Note 15 - Regulatory Capital Requirements: (Details)	Jun. 30, 2013	Jun. 30, 2012
California First National Bancorp [Member]
Note 15 - Regulatory Capital Requirements: (Details) [Line Items]
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	6.00%
Capital Required for Capital Adequacy to Risk Weighted Assets	10.00%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	5.00%
Tier One Leverage Capital to Average Assets	32.10%	40.70%
California First National Bank [Member]
Note 15 - Regulatory Capital Requirements: (Details) [Line Items]
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	4.00%
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%
Tier One Leverage Capital to Average Assets	20.40%	22.40%
California First National Bank [Member] \| Minimum [Member]
Note 15 - Regulatory Capital Requirements: (Details) [Line Items]
Tier One Leverage Capital to Average Assets	14.00%

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 505

-Section 50

-Paragraph 1H

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=7881181&loc=d3e65071-112826

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 505

-Section 50

-Paragraph 1

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7881181&loc=SL5958568-112826

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 942

-SubTopic 505

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7881181&loc=SL5958570-112826

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- Definition

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

+ References

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- Definition

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

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- Definition

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.

+ References

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