Deferred Tax Assets and Deferred Tax Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Schedule of Deferred Tax Assets and Liabilities [Line Items]
Accounts receivable	$ 389	$ 300
Inventory	2,643	2,789
Accruals not currently deductible for tax purposes	10,054	10,831
Net operating loss and credit carryforwards	2,669	11,403
Capital loss carryforward	3,105	3,105
Depreciation	2,870	4,553
Equity compensation	3,155	2,280
Asset impairments	1,021	1,021
Purchased intangibles	1,396	339
Other, net	3,604	3,090
Gross deferred tax assets	30,906	39,711
Valuation allowance	(4,990)	(4,632)
Total deferred tax assets	25,916	35,079
Depreciation	(1,252)	(918)
Purchased intangible assets	(692)	(674)
Total deferred tax liabilities	(1,944)	(1,592)
Net deferred tax assets	$ 23,972	$ 33,487