Summary of Significant Accounting and Reporting Policies (Schedule of Amortized Cost, Unrealized Gains And Losses, And Market Value Of Investment Securities) (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Cost	$ 196,926,043	$ 222,624,828
Unrealized Gains	10,562,267	5,209,434
Unrealized Losses	(367,837)	(918,703)
Market Value	207,120,473	226,915,559
Certificates of Deposit
Schedule of Available-for-sale Securities [Line Items]
Cost	130,000,000	130,000,000
Unrealized Gains	0	0
Unrealized Losses	0	0
Market Value	130,000,000	130,000,000
Government Securities
Schedule of Available-for-sale Securities [Line Items]
Cost	9,024,777	14,003,644
Unrealized Gains	0	0
Unrealized Losses	(13,647)	(10,164)
Market Value	9,011,130	13,993,480
Mutual Funds
Schedule of Available-for-sale Securities [Line Items]
Cost	392,482	26,326,674
Unrealized Gains	1,575	27,459
Unrealized Losses	(476)	(237,452)
Market Value	393,581	26,116,681
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Cost	12,952,229	6,706,721
Unrealized Gains	0	0
Unrealized Losses	(7,230)	(8,339)
Market Value	12,944,999	6,698,382
Other
Schedule of Available-for-sale Securities [Line Items]
Cost	188,344	212,653
Unrealized Gains	0	0
Unrealized Losses	0	0
Market Value	188,344	212,653
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Cost	3,022,994	1,955,292
Unrealized Gains	0	0
Unrealized Losses	(4,274)	(6,736)
Market Value	3,018,720	1,948,556
Common Stocks
Schedule of Available-for-sale Securities [Line Items]
Cost	10,897,219	9,825,550
Unrealized Gains	5,079,815	3,349,962
Unrealized Losses	(273,663)	(326,505)
Market Value	15,703,371	12,849,007
Mutual Funds – Equity
Schedule of Available-for-sale Securities [Line Items]
Cost	29,306,540	27,329,164
Unrealized Gains	5,440,344	1,830,992
Unrealized Losses	(65,547)	(288,146)
Market Value	34,681,337	28,872,010
Preferred Stock
Schedule of Available-for-sale Securities [Line Items]
Cost	1,141,458	745,462
Unrealized Gains	40,533	360
Unrealized Losses	(3,000)	(31,822)
Market Value	$ 1,178,991	714,000
Government Securities
Schedule of Available-for-sale Securities [Line Items]
Cost		5,519,668
Unrealized Gains		661
Unrealized Losses		(9,539)
Market Value		$ 5,510,790