Organization and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014 Customer Depository Distributor Segment Source	Dec. 31, 2013 Customer Distributor	Dec. 31, 2012 Distributor
Summary Of Significant Accounting Policy [Line Items]
Number of revenue sources	2
Note receivable in term	5 years
Company receive payment	30 days
Accounts and notes receivable related to purchases	$ 0	$ 0
Advertising Cost	300,000	200,000	200,000
Warranty period	1 year
Research and development costs	14,885,000	9,888,000	8,139,000
Allowance for doubtful accounts	251,000	200,000
Reserve for bad debt expense	142,000	24,000	(242,000)
Number of depository institutions	3
Aggregate balances in accounts	48,400,000
Number of customers	0
Unaffiliated distributors	1	1	1
Percentage of total net sales represented	10.00%	10.00%	10.00%
Accounts and notes receivable by customers one	13.40%	17.40%
Unaffiliated customers	1	1
Corporate owned life insurance policies fair value	1,100,000	400,000
Number of reportable segments of company	2
Implied volatility period of publicly traded options	1 year
Sales
Summary Of Significant Accounting Policy [Line Items]
Percentage of total net sales represented		12.20%	12.80%
Minimum
Summary Of Significant Accounting Policy [Line Items]
Service term for services purchased	1 year
Contractual Period of entities assurance program	3 years
Maximum
Summary Of Significant Accounting Policy [Line Items]
Service term for services purchased	5 years
Contractual Period of entities assurance program	5 years
Evidence. Com
Summary Of Significant Accounting Policy [Line Items]
Amortization of capitalized software development costs		$ 600,000	$ 1,200,000
Extended Product Warranty | Minimum
Summary Of Significant Accounting Policy [Line Items]
Period of extended warranty after expiration of standard warranty	1 year
Extended Product Warranty | Maximum
Summary Of Significant Accounting Policy [Line Items]
Period of extended warranty after expiration of standard warranty	5 years