Collateralized Receivables and Transfers of Financial Assets Collateralized Receivables and Transfers of Financial Assets, Allowance for Collateralized Receivables (Details) - Collateralized Receivables [Member] $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($)
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ (607)
Lower of cost or market write-downs	699
Increase to reserve balance	(961)
Total activity	(262)
Ending balance	$ (869)