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v3.23.3

Debt Securities - Amortized Cost, Gross Unrealized Gains and Losses, Allowance for Credit Losses and Fair Value of Debt Securities Available-For-Sale (Details) - USD ($) $ in Millions | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost, current | $ 804.8 | $ 735.8
Unrealized gain, current | 0.0 | 0.0
Unrealized loss, current | (3.4) | (9.4)
Fair value, current | 801.4 | 726.4
Amortized cost, noncurrent | 458.6 | 304.5
Unrealized gain, noncurrent | 0.1 | 0.2
Unrealized loss, noncurrent | (4.0) | (5.3)
Fair value, noncurrent | 454.7 | 299.4
Commercial paper |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost, current | 137.4 | 156.2
Unrealized gain, current | 0.0 | 0.0
Unrealized loss, current | 0.0 | (0.2)
Fair value, current | 137.4 | 156.0
Corporate debt securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost, current | 306.6 | 296.2
Unrealized gain, current | 0.0 | 0.0
Unrealized loss, current | (1.9) | (3.2)
Fair value, current | 304.7 | 293.0
Amortized cost, noncurrent | 341.3 | 259.5
Unrealized gain, noncurrent | 0.1 | 0.2
Unrealized loss, noncurrent | (3.1) | (4.3)
Fair value, noncurrent | 338.3 | 255.4
Securities of government-sponsored entities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost, current | 360.8 | 283.4
Unrealized gain, current | 0.0 | 0.0
Unrealized loss, current | (1.5) | (6.0)
Fair value, current | 359.3 | 277.4
Amortized cost, noncurrent | 117.3 | 45.0
Unrealized gain, noncurrent | 0.0 | 0.0
Unrealized loss, noncurrent | (0.9) | (1.0)
Fair value, noncurrent | $ 116.4 | $ 44.0

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