CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Operating activities
Net loss	$ (7,342)	$ (7,853)
Adjustments to reconcile net loss to net cash provided by operating activities:
Provision for doubtful accounts	5,861	9,066
Depreciation	7,739	5,773
Stock-based compensation	2,505	2,656
Amortization of intangibles	1,737	568
Deferred income tax assets (liabilities)		(505)
Amortization of investment premium		268
Decrease in deferred rent	(258)	(546)
Changes in operating assets and liabilities:
Accounts receivable	(3,760)	(3,071)
Inventory	(520)	(296)
Prepaid expenses and other assets	(1,446)	(16)
Accounts payable	1,977	1,252
Accrued and other liabilities	551	(3,682)
Net cash provided by operating activities	7,044	3,614
Investing activities
Acquisition of business, net of cash acquired		(28,042)
Purchases of property and equipment	(4,863)	(4,357)
Purchases of short-term available-for-sale investments		(11,935)
Sale or maturity of short-term available-for-sale investments		39,636
Net cash used in investing activities	(4,863)	(4,698)
Financing activities
Proceeds from the exercise of employee stock options and employee stock purchase plan contributions	583	440
Principal payments on capital lease obligations	(42)
Net cash provided by financing activities	541	440
Net increase (decrease) in cash and cash equivalents	2,722	(644)
Cash and cash equivalents - beginning of period	18,298	18,531
Cash and cash equivalents - end of period	21,020	17,887
Supplemental disclosure of cash flow information
Cash paid for taxes	105	130
Capital lease obligations	$ 695