Investments (Tables)

9 Months Ended

Sep. 30, 2018

Investments [Abstract]

Investment Securities Stated at Fair Value

Assets or liabilities that have recurring fair value measurements are shown below as of September 30, 2018 and December 31, 2017:

As of September 30, 2018

			Fair Value Measurements at Reporting Date Using
	Total as of		Quoted Prices in Active Markets for Identical Assets		Significant  Other Observable		Significant Unobservable Inputs
Description	September 30, 2018		(Level 1)		(Level 2)		(Level 3)
Cash & Cash Equivalents	$	194,017,041	$	194,017,041	$	—	$	—
Short-Term Investments:
Certificate of Deposit	130,000,000		130,000,000		—		—
Corporate Bonds	4,994,018		—		4,994,018		—
Government Securities	6,691,949		—		6,691,949		—
Other	1,937,574		1,937,574		—		—
Long-Term Investments:
Corporate Bonds	62,393,073		—		62,393,073		—
Government Securities	58,331,619		—		58,331,619		—
Common Stocks	40,000		40,000		—		—
Municipal Bonds	$	17,666,818	$	17,666,818	$	—	$	—
Total	$	476,072,092	$	343,661,433	$	132,410,659	$	—

As of December 31, 2017

			Fair Value Measurements at Reporting Date Using
	Total as of		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
Description	December 31, 2017		(Level 1)		(Level 2)		(Level 3)
Cash & Cash Equivalents	$	569,734,496	$	569,734,496	$	—	$	—
Short-Term Investments:
Certificate of Deposit	130,000,000		130,000,000		—		—
Government Securities	9,011,130		—		9,011,130		—
Mutual Funds	393,581		—		393,581		—
Corporate Bonds	12,944,999		—		12,944,999		—
Other	188,344		188,344		—		—
Long-Term Investments:
Corporate Bonds	3,018,720		—		3,018,720		—
Common Stocks	15,703,371		15,703,371		—		—
Mutual Funds	34,681,337		34,681,337		—		—
Preferred Stock	1,178,991		1,178,991		—		—
Total	$	776,854,969	$	751,486,539	$	25,368,430	$	—

Schedule of Amortized Cost, Unrealized Gains And Losses, And Market Value of Investment Securities

The amortized cost, unrealized gains and losses, and market value of investment securities are shown as of September 30, 2018, and December 31, 2017

As of September 30, 2018:

			Unrealized
	Cost		Gains		Losses		Market Value
Short-Term Investments:
Certificate of Deposit	$	130,000,000	$	—	$	—	$	130,000,000
Government Securities	6,699,555		—		(7,606)		6,691,949
Corporate Bonds	4,998,499		—		(4,481)		4,994,018
Other	1,937,574		—		—		1,937,574
Long-Term Investments:
Corporate Bonds	62,619,934		56		(226,917)		62,393,073
Government Securities	58,671,384		—		(339,765)		58,331,619
Common Stocks	40,000		—		—		40,000
Municipal Bonds	17,841,486		—		(174,668)		17,666,818
Total	$	282,808,432	$	56	$	(753,437)	$	282,055,051

As of December 31, 2017: 

			Unrealized
	Cost		Gains		Losses		Market Value
Short-Term Investments:
Certificate of Deposit	$	130,000,000	$	—	$	—	$	130,000,000
Government Securities	9,024,777		—		(13,647)		9,011,130
Mutual Funds	392,482		1,575		(476)		393,581
Corporate Bonds	12,952,229		—		(7,230)		12,944,999
Other	188,344		—		—		188,344
Long-Term Investments:
Corporate Bonds	3,022,994		—		(4,274)		3,018,720
Common Stocks	10,897,219		5,079,815		(273,663)		15,703,371
Mutual Funds	29,306,540		5,440,344		(65,547)		34,681,337
Preferred Stock	1,141,458		40,533		(3,000)		1,178,991
Total	$	196,926,043	$	10,562,267	$	(367,837)	$	207,120,473

Schedule of Unrealized Loss on Investments

Unrealized losses on investments as of September 30, 2018, are as follows:

	Aggregate Unrealized Losses		Aggregate Fair Value
Less than one year	$	753,437	$	148,084,928
Greater than one year	—		—
Total	$	753,437	$	148,084,928

Unrealized losses on investments as of December 31, 2017, are as follows: 

	Aggregate Unrealized Losses		Aggregate Fair Value
Less than one year	$	263,655	$	31,223,557
Greater than one year	104,182		285,077
Total	$	367,837	$	31,508,634

Investments Classified by Contractual Maturity Date

Fixed income securities as of September 30, 2018 have contractual maturities as follows:

Due within one year	$	141,685,968
Due between one and five years	129,595,580
Due over five years	8,795,930
	$	280,077,478