XML 46 R35.htm IDEA: XBRL DOCUMENT v3.21.2

Nature of Business (Details)	9 Months Ended
	Sep. 30, 2021 operatingMarket
Class of Stock [Line Items]
Number of operating markets	68
Common Class B
Class of Stock [Line Items]
Automatic conversion provision, percentage of Class A Common Stock	10.00%

X

- Definition

Common Stock, Automatic Conversion Provision, Percentage

+ References

No definition available.

+ Details

Name:	fsly_CommonStockAutomaticConversionProvisionPercentage
Namespace Prefix:	fsly_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Operating Markets

+ References

No definition available.

+ Details

Name:	fsly_OperatingMarkets
Namespace Prefix:	fsly_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- 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.

+ References

No definition available.

+ Details

Name:	us-gaap_ClassOfStockLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: