Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
OPERATING ACTIVITIES
Net income (loss)	$ 6,148	$ 1,753	$ (2,306)
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	2,808	3,195	3,796
Amortization	912	886	1,312
Loss on equipment disposals/impaired assets	56	20	94
Gain on revaluation of ACT liability	(758)	(768)	(781)
Unrealized holding gain on marketable security	(21)
Allowance for doubtful accounts	348	12	(10)
Deferred income tax	793	(588)	(1,492)
Stock compensation expense	2,810	4,274	6,097
Changes in operating assets and liabilities:
Accounts receivable	(13,279)	(3,377)	5,498
Inventories	504	(354)	563
Prepaid expenses, other current assets and other noncurrent assets	(723)	(27)	3,293
Accounts payable	2,914	1,765	(2,372)
Accrued liabilities and other noncurrent liabilities	2,346	5,379	(113)
Other		20	34
Net cash provided by operating activities	4,858	12,190	13,613
INVESTING ACTIVITIES
Decrease (increase) in restricted cash		200	(200)
Purchases of property, equipment and patents	(2,408)	(2,206)	(2,004)
Proceeds from the sale of equipment	2
Acquisitions of businesses			(20,185)
Net cash used in investing activities	(2,406)	(2,006)	(22,389)
FINANCING ACTIVITIES
(Payments) / proceeds from debt	(1,162)	(737)	737
Proceeds from exercises of stock options	376	10	605
Excess tax benefit from exercises of stock options	77		78
Reclassification of liability award			90
Repurchases of common stock	(4,111)
Other		(5)
Net cash (used in) provided by financing activities	(4,820)	(732)	1,510
Effect of exchange rate fluctuations on cash	73	107	82
Net increase (decrease) in cash and cash equivalents	(2,295)	9,559	(7,184)
Cash and cash equivalents at beginning of year	30,524	20,965	28,149
Cash and cash equivalents at end of year	28,229	30,524	20,965
Non-cash activities:
(Decrease) increase in contingent consideration payable	(758)	(768)	2,307
Cash paid for:
Interest	148	143	120
Income taxes paid	$ 5,187	$ 297	$ 195