v3.26.1
Fair Value Measurements
 3 Months Ended
Mar. 31, 2026
Fair Value Disclosures [Abstract]  
Fair Value Measurements Fair Value Measurements
Assets measured at fair values on a recurring basis
    We measure and report our cash equivalents, restricted cash, and available-for-sale marketable securities at fair value on a recurring basis. We use a fair value hierarchy to measure fair value, maximizing the use of observable inputs. The three-tiers of the fair value hierarchy are as follows: Level I—Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date, Level II—Inputs are observable, unadjusted quoted prices in active markets for similar assets or liabilities, unadjusted quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the related assets or liabilities, and Level III—Inputs that are generally unobservable and typically reflect management's estimate of assumptions that market participants would use in pricing the asset or liability. We don't have any level III financial assets measured at fair value on a recurring basis. The following tables summarize the fair value of these financial assets by significant investment category and their levels within the fair value hierarchy (in millions):
March 31, 2026December 31, 2025
Level ILevel IILevel IIITotal Level ILevel IILevel IIITotal
Financial Assets:
Cash Equivalents:
Money market funds $973.2 $— $— $973.2 $1,174.8 $— $— $1,174.8 
Commercial paper— 63.7 — 63.7 — 29.8 — 29.8 
Corporate bonds— — — — — 6.6 — 6.6 
U.S. government notes48.4 — — 48.4 124.9 — — 124.9 
Agency securities— 20.0 — 20.0 — — — — 
1,021.6 83.7 — 1,105.3 1,299.7 36.4 — 1,336.1 
Marketable Securities:
Commercial paper— 311.1 — 311.1 — 83.0 — 83.0 
U.S. government notes2,728.1 — — 2,728.1 2,854.3 — — 2,854.3 
Corporate bonds— 5,059.7 — 5,059.7 — 4,329.7 — 4,329.7 
Municipal bonds— 14.5 — 14.5 — 14.5 — 14.5 
Agency securities— 1,450.3 — 1,450.3 — 1,497.6 — 1,497.6 
2,728.1 6,835.6 — 9,563.7 2,854.3 5,924.8 — 8,779.1 
Other Assets:
Money market funds - restricted cash1.4 — — 1.4 1.4 — — 1.4 
Total Financial Assets$3,751.1 $6,919.3 $— $10,670.4 $4,155.4 $5,961.2 $— $10,116.6 
    During the three months ended March 31, 2026, the Company did not make any transfers between the levels of the fair value hierarchy.
    The following table summarizes the amortized cost, unrealized gains and losses, and fair value of our debt securities measured at fair value on a recurring basis (in millions):
March 31, 2026December 31, 2025
Amortized CostUnrealized GainsUnrealized LossesFair ValueAmortized CostUnrealized GainsUnrealized LossesFair Value
Commercial paper$374.8 $— $— $374.8 $112.8 $— $— $112.8 
U.S. government2,777.5 2.8 (3.8)2,776.5 2,970.4 8.8 — 2,979.2 
Corporate bonds5,066.3 4.7 (11.3)5,059.7 4,321.2 16.0 (0.9)4,336.3 
Municipal bonds14.5 — — 14.5 14.5 — — 14.5 
Agency securities1,474.1 0.6 (4.4)1,470.3 1,495.5 2.7 (0.6)1,497.6 
Total $9,707.2 $8.1 $(19.5)$9,695.8 $8,914.4 $27.5 $(1.5)$8,940.4 
    For debt securities in unrealized loss positions, it is not likely that we will be required to sell such securities before recovery of their amortized cost basis nor do we have the intent to sell such securities before maturity. We invest in debt securities that have maximum maturities of three years that are generally deemed to be low risk based on their credit ratings from the major rating agencies. The longer the duration of these debt securities, the more susceptible they are to changes in market interest rates and bond yields. Given the relatively short-term and conservative nature of our portfolio, our debt securities are generally not subject to credit risk; therefore, we did not recognize any credit losses or non-credit-related impairments related to such securities for the three months ended March 31, 2026. All unrealized gains or losses were recognized in other comprehensive income (loss). Realized gains or losses were immaterial for the three months ended March 31, 2026.
    The following table is an analysis of our debt securities in unrealized loss positions (in millions):
March 31, 2026
Unrealized Losses within 12 months Unrealized Losses 12 months or greaterTotal
Fair ValueUnrealized LossesFair ValueUnrealized LossesFair ValueUnrealized Losses
Commercial paper$10.0 $— $— $— $10.0 $— 
U.S. government notes1,560.6 (3.8)10.0 — 1,570.6 (3.8)
Corporate bonds2,925.3 (11.3)6.0 — 2,931.3 (11.3)
Municipal bonds11.4 — — — 11.4 — 
Agency securities1,053.0 (4.4)— — 1,053.0 (4.4)
Total $5,560.3 $(19.5)$16.0 $— $5,576.3 $(19.5)
     As of March 31, 2026, we had no marketable debt securities with contractual maturities that exceeded three years. The fair values of marketable debt securities, by remaining contractual maturities, are as follows (in millions):
March 31, 2026
Fair Value
Due in 1 year or less$3,501.6 
Due in 1 to 3 years6,062.1 
Total debt securities $9,563.7 
    The weighted-average remaining duration of our marketable debt securities is approximately 1.4 years as of March 31, 2026. As we view these marketable debt securities as available to support current operations, we classify marketable debt securities with maturities beyond 12 months as current assets under the caption "Marketable securities" on the condensed consolidated balance sheets.