Note 8 - Short-term Borrowings - Components of Short-term Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Short-term borrowings	$ 12,940	$ 0
Maximum Month-end Outstanding Amount	12,940	0	$ 161,950
Average Outstanding Amount	1,031	97	49,165
Overnight Borrowings [Member]
Short-term borrowings	12,930	0
Maximum Month-end Outstanding Amount	12,930	0	9,159
Average Outstanding Amount	$ 1,025	$ 97	$ 4,175
Weighted Average Interest Rate	4.39%	1.06%	2.13%
Interest Rate At Year End	4.45%	0.00%	0.00%
Other Short-term Borrowings [Member]
Short-term borrowings	$ 10	$ 0
Maximum Month-end Outstanding Amount	10
Average Outstanding Amount	$ 6
Weighted Average Interest Rate	0.00%
Interest Rate At Year End	0.00%
Paycheck Protection Program Liquidity Facility [Member]
Maximum Month-end Outstanding Amount			$ 152,791
Average Outstanding Amount			$ 44,990
Weighted Average Interest Rate			0.35%
Interest Rate At Year End			0.00%

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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+ References

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