Commitments and Contingencies - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015
Loss Contingencies [Line Items]
Environmental remediation liabilities - discounted	$ 21,400,000
Environmental remediation liabilities - undiscounted	34,500,000
Potential revision on future environmental remediation costs before tax	22,000,000
Minimum
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies, Discount Rate	2.80%
Maximum
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies, Discount Rate	4.30%
Rockwood Holdings, Inc.
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies from Rockwood Acquisition	$ 31,391,000