Commitments, Contingencies and Other Matters (Narrative) (Detail) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2017 USD ($) Entity	Mar. 31, 2017 USD ($) Entity	Jun. 30, 2009 USD ($)	Jun. 30, 2016 USD ($)
Commitments and Contingencies Disclosure [Line Items]
Environmental remediation charge		$ 903
Pulvair Site Group
Commitments and Contingencies Disclosure [Line Items]
Loss contingency, damages sought		1,700
Arsynco, Inc
Commitments and Contingencies Disclosure [Line Items]
Accrual for environmental loss contingencies	$ 9,120	9,120		$ 12,532
Arsynco, Inc | Minimum
Commitments and Contingencies Disclosure [Line Items]
Site contingency loss exposure not accrued		21,500
Arsynco, Inc | Maximum
Commitments and Contingencies Disclosure [Line Items]
Site contingency loss exposure not accrued		23,300
Arsynco, Inc | Selling, General and Administrative Expenses
Commitments and Contingencies Disclosure [Line Items]
Environmental remediation charge	733	903
BASF Corporation
Commitments and Contingencies Disclosure [Line Items]
Partial reimbursement of environmental remediation costs previously expensed			$ 550
Gain related to partial reimbursement			550
Environmental remediation costs expensed in prior years			$ 1,200
Future remediation costs receivable	4,104	4,104		$ 5,639
Subsidiary
Commitments and Contingencies Disclosure [Line Items]
Amount expected to be paid for product registrations and various task force groups	$ 1,317	$ 1,317
Berry's Creek Study Area | Arsynco, Inc
Commitments and Contingencies Disclosure [Line Items]
Number of potentially responsible parties | Entity	150	150