XML 60 R49.htm IDEA: XBRL DOCUMENT
v3.20.2

Leases - Additional Information (Detail) - USD ($) | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Lessee Lease Description [Line Items] |  |  |
Lessee, operating lease, lease not yet commenced, undiscounted lease payments |  |  | $ 13,900,000
Lessee, operating lease, lease not yet commenced, term of contract |  |  | 10 years
Office Space [Member] | Scenario, Forecast [Member] | Minimum [Member] |  |  |
Lessee Lease Description [Line Items] |  |  |
Lease incentive receivable |  | $ 0 |
Office Space [Member] | Scenario, Forecast [Member] | Maximum [Member] |  |  |
Lessee Lease Description [Line Items] |  |  |
Lease incentive receivable |  | $ 3,500,000 |
Topic 842 [Member] | SiriusDecisions, Inc [Member] | Facility Lease [Member] |  |  |
Lessee Lease Description [Line Items] |  |  |
Operating lease right-of-use asset impairments | $ 1,400,000 |  |

X
- Definition Lessee, operating lease, lease not yet commenced, undiscounted lease payments. + References No definition available. + Details
Name: | forr_LesseeOperatingLeaseLeaseNotYetCommencedUndiscountedLeasePayments
Namespace Prefix: | forr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition This item represents a receivable for an incentive or inducement contractually stipulated between parties to a lease whereby the lessor has committed to provide the entity (lessee) with a cash payment as inducement to enter the lease. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e40019-112707 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e40010-112707 + Details
Name: | us-gaap_LeaseIncentiveReceivable
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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_LesseeLeaseDescriptionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980 + Details
Name: | us-gaap_LesseeOperatingLeaseLeaseNotYetCommencedTermOfContract1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of loss from impairment of right-of-use asset from operating lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 25 -Paragraph 6 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=77888369&loc=SL77918431-209957 + Details
Name: | us-gaap_OperatingLeaseImpairmentLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=forr_OfficeSpaceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementScenarioAxis=srt_ScenarioForecastMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201602Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=forr_SiriusDecisionsIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=forr_FacilityLeaseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |