XML 58 R45.htm IDEA: XBRL DOCUMENT
v3.22.0.1

The Company and Summary of Significant Accounting Policies , Cash, Cash Equivalents and Available-for-sale Investments (Details) | 12 Months Ended
--- | ---
Dec. 31, 2021
Accounting Policies [Abstract] |
Short-term investments, minimum original maturity | 3 months
Short-term investments, maximum original maturity | 1 year
Long-term investments, minimum original maturity | 1 year

X
- Definition Investments, Classification as Long-term, Minimum Maturity + References No definition available. + Details
Name: | ftnt_InvestmentsClassificationAsLongTermMinimumMaturity
Namespace Prefix: | ftnt_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Investments, Classification as Short-term, Maximum Original Maturity + References No definition available. + Details
Name: | ftnt_InvestmentsClassificationAsShortTermMaximumOriginalMaturity
Namespace Prefix: | ftnt_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Investments, Classification as Short-term, Minimum Original Maturity + References No definition available. + Details
Name: | ftnt_InvestmentsClassificationAsShortTermMinimumOriginalMaturity
Namespace Prefix: | ftnt_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_AccountingPoliciesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration