Severance Costs (Detail) - USD ($) $ in Thousands			3 Months Ended		6 Months Ended
	May. 28, 2015	Dec. 03, 2013	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Chief Executive Officer [Member]
Restructuring Cost and Reserve [Line Items]
Severance costs		$ 915
Chief Financial Officer [Member]
Restructuring Cost and Reserve [Line Items]
Severance costs	$ 941		$ 710		$ 710
Severance [Member]
Restructuring Reserve [Roll Forward]
Balance at beginning of period			36	$ 699	89	$ 1,142
Provision for additional expense			722	184	722	313
Payments and adjustments			(59)	(336)	(112)	(908)
Balance at end of period			$ 699	547	$ 699	547
Severance [Member] | Chief Executive Officer [Member]
Restructuring Cost and Reserve [Line Items]
Severance payments				$ 104		$ 301