Note 10 - Redeemable, Convertible Preferred Stock (Details Textual)						1 Months Ended	9 Months Ended	12 Months Ended
	Feb. 26, 2024	Feb. 26, 2023	Mar. 30, 2021 USD ($) shares	Feb. 26, 2021 USD ($) $ / shares shares	Nov. 15, 2016 USD ($) $ / shares shares	Jul. 31, 2020 USD ($)	Sep. 30, 2022 USD ($) $ / shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) $ / shares	Dec. 31, 2020 USD ($)	Feb. 25, 2021 $ / shares
Preferred Stock, No Par Value (in dollars per share) | $ / shares								$ 0
Embedded Derivative, Fair Value of Embedded Derivative Liability								$ 4,000,000	$ 7,000,000
Series A Preferred Stock [Member]
Preferred Stock, Dividend Rate, Percentage					5.50%
Temporary Equity, Liquidation Preference Per Share (in dollars per share) | $ / shares								$ 100	$ 100
Proceeds from Issuance of Preferred Stock and Preference Stock					$ 198,000,000
Preferred Stock, Redemption Price Per Share (in dollars per share) | $ / shares					$ 100
Stock Repurchased During Period, Shares (in shares) | shares				1,000,000
Payments for Repurchase of Preferred Stock and Preference Stock								$ (0)	$ 100,000,000	$ (0)
Common Stock Price Equal Or Exceeds Preferred Stock Conversion Price Percentage					125.00%
Net Proceeds Received Allocated To Derivative Liability					$ 43,000,000
Temporary Equity Issuance Of Redeemable Convertible Preferred Stock Net Of Offering Costs And Derivative Liability					155,000,000
Gross Proceeds From Issuance Of Preferred Stock And Preference Stock					200,000,000
Derivative Liability, Subject to Master Netting Arrangement, before Offset					43,000,000
Transaction Costs					$ 2,000,000
Temporary Equity Preferred Stock Prior To Extinguishment Carrying Value				$ 203,000,000
Temporary Equity Deemed Preferred Stock Dividends				$ 8,000,000
Dividends, Total						$ 11,000,000
Series A Preferred Stock [Member] | Purchase Agreement [Member]
Temporary Equity, Shares Issued (in shares) | shares					2,000,000
Preferred Stock, Dividend Rate, Percentage					5.50%
Temporary Equity, Liquidation Preference					$ 200,000,000
Temporary Equity, Liquidation Preference Per Share (in dollars per share) | $ / shares					$ 100
Convertible Preferred Stock, Shares Issued upon Conversion (in shares) | shares					5.7471
Preferred Stock Initial Conversion Price Per Share Of Common Stock (in dollars per share) | $ / shares					$ 17.40
Series A Preferred Stock [Member] | Repurchase And Exchange Agreement [Member]
Stock Repurchased During Period, Shares (in shares) | shares				1,000,000,000,000
Payments for Repurchase of Preferred Stock and Preference Stock				$ 100,641,667
Series B Preferred Stock [Member]
Preferred Stock, Dividend Rate, Percentage				4.00%
Temporary Equity, Liquidation Preference Per Share (in dollars per share) | $ / shares											$ 100
Preferred Stock, Redemption Price Per Share (in dollars per share) | $ / shares									$ 100
Preferred Stock, No Par Value (in dollars per share) | $ / shares				$ 0
Convertible Preferred Stock, Shares Issued upon Conversion (in shares) | shares					1,000,000
Temporary Equity Issuance Of Redeemable Convertible Preferred Stock Net Of Offering Costs And Derivative Liability				$ 93,000,000
Derivative Liability, Subject to Master Netting Arrangement, before Offset				1,000,000
Temporary Equity, Fair Value of Preferred Stock at Issuance				95,000,000
Debt Instrument, Convertible, Stock Price Trigger (in dollars per share) | $ / shares							$ 14.50
Debt Instrument, Convertible, Threshold Trading Days							45
Debt Instrument, Convertible, Threshold Consecutive Trading Days							60
Embedded Derivative, Fair Value of Embedded Derivative Liability				$ 1,000,000
Series B Preferred Stock [Member] | Other Noncurrent Liabilities [Member]
Embedded Derivative, Fair Value of Embedded Derivative Liability							$ 1,000,000		$ 1,000,000
Series B Preferred Stock [Member] | Purchase Agreement [Member]
Convertible Preferred Stock, Shares Issued upon Conversion (in shares) | shares				9.5238
Temporary Equity, Fair Value of Preferred Stock at Issuance				$ 95,000,000
Preferred Stock, Convertible, Conversion Price (in dollars per share) | $ / shares				$ 10.50
Series B Preferred Stock [Member] | Repurchase And Exchange Agreement [Member]
Preferred Stock, Dividend Rate, Percentage				4.00%
Stock Issued During Period, Shares, New Issues (in shares) | shares				1,000,000,000,000
Dividends and Interest Paid				$ 641,667
Series C Preferred Stock [Member]
Proceeds from Issuance of Preferred Stock and Preference Stock								0	99,000,000	$ 0
Preferred Stock, Redemption Price Per Share (in dollars per share) | $ / shares											$ 100
Temporary Equity Issuance Of Redeemable Convertible Preferred Stock Net Of Offering Costs And Derivative Liability								97,000,000
Derivative Liability, Subject to Master Netting Arrangement, before Offset				2,000,000
Transaction Costs				1,000,000
Debt Instrument, Convertible, Threshold Trading Days							45
Debt Instrument, Convertible, Threshold Consecutive Trading Days							60
Embedded Derivative, Fair Value of Embedded Derivative Liability				$ 2,000,000
Series C Preferred Stock [Member] | After February Twenty Six Two Thousand Twenty Three [Member] | Forecast [Member]
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger		200.00%
Series C Preferred Stock [Member] | After February Twenty Six Two Thousand Twenty Four [Member] | Forecast [Member]
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger	150.00%
Series C Preferred Stock [Member] | Other Noncurrent Liabilities [Member]
Embedded Derivative, Fair Value of Embedded Derivative Liability								$ 1,000,000	$ 2,000,000
Series C Preferred Stock [Member] | Purchase Agreement [Member]
Temporary Equity, Shares Issued (in shares) | shares			250,000	750,000				100,000,000
Preferred Stock, Dividend Rate, Percentage				5.00%
Temporary Equity, Liquidation Preference Per Share (in dollars per share) | $ / shares				$ 100
Preferred Stock, No Par Value (in dollars per share) | $ / shares				$ 0
Gross Proceeds From Issuance Of Preferred Stock And Preference Stock			$ 25,000,000	$ 75,000,000
Preferred Stock, Convertible, Conversion Price (in dollars per share) | $ / shares				$ 10
Convertible Preferred Stock, Shares Reserved for Future Issuance (in shares) | shares				1,000,000
Gross Proceeds Owed on Issuance of PreferredStock				$ 100,000,000
Series C Preferred Stock [Member] | Dividend And Other Rights [Member]
Preferred Stock, Dividend Rate, Percentage				5.00%