Assets Held-For-Sale, Not Part Of Disposal Group, Finite-Lived Intangible Assets, Gross

No definition available.

Name:	tree_AssetsHeldForSaleNotPartOfDisposalGroupFiniteLivedIntangibleAssetsGross
Namespace Prefix:	tree_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Assets Held-For-Sale, Not Part Of Disposal Group, Finite-Lived Intangible Assets, Net

+ References

No definition available.

+ Details

Name:	tree_AssetsHeldForSaleNotPartOfDisposalGroupFiniteLivedIntangibleAssetsNet
Namespace Prefix:	tree_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Assets Held-For-Sale, Not Part Of Disposal Group, Property, Plant, And Equipment, Accumulated Depreciation, Depletion And Amortization

+ References

No definition available.

+ Details

Name:	tree_AssetsHeldForSaleNotPartOfDisposalGroupPropertyPlantAndEquipmentAccumulatedDepreciationDepletionAndAmortization
Namespace Prefix:	tree_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Assets Held-For-Sale, Not Part Of Disposal Group, Property, Plant, And Equipment, Gross

+ References

No definition available.

+ Details

Name:	tree_AssetsHeldForSaleNotPartOfDisposalGroupPropertyPlantAndEquipmentGross
Namespace Prefix:	tree_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Assets Held-For-Sale, Not Part Of Disposal Group, Property, Plant, And Equipment, Net

+ References

No definition available.

+ Details

Name:	tree_AssetsHeldForSaleNotPartOfDisposalGroupPropertyPlantAndEquipmentNet
Namespace Prefix:	tree_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Disposal Group, Including Discontinued Operation, Closing Fee

+ References

No definition available.

+ Details

Name:	tree_DisposalGroupIncludingDiscontinuedOperationClosingFee
Namespace Prefix:	tree_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number Of Office Buildings Acquired

+ References

No definition available.

+ Details

Name:	tree_NumberOfOfficeBuildingsAcquired
Namespace Prefix:	tree_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10(c)(7)(ii))
-URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10(c)(3)(ii)(A))
-URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862

+ Details

Name:	us-gaap_AcquisitionCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 15
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=77912953&loc=d3e400-110220

+ Details

Name:	us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=116868840&loc=d3e2207-128464

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472

+ Details

Name:	us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109222160&loc=d3e957-107759

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109222650&loc=d3e1361-107760

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 3B
-URI http://asc.fasb.org/extlink&oid=109222160&loc=SL51721525-107759

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5C
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721675-107760

+ Details

Name:	us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_LandMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingAndBuildingImprovementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_LandImprovementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=tree_ComputerEquipmentandCapitalizedSoftwareMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_FurnitureAndFixturesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_LeasesAcquiredInPlaceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=tree_TwoOfficeBuildingsInCharlotteNCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DisposalGroupClassificationAxis=us-gaap_DiscontinuedOperationsDisposedOfBySaleMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=tree_TwoOfficeBuildingsInCharlotteNCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

ASSETS HELD FOR SALE ASSETS HELD FOR SALE - Schedule for assets held for sale (Details) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	Dec. 31, 2016 USD ($) building	Jun. 30, 2019 USD ($)	Sep. 30, 2019 USD ($) segment	Dec. 31, 2018 USD ($)
Long Lived Assets Held-for-sale [Line Items]
Sale price		$ 24,400
Assets held for sale			$ 0	$ 21,328
Assets Held-For-Sale, Not Part Of Disposal Group, Property, Plant, And Equipment, Gross				22,063
Assets Held-For-Sale, Not Part Of Disposal Group, Property, Plant, And Equipment, Accumulated Depreciation, Depletion And Amortization				(1,278)
Assets Held-For-Sale, Not Part Of Disposal Group, Property, Plant, And Equipment, Net				20,785
Assets Held-For-Sale, Not Part Of Disposal Group, Finite-Lived Intangible Assets, Gross				961
Accumulated Amortization			$ (79,808)	(38,941)
Assets Held-For-Sale, Not Part Of Disposal Group, Finite-Lived Intangible Assets, Net				493
Number of reportable segments \| segment			1
Land
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale				5,818
Building
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale				14,984
Site improvements
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale				950
Computer equipment and capitalized software
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale				166
Furniture and other equipment
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale				145
Tenant leases
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale				961
Accumulated Amortization				$ (468)
Two Office Buildings In Charlotte, NC [Member]
Long Lived Assets Held-for-sale [Line Items]
Number Of Office Buildings Acquired \| building	2
Fixed assets	$ 23,500
Acquisition Costs, Period Cost	$ 100
Discontinued Operations, Disposed of by Sale \| Two Office Buildings In Charlotte, NC [Member]
Long Lived Assets Held-for-sale [Line Items]
Disposal Group, Including Discontinued Operation, Closing Fee		300
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax		$ 2,700