The following tables summarize the Company’s cash and available-for-sale marketable securities’ amortized cost, gross unrealized gains, gross unrealized losses, and fair value by significant investment category reported as cash and cash equivalents or short-term or long-term investments as of December 31, 2020, and 2019 (in millions):


									Reported as:
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Cash and Cash Equivalents		Short-term Investments		Long-term Investments
December 31, 2020
Cash	$	644.3	$	—	$	—	$	644.3	$	644.3	$	—	$	—
Level 1:
Money market funds	625.8		—		—		625.8		625.8		—		—
U.S. treasuries	2,626.8		23.0		—		2,649.8		212.5		1,567.9		869.4
Subtotal	3,252.6		23.0		—		3,275.6		838.3		1,567.9		869.4
Level 2:
Commercial paper	671.3		—		—		671.3		64.1		607.2		—
Corporate securities	1,425.4		11.9		(0.2)		1,437.1		3.4		1,036.5		397.2
U.S. government agencies	716.5		2.5		—		719.0		72.5		233.6		412.9

Municipal securities	119.8		2.0		—		121.8		—		43.6		78.2
Subtotal	2,933.0		16.4		(0.2)		2,949.2		140.0		1,920.9		888.3



Total assets measured at fair value	$	6,829.9	$	39.4	$	(0.2)	$	6,869.1	$	1,622.6	$	3,488.8	$	1,757.7


									Reported as:
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Cash and Cash Equivalents		Short-term Investments		Long-term Investments
December 31, 2019
Cash	$	413.1	$	—	$	—	$	413.1	$	413.1	$	—	$	—
Level 1:
Money market funds	726.8		—		—		726.8		726.8		—		—
U.S. treasuries	1,935.8		9.7		(0.4)		1,945.1		—		890.8		1,054.3
Subtotal	2,662.6		9.7		(0.4)		2,671.9		726.8		890.8		1,054.3
Level 2:
Commercial paper	165.1		—		—		165.1		25.5		139.6		—
Corporate securities	2,096.1		16.8		(0.2)		2,112.7		—		798.5		1,314.2
U.S. government agencies	418.3		1.1		(0.2)		419.2		—		209.6		209.6
Non-U.S. government securities	4.5		—		—		4.5		—		4.5		—
Municipal securities	58.4		0.3		—		58.7		2.2		11.1		45.4
Subtotal	2,742.4		18.2		(0.4)		2,760.2		27.7		1,163.3		1,569.2



Total assets measured at fair value	$	5,818.1	$	27.9	$	(0.8)	$	5,845.2	$	1,167.6	$	2,054.1	$	2,623.5

The following table summarizes the contractual maturities of the Company’s cash equivalents and available-for-sale investments (excluding cash and money market funds) at December 31, 2020 (in millions):

Actual maturities may differ from contractual maturities, because certain borrowers have the right to call or prepay certain obligations. Gross realized gains recognized on the sale of investments was $8.3 million for the year ended December 31, 2020, and not material for the prior year comparative period. Gross realized losses recognized on the sale of investments were not material for the periods presented.

As of December 31, 2020, and 2019, net unrealized gains/(losses) on investments of $29.5 million and $20.4 million, net of tax, respectively, were included in accumulated other comprehensive income/(loss) in the accompanying Consolidated Balance Sheets.


	Unrealized losses less than 12 months				Unrealized losses 12 months or greater				Total
December 31, 2020	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Corporate securities	$	352.7	$	(0.2)	$	—	$	—	$	352.7	$	(0.2)
U.S. treasuries	278.1		—		—		—		278.1		—
U.S. government agencies	63.5		—		—		—		63.5		—
Municipal securities	21.3		—		—		—		21.3		—
Total	$	715.6	$	(0.2)	$	—	$	—	$	715.6	$	(0.2)

December 31, 2019
Corporate securities	$	237.0	$	(0.2)	$	—	$	—	$	237.0	$	(0.2)
U.S. treasuries	236.5		(0.2)		87.5		(0.2)		324.0		(0.4)
U.S. government agencies	45.9		(0.1)		45.5		(0.1)		91.4		(0.2)

Total	$	519.4	$	(0.5)	$	133.0	$	(0.3)	$	652.4	$	(0.8)

The unrealized losses on the available-for-sale investments are related to corporate securities, U.S. treasuries, and U.S. government agencies. The Company determined these unrealized losses to be temporary. Factors considered in determining whether a loss is temporary included the length of time and extent to which the investment’s fair value has been less than the cost basis, the financial condition and near-term prospects of the investee, the extent of the loss related to credit of the issuer, the expected cash flows from the security, the Company’s intent to sell the security, and whether or not the Company will be required to sell the security before the recovery of its amortized cost.

