Fair Value Measurements

Fair value estimates are made as of a specific point in time based on methods using the market approach valuation method which uses prices and other relevant information generated by market transactions involving identical or comparable assets or liabilities or other valuation techniques. These techniques involve uncertainties and are affected by the assumptions used and the judgments made regarding risk characteristics of various financial instruments, discount rates, estimates of future cash flows, future expected loss experience and other factors.

Cash, Cash Equivalents and Investments. The fair value of the Company's investments in money market funds approximates their face value. Such instruments are included in cash equivalents. The Company’s money market funds and publicly traded equity securities are classified within Level 1 of the fair value hierarchy because they are valued using quoted prices for identical instruments in active markets. The fair value of the Company's other investments, including certificates of deposit, approximates their face value. The fair value of these investments is priced based on the quoted market price for similar instruments or nonbinding market prices that are corroborated by observable market data. Such instruments are classified within Level 2 of the fair value hierarchy. The Company determines the fair values of its Level 2 investments by using inputs such as actual trade data, benchmark yields, broker/dealer quotes, and other similar data, which are obtained from quoted market prices, custody bank, third-party pricing vendors, or other sources. The Company uses such pricing data as the primary input to make its assessments and determinations as to the ultimate valuation of its investment portfolio and has not made, during the periods presented, any material adjustments to such inputs. The Company is responsible for its condensed consolidated financial statements and underlying estimates.

The Company uses the specific identification method in computing realized gains and losses. Realized gains and losses on the investments are included within other income (expense) in the Company’s condensed consolidated statements of operations. The Company's investments in publicly traded equity securities are carried at fair value. Subsequent to the adoption of ASU 2016-01 in the three months ended March 31, 2018, unrealized gains and losses on publicly traded equity securities are reported within other income (expense) in the Company’s condensed consolidated statements of operations. Prior to the adoption of ASU 2016-01, unrealized gains and losses on publicly traded equity securities were reported in stockholders’ equity as a component of other comprehensive income or loss. Upon adoption of ASU 2016-01, the Company recorded a net cumulative effect increase of $2.1 million to retained earnings.

Derivative Assets and Liabilities. For derivatives, the Company uses forward contract and option models employing market observable inputs, such as spot currency rates and forward points with adjustments made to these values utilizing published credit default swap rates of its foreign exchange trading counterparties and other comparable companies. The Company has determined that the inputs used to value its derivatives fall within Level 2 of the fair value hierarchy, therefore the derivatives are categorized as Level 2.

During the three months ended March 31, 2018 and year ended December 31, 2017, the Company did not have any nonfinancial assets or liabilities measured at fair value on a recurring basis.

The Company's financial assets and liabilities measured at fair value on a recurring basis as of March 31, 2018 were as follows (in thousands):



	Fair Value at March 31, 2018		Fair Value Measurement Using
	Fair Value at March 31, 2018		Level 1		Level 2
Assets:
Cash	$	1,639,586	$	1,639,586	$	—
Money market and deposit accounts	384,222		384,222		—
Publicly traded equity securities	6,755		6,755		—
Certificates of deposit	32,451		—		32,451
Derivative instruments ⁽¹⁾	8,985		—		8,985
Total	$	2,071,999	$	2,030,563	$	41,436
Liabilities:
Derivative instruments ⁽¹⁾	$	39,984	$	—	$	39,984
Total	$	39,984	$	—	$	39,984


⁽¹⁾	Includes both foreign currency embedded derivatives and foreign currency forward contracts. Amounts are included within other current assets, other assets, others current liabilities and other liabilities in the Company’s accompanying condensed consolidated balance sheet.

The Company's financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2017 were as follows (in thousands):



	Fair Value at December 31, 2017		Fair Value Measurement Using
	Fair Value at December 31, 2017		Level 1		Level 2
Assets:
Cash	$	985,382	$	985,382	$	—
Money market and deposit accounts	427,135		427,135		—
Publicly traded equity securities	6,163		6,163		—
Certificates of deposit	31,351		—		31,351
Derivative instruments ⁽¹⁾	8,285		—		8,285
Total	$	1,458,316	$	1,418,680	$	39,636
Liabilities:
Derivative instruments ⁽¹⁾	$	40,847	$	—	$	40,847
Total	$	40,847	$	—	$	40,847


⁽¹⁾	Includes both foreign currency embedded derivatives and foreign currency forward contracts. Amounts are included within other current assets, other assets, other current liabilities and other liabilities in the Company's accompanying condensed consolidated balance sheet.

The Company did not have any Level 3 financial assets or financial liabilities as of March 31, 2018 and December 31, 2017.