Pension Plans and Other Postretirement Benefits Reconciliation of Benefit Obligations, Plan Assets and Funded Status of Plans, as well as Summary of Significant Assumptions for Benefit Plans (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
U.S. Pension Plans
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance		$ 729,652		$ 629,337
Service cost		1,233		7,029		$ 12,177
Interest cost		31,231		30,491		28,406
Plan amendments		0		0
Actuarial (gain) loss		(55,851)		130,887
Benefits paid		(38,300)		(37,866)
Acquisitions		39,125		0
Divestitures	[1]	0		(30,226)
Reclass to liabilities held for sale		0		0
Employee contributions		0		0
Foreign exchange gain		0		0
Settlements/curtailments		0		0
Other		0		0
Benefit obligation, ending balance		707,090		729,652		629,337
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance		598,250		605,604
Actual return on plan assets		(16,789)		53,696
Employer contributions		1,606		7,042
Benefits paid		(38,300)		(37,866)
Acquisitions		29,314		0
Divestitures	[1]	0		(30,226)
Employee contributions		0		0
Foreign exchange loss		0		0
Settlements/curtailments		0		0
Other		0		0
Fair value of plan assets, Ending Balance		574,081		598,250		605,604
Funded status		(133,009)		(131,402)
Current liabilities (accrued expenses)		(1,110)		(3,219)
Noncurrent liabilities (pension benefits)		(131,899)		(128,183)
Net pension liability		(133,009)		(131,402)
Prior service benefit		(211)		(286)
Net amount recognized		$ (211)		$ (286)
Weighted-average assumptions used to determine benefit obligations at December 31:
Discount Rate		4.67%		4.19%
Rate of compensation increase		0.00%		0.00%
Foreign Pension Plans
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance		$ 53,112		$ 49,245
Service cost		6,034		1,746		1,785
Interest cost		9,875		1,571		1,477
Plan amendments		870		0
Actuarial (gain) loss		(42,977)		10,341
Benefits paid		(16,118)		(3,913)
Acquisitions		416,150		0
Divestitures	[1]	0		0
Reclass to liabilities held for sale		(26,608)		0
Employee contributions		478		283
Foreign exchange gain		(26,708)		(6,161)
Settlements/curtailments		(582)		0
Other		331		0
Benefit obligation, ending balance		373,857		53,112		49,245
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance		9,444		10,941
Actual return on plan assets		140		499
Employer contributions		16,392		2,940
Benefits paid		(16,118)		(3,913)
Acquisitions		109,875		0
Divestitures	[1]	0		0
Employee contributions		478		283
Foreign exchange loss		(3,237)		(1,306)
Settlements/curtailments		(582)		0
Other		314		0
Fair value of plan assets, Ending Balance		116,706		9,444		10,941
Funded status		(257,151)		(43,668)
Current liabilities (accrued expenses)		(7,498)		(1,316)
Noncurrent liabilities (pension benefits)		(249,653)		(42,352)
Net pension liability		(257,151)		(43,668)
Prior service benefit		(1,052)		(321)
Net amount recognized		$ (1,052)		$ (321)
Weighted-average assumptions used to determine benefit obligations at December 31:
Discount Rate		2.89%		1.85%
Rate of compensation increase		3.17%		3.40%
Other Postretirement Benefits
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance		$ 64,500		$ 62,832
Service cost		137		216		309
Interest cost		2,573		3,040		2,764
Actuarial (gain) loss		(5,682)		3,741
Benefits paid		(5,042)		(5,329)
Acquisitions		2,607		0
Settlements/curtailments	[2]	(2,594)		0
Benefit obligation, ending balance		56,499		64,500		62,832
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance		4,439	[3]	5,620
Actual return on plan assets		280		214
Employer contributions		3,615		3,934
Benefits paid		(5,042)		(5,329)
Fair value of plan assets, Ending Balance		3,292	[4]	4,439	[3]	$ 5,620
Funded status		(53,207)		(60,061)
Current liabilities (accrued expenses)		(3,560)		(3,637)
Noncurrent liabilities (pension benefits)		(49,647)		(56,424)
Net pension liability		(53,207)		(60,061)
Prior service benefit		239		334
Net amount recognized		$ 239		$ 334
Weighted-average assumptions used to determine benefit obligations at December 31:
Discount Rate		4.59%		4.15%
Rate of compensation increase		3.50%		3.50%

[1] Reduction in benefit obligations and plan assets in 2014 is in connection with the sale of our antioxidant, ibuprofen and propofol businesses and assets which closed on September 1, 2014. See Note 3 “Divestitures” for additional information about this transaction.

[2] We assumed responsibility for one domestic OPEB plan in connection with the acquisition of Rockwood which covered a small number of active employees and retirees. This plan was terminated in the first quarter of 2015 and provisions were made for the affected employees and retirees to receive benefits under an existing plan.

[3] As a result of our global operating and financing activities, we are exposed to market risks from changes in foreign currency exchange rates, which may adversely affect our operating results and financial position. When deemed appropriate, we minimize our risks from foreign currency exchange rate fluctuations through the use of foreign currency forward contracts. Unless otherwise noted, these derivative financial instruments are not designated as hedging instruments under ASC 815, Derivatives and Hedging. The foreign currency forward contracts are valued using broker quotations or market transactions in either the listed or over-the-counter markets. As such, these derivative instruments are classified within Level 2.

[4] See Note 15 “Pension Plans and Other Postretirement Benefits” for further information about fair value measurements of our pension and postretirement plan assets, including the reconciliations of the plans’ Level 3 assets.