The Company holds equity investments with readily determinable fair values and equity investments without readily determinable fair values. The Company generally recognizes equity investments that do not have readily determinable fair values at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer.


									Reported as:
	December 31, 2019 Carrying Value		Changes in Fair Value (1)		Sales/Purchases/Others (2)		December 31, 2020 Carrying Value		Prepaids and other current assets		Intangible and other assets, net
Equity investments with readily determinable value (Level 1)	$	—	$	0.3	$	59.8	$	60.1	$	60.1	$	—
Equity investments without readily determinable value (Level 2)	$	24.6	$	66.2	$	(60.6)	$	30.2	$	—	$	30.2

(1) Recorded in Interest and other income, net.
(2) Other includes conversion of certain equity investments without readily determinable value to equity investments with readily determinable value.

The Company recognized a $66.2 million increase in fair value, which was reflected in Interest and other income, net, due to changes in observable prices for certain equity investments that had been held at cost, because they lacked readily determinable market values. A total of $44.8 million of this increase in fair value was related to an equity investment in preferred shares of InTouch Technologies, Inc. ("InTouch"), an entity that was acquired by Teladoc Health, Inc. ("Teladoc"), a publicly traded company, on July 1, 2020. Upon acquisition, the Company's shares were converted to shares in Teladoc, which have a readily determinable value. The Company was restricted from selling these shares for a period of six months. There were no decreases in fair value reflected in net income due to impairments.

The objective of the Company’s hedging program is to mitigate the impact of changes in currency exchange rates on net cash flow from foreign currency-denominated sales, expenses, and intercompany balances and other monetary assets or liabilities denominated in currencies other than the U.S. dollar (“USD”). The derivative assets and liabilities are measured using Level 2 fair value inputs.

Cash Flow Hedges. The Company enters into currency forward contracts as cash flow hedges to hedge certain forecasted revenue transactions denominated in currencies other than the USD, primarily the Euro (“EUR”), the British Pound (“GBP”), the Japanese Yen (“JPY”), and the Korean Won (“KRW”). The Company also enters into currency forward contracts as cash flow hedges to hedge certain forecasted expense transactions denominated in EUR and Swiss Franc (“CHF”).

For these derivatives, the Company reports the unrealized after-tax gain or loss from the hedge as a component of accumulated other comprehensive income/(loss) in stockholders’ equity and reclassifies the amount into earnings in the same period in which the hedge transaction affects earnings. The amounts reclassified to revenue and expenses related to the hedged transactions and the ineffective portions of cash flow hedges were not material for the periods presented.

Other Derivatives Not Designated as Hedging Instruments. Other derivatives not designated as hedging instruments consist primarily of forward contracts that the Company uses to hedge intercompany balances and other monetary assets or liabilities denominated in currencies other than the USD, primarily the EUR, GBP, JPY, KRW, CHF, Indian Rupee ("INR"), Mexican Peso ("MXN"), Chinese Yuan ("CNY"), and New Taiwan Dollar ("TWD").


	Years Ended December 31,
	2020		2019		2018
Recognized gains (losses) in interest and other income, net	$	(12.3)	$	6.4	$	8.7
Foreign exchange gains (losses) related to balance sheet re-measurement	$	10.9	$	(1.5)	$	(2.6)

The notional amounts for derivative instruments provide one measure of the transaction volume. Total gross notional amounts (in USD) for derivatives and the aggregate gross fair value outstanding at the end of each period were as follows (in millions):


	Derivatives Designated as Hedging Instruments				Derivatives Not Designated as Hedging Instruments
	December 31, 2020		December 31, 2019		December 31, 2020		December 31, 2019
Notional amounts:
Forward contracts	$	154.3	$	154.5	$	309.8	$	227.2
Gross fair value recorded in:
Prepaid and other current assets	$	0.9	$	1.3	$	0.7	$	2.2
Other accrued liabilities	$	4.3	$	0.5	$	5.4	$	0.7