Name:	tbnk_HeldToMaturitySecuritiesDebtMaturitiesNextRollingFiveYearsAmortizedCost
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Fair value of held-to-maturity debt securities maturing in the next rolling five years following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

No definition available.

Name:	tbnk_HeldToMaturitySecuritiesDebtMaturitiesNextRollingFiveYearsFairValue
Namespace Prefix:	tbnk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
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-URI https://asc.fasb.org//1943274/2147481962/310-10-50-7A

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing after tenth rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

No definition available.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in sixth through tenth rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

No definition available.

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- References

No definition available.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-5A

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 4: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
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Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing after rolling tenth fiscal year following current statement of financial position date. For interim and annual periods when interim period is reported on rolling approach.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)(4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-5

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 320
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480832/942-320-50-3

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Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing in sixth through tenth rolling fiscal year following current statement of financial position date. For interim and annual periods when interim period is reported on rolling approach.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-5

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 320
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480832/942-320-50-3

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

- References

No definition available.