Commitments, Contingencies and Other Matters (Narrative) (Detail) $ in Thousands	1 Months Ended	6 Months Ended	12 Months Ended
	Apr. 30, 2014 USD ($)	Dec. 31, 2015 USD ($) Entity	Jun. 30, 2009 USD ($)	Jun. 30, 2015 USD ($)
Pulvair Site Group
Commitments and Contingencies Disclosure [Line Items]
Loss contingency, damages sought		$ 1,700
Arsynco, Inc
Commitments and Contingencies Disclosure [Line Items]
Site contingency loss exposure not accrued, low estimate		16,500
Site contingency loss exposure not accrued, high estimate		18,300
Accrual for environmental loss contingencies		10,571		$ 11,079
BASF Corporation
Commitments and Contingencies Disclosure [Line Items]
Partial reimbursement of environmental remediation costs previously expensed			$ 550
Environmental remediation costs expensed in prior years			$ 1,200
Future remediation costs receivable		4,756		4,985
Subsidiary
Commitments and Contingencies Disclosure [Line Items]
Amount expected to be paid for product registrations and various task force groups		2,360
Amount accrued for product registrations and various task force groups		$ 0		0
Berry's Creek Study Area | Arsynco, Inc
Commitments and Contingencies Disclosure [Line Items]
Number of potentially responsible parties | Entity		150
Pack Pharmaceuticals Llc | Rising
Commitments and Contingencies Disclosure [Line Items]
Percentage of issued and outstanding membership interests acquired	100.00%
Purchase price, earn-out period	3 years
Purchase price, maximum earn-out amount	$ 15,000
Accrued contingent consideration		$ 833		$ 783