Deferral period of all past due loans in accordance with the bankruptcy court order.

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

No definition available.

+ Details

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- Definition

Amount of investment in financing receivables (after modification) modified by troubled debt restructurings.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of investment in financing receivables (before modification) modified by troubled debt restructurings.

+ References

No definition available.

+ Details

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings which were previously performing. Classification basis is the OCC interpretation regarding borrowers in chapter 7 bankruptcy and not re-affirming their debt.

+ References

No definition available.

+ Details

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- Details

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring for loans which were previously performing and have collateral deficiency. Basis for write down is the OCC interpretation regarding borrowers in chapter 7 bankruptcy and not re-affirming their debt.

+ References

No definition available.

+ Details

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- Details

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- Definition

Number of days past due when loan considered in payment default consistent with the treatment of bankruptcy court order.

+ References

No definition available.

+ Details

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

- Definition

Number of days past due when loan is considered to be in payment default under the modified terms.

+ References

No definition available.

+ Details

Name:	trst_NumberOfDaysPastDueWhenLoansConsideredInPaymentDefaultUnderModifiedTerms
Namespace Prefix:	trst_
Data Type:	xbrli:durationItemType
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- Details

Name:	us-gaap_FinancingReceivableModificationsLineItems
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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6951948&loc=d3e18845-111554

+ Details

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

- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953682-111524

+ Details

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

+ Details

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

- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Loans and Allowance for Loan Losses, Troubled Debt Restructurings (Details) (USD $)	3 Months Ended	9 Months Ended			3 Months Ended	9 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 Commercial [Member] Commercial real estate [Member]	Sep. 30, 2012 Real estate mortgage - 1 to 4 family [Member]	Sep. 30, 2012 Real estate mortgage - 1 to 4 family [Member]	Sep. 30, 2012 New York and other states [Member]	Sep. 30, 2012 New York and other states [Member]	Sep. 30, 2012 New York and other states [Member] Commercial [Member] Commercial real estate [Member]	Sep. 30, 2012 New York and other states [Member] Commercial [Member] Commercial real estate [Member]	Sep. 30, 2012 New York and other states [Member] Commercial [Member] Other [Member]	Sep. 30, 2012 New York and other states [Member] Commercial [Member] Other [Member]	Sep. 30, 2012 New York and other states [Member] Real estate mortgage - 1 to 4 family [Member] First mortgages [Member]	Sep. 30, 2012 New York and other states [Member] Real estate mortgage - 1 to 4 family [Member] First mortgages [Member]	Sep. 30, 2012 New York and other states [Member] Real estate mortgage - 1 to 4 family [Member] Home equity loans [Member]	Sep. 30, 2012 New York and other states [Member] Real estate mortgage - 1 to 4 family [Member] Home equity loans [Member]	Sep. 30, 2012 New York and other states [Member] Real estate mortgage - 1 to 4 family [Member] Home equity lines of credit [Member]	Sep. 30, 2012 New York and other states [Member] Real estate mortgage - 1 to 4 family [Member] Home equity lines of credit [Member]	Sep. 30, 2012 Florida [Member]	Sep. 30, 2012 Florida [Member]	Sep. 30, 2012 Florida [Member] Commercial [Member] Commercial real estate [Member]	Sep. 30, 2012 Florida [Member] Commercial [Member] Commercial real estate [Member]	Sep. 30, 2012 Florida [Member] Commercial [Member] Other [Member]	Sep. 30, 2012 Florida [Member] Commercial [Member] Other [Member]	Sep. 30, 2012 Florida [Member] Real estate mortgage - 1 to 4 family [Member] First mortgages [Member]	Sep. 30, 2012 Florida [Member] Real estate mortgage - 1 to 4 family [Member] First mortgages [Member]	Sep. 30, 2012 Florida [Member] Real estate mortgage - 1 to 4 family [Member] Home equity lines of credit [Member]	Sep. 30, 2012 Florida [Member] Real estate mortgage - 1 to 4 family [Member] Home equity lines of credit [Member]
Financing Receivable, Modifications [Line Items]
TDR classifications from previously performing loans					$ 10,100,000	$ 10,100,000
TDR's amount	17,300,000	17,300,000	5,200,000	1,500,000
Chargeoffs on loans identified as TDR's	1,100,000	1,400,000
Collateral deficiency charge-offs for TDR reclassifications					804,000	804,000
Modified loans by class that were determined to be TDR's [Abstract]
Number of Contracts							116	141	2	2	0	0	73	94	14	17	27	28	10	14	0	0	0	0	8	12	2	2
Pre-Modification Outstanding Recorded Investment							10,933,000	14,197,000	166,000	166,000	0	0	8,807,000	11,845,000	485,000	605,000	1,475,000	1,581,000	928,000	1,356,000	0	0	0	0	878,000	1,306,000	50,000	50,000
Post-Modification Outstanding Recorded Investment							10,933,000	14,197,000	166,000	166,000	0	0	8,807,000	11,845,000	485,000	605,000	1,475,000	1,581,000	928,000	1,356,000	0	0	0	0	878,000	1,306,000	50,000	50,000
Financing Receivable Modifications Recorded Investment Previously Performing					10,100,000	10,100,000
Loans modified for which there was payment default [Abstract]
Number of Contracts							29	29	0	0	0	0	24	24	3	3	2	2	8	8	0	0	0	0	7	7	1	1
Recorded Investment							$ 3,274,000	$ 3,274,000	$ 0	$ 0	$ 0	$ 0	$ 3,042,000	$ 3,042,000	$ 96,000	$ 96,000	$ 136,000	$ 136,000	$ 766,000	$ 766,000	$ 0	$ 0	$ 0	$ 0	$ 719,000	$ 719,000	$ 47,000	$ 47,000
Deferral period of past due loans		60 months
Number of days past due when loans considered in payment default		90 days
Number of days past due, loan considered in payment default		30 days