Marketable Securities and Certificates of Deposit (Tables)

12 Months Ended

Dec. 31, 2017

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 December 31, 2017 and 2016 were as follows:

	December 31, 2017								December 31, 2016
	Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Securities Investments	$	7,194	$	—	$	4,155	$	3,039	$	6,470	$	—	$	3,945	$	2,525
Debt Securities Carried by EGL	34,233		87		26		34,294		38,392		77		15		38,454
Investment Funds	22,027		5,678		6		27,699		23,665		1,854		11		25,508
Total	$	63,454	$	5,765	$	4,187	$	65,032	$	68,527	$	1,931	$	3,971	$	66,487

Investments Classified by Contractual Maturity Date

Scheduled maturities of the Company's available-for-sale debt securities within the Securities Investments portfolio as of December 31, 2017 and 2016 were as follows:

	December 31, 2017				December 31, 2016
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due within one year	$	204	$	204	$	—	$	—
Due after one year through five years	1,602		1,591		1,748		1,728
Total	$	1,806	$	1,795	$	1,748	$	1,728