Goodwill and Intangibles - Changes in Carrying Amount of Goodwill and Other Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Feb. 28, 2014	Feb. 28, 2013	Feb. 28, 2014	Feb. 28, 2013
Goodwill [Roll Forward]
Balance as of June 1, 2013 (net of amortization)			$ 3,109
Additions			0
Balance as of February 28, 2014	3,109		3,109
Customer Relationships [Roll Forward]
Amortization	(41)	(41)	(123)	(123)
Balance as of February 28, 2014	503		503
Goodwill and Other Intangible Assets [Roll Forward]
Balance as of June 1, 2013 (net of amortization)			4,146
Additions			0
Amortization	(41)	(41)	(123)	(123)
Balance as of February 28, 2014	4,023		4,023
Customer relationships
Customer Relationships [Roll Forward]
Balance as of June 1, 2013 (net of amortization)			626
Additions			0
Amortization			(123)
Balance as of February 28, 2014	503		503
Goodwill and Other Intangible Assets [Roll Forward]
Amortization			(123)
Trade name
Trade Name [Roll Forward]
Balance as of June 1, 2013 (net of amortization)			411
Additions			0
Balance as of February 28, 2014	$ 411		$ 411