5. Interest Income and Interest Expense (Details 1) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Total interest expense	$ 24,062	$ 22,088
Securitization Trust Debt [Member]
Total interest expense	21,829	20,080
Warehouse Lines of Credit [Member]
Total interest expense	1,887	1,708
Subordinated renewable notes [Member]
Total interest expense	$ 346	$ 300

Amount of the cost of borrowed funds accounted for as interest expense.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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