Supplemental Balance Sheet Information (Tables)

3 Months Ended

Mar. 31, 2013

Supplemental Balance Sheet Information [Abstract]

Accounts receivables

Receivables

Accounts receivable consist of the following (in thousands):

	March 31, 2013		December 31, 2012
Trade receivables	$	18,006	$	18,350
Allowance for doubtful accounts		446		488
	$	17,560	$	17,862

Schedule of inventory

Inventory

We state inventories at the lower of cost or market, using the first-in-first-out-method (in thousands):

	March 31, 2013			December 31, 2012
Raw materials	$	7,089		$	6,983
Work in process		2,527			2,429
Finished goods		1,641			3,516
Allowances for obsolescence		(1,827	)		(1,849	)
	$	9,430		$	11,079

Property and Equipment

Property and Equipment

Property and equipment consist of the following (in thousands):

	March 31, 2013			December 31, 2012
Equipment	$	10,400		$	10,298
Demonstration units		1,810			1,828
Computers and purchased software		4,303			4,251
Furniture and fixtures		457			444
Leasehold improvements		7,753			7,662
Construction in progress		107			188
		24,830			24,671
Accumulated depreciation		(22,403	)		(22,213	)
	$	2,427		$	2,458

Accrued Expenses

Accrued Expenses

Accrued expenses consist of the following (in thousands):

	March 31, 2013		December 31, 2012
Compensation and benefits	$	1,591	$	2,199
Warranty liability		699		694
Property, income, state, sales and franchise tax		656		320
Professional fees		558		502
Other		1,421		1,233
	$	4,925	$	4,948

Changes in warranty liability

Changes in our warranty liability are presented in the following table (in thousands):

Balance at December 31, 2012	$	755
Warranty expense		182
Warranty charges incurred		(170	)
Balance at March 31, 2013	$	767
Warranty liability included in accrued expenses	$	699
Long-term warranty liability		68
Balance at March 31, 2013	$	767