Commitments, Contingencies and Other Matters (Detail) In Thousands, unless otherwise specified				3 Months Ended	12 Months Ended			3 Months Ended		0 Months Ended
	Mar. 31, 2012 Entity	Sep. 30, 2012 Subsidiary [Member] USD ($)	Jun. 30, 2012 Subsidiary [Member] USD ($)	Sep. 30, 2012 Pulvair Site Group [Member] USD ($)	Jun. 30, 2009 BASF Corporation [Member] USD ($)	Sep. 30, 2012 BASF Corporation [Member] USD ($)	Jun. 30, 2012 BASF Corporation [Member] USD ($)	Sep. 30, 2012 Arsynco Inc. [Member] USD ($)	Jun. 30, 2012 Arsynco Inc. [Member] USD ($)	Oct. 29, 2012 United Phosphorous Limited [Member] Damages from Product Defects [Member] USD ($)	Oct. 29, 2012 United Phosphorous Limited [Member] Damages from Product Defects [Member] GBP (£)
Commitments and Contingencies Disclosure [Line Items]
Loss contingency, damages sought				$ 1,700						$ 7,200	£ 4,500
Site contingency loss exposure not accrued, low estimate								8,400
Site contingency loss exposure not accrued, high estimate								10,200
Accrual for environmental loss contingencies								7,192	7,566
Partial reimbursement of environmental remediation costs previously expensed					550
Environmental remediation costs expensed in prior years					1,200
Future remediation costs receivable						3,237	3,405
Number of potentially responsible parties	150
Amount expected to be paid for product registrations and various task force groups		2,047
Amount accrued for product registrations and various task force groups		$ 121	$ 242