Note 2 - Summary of Significant Accounting Policies - Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Total restricted cash	$ 1,287	$ 61,881
Principal and Interest Payments Held as Collateral For Asset-Backed Securities Issued [Member]
Cash collateral for borrowed securities		50,455
Principal and Interest Payments Held to Secure Borrowings Under Credit Facilities [Member]
Cash collateral for borrowed securities		7,903
Cash Collateral Supporting Standby Letters of Credit [Member]
Cash collateral for borrowed securities		2,302
Deposits for Operating Leases [Member]
Deposits for operating leases	$ 1,287	$ 1,221

Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

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