Leases Schedule of Lease Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
2023	$ 1,904
2024	1,993
2025	1,424
2026	893
2027	266
Thereafter	50
Total undiscounted payments	6,530
Less: present value adjustment	$ (436)
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Lease liabilities
Operating lease, liabilities	$ 6,094
Finance Lease, Liability, to be Paid, Year One	242
Finance Lease, Liability, to be Paid, Year Two	201
Finance Lease, Liability, to be Paid, Year Three	171
Finance Lease, Liability, to be Paid, Year Four	134
Finance Lease, Liability, to be Paid, Year Five	51
Finance Lease, Liability, to be Paid, after Year Five	0
Finance Lease, Liability, Payment, Due, Total	799
Finance Lease, Liability, Undiscounted Excess Amount	$ (54)
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Lease liabilities
Finance Lease, Liability	$ 745
LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	2,146
LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	2,194
LesseeOperatingLeaseLiabilityPaymentsDueYearThree	1,595
LesseeLeaseLiabilityPaymentsDueYearFour	1,027
LesseeLeaseLiabilityPaymentsDueYearFive	317
LesseeLeaseLiabilityPaymentsDueAfterYearFive	50
LesseeLeaseLiabilityPaymentsDue	7,329
LesseeLeaseLiabilityUndiscountedExcessAmount	(490)
Lease liabilities	$ 6,839	$ 5,329

Present value of lessee's discounted obligation for lease payments from operating and financing leases.

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for operating and financing leases.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for operating and financing leases due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating and financing leases to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating and financing leases to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating and financing leases to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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Namespace Prefix:	itic_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for operating and financing leases to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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Namespace Prefix:	itic_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments for operating and financing leases to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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Namespace Prefix:	itic_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating and financing leases.

+ References

No definition available.

+ Details

Name:	itic_LesseeLeaseLiabilityUndiscountedExcessAmount
Namespace Prefix:	itic_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918701-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease.

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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

- Definition

Indicates line item in statement of financial position that includes finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918631-209977

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

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- References

No definition available.

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

+ References

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Namespace Prefix:	us-gaap_
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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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- Definition

Indicates line item in statement of financial position that includes operating lease liability.

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