Note 9 - Fair Value Measurement (Details Textual)	Sep. 30, 2023 USD ($)
IQ Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes Payable, Total	$ 36,000,000
Fair Value, Inputs, Level 1 [Member] | IQ Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes Payable, Fair Value Disclosure	$ 34,200,000
Fair Value, Inputs, Level 3 [Member] | IQ Notes [Member] | Measurement Input, Annual Yield [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Instrument, Measurement Input	0.0806
Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes Payable, Total	$ 471,000,000
Senior Notes [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes Payable, Fair Value Disclosure	$ 460,200,000