Consolidated Statements Of Cash Flows (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Cash flows from operating activities:
Net income	$ 2,365,639	$ 1,094,989
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	571,967	587,750
Loss (gain) on sale of investments, net	(64,335)	(17,985)
Deferred income taxes	(192,090)	(185,805)
Bad Debt Expense	51,819	6,384
(Increase) decrease in operating assets:
Accounts receivable	(3,244,063)	(526,979)
Other receivables	3,660	68,267
Inventories	(1,141,713)	(250,982)
Refundable income taxes	0	41,316
Prepaid expenses and other current assets	4,311	39,750
Increase (decrease) in operating liabilities:
Accounts payable	2,209,076	211,227
Accrued expenses	42,206	201,462
Income taxes payable	208,282	279,402
Net cash provided by operating activities	814,759	1,548,796
Cash flows from investing activities:
Purchases of investments	(1,271,516)	(318,123)
Proceeds from sale of investments	1,170,271	404,028
Redemption of certificates of deposits	200,000	0
Purchases of property and equipment	(324,608)	(231,243)
Net cash used in investing activities	(225,853)	(145,338)
Cash flows from financing activities:
Checks written in excess of bank balances	0	(258,594)
Purchases of treasury stock	0	(176,606)
Repayment of notes payable	(135,175)	(926,869)
Net cash used in financing activities	(135,175)	(1,362,069)
Net (decrease) increase in cash and cash equivalents	453,731	41,389
Cash and cash equivalents at the beginning of the period	2,286,226	1,115,150
Cash and cash equivalents at the end of the period	$ 2,739,957	$ 1,156,539