Net income									$ 527,997
Pro forma Net income from continuing operations per share: Basic (in dollars per share)									$ 4.75
Pro forma Net income from continuing operations per share: Diluted (in dollars per share)									$ 4.73
Other significant projects
Business Acquisition [Line Items]
Acquisition and integration related costs									$ 5,300	8,400
Shanghai Chemetall
Business Acquisition [Line Items]
Acquisition of remaining interest in Shanghai Chemetall									57,600
Chemal GmbH
Business Acquisition [Line Items]
Other acquisitions									2,200
Nanjing Chemetall Surface Treatment Technologies
Business Acquisition [Line Items]
Purchase of noncontrolling interest									4,800
Acquisition and integration related costs | Rockwood Holdings, Inc.
Business Acquisition [Line Items]
Acquisition and integration related costs									137,700
Patents and technology | Jiangxi Jiangli New Materials Science and Technology Co. Ltd.
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life		20 years
Customer lists and relationships | Jiangxi Jiangli New Materials Science and Technology Co. Ltd.
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life		13 years
Other | Jiangxi Jiangli New Materials Science and Technology Co. Ltd.
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life		20 years
Other (expenses) income, net | Sales de Magnesio Ltda.
Business Acquisition [Line Items]
Gain on acquisition								6,200
Cost of sales
Business Acquisition [Line Items]
Acquisition and integration related costs								14,300
Cost of sales | Jiangxi Jiangli New Materials Science and Technology Co. Ltd.
Business Acquisition [Line Items]
Utilization of inventory markup								23,100
Cost of sales | Rockwood Holdings, Inc.
Business Acquisition [Line Items]
Utilization of inventory markup										55,900
Selling, general and administrative expenses
Business Acquisition [Line Items]
Acquisition and integration related costs								19,600
Reportable Segments | Lithium and Advanced Materials
Business Acquisition [Line Items]
Goodwill		$ 1,348,261		$ 1,348,261				1,396,140	$ 1,348,261	$ 1,267,505
Reportable Segments | Lithium and Advanced Materials | Jiangxi Jiangli New Materials Science and Technology Co. Ltd.
Business Acquisition [Line Items]
Goodwill								$ 83,100