CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income	$ 4,444,000us-gaap_NetIncomeLoss	$ 5,967,000us-gaap_NetIncomeLoss
Income (loss) from discontinued operations, net of tax	28,000	(578,000)
Income from continuing operations	4,416,000	6,545,000
Adjustments to reconcile net income to net cash provided by operating activities from continuing operations:
Depreciation and amortization	1,877,000	2,029,000
Realized (gain) loss on investment securities, net	(118,000)us-gaap_GainLossOnSaleOfInvestments	(188,000)us-gaap_GainLossOnSaleOfInvestments
Share-based compensation	529,000us-gaap_ShareBasedCompensation	774,000us-gaap_ShareBasedCompensation
Deferred income taxes	(154,000)us-gaap_DeferredIncomeTaxExpenseBenefit	(381,000)us-gaap_DeferredIncomeTaxExpenseBenefit
(Gain) on disposal of fixed assets	0us-gaap_GainLossOnDispositionOfAssets	(32,000)us-gaap_GainLossOnDispositionOfAssets
Changes in assets and liabilities which provided (used) cash:
Accounts receivable	(656,000)	(204,000)
Inventory	1,549,000us-gaap_IncreaseDecreaseInInventories	2,120,000us-gaap_IncreaseDecreaseInInventories
Prepaid expenses and other current assets	16,000	(67,000)
Other assets	335,000	2,000
Accounts payable and accrued expenses	3,615,000	(82,000)
Income taxes	1,202,000	610,000
Net cash provided by operating activities- continuing operations	12,611,000	11,126,000
Net cash used in operating activities- discontinued operations	(2,513,000)	(505,000)
Net cash provided by operating activities	10,098,000	10,621,000
Cash Flow from Investing Activities:
Sale of investment securities	2,022,000	3,572,000
Purchase of investment securities	(1,526,000)us-gaap_PaymentsToAcquireInvestments	(7,943,000)us-gaap_PaymentsToAcquireInvestments
Purchase of property and equipment	(907,000)	(1,182,000)
Net cash used in investing activities- continuing operations	(411,000)	(5,553,000)
Net cash used in investing activities- discontinued operations	0	(42,000)
Net cash used in investing activities	(411,000)	(5,595,000)
Cash Flow from Financing Activities:
Repayment of long-term debt and capital leases	(57,000)us-gaap_RepaymentsOfLongTermDebt	(55,000)us-gaap_RepaymentsOfLongTermDebt
Decrease in note receivable	45,000	7,000
Net shares repurchased for employee taxes	(875,000)	0
Excess tax benefits from share-based compensation	165,000	0
Net cash used in financing activities- continuing operations	(722,000)	(48,000)
Net cash used in financing activities- discontinued operations	0	0
Net cash used in financing activities	(722,000)	(48,000)
NET CHANGE IN CASH AND CASH EQUIVALENTS	8,965,000	4,978,000
Cash and cash equivalents - beginning of the period	24,459,000	36,382,000
Cash and cash equivalents - end of period	33,423,000	41,360,000
Supplemental disclosure of cash flow information:
Interest paid	10,000us-gaap_InterestPaid	53,000us-gaap_InterestPaid
Income taxes paid	$ 295,000us-gaap_IncomeTaxesPaid	$ 2,687,000us-gaap_IncomeTaxesPaid

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.