Investments (Tables)

6 Months Ended

Jun. 30, 2015

Investments [Abstract]

Investment Securities Stated at Fair Value

Assets or liabilities that have recurring fair value measurements are shown below as of June 30, 2015, and December 31, 2014:

As of June 30, 2015:

			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	June 30, 2015		(Level 1)		(Level 2)		(Level 3)
Cash & Cash Equivalents	$	569,896,553	$	569,896,553	$	—	$	—
Short-Term Investments:
Other	454		454		—		—
Long-Term Investments:
Common Stocks	23,685,720		23,685,720		—		—
Mutual Funds – Equity	91,054,926		91,054,926		—		—
Total	$	684,637,653	$	684,637,653	$	—	$	—

As of December 31, 2014:

			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, 2014		(Level 1)		(Level 2)		(Level 3)
Cash & Cash Equivalents	$	497,429,804	$	497,429,804	$	—	$	—
Short-Term Investments:
Other	1,021		1,021		—		—
Long-Term Investments:
Common Stocks	24,648,451		24,648,451		—		—
Mutual Funds – Equity	89,994,116		89,994,116		—		—
Total	$	612,073,392	$	612,073,392	$	—	$	—

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 June 30, 2015, and December 31, 2014:

As of June 30, 2015:

			Unrealized
	Cost		Gains		Losses			Market Value
Short-Term Investments:
Other	$	454	$	—	$	—		$	454
Long-Term Investments:
Common Stocks	18,690,052		5,639,978		(644,310		)	23,685,720
Mutual Funds – Equity	82,894,342		8,824,766		(664,182		)	91,054,926
Total	$	101,584,848	$	14,464,744	$	(1,308,492	)	$	114,741,100

As of December 31, 2014:

			Unrealized
	Cost		Gains		Losses			Market Value
Short-Term Investments:
Other	$	1,021	$	—	$	—		$	1,021
Long-Term Investments:
Common Stocks	17,069,742		7,933,717		(355,008		)	24,648,451
Mutual Funds – Equity	80,852,329		9,922,204		(780,417		)	89,994,116
Total	$	97,923,092	$	17,855,921	$	(1,135,425	)	$	114,643,588

Schedule of Unrealized Loss on Investments

Unrealized losses on investments as of June 30, 2015, are as follows:

	Aggregate Unrealized Losses		Aggregate Fair Value
Less than one year	$	1,308,492	$	25,133,644

Unrealized losses on investments as of December 31, 2014, are as follows:

	Aggregate Unrealized Losses		Aggregate Fair Value
Less than one year	$	1,135,425	$	19,972,258