Investments (Tables)

9 Months Ended

Sep. 30, 2019

Investments [Abstract]

Investment Securities Stated at Fair Value

Assets or liabilities that have recurring fair value measurements are shown below as of September 30, 2019 and December 31, 2018:

As of September 30, 2019:

			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	September 30, 2019		(Level 1)		(Level 2)		(Level 3)
Cash & Cash Equivalents	$	260,151,083	$	260,151,083	$	—	$	—
Short-Term Investments:
Certificate of Deposit	150,299,384		150,299,384		—		—
Government Securities	38,163,353		—		38,163,353		—
Corporate Bonds	16,050,560		—		16,050,560		—
Municipal Bonds	1,671,264		—		1,671,264		—
Other	971,726		971,726		—		—
Long-Term Investments:
Corporate Bonds	42,320,659		—		42,320,659		—
Municipal Bonds	40,467,299		—		40,467,299		—
Government Securities	11,637,510		—		11,637,510		—
Total	$	561,732,838	$	411,422,193	$	150,310,645	$	—

As of December 31, 2018:

			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, 2018		(Level 1)		(Level 2)		(Level 3)
Cash & Cash Equivalents	$	217,025,278	$	217,025,278	$	—	$	—
Short-Term Investments:
Certificate of Deposit	150,299,384		150,299,384		—		—
Government Securities	9,176,227		—		9,176,227		—
Corporate Bonds	6,967,700		—		6,967,700		—
Other	2,219,688		2,219,688		—		—
Long-Term Investments:
Corporate Bonds	60,369,930		—		60,369,930		—
Municipal Bonds	18,025,432		—		18,025,432		—
Government Securities	56,483,720		—		56,483,720		—
Total	$	520,567,359	$	369,544,350	$	151,023,009	$	—

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, 2019 and December 31, 2018:

As of September 30, 2019:

			Unrealized
	Cost		Gains		Losses		Market Value
Short-Term Investments:
Certificate of Deposit	$	150,299,384	$	—	$	—	$	150,299,384
Government Securities	38,067,382		97,271		(1,300)		38,163,353
Municipal Bonds	1,673,133		13,163		(15,032)		1,671,264
Corporate Bonds	15,955,794		94,766		—		16,050,560
Other	971,726		—		—		971,726
Long-Term Investments:
Corporate Bonds	41,191,483		1,130,771		(1,595)		42,320,659
Municipal Bonds	39,170,735		1,296,564		—		40,467,299
Government Securities	11,539,947		97,563		—		11,637,510
Total	$	298,869,584	$	2,730,098	$	(17,927)	$	301,581,755

As of December 31, 2018: 

			Unrealized
	Cost		Gains		Losses		Market Value
Short-Term Investments:
Certificate of Deposit	$	150,299,384	$	—	$	—	$	150,299,384
Government Securities	9,186,586		—		(10,359)		9,176,227
Corporate Bonds	6,981,305		—		(13,605)		6,967,700
Other	2,219,688		—		—		2,219,688
Long-Term Investments:
Corporate Bonds	60,659,498		50,340		(339,908)		60,369,930
Municipal Bonds	17,840,518		184,914		—		18,025,432
Government Securities	56,280,552		205,553		(2,385)		56,483,720
Total	$	303,467,531	$	440,807	$	(366,257)	$	303,542,081

Schedule of Unrealized Loss on Investments

Unrealized losses on investments as of September 30, 2019, are as follows:

	Aggregate Unrealized Losses		Aggregate Fair Value
Less than one year	$	17,927	$	10,055,721
Greater than one year	—		—
Total	$	17,927	$	10,055,721

Unrealized losses on investments as of December 31, 2018, are as follows: 

	Aggregate Unrealized Losses		Aggregate Fair Value
Less than one year	$	365,824	$	68,722,980
Greater than one year	433		3,000,000
Total	$	366,257	$	71,722,980

Investments Classified by Contractual Maturity Date

Fixed income securities as of September 30, 2019 have contractual maturities as follows:

Due within one year	$	206,184,561
Due between one and five years	59,332,380
Due over five years	35,093,088
	$	300,610,029