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, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Cost	$ 222,624,828	$ 98,427,114
Unrealized Gains	5,209,434	6,146,311
Unrealized Losses	(918,703)	(4,869,531)
Market Value	226,915,559	99,703,894
Certificates of Deposit
Schedule of Available-for-sale Securities [Line Items]
Cost	130,000,000
Unrealized Gains	0
Unrealized Losses	0
Market Value	130,000,000
Government Securities
Schedule of Available-for-sale Securities [Line Items]
Cost	14,003,644	3,013,482
Unrealized Gains	0	0
Unrealized Losses	(10,164)	(2,622)
Market Value	13,993,480	3,010,860
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
Mutual Funds
Schedule of Available-for-sale Securities [Line Items]
Cost	26,326,674
Unrealized Gains	27,459
Unrealized Losses	(237,452)
Market Value	26,116,681
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Cost	6,706,721	1,512,405
Unrealized Gains	0	0
Unrealized Losses	(8,339)	(390)
Market Value	6,698,382	1,512,015
Other
Schedule of Available-for-sale Securities [Line Items]
Cost	212,653	24,480
Unrealized Gains	0	0
Unrealized Losses	0	0
Market Value	212,653	24,480
Corporate Bond, Long-Term Investments
Schedule of Available-for-sale Securities [Line Items]
Cost	1,955,292
Unrealized Gains	0
Unrealized Losses	(6,736)
Market Value	1,948,556
Common Stocks
Schedule of Available-for-sale Securities [Line Items]
Cost	9,825,550	17,395,641
Unrealized Gains	3,349,962	4,078,912
Unrealized Losses	(326,505)	(1,019,749)
Market Value	12,849,007	20,454,804
Mutual Funds – Equity
Schedule of Available-for-sale Securities [Line Items]
Cost	27,329,164	76,481,106
Unrealized Gains	1,830,992	2,067,399
Unrealized Losses	(288,146)	(3,846,770)
Market Value	28,872,010	$ 74,701,735
Preferred Stock
Schedule of Available-for-sale Securities [Line Items]
Cost	745,462
Unrealized Gains	360
Unrealized Losses	(31,822)
Market Value	$ 714,000

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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