Fair Value Measurement Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments under executive deferred compensation plan	[1]	$ 21,316	$ 22,168
Private equity securities	[2]	1,796	1,806
Foreign currency forward contracts, assets	[3]	36	631
Obligations under executive deferred compensation plan	[1]	21,316	22,168
Foreign currency forward contracts, liabilities	[3]	291
Quoted Prices in Active Markets for Identical Items (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments under executive deferred compensation plan	[1]	21,316	22,168
Private equity securities	[2]	24	21
Foreign currency forward contracts, assets	[3]	0	0
Obligations under executive deferred compensation plan	[1]	21,316	22,168
Foreign currency forward contracts, liabilities	[3]	0
Quoted Prices in Active Markets for Similar Items (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments under executive deferred compensation plan	[1]	0	0
Private equity securities	[2]	0	0
Foreign currency forward contracts, assets	[3]	36	631
Obligations under executive deferred compensation plan	[1]	0	0
Foreign currency forward contracts, liabilities	[3]	291
Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments under executive deferred compensation plan	[1]	0	0
Private equity securities	[2]	1,772	1,785
Foreign currency forward contracts, assets	[3]	0	0
Obligations under executive deferred compensation plan	[1]	0	$ 0
Foreign currency forward contracts, liabilities	[3]	0
Rockwood Merger Appraisal Shares Litigation
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability for appraisal shares	[4]	74,934
Rockwood Merger Appraisal Shares Litigation | Quoted Prices in Active Markets for Identical Items (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability for appraisal shares	[4]	0
Rockwood Merger Appraisal Shares Litigation | Quoted Prices in Active Markets for Similar Items (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability for appraisal shares	[4]	74,934
Rockwood Merger Appraisal Shares Litigation | Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability for appraisal shares	[4]	$ 0

[1] We maintain an Executive Deferred Compensation Plan (“EDCP”) that was adopted in 2001 and subsequently amended. The purpose of the EDCP is to provide current tax planning opportunities as well as supplemental funds upon the retirement or death of certain of our employees. The EDCP is intended to aid in attracting and retaining employees of exceptional ability by providing them with these benefits. We also maintain a Benefit Protection Trust (the “Trust”) that was created to provide a source of funds to assist in meeting the obligations of the EDCP, subject to the claims of our creditors in the event of our insolvency. Assets of the Trust are consolidated in accordance with authoritative guidance. The assets of the Trust consist primarily of mutual fund investments (which are accounted for as trading securities and are marked-to-market on a monthly basis through the consolidated statements of income) and cash and cash equivalents. As such, these assets and obligations are classified within Level 1.

[2] Primarily consists of private equity securities classified as available-for-sale and are reported in Investments in the condensed consolidated balance sheets. The changes in fair value are reported in Other income (expenses), net, in our consolidated statements of income. Holdings in private equity securities are typically valued using the net asset valuations provided by the underlying private investment companies and as such are classified within Level 3.

[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 2, “Acquisitions.”