Consolidated Statements of Cash Flows (USD $)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 14,352,968	$ 12,402,441	$ 11,373,943
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation on furniture and equipment	330,971	326,529	268,572
Stock-based compensation	3,972,725	2,571,702	1,854,187
(Increase) decrease in accounts receivable	(1,600,620)	1,448,901	(4,804,446)
Change in deferred income taxes	(1,221,328)	(382,227)	1,438,658
Investment gain/loss, net	111,078	167,495	(4,055,840)
Increase in accrued liabilities	6,919,616	8,449,814	7,323,481
Other changes in assets and liabilities	(1,110,001)	148,913	3,599,790
Net cash provided by operating activities	21,755,409	25,133,568	16,998,345
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of furniture and equipment	(253,082)	(62,529)	(604,928)
Cost of investments purchased and other portfolio activity	(925,507)	(1,314,588)	(9,149,453)
Proceeds from sale of investments	4,133,000	6,050,000	13,960,937
Net cash provided by investing activities	2,954,411	4,672,883	4,206,556
CASH FLOWS FROM FINANCING ACTIVITIES:
Payment for repurchase of common shares	(1,072,908)
Payment of taxes withheld on employee stock transactions	(158,988)	(146,071)	(140,602)
Proceeds from common stock issuance	960,888	920,343	825,959
Payment of dividends	(14,971,570)	(36,318,391)	(26,165,624)
Net cash used in financing activities	(15,242,578)	(35,544,119)	(25,480,267)
CASH AND CASH EQUIVALENTS
Net change during the year	9,467,242	(5,737,668)	(4,275,366)
At beginning of year	5,775,526	11,513,194	15,788,560
At end of year	15,242,768	5,775,526	11,513,194
Supplemental cash flow information:
Interest paid	0	0	0
Income taxes paid	10,849,000	7,444,300	2,625,900
Supplemental disclosure of non-cash transactions:
Common stock issued as incentive compensation	$ 7,461,984	$ 5,003,146	$ 4,852,216

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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).