Note 9 - Notes Payable (Details Textual) - USD ($) $ in Thousands	1 Months Ended							3 Months Ended		6 Months Ended
	May 31, 2022	Nov. 30, 2021	Sep. 30, 2021	Jun. 30, 2021	Oct. 31, 2020	Jul. 31, 2020	Nov. 30, 2019	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2022	Dec. 31, 2021	Jan. 31, 2021	Aug. 31, 2019	Jun. 30, 2019	Dec. 31, 2018	Dec. 31, 2017	Oct. 31, 2015
Long-Term Line of Credit, Total								$ 1,406,070		$ 1,406,070	$ 1,255,518
Proceeds from Issuance of Long-term Debt, Total		$ 300,000		$ 300,000	$ 250,000	$ 100,000	$ 200,000
Asset Backed Securities, Term of Revolving Structure (Year)		3 years	24 months	4 years	41 months	3 years	3 years
Asset Backed Securities, Term of Revolving Structure, Subsequent Amortization Period (Month)		18 months			18 months	18 months
Asset Backed Securities, Weighted Average Interest Rate		3.53%		4.24%	4.10%	5.47%	4.91%
Term Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity												$ 25,000
Long-Term Line of Credit, Total												$ 25,000
Second Term Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity			$ 75,000
Long-Term Line of Credit, Total								0		0
Debt Instrument, Interest Rate, Stated Percentage			2.75%
Term Note [Member]
Long-term Debt, Total													$ 17,400
Debt Instrument, Interest Rate, Stated Percentage													8.00%
Senior Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage		6.125%
Debt Instrument, Face Amount		$ 150,000
Amortization of Debt Issuance Costs								$ 400		$ 700
Minimum [Member]
Asset Backed Securities, Term of Revolving Structure, Subsequent Amortization Period (Month)				11 months			12 months
Minimum [Member] | Term Facility [Member]
Debt Instrument, Interest Rate, Stated Percentage								4.00%		4.00%
Maximum [Member]
Asset Backed Securities, Term of Revolving Structure, Subsequent Amortization Period (Month)				18 months			18 months
Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity																	$ 50,000
Long-Term Line of Credit, Total								$ 28,100		$ 28,100
Secured by the Financial and Operating Assets of CAR [Member]
Line of Credit Facility, Maximum Borrowing Capacity								55,000		55,000
Long-Term Line of Credit, Total								46,400		46,400
Additional Trust Funding Notes Facilities [Member]
Line of Credit Facility, Maximum Borrowing Capacity								110,000		110,000					$ 200,000
Long-Term Line of Credit, Total								0		0
December 2017 Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity																$ 25,000
Long-Term Line of Credit, Total								11,000		11,000
June 2019 Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity														$ 15,000
Long-Term Line of Credit, Total								$ 5,500		$ 5,500
May 2022 Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 250,000
Long-Term Line of Credit, Total	$ 150,000
Asset Backed Securities, Term of Revolving Structure (Year)	5 years
Asset Backed Securities, Term of Revolving Structure, Subsequent Amortization Period (Month)	18 months
Asset Backed Securities, Weighted Average Interest Rate	6.33%
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Variable Rate								1.79%		1.79%
London Interbank Offered Rate (LIBOR) [Member] | Revolving Credit Facility [Member]
Debt Instrument, Basis Spread on Variable Rate									3.00%
London Interbank Offered Rate (LIBOR) [Member] | Secured by the Financial and Operating Assets of CAR [Member] | Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate										2.40%
London Interbank Offered Rate (LIBOR) [Member] | Secured by the Financial and Operating Assets of CAR [Member] | Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate										3.00%
London Interbank Offered Rate (LIBOR) [Member] | Additional Trust Funding Notes Facilities [Member] | Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate										4.50%
London Interbank Offered Rate (LIBOR) [Member] | Additional Trust Funding Notes Facilities [Member] | Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate										6.50%
London Interbank Offered Rate (LIBOR) [Member] | December 2017 Revolving Credit Facility [Member]
Debt Instrument, Basis Spread on Variable Rate										3.50%
Prime Rate [Member]
Debt Instrument, Variable Rate								4.75%		4.75%
Commercial Paper Rates [Member] | Additional Trust Funding Notes Facilities [Member]
Debt Instrument, Basis Spread on Variable Rate										3.15%