Marketable Securities and Certificates of Deposit (Tables)

6 Months Ended

Jun. 30, 2018

Investments, Debt and Equity Securities [Abstract]

Unrealized Gain (Loss) on Investments

The amortized cost and estimated fair value of the Company's Marketable Securities as of June 30, 2018 and December 31, 2017 were as follows:

	June 30, 2018								December 31, 2017
	Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Securities Investments - Debt Securities	$	3,645	$	11	$	—	$	3,656	$	1,806	$	—	$	11	$	1,795
Securities Investments - Equity Securities	666		—		423		243		5,388		—		4,144		1,244
Debt Securities Carried by EGL	133,331		162		8		133,485		34,233		87		26		34,294
Investment Funds	57,093		5,460		8		62,545		22,027		5,678		6		27,699
Total	$	194,735	$	5,633	$	439	$	199,929	$	63,454	$	5,765	$	4,187	$	65,032

Investments Classified by Contractual Maturity Date

Scheduled maturities of the Company's available-for-sale debt securities within the Securities Investments portfolio as of June 30, 2018 and December 31, 2017 were as follows:

	June 30, 2018				December 31, 2017
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due within one year	$	3,090	$	3,101	$	204	$	204
Due after one year through five years	555		555		1,602		1,591
Total	$	3,645	$	3,656	$	1,806	$	1,795