Name:	trst_ActualNetLossHistoryPeriodUsedInDeterminingHistoricalLoss
Namespace Prefix:	trst_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The age of retirees that the company provides access to medicare supplemental program.

No definition available.

Name:	trst_AgeAtWhichCompanyProvidesAccessToMedicareSupplementalProgramForRetirees
Namespace Prefix:	trst_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The age under which retirees are permitted to participate in the company's medical plan, and retirees pay all of their premiums.

No definition available.

Name:	trst_AgeUnderWhichRetireesCanParticipateInCompanySMedicalPlan
Namespace Prefix:	trst_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The amount of assets not included on the consolidated financial statements that an investment adviser manages on behalf of investors.

No definition available.

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

The loan-to-value ratio that the company's allowance methodology also includes additional allocation percentage for during the period.

No definition available.

Name:	trst_LoanToValueRatioApplicableToAdditionalAllowance
Namespace Prefix:	trst_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The past due period before for loans considered to be in payment default.

No definition available.

Name:	trst_NonpaymentPeriodOfLoansMovedToNonaccrualStatus
Namespace Prefix:	trst_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The number of past due payments on loans classified as nonperforming.

No definition available.

Name:	trst_NumberOfPastDuePaymentsForLoansClassifiedAsNonperforming
Namespace Prefix:	trst_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

The portion of the previous two years net income of the bank subsidiary that has not been paid to the parent and may be paid to the parent in the following fiscal year for dividend distributions in accordance with federal banking regulations.

No definition available.

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

- Details

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

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

No definition available.

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

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

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

No definition available.

Name:	us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule III

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 28

-Article 12

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6375948&loc=d3e4437-111522

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 2, 9, 10, 11

-IssueDate 2006-05-01

-Chapter 11

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.