Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Cash flows from operating activities:
Net income	$ 1,911,950	$ 1,397,508
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	801,689	743,650
Gain from disposal of equipment	(116,721)	(57,500)
Deferred income taxes	40,000	(21,000)
Changes in operating assets and liabilities:
Accounts receivable, net	(1,670,471)	(1,054,767)
Inventories, net	41,851	(2,721)
Other current assets	72,085	(18,162)
Accounts payable	413,512	261,013
Accrued wages and salaries	555,361	472,762
Other accrued expenses	237,527	40,982
Unearned revenue and customer deposits	125,868	(26,030)
Net cash provided by operating activities	2,412,651	1,735,735
Cash flows from investing activities:
Capital expenditures	(2,751,108)	(580,032)
Proceeds from the sale of equipment	165,200	57,500
Proceeds from certificates of deposit	5,363,000	4,200,000
Purchases of certificates of deposit	(4,233,348)	(4,376,282)
Net cash used in investing activities	(1,456,256)	(698,814)
Cash flows from financing activities:
Cash dividends paid	(434,760)	(434,760)
Net cash used in financing activities	(434,760)	(434,760)
Net increase in cash and cash equivalents	521,635	602,161
Cash and cash equivalents at beginning of period	392,810	704,345
Cash and cash equivalents at end of period	914,445	1,306,506
Supplemental schedule of non-cash investing activities:
Capital expenditures in accounts payable	$ 9,212