Financing Receivables - Analysis of Age of Financing Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Receivables [Abstract]
1 to 90 Days Past Due	$ 980	$ 228
91 to 180 Days Past Due	171	31
181 Days Past Due	0	34
Total Past Due	$ 1,151	$ 293