Note 18 - California First National Bancorp (Parent Only) Financial Information: (Detail) - Condensed Statements of Earnings of California First National Bancorp: (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jun. 30, 2012	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2010
Income:
Gain (loss) on investment securities		$ 56		$ 2,342		$ 3,436
Salaries & benefits		9,037		8,602		8,198
Occupancy		936		946		932
Professional services		578		518		510
Income tax expense	5,372	5,372	6,028	6,028	6,893	6,893
Net Income	8,903	8,903	10,907	10,907	11,127	11,127
Management fee income bank subsidiary [Member] | Parent Company [Member]
Income:
Management fee income		123		174
Management fee income non-bank subsidiaries [Member] | Parent Company [Member]
Income:
Management fee income		676		795
Parent Company [Member]
Income:
Interest income non-bank subsidiary		648		774
Other interest income		78		267
Gain (loss) on investment securities				55
		1,525		2,065
Salaries & benefits		1,202		1,182
Occupancy		152		94
Professional services		243		225
Other general & administrative		187		204
		1,784		1,705
Income (Loss) before taxes and equity in undistributed earnings of subsidiaries		(259)		360
Income tax expense		262		263
Equity in undistributed earnings of subsidiaries		9,424		10,810
Net Income		$ 8,903		$ 10,907