Post-Retirement Benefits - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Sep. 30, 2014
Defined Benefit Plan Disclosure [Line Items]
Contributions to the Compensation Plan by the employer	$ 0.6
Contributions to the Compensation Plan by the employer in remainder of fiscal year 2015	1.8
Unfunded Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Pension liability	$ 7.1