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, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Cost	$ 303,467,531	$ 196,926,043
Unrealized Gains	440,807	10,562,267
Unrealized Losses	(366,257)	(367,837)
Market Value	303,542,081	207,120,473
Certificates of Deposit
Debt Securities, Available-for-sale [Line Items]
Cost	150,299,384	130,000,000
Unrealized Gains	0	0
Unrealized Losses	0	0
Market Value	150,299,384	130,000,000
Government Securities
Debt Securities, Available-for-sale [Line Items]
Cost	9,186,586	9,024,777
Unrealized Gains	0	0
Unrealized Losses	(10,359)	(13,647)
Market Value	9,176,227	9,011,130
Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	17,840,518
Unrealized Gains	184,914
Unrealized Losses	0
Market Value	18,025,432
Mutual Funds
Debt Securities, Available-for-sale [Line Items]
Cost		392,482
Unrealized Gains		1,575
Unrealized Losses		(476)
Market Value		393,581
Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	6,981,305	12,952,229
Unrealized Gains	0	0
Unrealized Losses	(13,605)	(7,230)
Market Value	6,967,700	12,944,999
Other
Debt Securities, Available-for-sale [Line Items]
Cost	2,219,688	188,344
Unrealized Gains	0	0
Unrealized Losses	0	0
Market Value	2,219,688	188,344
Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	60,659,498	3,022,994
Unrealized Gains	50,340	0
Unrealized Losses	(339,908)	(4,274)
Market Value	60,369,930	3,018,720
Common Stocks
Debt Securities, Available-for-sale [Line Items]
Cost	0	10,897,219
Unrealized Gains	0	5,079,815
Unrealized Losses	0	(273,663)
Market Value	0	15,703,371
Mutual Funds – Equity
Debt Securities, Available-for-sale [Line Items]
Cost		29,306,540
Unrealized Gains		5,440,344
Unrealized Losses		(65,547)
Market Value		34,681,337
Preferred Stock
Debt Securities, Available-for-sale [Line Items]
Cost		1,141,458
Unrealized Gains		40,533
Unrealized Losses		(3,000)
Market Value		$ 1,178,991
Government Securities
Debt Securities, Available-for-sale [Line Items]
Cost	56,280,552
Unrealized Gains	205,553
Unrealized Losses	(2,385)
Market Value	56,483,720
Government Securities
Debt Securities, Available-for-sale [Line Items]
Cost	0
Unrealized Gains	0
Unrealized Losses	0
Market Value	$ 0

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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 investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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