Note 5 - Selected Balance Sheet Accounts (Details Textual) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Capitalized Computer Software, Net, Ending Balance	$ 1.7	$ 1.4
Depreciation, Nonproduction	1.0	1.3
Amortization of Intangible Assets, Total	1.5	2.4
Cost of Sales [Member]
Depreciation, Nonproduction	0.7	0.8
Operating Expense [Member]
Depreciation, Nonproduction	$ 0.3	$ 0.5

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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The expense recognized in the current period that allocates the cost of nonproduction tangible assets over their useful lives.

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