Insurance settlement - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended		0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Jan. 31, 2015
Insurance [Line Items]
Insurance settlement	$ 1,000	$ 0	$ 1,000	$ 0
Subsequent Event [Member]
Insurance [Line Items]
Insurance settlement					$ 1,000
Insurance claim, malpractice description					Claim made under its insurance policy covering, among other things, employee theft relating to misappropriation of funds by two now former employees over an eight year period beginning in 2006.