The amount of advisory fees to related parties, during the period.

No definition available.

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Namespace Prefix:	tci_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Refers to due from related party payment for cost of reimbursements.

+ References

No definition available.

+ Details

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Namespace Prefix:	tci_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of intercompany property transfers.

+ References

No definition available.

+ Details

Name:	tci_IntercompanyPropertyTransfers
Namespace Prefix:	tci_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Interest income related party receivable.

+ References

No definition available.

+ Details

Name:	tci_InterestIncomeRelatedPartyReceivable
Namespace Prefix:	tci_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of net income fee to related parties during the period.

+ References

No definition available.

+ Details

Name:	tci_NetIncomeFeeToRelatedParty1
Namespace Prefix:	tci_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of notes receivable purchased from related parties.

+ References

No definition available.

+ Details

Name:	tci_NotesReceivablePurchasedRelatedParty
Namespace Prefix:	tci_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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

- Definition

outflow associated with an amount paid in advance to show an intention to complete a mortgage financing.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

+ Details

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

- Definition

Amount of cash inflow (outflow) from long-term debt by a related party. Related parties, include, but are not limited to, affiliates, owners or officers and their immediate families, and pension trusts.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24072-122690

+ Details

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

- Definition

Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

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

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_AffiliatedEntityMember
Namespace Prefix:
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Balance Type:
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Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=tci_AmericanRealtyInvestorsIncMember
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RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Due from Related Parties [RollForward]
Related party receivable, beginning balance, December 31, 2019			$ 141,541
Cash transfers			887
Advisory fees	$ (2,051)	$ (2,158)	(4,146)	$ (3,806)
Net income fee	(112)	$ (90)	(198)	$ (190)
Cost reimbursements			(1,749)
Interest income			3,235
Notes receivable purchased			(7,368)
Expenses (paid)/received by advisor			(4,511)
Financing (mortgage payments)			(166)
Intercompany property transfers			(159)
Related party receivable, ending balance, June 30, 2020	128,617		128,617
Pillar Income Asset Management, Inc [Member]
Due from Related Parties [RollForward]
Cash transfers			887
Advisory fees			(2,895)
Net income fee			(198)
Cost reimbursements			(1,749)
Notes receivable purchased			(7,368)
Expenses (paid)/received by advisor			(4,511)
Financing (mortgage payments)			(166)
Intercompany property transfers			(159)
Related party receivable, ending balance, June 30, 2020	(16,159)		(16,159)
American Realty Investors, Inc [Member]
Due from Related Parties [RollForward]
Related party receivable, beginning balance, December 31, 2019			141,541
Interest income			3,235
Related party receivable, ending balance, June 30, 2020	$ 144,776		$ 144,776