Employee Benefit Plans - Defined Contribution and Profit Sharing Plans (Details) - USD ($)	12 Months Ended	24 Months Ended
Dec. 31, 2023	Dec. 31, 2023
Defined Contribution Plan Disclosure [Line Items]
Required service period to participate in plans	1 year
401(k) plan
Defined Contribution Plan Disclosure [Line Items]
Company matching contribution of employees' contributions (as a percent)		5.00%
Employer's matching contribution (in dollars)		$ 64,000
Profit sharing plan
Defined Contribution Plan Disclosure [Line Items]
Employer's matching contribution (in dollars)		$ 0

Represents the period that the employee is required to perform services from the date of employment, or anniversary thereof, in order to be eligible to participate in the defined contribution plan, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

+ Details

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Namespace Prefix:	tbnk_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480794/715-70-50-1

+ Details

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Period Type:	duration

- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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

- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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Balance Type:
Period Type: