Note 2 - Significant Accounting Policies and Consolidated Financial Statement Components - Components of Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Servicing income		$ 2,060	$ 1,148
Credit and Debit Card [Member]
Servicing income	[1]	928	444
Servicing Income [Member]
Servicing income		686	632
Service Charges and Other Customer Related Fees [Member]
Servicing income		446	72
Credit and Other Investments [Member]
Servicing income		1,776	871
Credit and Other Investments [Member] | Credit and Debit Card [Member]
Servicing income	[1]	928	444
Credit and Other Investments [Member] | Servicing Income [Member]
Servicing income		419	402
Credit and Other Investments [Member] | Service Charges and Other Customer Related Fees [Member]
Servicing income		429	25
Auto Finance [Member]
Servicing income		284	277
Auto Finance [Member] | Credit and Debit Card [Member]
Servicing income	[1]
Auto Finance [Member] | Servicing Income [Member]
Servicing income		267	230
Auto Finance [Member] | Service Charges and Other Customer Related Fees [Member]
Servicing income		$ 17	$ 47

[1] Interchange revenue is presented net of customer reward expense