5. Interest Income and Interest Expense (Details - Interest expense) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Total interest expense	$ 25,187	$ 23,236	$ 49,249	$ 45,324
Securitization Trust Debt [Member]
Total interest expense	22,255	20,537	44,084	40,617
Warehouse Lines of Credit [Member]
Total interest expense	2,135	2,379	4,023	4,087
Residual interest financing [Member]
Total interest expense	452	0	452	0
Subordinated renewable notes [Member]
Total interest expense	$ 345	$ 320	$ 690	$ 620