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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.

+ Details

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- Definition

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

+ References

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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.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

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) - 2026 Convertible Notes $ / shares in Units, $ in Millions		9 Months Ended
	Mar. 05, 2021 USD ($)	Sep. 30, 2024 d $ / shares	Dec. 31, 2023 USD ($)	May 25, 2022 USD ($)
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
Fastly Conversion Option
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger		130.00%
Debt instrument, convertible, threshold trading days \| d		20
Debt instrument, convertible, threshold consecutive trading days \| d		30
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 \| d		20
Debt instrument, convertible, threshold consecutive trading days \| d		30
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 \| d		5
Debt instrument, convertible, threshold consecutive trading days \| d		10
Convertible Debt
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
Convertible Debt \| Fastly Conversion Option
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage		100.00%
Convertible Debt \| Fundamental Change
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage		100.00%