Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) shares	Jan. 01, 2021 USD ($)	Dec. 31, 2020 USD ($)
Number Of Limited Partnerships In Housing Investments			10
Percentage of Subsidiaries Common Securities Owned by Parent Company			100.00%
Gross Loans Comprised of Commercial Mortgage Loans Percentage	49.80%
Residential Mortgages Properties Percentage	25.60%
Gross Loans Comprised of Commercial Loans Percentage	18.30%
Federal Home Loan Bank Stock	$ 17,250		$ 17,250
Federal Home Loan Bank Stock Shares (in shares) | shares	172,500
Minimum Stock Requirement on Outstanding Federal Home Loan Bank Borrowings Shares (in shares) | shares	150,000
Variable Interest Entity, Primary Beneficiary, Number of Entities	10
Goodwill, Impairment Loss	$ 0
Number of Reportable Segments	1
Retained Earnings (Accumulated Deficit), Ending Balance	$ 1,985,168		1,789,325
Loans and Leases Receivable, Allowance, Ending Balance	$ 136,157		166,538
Off-Balance Sheet, Credit Loss, Liability, Ending Balance			$ 5,880
Accounting Standards Update 2016-13 [Member]
Retained Earnings (Accumulated Deficit), Ending Balance		$ 3,100
Loans and Leases Receivable, Allowance, Ending Balance		1,600
Off-Balance Sheet, Credit Loss, Liability, Ending Balance		$ 6,000
California [Member]
Residential Mortgages Properties Percentage	48.70%