Subsequent Events - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended	1 Months Ended
Apr. 27, 2013 Restricted Stock Units (RSUs)	Apr. 28, 2012 Restricted Stock Units (RSUs)	Apr. 30, 2011 Restricted Stock Units (RSUs)	Jul. 08, 2013 Subsequent Event Chief Executive Officer Termination Benefits	Jul. 08, 2013 Subsequent Event Chief Executive Officer Termination Benefits Restricted Stock Units (RSUs)
Subsequent Event [Line Items]
Cash Severance				$ 3,650
Restricted stock units vested	13,000	0	0		275,846
Restricted stock units vested, aggregate value	$ 205				$ 4,871
Closing price of the Company's common stock				$ 17.66

The charge against earnings in the period for known and estimated costs of termination benefits provided to current employees that are involuntarily terminated under a benefit arrangement associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding costs or losses pertaining to an entity newly acquired in a business combination or a discontinued operation as defined by generally accepted accounting principles and costs associated with one-time termination benefits.

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+ Details