Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2017

Marketable Securities [Abstract]

Schedule of Available-for-Sale Securities Reconciliation

The Company's marketable securities within cash equivalents and investments included in the consolidated balance sheets are detailed as follows (in thousands):

		September 30, 2017
		Amortized		Unrealized		Unrealized		Fair
		Cost		Gain		Loss		Value
U.S. Treasury securities		$	548,736	$	91	$	(817)	$	548,010
Foreign government securities			6,976		-		(6)		6,970
Corporate debt securities			1,883,688		1,474		(1,061)		1,884,101
Time deposits			403,113		-		(1)		403,112
Equity securities			77		70		-		147
	Total	$	2,842,590	$	1,635	$	(1,885)	$	2,842,340
Amounts included in:
	Cash equivalents	$	191,190	$	-	$	-	$	191,190
	Investments		2,651,400		1,635		(1,885)		2,651,150
	Total	$	2,842,590	$	1,635	$	(1,885)	$	2,842,340

		December 31, 2016
		Amortized		Unrealized		Unrealized		Fair
		Cost		Gain		Loss		Value
U.S. Treasury securities		$	570,695	$	253	$	(635)	$	570,313
Foreign government securities			17,999		-		(8)		17,991
Corporate debt securities			1,645,468		496		(2,126)		1,643,838
Time deposits			199,906		-		-		199,906
Equity securities			77		70		-		147
	Total	$	2,434,145	$	819	$	(2,769)	$	2,432,195
Amounts included in:
	Cash equivalents	$	124,793	$	1	$	-	$	124,794
	Investments		2,309,352		818		(2,769)		2,307,401
	Total	$	2,434,145	$	819	$	(2,769)	$	2,432,195

Investments Classified By Contractual Maturity Date

The estimated fair value of marketable debt securities by maturity date is as follows (in thousands):

		September 30, 2017		December 31, 2016
Due in one year or less		$	1,574,317	$	1,388,537
Due after one year through three years			864,764		843,605
	Total	$	2,439,081	$	2,232,142