Name:	trst_CollateralDependentImpairedFinancingReceivableRecordedInvestment
Namespace Prefix:	trst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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
Namespace Prefix:	trst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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
Balance Type:	debit
Period Type:	duration

No definition available.

Name:	trst_GrossChargeOffsResidentialImpairedLoans
Namespace Prefix:	trst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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 Home Equity Lines of Credits which are classified as impaired at the end of the period.

No definition available.

Name:	trst_HomeEquityLinesOfCreditFairValueDisclosure
Namespace Prefix:	trst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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

No definition available.

Name:	trst_OtherRealEstateOwnedCommercialRealEstateFairValueDisclosure
Namespace Prefix:	trst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

No definition available.

Name:	trst_OtherRealEstateOwnedFairValueDisclosure
Namespace Prefix:	trst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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
Balance Type:	debit
Period Type:	instant

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 as first mortgages that are classified as impaired at the end of the period.

No definition available.

Name:	trst_RealEstateMortgagesOneToFourFamilyFirstMortgageClassifiedAsImpairedFairValueDisclosure
Namespace Prefix:	trst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Represents charge offs / write downs on real estate assets taken in settlement of troubled loans through surrender or foreclosure.

No definition available.

Name:	trst_RealEstateOtherValuationAdjustments
Namespace Prefix:	trst_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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=49124121&loc=SL6953550-111524

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

- References

No definition available.

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

- References

No definition available.

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

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
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