Plan Description and Basis of Presentation - Narrative (Details) - EBP 002	12 Months Ended
Sep. 30, 2025 USD ($) yr h shares
EBP, Description of Plan [Line Items]
Employee minimum participant age \| yr	18
Employee minimum participant age, ESOP \| yr	21
Contribution requisite service period \| h	1,000
Automatic deferral rate	1.00%
Automatic deferral rate, year one	1.00%
Automatic deferral rate, year two	2.00%
Automatic deferral rate, year three	3.00%
Automatic deferral rate, year four	4.00%
Automatic deferral rate, year five	5.00%
Participant compensation matched, percentage	3.00%
Safe harbor contribution	$ 544,897
Employer contribution, amount	541,170
Involuntary cash-out amount	1,000
Involuntary IRA transfer, maximum amount	5,000
Involuntary IRA transfer, minimum amount	1,000
Minimum vested amount for optional distribution	$ 5,000
ESOP account limitation	5 years
Employer discretionary contribution maximum vesting age \| yr	65
Benefit payments	$ 2,578,053
Employer contribution, deferral, rollover and safe harbor profit sharing contributions, vesting percentage	100.00%
Discretionary employer contributions, vesting percentage	100.00%
Common Stock
EBP, Description of Plan [Line Items]
Shares distributed for quarterly dividends from ESOP component (in shares) \| shares	3,975
Nonparticipant Directed
EBP, Description of Plan [Line Items]
Benefit payments	$ 395,089
Decrease from shares allocated to ESOP	275,210
Nonparticipant Directed \| Common Stock
EBP, Description of Plan [Line Items]
Benefit payments	$ 119,879
6 or more
EBP, Description of Plan [Line Items]
Discretionary employer contributions, vesting percentage	100.00%

EBP, Change In Net Asset Available For Benefit, Decrease Shares

No definition available.

Name:	tsbk_EBPChangeInNetAssetAvailableForBenefitDecreaseShares
Namespace Prefix:	tsbk_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Contribution Annual Requisite Service Period

+ References

No definition available.

+ Details

Name:	tsbk_EBPContributionAnnualRequisiteServicePeriod
Namespace Prefix:	tsbk_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, ESOP Account Limitation

+ References

No definition available.

+ Details

Name:	tsbk_EBPESOPAccountLimitation
Namespace Prefix:	tsbk_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Employee Minimum Participant Age

+ References

No definition available.

+ Details

Name:	tsbk_EBPEmployeeMinimumParticipantAge
Namespace Prefix:	tsbk_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Employee Minimum Participant Age, ESOP

+ References

No definition available.

+ Details

Name:	tsbk_EBPEmployeeMinimumParticipantAgeESOP
Namespace Prefix:	tsbk_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Employer Contribution, 401(k)

+ References

No definition available.

+ Details

Name:	tsbk_EBPEmployerContribution401k
Namespace Prefix:	tsbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

EBP, Employer Contribution, Deferral, Rollover And Safe Harbor Profit Sharing Contributions, Vesting Percentage

+ References

No definition available.

+ Details

Name:	tsbk_EBPEmployerContributionDeferralRolloverAndSafeHarborProfitSharingContributionsVestingPercentage
Namespace Prefix:	tsbk_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Employer Contribution, Safe Harbor Contribution

+ References

No definition available.

+ Details

Name:	tsbk_EBPEmployerContributionSafeHarborContribution
Namespace Prefix:	tsbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

EBP, Employer Contribution, Safe Harbor Match, Percentage

+ References

No definition available.

+ Details

Name:	tsbk_EBPEmployerContributionSafeHarborMatchPercentage
Namespace Prefix:	tsbk_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Employer Discretionary Contribution Maximum Vesting Age

+ References

No definition available.

+ Details

Name:	tsbk_EBPEmployerDiscretionaryContributionMaximumVestingAge
Namespace Prefix:	tsbk_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Employer Discretionary Contribution Vesting Percentage

+ References

No definition available.

+ Details

Name:	tsbk_EBPEmployerDiscretionaryContributionVestingPercentage
Namespace Prefix:	tsbk_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Involuntary Cash-Out Limit

+ References

No definition available.

+ Details

Name:	tsbk_EBPInvoluntaryCashOutLimit
Namespace Prefix:	tsbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

EBP, Involuntary IRA Transfer, Maximum Amount

+ References

No definition available.

+ Details

Name:	tsbk_EBPInvoluntaryIRATransferMaximumAmount
Namespace Prefix:	tsbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

EBP, Involuntary IRA Transfer, Minimum Amount

+ References

No definition available.

+ Details

Name:	tsbk_EBPInvoluntaryIRATransferMinimumAmount
Namespace Prefix:	tsbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

EBP, Minimum Vested Amount For Optional Distribution

+ References

No definition available.

+ Details

Name:	tsbk_EBPMinimumVestedAmountForOptionalDistribution
Namespace Prefix:	tsbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

EBP, Participant Contribution, Automatic, Deferral Rate, Year Five

+ References

No definition available.

+ Details

Name:	tsbk_EBPParticipantContributionAutomaticDeferralRateYearFive
Namespace Prefix:	tsbk_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Automatic, Deferral Rate, Year Four

+ References

No definition available.

+ Details

Name:	tsbk_EBPParticipantContributionAutomaticDeferralRateYearFour
Namespace Prefix:	tsbk_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Automatic, Deferral Rate, Year One

+ References

No definition available.

+ Details

Name:	tsbk_EBPParticipantContributionAutomaticDeferralRateYearOne
Namespace Prefix:	tsbk_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Automatic, Deferral Rate, Year Three

+ References

No definition available.

+ Details

Name:	tsbk_EBPParticipantContributionAutomaticDeferralRateYearThree
Namespace Prefix:	tsbk_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Automatic, Deferral Rate, Year Two

+ References

No definition available.

+ Details

Name:	tsbk_EBPParticipantContributionAutomaticDeferralRateYearTwo
Namespace Prefix:	tsbk_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of decrease in net asset available for benefit from shares allocated for employee stock ownership plan (ESOP) or feature within employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-02)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAllocatedSharesForEsop
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of decrease in net asset available for benefit from payment of benefit to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), including, but not limited to, withdrawal.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule III))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 50
-Paragraph 2B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477783/962-325-50-2B

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 45
-Paragraph 7
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477063/962-205-45-7

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-04(5)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForPaymentToParticipant
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-SubTopic 205
-Topic 962
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanParticipantContributionAutomaticDeferralRate
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=tsbk_EBP002Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap-ebp_EmployeeBenefitPlanParticipantDirectedStatusAxis=us-gaap-ebp_EmployeeBenefitPlanNonparticipantDirectedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	tsbk_EBPEmployerDiscretionaryContributionServicePeriodAxis=tsbk_SixYearsOrMoreMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: