CONDENSED STATEMENTS OF CASH FLOWS - USD ($)	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 1,326,237	$ 2,529,978
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	1,102,112	751,306
Stock-based compensation	514,422	448,417
Changes in assets and liabilities:
Accounts receivable	(1,375,031)	(1,388,452)
Prepaid expenses, other current assets, and income tax receivable	787,769	286,221
Accounts payable	(209,627)	172,696
Accrued expenses	43,335	(667,621)
Deferred income taxes	(225,138)	(176,648)
Net cash provided by operating activities	1,964,079	1,955,897
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of equipment and leasehold improvements	(1,091,683)	(6,993,673)
Cost of internally developed software	(310,981)	(321,394)
Other assets	(23,011)	(202,283)
Net cash used in investing activities	(1,425,675)	(7,517,350)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from exercise of stock options	91,556	47,564
Proceeds from issuance of stock, net of tax withholding	(140,175)	(36,968)
Proceeds from equipment financing	1,098,539	6,999,626
Payments of equipment financing	(1,049,944)	(401,562)
Cash dividends paid	(2,428,639)	(2,406,007)
Net cash provided by (used in) financing activities	(2,428,663)	4,202,653
Net decrease in cash and cash equivalents	(1,890,259)	(1,358,800)
Cash and cash equivalents, beginning of period	3,612,153	3,970,512
Cash and cash equivalents, end of period	1,721,894	2,611,712
Supplemental Disclosures of Cash Flow Information:
Cash paid for income taxes	2,870	461,920
Cash paid for interest	94,385	42,285
Purchases of equipment through accrued liabilities	$ 5,037	$ 191,566