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, 2021, and 2020 (in millions):


											Reported as:
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Allowance for Credit Loss		Fair Value		Cash and Cash Equivalents		Short-term Investments		Long-term Investments
December 31, 2021
Cash	$	572.3	$	—	$	—	$	—	$	572.3	$	572.3	$	—	$	—
Level 1:
Money market funds	696.6		—		—		—		696.6		696.6		—		—
U.S. treasuries	3,429.1		6.3		(15.4)		—		3,420.0		17.0		1,100.3		2,302.7
Subtotal	4,125.7		6.3		(15.4)		—		4,116.6		713.6		1,100.3		2,302.7
Level 2:
Commercial paper	717.7		—		—		—		717.7		—		717.7		—
Corporate securities	2,485.6		2.7		(11.9)		—		2,476.4		5.0		886.7		1,584.7
U.S. government agencies	526.1		0.2		(2.9)		—		523.4		—		137.8		385.6

Municipal securities	213.4		0.7		(1.0)		—		213.1		—		70.6		142.5
Subtotal	3,942.8		3.6		(15.8)		—		3,930.6		5.0		1,812.8		2,112.8



Total assets measured at fair value	$	8,640.8	$	9.9	$	(31.2)	$	—	$	8,619.5	$	1,290.9	$	2,913.1	$	4,415.5


											Reported as:
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Allowance for Credit Loss		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

The following table summarizes the contractual maturities of the Company’s cash equivalents and available-for-sale investments (excluding cash and money market funds) as of December 31, 2021 (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 were not material and $8.3 million for the years ended December 31, 2021 and 2020, respectively. Gross realized losses recognized on the sale of investments were not material for the periods presented.

As of December 31, 2021, and 2020, net unrealized gains/(losses) on investments, net of tax, of $16.0 million and $29.5 million, 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, 2021	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Commercial paper	$	4.0	$	—	$	—	$	—	$	4.0	$	—
Corporate securities	1,687.9		(11.9)		—		—		1,687.9		(11.9)
U.S. treasuries	2,596.3		(15.4)		—		—		2,596.3		(15.4)
U.S. government agencies	412.5		(2.9)		—		—		412.5		(2.9)
Municipal securities	156.0		(1.0)		—		—		156.0		(1.0)
Total	$	4,856.7	$	(31.2)	$	—	$	—	$	4,856.7	$	(31.2)

December 31, 2020
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)

The unrealized losses on the available-for-sale investments are related to commercial paper, corporate securities, U.S. treasuries, U.S. government agencies, and municipal securities. 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.


							Reported as:
	December 31, 2020 Carrying Value		Changes in Fair Value (1)	Sales/Purchases/Others (2)	December 31, 2021 Carrying Value		Prepaids and other current assets		Intangible and other assets, net
Equity investments with readily determinable value (Level 1)	$	60.1	(17.7)	(15.5)	$	26.9	$	26.9	$	—
Equity investments without readily determinable value (Level 2)	$	30.2	43.8	(58.4)	$	15.6	$	—	$	15.6

(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 $43.8 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 are held at cost, because they lack readily determinable market values (Level 2). A total of $34.2 million of this increase in fair value was related to an equity investment in preferred shares of Broncus Holding Corporation (“Broncus”). There were no decreases in fair value reflected in net income due to impairments.

In September 2021, Broncus completed an IPO of common shares on the Stock Exchange of Hong Kong. Upon completion of its IPO, the Company’s preferred shares were converted to common shares, which have a readily determinable value (Level 1). The Company is restricted from selling these shares for a period of six months. Subsequent to the IPO, the Company recognized a $29.1 million decrease in fair value from this investment. Accordingly, for the year ended December 31, 2021, the Company has recognized a net gain of $5.1 million related to its Broncus investment, comprised of the $34.2 million gain reflected in changes in fair value for Level 2 equity investments, offset by the $29.1 million loss reflected in changes in fair value for Level 1 equity investments, both of which were reflected in Interest and other income, net.

The Company held an equity investment in common shares of Bolder Surgical Holdings, Inc. (“Bolder”), which was reflected in its financial statements on a cost basis. During the fourth quarter of 2021, Hologic, Inc., a publicly traded company, completed its acquisition of Bolder. Under the terms of the acquisition agreement, the Company received cash on the date of closing and recognized a gain on its investment of $9.5 million.

In January 2021, the Company sold all of its shares of Teladoc Health, Inc. (“Teladoc”), a publicly traded company, for $71.5 million and recognized a gain of $11.4 million, which was reflected in Interest and other income, net. This gain was offset by a $7.5 million loss recognized upon the settlement of a corresponding derivative collar contract.

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 hedged 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,
	2021		2020		2019
Recognized gains (losses) in interest and other income, net	$	15.5	$	(12.3)	$	6.4
Foreign exchange gains (losses) related to balance sheet re-measurement	$	(16.4)	$	10.9	$	(1.5)

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, 2021		December 31, 2020		December 31, 2021		December 31, 2020
Notional amounts:
Forward contracts	$	181.2	$	154.3	$	318.8	$	309.8
Gross fair value recorded in:
Prepaid and other current assets	$	5.7	$	0.9	$	6.9	$	0.7
Other accrued liabilities	$	0.5	$	4.3	$	0.8	$	5.4