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:
Consolidated net income	$ 9,309	$ 33,539	$ 4,093
Adjustments to reconcile consolidated net income to net cash provided by operating activities:
Depreciation and amortization	11,005	10,222	10,198
Stock compensation expense	1,923	871	657
Increase (decrease) in long-term deferred revenue	350	(18)	1,078
Credit (gain) loss on available for sale securities	(302)	146	464
Deferred income taxes	148	(6,274)	(74)
Excess tax benefit of share-based compensation	(133)	(213)
Gain on disposal of equipment	(21)	(249)	(30)
Unrealized gain on trading securities		(970)	(1,268)
Unrealized loss on auction rate security rights		962	964
Severance charges			4,099
Change in current assets and liabilities, net	4,128	(21,122)	4,617
Net cash provided by operating activities	26,407	16,894	24,798
Investing activities:
Purchases of investments	(1,104)	(908)	(1,695)
Sales and maturities of investments	11,142	15,768	6,650
Additions to property, plant and equipment	(7,466)	(12,103)	(10,643)
Proceeds from sale of equipment	10	421	32
Change in restricted cash		415	322
(Increase) decrease in other assets	(55)	172	(572)
Net cash provided by (used in) investing activities	2,527	3,765	(5,906)
Financing activities:
Proceeds from issuance of Common Stock	452	1,104
Common Stock dividends paid	(6,272)	(12,506)
Noncontrolling interest dividends paid	(690)	(552)	(1,269)
Excess tax benefit of share-based compensation	133	213
Net cash used in financing activities	(6,377)	(11,741)	(1,269)
Effect of foreign exchange rates on cash	72	137	(38)
Net increase in cash and cash equivalents	22,629	9,055	17,585
Cash and cash equivalents at beginning of period	49,279	40,224	22,639
Cash and cash equivalents at end of period	71,908	49,279	40,224
Change in assets and liabilities:
Accounts receivable	7,546	(11,926)	2,148
Inventories, net	(162)	(13,928)	5,291
Other current assets	(224)	2,050	(2,065)
Accounts payable and accrued liabilities	(3,861)	3,881	2,550
Accrued severance charges		(259)	(3,840)
Accrual for litigation settlements			(162)
Income taxes payable	324	892	(1,164)
Deferred revenue	505	(1,832)	1,859
Change in current assets and liabilities, net	4,128	(21,122)	4,617
Supplemental disclosures:
Cash paid during the year for income taxes, net of refunds	$ 4,178	$ 1,113	$ 3,122

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).