Shareholder Right Plan - Additional Information (Detail) (USD $)	12 Months Ended	1 Months Ended
	Jun. 30, 2012	Dec. 06, 2004 Stockholder Rights Plan
Shareholder Rights [Line Items]
Stock purchase rights distributed for each outstanding shares of common stock		1
Shareholder rights plan, exercise price	75
Stock purchase rights, redemption price per right	$ 0.001
Stock purchase rights, expiration date	Dec. 06, 2014