Condensed Consolidated Statements Of Cash Flows (USD $)	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 10,372,141	$ 7,745,647
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	1,571,423	1,418,065
Share-based compensation	413,332	39,093
Deferred income taxes	973,817	(474,900)
Goodwill impairment	1,271,986	0
Gain (loss) on sale of assets	4,674	(1,143)
Excess tax benefit from stock based payments	(23,227)
Changes in assets and liabilities:
Trade receivables	(3,664,939)	(5,315,719)
Inventories	(609,224)	302,888
Prepaid income taxes	(273,981)	337,274
Other assets	21,595	(508,666)
Accounts payable	(1,357,506)	(421,603)
Accrued compensation and benefits	(99,861)	56,473
Other accrued expenses	(288,821)	247,625
Income taxes payable	(59,368)	1,552,228
Net cash provided by operating activities	8,252,041	4,977,262
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(1,635,893)	(1,190,886)
Purchases of investments	(16,156,015)	(17,110,186)
Acquisition of business, net of cash acquired	(2,408,910)
Proceeds from the sale of fixed assets	8,055	27,593
Proceeds from the sale of investments	19,174,385	10,176,299
Net cash used in investing activities	(1,018,378)	(8,097,180)
CASH FLOWS FROM FINANCING ACTIVITIES:
Cash dividends paid	(3,795,989)	(3,598,544)
Mortgage principal payments	(296,844)	(277,300)
Proceeds from issuance of common stock	177,609	100,337
Excess tax benefit from stock based payments	23,227
Net cash used in financing activities	(3,891,997)	(3,775,507)
EFFECT OF FOREIGN EXCHANGE RATE CHANGES ON CASH	(44,619)	(31,841)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	3,297,047	(6,927,266)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	16,787,558	21,293,448
CASH AND CASH EQUIVALENTS AT END OF PERIOD	20,084,605	14,366,182
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Income taxes paid	6,996,908	3,473,805
Interest paid	121,615	153,249
Dividends declared not paid	1,269,155	1,259,940
Acquisition costs in accrued expenses	$ 1,681,367

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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).