Name:	trst_MortgageBackedSecuritiesAndCollateralizedMortgageObligationsCommercialFairValueDisclosure
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No definition available.

Name:	trst_MortgageBackedSecuritiesAndCollateralizedMortgageObligationsResidentialFairValueDisclosure
Namespace Prefix:	trst_
Data Type:	xbrli:monetaryItemType
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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Other securities, those which are not otherwise identified in the taxonomy.

No definition available.

Name:	trst_OtherSecuritiesFairValueDisclosure
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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Small business administration guaranteed participation securities.

No definition available.

Name:	trst_SmallBusinessAdministrationGuaranteedParticipationSecuritiesFairValueDisclosure
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No definition available.

Name:	trst_StateAndPoliticalSubdivisionsFairValueDisclosure
Namespace Prefix:	trst_
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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities of U.S. government-sponsored enterprises.

No definition available.

Name:	trst_USGovernmentSponsoredEnterprisesFairValueDisclosure
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Data Type:	xbrli:monetaryItemType
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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- References

No definition available.

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