Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2019

Assets And Liabilities Measured At Fair Value On A Recurring Basis

Assets and Liabilities Measured at Fair Value on a Recurring Basis



	As of September 30, 2019		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
	(In thousands)
Assets:
Cash and cash equivalents:
Cash	$	402,579	$	402,579	$	—	$	—
Money market funds	74,863		74,863		—		—
Corporate securities	16,392				16,392
Available-for-sale securities:
Agency securities	1,679		—		1,679		—
Corporate securities	60,885		—		59,885		1,000
Government securities	14,182		—		14,182		—
Prepaid expenses and other current assets:
Foreign currency derivatives	542		—		542		—
Total assets	$	571,122	$	477,442	$	92,680	$	1,000
Accrued expenses and other current liabilities:
Foreign currency derivatives	2,320		—		2,320		—
Total liabilities	$	2,320	$	—	$	2,320	$	—



	As of December 31, 2018		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
	(In thousands)
Assets:
Cash and cash equivalents:
Cash	$	505,363	$	505,363	$	—	$	—
Money market funds	88,126		88,126		—		—
Agency securities	3,296		—		3,296		—
Corporate securities	9,371		—		9,371		—
Government securities	12,610		—		12,610		—
Available-for-sale securities:
Agency securities	312,948		—		312,948		—
Corporate securities	608,658		—		607,945		713
Municipal securities	2,504		—		2,504		—
Government securities	233,824		—		233,824		—
Prepaid expenses and other current assets:
Foreign currency derivatives	764		—		764		—
Total assets	$	1,777,464	$	593,489	$	1,183,262	$	713
Accrued expenses and other current liabilities:
Foreign currency derivatives	2,543		—		2,543		—
Total liabilities	$	2,543	$	—	$	2,543	$	—

Fair Value, by Balance Sheet Grouping

As of September 30, 2019, the fair value of the $750.0 million of unsecured senior notes due December 1, 2027 (the “2027 Notes"), which was determined based on inputs that are observable in the market (Level 2) based on the closing trading price per $100 as of the last day of trading for the quarter ended September 30, 2019, and carrying value of the 2027 Notes was as follows (in thousands):



	Fair Value		Carrying Value
2027 Notes	$	811,485	$	742,704