Income Taxes - Components of Deferred Income Tax Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 13, 2013	Dec. 31, 2012
Deferred income tax assets:
Net operating loss carryforward	$ 513		$ 47
Deferred warranty revenue	2,837		1,759
Inventory reserve	389		906
Non-qualified and non-employee stock option expense	3,518		3,682
Capitalized research and development	6,588		8,191
Alternative minimum tax carryforward	1,466		1,406
Research and development tax credit carryforward	3,165		2,936
Deferred legal settlement	1,294		723
IRC section 481(a) adjustment-tangible property	1,316
Reserves, accruals, and other	2,066		2,156
Total deferred income tax assets	23,152		21,806
Deferred income tax liabilities:
Depreciation	(2,136)	(1,300)	(662)
Amortization	(236)		(142)
Total deferred income tax liabilities	(2,372)		(804)
Net deferred income tax assets	$ 20,780		$ 21,002