Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2012

Summary of Significant Accounting Policies [Abstract]

Components of cash and cash equivalents and short-term investments

The components of our cash and cash equivalents and short-term investments as of December 31, 2012 and 2011are as follows:

	December 31,		December 31,
	2012		2011
Cash and cash equivalents:
Cash and cash equivalents	$	55,116,328	$	63,077,178
Total cash and cash equivalents	$	55,116,328	$	63,077,178
Short-term investments:
Held-to-maturity (less than one year to maturity)	$	33,057,835	$	24,739,998
Total short-term investments	$	33,057,835	$	24,739,998

Components of marketable securities and other investments

The components of our marketable securities and other investments as of December 31, 2012 and 2011 are as follows:

	December 31,		December 31,
	2012		2011
Marketable securities and other investments:
Held-to-maturity other investments	$	10,535,741		$	20,270,954
Auction-rate securities		997,349			997,823
Total marketable securities and other investments	$	11,533,090		$	21,268,777

Accounts receivable allowance activity

Accounts receivable allowance activity consisted of the following for the years ended December 31, 2012, 2011, and 2010, respectively.

At December 31,	2012			2011			2010
Balance at beginning of year	$	796,610		$	833,199		$	786,797
Additions		814,761			308,302			407,961
Write-offs/deductions/recoveries		(622,664	)		(344,891	)		(361,559	)
Balance at end of year	$	988,707		$	796,610		$	833,199

Inventories

At December 31, 2012 and 2011, inventories consisted of the following:

At December 31,	2012		2011
Raw materials	$	8,475,918	$	10,068,589
Work in process		1,795,986		1,217,968
Finished goods		11,313,003		9,889,197
Total	$	21,584,907	$	21,175,754

Property and equipment

At December 31, 2012 and 2011, property and equipment consisted of the following:

					Estimated
At December 31,	2012		2011		Useful Life
Land	$	10,680,000	$	10,680,000
Building		24,505,574		24,505,574	39 years
Machinery and equipment		3,496,347		3,231,920	3 - 7 years
Furniture and fixtures		6,210,158		5,836,744	7 years
Leasehold improvements		96,100		99,243	Shorter of estimated useful life or term of lease
		44,988,179		44,353,481
Less accumulated depreciation		9,103,151		7,639,903
Total	$	35,885,028	$	36,713,578

Change in product warranty accrual

The following table provides the detail of the change in our product warranty accrual, which is a component of accrued liabilities on the consolidated balance sheets for the years ended December 31, 2012 and 2011.

At December 31,	2012			2011
Warranty accrual, beginning of year	$	785,412		$	529,374
Charged to costs and expenses relating to new sales		2,026,290			1,226,017
Costs of product warranty claims\change in estimate		(1,826,130	)		(969,979	)
Warranty accrual, end of year	$	985,572		$	785,412

Reconciliation of basic and diluted weighted average shares

The reconciliation of basic and diluted weighted average shares outstanding is as follows:

At December 31,	2012		2011		2010
Basic weighted average common shares outstanding		18,863,708		18,695,612		18,548,548
Potential common shares pursuant to stock options, SARs and RSAs		-		246,404		-
Diluted weighted average common shares outstanding		18,863,708		18,942,016		18,548,548

Stock-based compensation

During the years ended December 31, 2012, 2011, and 2010, we recognized stock-based compensation expense as follows:

	For the year ended December 31,
(in millions)	2012		2011		2010
Cost of professional product revenues	$	0.2	$	0.2	$	0.2
Cost of service revenues		0.1		0.2		0.2
Research and development expense		0.9		1.5		1.8
Selling and marketing expense		0.8		1.0		0.9
General and administrative expense		0.6		0.7		0.7
	$	2.6	$	3.6	$	3.8

Weighted-average assumptions of options

We use the Black-Scholes option pricing model to estimate the fair value of stock option and SAR grants. Key input assumptions used to estimate the fair value of stock options and SARs include the exercise price of the award, the expected option term, the expected volatility of our stock over the option or SARs expected term, the risk-free interest rate over the option or SARs expected term and our expected annual dividend yield. Expected volatilities are based on historical volatilities of our common stock; the expected life represents the weighted average period of time that options or SARs granted are expected to be outstanding giving consideration to vesting schedules and our historical exercise patterns; and the risk-free rate is based on the U.S. Treasury yield curve in effect at the time of grant for periods corresponding with the expected life of the option or SAR. Our assumed dividend yield of zero is based on the fact that we have never paid cash dividends and currently have no intention to pay cash dividends. The fair value of each award was estimated on the grant date using the Black-Scholes option-pricing model with the following weighted-average assumptions:

Year ended December 31,	2012		2011		2010
Risk-free interest rate		-		-		1.66%
Expected dividend yield		-		-		-
Expected lives		-		-		3.0 years
Expected volatility		-		-		60%
Grant date fair value of awards granted during period		-		-		$6.17

Fair value on a recurring basis

Assets and liabilities measured at fair value on a recurring basis are categorized in the tables below based upon the lowest level of significant input to the valuations. The following table presents our assets measured at fair value on a recurring basis as of December 31, 2012 and December 31, 2011.

Assets	Fair Value as of December 31, 2012
(in thousands)	Level 1		Level 2		Level 3		Total
Cash and cash equivalents	$	55,116	$	-	$	-	$	55,116
Short-term investments*		33,058		-		-		33,058
Other investments*		10,536		-		-		10,536
Auction-rate municipal securities		-		-		997		997
Total	$	98,710	$	-	$	997	$	99,707

* The amortized cost of these investments approximates fair market value.

Assets	Fair Value as of December 31, 2011
(in thousands)	Level 1		Level 2		Level 3		Total
Cash and cash equivalents	$	63,077	$	-	$	-	$	63,077
Short-term investments*		24,740		-		-		24,740
Other investments*		20,271		-		-		20,271
Auction-rate municipal securities		-		-		998		998
Total	$	108,088	$	-	$	998	$	109,086

* The amortized cost of these investments approximates fair market value.

Level 3 gains and losses

The table presented below summarizes the change in balance sheet carrying values associated with Level 3 financial instruments for the year ended December 31, 2012.

	Auction-rate
(In thousands)	municipal securities			Total
Balance at December 31, 2011	$	998		$	998
Net transfers in/(out) of Level 3		-			-
Purchases		-			-
Settlements (at par)		-			-
Gains
Realized		-			-
Unrealized		-			-
Losses
Realized		-			-
Unrealized		(1	)		(1	)
Balance at December 31, 2012	$	997		$	997

Components of accumulated other comprehensive loss

The components of accumulated other comprehensive loss as of December 31, 2012 and 2011 are as follows:

At December 31,	2012			2011
Unrealized loss on marketable securities, net of taxes	$	(185,661	)	$	(192,861	)
Foreign currency translation adjustment		(67,230	)		(70,988	)
Total accumulated other comprehensive loss	$	(252,891	)	$	(263,849	)