Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Note 7 - Fair Value Accounting (Details Textual) - USD ($) $ in Thousands	Jan. 01, 2029	Jan. 01, 2024	Mar. 31, 2021	Dec. 31, 2020	Apr. 01, 2019
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt Securities, Available-for-sale, Total			$ 0	$ 0
Senior Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage					1.00%
Senior Notes [Member] \| Forecast [Member]
Debt Instrument, Interest Rate, Stated Percentage	10.00%	2.00%