Debt Instrument, Face Amount, Additional Principal Issuable

No definition available.

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- Definition

Debt Instrument, Repurchase, Transaction Costs

+ References

No definition available.

+ Details

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

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- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

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- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

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No definition available.

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

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- Definition

Amount, after accumulated amortization, of debt premium.

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Gross amount of debt extinguished.

+ References

No definition available.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Debt Instruments - Convertible Senior Notes (Narrative) (Details) $ / shares in Units, $ in Millions		3 Months Ended	12 Months Ended
	Mar. 05, 2021 USD ($)	Mar. 31, 2025 USD ($) day $ / shares	Dec. 31, 2024 USD ($)	Dec. 31, 2022 USD ($)	Dec. 05, 2024 USD ($)	Dec. 31, 2023 USD ($)	May 25, 2022 USD ($)
2026 Convertible Notes
Debt Instrument [Line Items]
Issuance of convertible note, net of issuance costs	$ 930.0
Debt instrument, convertible, conversion ratio		0.0097272
Debt instrument, convertible, conversion price (in US dollar per share) \| $ / shares		$ 102.80
2026 Convertible Notes \| Fastly Conversion Option
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger		130.00%
Debt instrument, convertible, threshold trading days \| day		20
Debt instrument, convertible, threshold consecutive trading days \| day		30
2026 Convertible Notes \| Holder Conversion Option One
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger		130.00%
Debt instrument, convertible, threshold trading days \| day		20
Debt instrument, convertible, threshold consecutive trading days \| day		30
2026 Convertible Notes \| Holder Conversion Option Two
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger		98.00%
Debt instrument, convertible, threshold trading days \| day		5
2028 Convertible Notes
Debt Instrument [Line Items]
Debt instrument, convertible, conversion ratio		0.0506580
Debt instrument, convertible, conversion price (in US dollar per share) \| $ / shares		$ 19.74
2028 Convertible Notes \| Fastly Conversion Option
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger		130.00%
Debt instrument, convertible, threshold trading days \| day		20
Debt instrument, convertible, threshold consecutive trading days \| day		30
2028 Convertible Notes \| Holder Conversion Option One
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger		98.00%
Debt instrument, convertible, threshold trading days \| day		5
Debt instrument, convertible, threshold consecutive trading days \| day		10
2028 Convertible Notes \| Holder Conversion Option Two
Debt Instrument [Line Items]
Debt instrument, convertible, threshold consecutive trading days \| day		10
Convertible Debt \| 2026 Convertible Notes
Debt Instrument [Line Items]
Debt instrument, face amount	$ 948.8
Interest rate, stated percentage	0.00%
Debt instrument, face amount, additional principal issuable	$ 123.8
Discount and transaction costs	$ 18.6
Debt instrument, repurchased face amount						$ 367.3	$ 235.0
Debt instrument, repurchase amount						309.1	176.4
Debt repurchase transaction costs						$ 2.0	$ 0.7
Debt extinguishment in net gain			$ 1.4	$ 54.4
Negotiated transactions of 2026 notes			157.9
Convertible Debt \| 2026 Convertible Notes \| Fastly Conversion Option
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage		100.00%
Convertible Debt \| 2026 Convertible Notes \| Fundamental Change
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage		100.00%
Convertible Debt \| 2028 Convertible Notes
Debt Instrument [Line Items]
Debt instrument, face amount		$ 150.0	$ 150.0
Interest rate, stated percentage		7.75%	7.75%
Debt instrument fair value disclosure					$ 155.7
Debt instrument unamortized premium					$ 5.7
Transaction costs		$ 5.8
Convertible Debt \| 2028 Convertible Notes \| Holder Conversion Option Two
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage		100.00%