Note 18 - California First National Bancorp (Parent Only) Financial Information: (Detail) - Condensed Balance Sheets of California First National Bancorp: (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2009
ASSETS
Cash and cash equivalents	$ 56,921	$ 97,302	$ 73,988	$ 55,217
Investments and marketable securities	3,154	3,617
Other assets	1,162	1,204
	486,171	524,415	453,602
Liabilities
Accrued liabilities	2,799	3,042
	289,732	324,793
Preferred stock; 2,500,000 shares authorized; none issued	0	0
Common stock, $.01 par value; 20,000,000 shares authorized; 10,433,684 ( 2012) and 10,417,597 (2011) issued and outstanding	104	104
Additional paid in capital	3,044	2,849
Retained earnings	192,603	195,162
Other comprehensive income, net of tax	688	1,507
	196,439	199,622	198,548	191,376
	486,171	524,415
Parent Company [Member] | Investment in Banking Subsidiary [Member]
ASSETS
Investment in Subsidiaries	83,192	79,497
Parent Company [Member] | Investment in Nonbanking Subsidiaries [Member]
ASSETS
Investment in Subsidiaries	71,734	66,792
Parent Company [Member]
ASSETS
Cash and cash equivalents	6,247	6,414	7,234
Investments and marketable securities		2,322
Intercompany receivable	150	166
Intercompany note receivable	35,864	45,216
Other assets	851	1,169
Premises and other fixed assets	168	11
	198,206	201,587
Liabilities
Accrued liabilities	1,218	1,084
Intercompany payable	171	194
Income taxes payable- deferred	378	687
	1,767	1,965
Preferred stock; 2,500,000 shares authorized; none issued	0	0
Common stock, $.01 par value; 20,000,000 shares authorized; 10,433,684 ( 2012) and 10,417,597 (2011) issued and outstanding	104	104
Additional paid in capital	3,044	2,849
Retained earnings	192,603	195,162
Other comprehensive income, net of tax	688	1,507
	196,439	199,622
	$ 198,206	$ 201,587