Name:	trst_CollateralDependentImpairedFinancingReceivableRecordedInvestment
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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 Commercial Real Estate Loans with are classified as impaired at the end of the period.

No definition available.

Name:	trst_CommercialRealEstateLoansClassifiedAsImpairedFairValueDisclosure
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Reflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, typically because they are considered to be not salvageable or have been purchased by unconsolidated collection entities.

No definition available.

Name:	trst_GrossChargeOffsCommercialImpairedLoans
Namespace Prefix:	trst_
Data Type:	xbrli:monetaryItemType
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No definition available.

Name:	trst_GrossChargeOffsResidentialImpairedLoans
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The fair value disclosure of commercial real estate included in other real estate owned.

No definition available.

Name:	trst_OtherRealEstateOwnedCommercialRealEstateFairValueDisclosure
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Data Type:	xbrli:monetaryItemType
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No definition available.

Name:	trst_OtherRealEstateOwnedFairValueDisclosure
Namespace Prefix:	trst_
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The fair value disclosure of residential real estate properties included in other real estate owned.

No definition available.

Name:	trst_OtherRealEstateOwnedResidentialRealEstatePropertiesFairValueDisclosure
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 real estate mortgages for one to four family units that are classified as impaired at the end of the period.

No definition available.

Name:	trst_RealEstateMortgagesOneToFourFamilyClassifiedAsImpairedFairValueDisclosure
Namespace Prefix:	trst_
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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Data Type:	xbrli:monetaryItemType
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Percentage of adjustment to the observed price for a similar asset or liability when an identical transaction does not exist, used as an input to measure fair value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Description of the inputs and valuation technique(s) used to measure fair value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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- References

No definition available.

Name:	us-gaap_LoanAndLeaseReceivablesImpairedAbstract
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Data Type:	xbrli:stringItemType
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- References

No definition available.

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

Amount of the valuation allowance for real estate owned that was applied in the period against the carrying amount of real estate owned that was sold, written down or written off.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Data Type:	xbrli:monetaryItemType
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