Regulatory Matters: Schedule of Compliance with Regulatory Capital Requirements for Mortgage Companies (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Timberland Bancorp
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage capital, Actual Amount	$ 78,480	$ 85,158
Tier 1 leverage capital, Actual Ratio	10.60%	11.50%
Tier 1 leverage capital, Capital Adequacy Purposes Amount	29,644	29,677
Tier 1 leverage capital, Capital Adequacy Purposes Ratio	4.00%	4.00%
Tier 1 risk adjusted capital, Actual Amount	78,480	85,158
Tier 1 risk adjusted capital, Actual Ratio	13.70%	15.30%
Tier 1 risk adjusted capital, Capital Adequacy Purposes Amount	22,943	22,259
Tier 1 risk adjusted capital, Capital Adequacy Purposes Ratio	4.00%	4.00%
Tier 1 risk based capital, Actual Amount	85,692	92,168
Tier 1 risk based capital, Actual Ratio	14.90%	16.60%
Total risk based capital, Capital Adequacy Purposes Amount	45,886	44,518
Total risk based capital, Capital Adequacy Purposes Ratio	8.00%	8.00%
Timberland Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage capital, Actual Amount	75,734	82,265
Tier 1 leverage capital, Actual Ratio	10.20%	11.10%
Tier 1 leverage capital, Capital Adequacy Purposes Amount	29,629	29,662
Tier 1 leverage capital, Capital Adequacy Purposes Ratio	4.00%	4.00%
Tier 1 leverage capital, To be Well Capitalized Under Prompt Corrective Action Provisions Amount	37,036	37,078
Tier 1 leverage capital, To be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00%	5.00%
Tier 1 risk adjusted capital, Actual Amount	75,734	82,265
Tier 1 risk adjusted capital, Actual Ratio	13.20%	14.80%
Tier 1 risk adjusted capital, Capital Adequacy Purposes Amount	22,939	22,255
Tier 1 risk adjusted capital, Capital Adequacy Purposes Ratio	4.00%	4.00%
Tier 1 risk adjusted capital, To be Well Capitalized Under Prompt Corrective Action Provisions Amount	34,409	33,382
Tier 1 risk adjusted capital, To be Well Capitalized Under Prompt Corrective Action Provisions Ratio	6.00%	6.00%
Tier 1 risk based capital, Actual Amount	82,945	89,273
Tier 1 risk based capital, Actual Ratio	14.50%	16.10%
Total risk based capital, Capital Adequacy Purposes Amount	45,878	44,509
Total risk based capital, Capital Adequacy Purposes Ratio	8.00%	8.00%
Total risk based capital, To be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 57,348	$ 55,636
Total risk based capital, To be Well Capitalized Under Prompt Corrective Action Provisions Ratio	10.00%	10.00%

Tier One Risk Adjusted Capital

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Tier One Risk Adjusted Capital Required For Capital Adequacy

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Tier One Risk Adjusted Capital Required For Capital Adequacy To Risk Weighted Assets

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Tier One Risk Adjusted Capital Required To Be Well Capitalized

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Tier One Risk Adjusted Capital Required To Be Well Capitalized To Risk Weighted Assets

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Tier One Risk Adjusted Capital To Risk Weighted Assets

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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-Name Accounting Standards Codification

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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